Substrate treating apparatus

BACKGROUND OF THE INVENTION

(1) Field of the Invention

This invention relates to a substrate treating apparatus for performing a series of treatments of substrates such as semiconductor wafers, glass substrates for liquid crystal displays, glass substrates for photomasks, and substrates for optical disks (hereinafter called simply substrates).

(2) Description of the Related Art

Conventionally, such a substrate treating apparatus is used, for example, in a photolithographic process for forming photoresist film on substrates, exposing the substrates having the photoresist film formed thereon, and developing the exposed substrates.

This apparatus will be described with reference to a plan view shown in FIG.

1

. This substrate treating apparatus includes an indexer

103

having a cassette table

101

for receiving a plurality of cassettes C each containing a plurality of (e.g. 25) wafers W to be treated, or wafers W having been treated in treating units

104

described hereinafter, and a transport mechanism

108

a

movable horizontally along the cassettes C for transporting the wafers W between the cassettes C and treating units

104

. The apparatus further includes, besides the treating units

104

, a main substrate transport path

105

along which the wafers W are transported from one treating unit

104

to another, and an interface

106

for transferring the wafers W between the treating units

104

and an external treating apparatus

107

.

The external treating apparatus

107

is an apparatus separate from the substrate treating apparatus, and is detachably attached to the interface

106

of the substrate treating apparatus. Where the substrate treating apparatus is designed for resist application and development as noted above, the external treating apparatus

107

is an exposing apparatus for exposing the wafers W.

The substrate treating apparatus further includes a main transport mechanism

108

b

movable along the main substrate transport path

105

, and a transport mechanism

108

c

movable along a transport path of the interface

106

. In addition, a table

109

a

is disposed at a connection between the indexer

103

and main substrate transport path

105

, and a table

109

b

at a connection between the main substrate transport path

105

and interface

106

.

The above substrate treating apparatus performs substrate treatment through the following procedure. The transport mechanism

108

a

takes one wafer W out of a cassette C containing wafers W to be treated, and transports this wafer W to the table

109

a

to pass the wafer W to the main transport mechanism

108

b.

The main transport mechanism

108

b,

after receiving the wafer W placed on the table

109

a,

transports the wafer W into each treating unit

104

for a predetermined treatment (e.g. resist application) in the treating unit

104

. Upon completion of each predetermined treatment, the main transport mechanism

108

b

takes the wafer W out of the treating unit

104

, and transports the wafer W into another treating unit

104

for a next treatment (e.g. heat treatment).

The plurality of treating units

104

include those for performing heat treatment (hereinafter called “heat-treating units” as appropriate). Some heat-treating units

104

perform, for example, heat treatment after resist application for heat-treating the wafers with photoresist film formed thereon, and other heat-treating units

104

perform heat treatment after exposure for heat-treating the wafers having undergone an exposing process to be described hereinafter. Each heat-treating unit

104

has a hot plate for heating wafers W and a cool plate for cooling the wafers W having been heated, the two plates being arranged one above the other, and a local transport mechanism separate from and independent of the main transport mechanism

108

b

for transporting the wafers W between the hot plate and cool plate.

The local transport mechanism is provided for each heat-treating unit separately from the main transport mechanism

108

b

for the following reasons. For the two types of heat treatment after resist application and after exposure noted above, the time taken after a fixed time of heating by the hot plate until the cooling treatment by the cool plate is extremely important from the processing point of view. Variations in that time (i.e. cooling starting time after the heating treatment) would cause variations in film thickness after the resist application or variations in line-width uniformity after the development. If, for example, the main transport mechanism

108

b

transported the wafer W also between the hot plate and cool plate in each heat-treating unit, it would be difficult to cool, immediately after heating, all of the wafers successively loaded for treatment, because of the time taken in transport to other treating units

104

and the time taken in treatment in other treating units

104

. This would result in a so-called overbaking or variations in the cooling starting time after the heating treatment. Thus, the independent local transport mechanism is provided separately from the main transport mechanism

108

b

to ensure a fixed cooling starting time after the heating treatment.

Further, if the same main transport mechanism were used to transfer wafers to and from the hot plate, the main transport mechanism would become heated and inadvertently apply heat to the wafers. This would affect treatment in other treating units

104

such as resist application and development. The independent local transport mechanism is provided to avoid such an inconvenience also.

After the series of pre-exposure treatment is completed, the main transport mechanism

108

b

transports the wafer W treated in the treating units

104

to the table

109

b,

and deposits the wafer on the table

109

b

to pass the wafer W to the transport mechanism

108

c.

The transport mechanism

108

c

receives the wafer W placed on the table

109

b

and transports the wafer W to the external treating apparatus

107

. The transport mechanism

108

c

loads the wafer W into the external treating apparatus

107

and, after a predetermined treatment (e.g. exposure), takes the wafer W out of the external treating apparatus

107

to transport it to the table

109

b.

Subsequently, the main transport mechanism

108

b

transports the wafer W to the treating units

104

where a series of post-exposure heating and cooling treatment and development is performed. The wafer W having gone through all the treatment is loaded by the transport mechanism

108

a

into a predetermined cassette C. The cassette C is transported away from the cassette table

101

to complete a series of substrate treatment.

The conventional apparatus having such a construction has the following drawback.

The conventional substrate treating apparatus has the local transport mechanism in each heat-treating unit for transporting the wafer W between the hot plate and cool plate to secure a fixed cooling starting time after heating treatment as noted above. In this way, an effort is made for improvement in substrate treating precision. However, variations still occur in substrate treating precision; substrates cannot be treated with high precision.

SUMMARY OF THE INVENTION

This invention has been having regard to the state of the art noted above, and its object is to provide a substrate treating apparatus for treating substrates with high precision.

To solve the problem noted above, Inventor has made intensive research and attained the following findings. In the conventional substrate treating apparatus, the local transport mechanism of the heat-treating unit is provided for transporting wafers W between the hot plate and cool plate. The local transport mechanism accesses the hot plate or cool plate in time of wafer transport, and stands by outside the hot plate and cool plate at other times. That is, the local transport mechanism of the heat-treating unit has a standby position set outside the hot plate and cool plate, and stands by in the environment outside the heat-treating unit after transporting a wafer to the hot plate or cool plate. Thus, not only is the local transport mechanism easily affected by the influence (e.g. thermal influence) of the environment outside the heat-treating unit, but, conversely, the local transport mechanism exerts an influence (e.g. thermal influence) on the environment outside the heat-treating unit. It has been found that the influence on the local transport mechanism of the environment outside the heat-treating unit and vice versa are in a causal relationship with variations in substrate treating precision and a lowering of treating precision of the substrate treating apparatus.

Based on the above findings, this invention provides a substrate treating apparatus for performing a series of treatments on a substrate, comprising a heat-treating unit for heat-treating the substrate, and a main transport device for transferring the substrate between the heat-treating unit and a different unit, the heat-treating unit including a plurality of substrate treating sections arranged vertically, and a local transport device provided separately from the main transport device for transferring the substrate between the substrate treating sections, one of the substrate treating sections providing a standby position for the local transport device.

According to the above apparatus, the local transport device, when on standby, is placed in the standby position inside one of the substrate treating sections of the heat-treating unit. Consequently, the local transport device is less influenced by the environment outside the heat-treating unit than where the local transport device is kept on standby outside the heat-treating unit. The local transport device on standby influences the environment outside the heat-treating unit to a reduced degree. Variations in substrate treating precision due to such adverse influences may be reduced to perform substrate treatment with high precision. Further, temperature control of the local transport device may be effected easily. The local transport device capable of transferring the substrate between the plurality of substrate treating sections in the heat-treating unit lightens the burden on the main transport device.

Preferably, the substrate treating sections include a substrate heating section for heating the substrate, and one of a substrate cooling section for cooling the substrate and a substrate standby section for keeping the substrate on standby, the standby position being set inside one of the substrate cooling section and the substrate standby section. Thus, the local transport device, when on standby, is placed in the standby position inside the substrate cooling section or substrate standby section. The local transport device on standby is less influenced by the environment outside the heat-treating unit, and influences the environment outside the heat-treating unit to a reduced degree. Variations in substrate treating precision due to such adverse influences may be reduced to perform substrate treatment with high precision. Where the standby position is set inside the substrate cooling section, the local transport device on standby may be cooled.

Preferably, the local transport device includes a substrate cooling device for cooling the substrate held by the local transport device. This local transport device not only transports the substrate, but can start cooling the substrate the moment it holds the substrate.

Preferably, at least one of the substrate treating sections has, formed separately from each other, a local transport opening for access by the local transport device, and a main transport opening for access by the main transport device. This construction reduces the chance of interference between the local transport device and main transport device.

Preferably, one of the substrate cooling section and the substrate standby section includes a cooling device for cooling the local transport device on standby. The cooling device may cool the local transport device on standby inside the substrate cooling section or substrate standby section.

Preferably, the substrate treating sections include at least two substrate heating sections for heating the substrate, one of the substrate heating sections providing the standby position for the local transport device. With this construction, the local transport device on standby is placed in the standby position inside one of the substrate heating sections. Thus, the local transport device on standby is less influenced by the environment outside the heat-treating unit, and influences the environment outside the heat-treating unit to a reduced degree. Further, the local transport device on standby may be heated.

Alternatively, the substrate treating sections may include at least two substrate cooling sections for cooling the substrate, one of the substrate cooling sections providing the standby position for the local transport device. With this construction, the local transport device on standby is placed in the standby position inside one of the substrate cooling sections. Thus, the local transport device on standby is less influenced by the environment outside the heat-treating unit, and influences the environment outside the heat-treating unit to a reduced degree. Further, the local transport device on standby may be cooled.

This specification discloses also the following substrate treating method, substrate heat-treating apparatus and substrate transporting methods for a substrate treating apparatus:

(1) A substrate treating method for performing a series of treatments on a substrate, comprising:

a main transport step for transporting the substrate with a main transport device between a heat-treating unit for heat-treating the substrate and a different unit;

a local transport step for transporting the substrate with a local transport device between a plurality of substrate treating sections arranged vertically in the heat-treating unit; and

a standby step for placing the local transport device having transported the substrate to a predetermined one of the substrate treating sections in the heat-treating unit, in a standby position set inside a different one of the substrate treating sections.

According to the substrate treating method (1) above, the standby step is executed to place the local transport device having transported the substrate to a substrate treating section, in a standby position set inside a different substrate treating section. Consequently, the local transport device is less influenced by the environment outside the heat-treating unit than where the local transport device is kept on standby outside the heat-treating unit. The local transport device on standby influences the environment outside the heat-treating unit to a reduced degree. Variations in substrate treating precision due to such adverse influences may be reduced to perform substrate treatment with high precision. Further, temperature control of the local transport device may be effected easily. The local transport device capable of transferring the substrate between the plurality of substrate treating sections in the heat-treating unit lightens the burden on the main transport device.

(2) A substrate treating apparatus for performing a series of treatments on a substrate, comprising:

a plurality of substrate treating sections arranged vertically for performing predetermined treatments on the substrate; and

a local transport device provided separately from a main transport device that transfers the substrate between the substrate treating apparatus and a different apparatus, the local transport device transferring the substrate between the substrate treating sections;

one of the substrate treating sections providing a standby position for the local transport device.

According to the substrate treating apparatus (2) above, the local transport device, when on standby, is placed in the standby position inside one of the substrate treating sections of the heat-treating unit. Consequently, the local transport device is less influenced by the environment outside the heat-treating unit than where the local transport device is kept on standby outside the heat-treating unit. The local transport device on standby influences the environment outside the heat-treating unit to a reduced degree. Variations in substrate treating precision due to such adverse influences may be reduced to perform substrate treatment with high precision. Further, temperature control of the local transport device may be effected easily. The local transport device capable of transferring the substrate between the plurality of substrate treating sections in the heat-treating unit lightens the burden on the main transport device.

(3) A substrate transport method for a substrate treating apparatus for performing a series of treatments on a substrate, comprising:

a first main transport step for transporting the substrate with a first main transport device between a substrate treating section for cooling or standby in a heat-treating unit for heat-treating the substrate, and a different unit;

a second main transport step for transporting the substrate with a second main transport device between a substrate heat-treating section different from the substrate treating section for cooling or standby in the heat-treating unit, and another different unit;

a local transport step for transporting the substrate with a single local transport device separate from the first and second main transport devices, between the substrate treating section for cooling or standby and the substrate heat-treating section arranged vertically in the heat-treating unit; and

a standby step for placing the local transport device having transported the substrate to one of the substrate treating section for cooling or standby and the substrate heat-treating section in the heat-treating unit, in a standby position set inside the other of the substrate treating section for cooling or standby and the substrate heat-treating section.

According to the substrate transport method (3) above, the standby step is executed to place the local transport device having transported the substrate to one substrate treating section, in a standby position set inside a different substrate treating section. Consequently, the local transport device is less influenced by the environment outside the heat-treating unit than where the local transport device is kept on standby outside the heat-treating unit. The local transport device on standby influences the environment outside the heat-treating unit to a reduced degree. Variations in substrate treating precision due to such adverse influences may be reduced to perform substrate treatment with high precision. Further, temperature control of the local transport device may be effected easily. The first main transport device accesses only the substrate treating section for cooling or standby, while the second main transport device accesses only the substrate heat-treating section. Thus, a thermal separation is provided between the first main transport device and second main transport device.

(4) A substrate transport method in a substrate treating apparatus for performing a series of treatments on a substrate, comprising:

a main transport step for transporting the substrate with a single main transport device between a particular one of a plurality of substrate treating sections arranged vertically in a heat-treating unit for heat-treating the substrate, and a different unit;

a local transport step for transporting the substrate with a single local transport device separate from the main transport device, between the substrate treating sections in the heat-treating unit; and

a standby step for placing the local transport device having transported the substrate from the particular one of the substrate treating sections to a different one of the substrate treating sections, in a standby position set inside the particular one of the substrate treating sections.

According to the substrate transport method (4) above, the standby step is executed to place the local transport device having transported the substrate to a substrate treating section other than a particular substrate treating section, in a standby position set inside the particular substrate treating section. Consequently, the local transport device is less influenced by the environment outside the heat-treating unit than where the local transport device is kept on standby outside the heat-treating unit. The local transport device on standby influences the environment outside the heat-treating unit to a reduced degree. Variations in substrate treating precision due to such adverse influences may be reduced to perform substrate treatment with high precision. Further, temperature control of the local transport device may be effected easily.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, there are shown in the drawings several forms which are presently preferred, it being understood, however, that the invention is not limited to the precise arrangement and instrumentalities shown.

FIG. 1

is a block diagram showing the construction of a conventional substrate treating apparatus;

FIG. 2

is a plan view showing an outline of a substrate treating apparatus in a first embodiment of this invention;

FIG. 3A

is a schematic perspective view showing an outward appearance of a heat-treating unit;

FIG. 3B

is an explanatory view showing a substrate transport path in the heat-treating unit;

FIG. 4

is a schematic perspective view showing an outward appearance of a local transport mechanism;

FIG. 5

is a sectional view of the heat-treating unit taken on line

201

—

201

of

FIG. 3A

;

FIG. 6

is a sectional view of the heat-treating unit taken on line

202

—

202

of

FIG. 3A

;

FIGS. 7A through 7C

are views illustrating operation of the local transport mechanism in the heat-treating unit;

FIGS. 8A through 8C

are views illustrating operation of the local transport mechanism in the heat-treating unit;

FIGS. 9A and 9B

are views illustrating operation of the local transport mechanism in the heat-treating unit;

FIG. 10

is a plan view showing an outline of a substrate treating apparatus in a second embodiment of this invention;

FIG. 11A

is a schematic perspective view showing an outward appearance of a heat-treating unit;

FIG. 11B

is an explanatory view showing a substrate transport path in the heat-treating unit;

FIGS. 12A through 12C

are views illustrating operation of a local transport mechanism in the heat-treating unit;

FIGS. 13A through 13C

are views illustrating operation of the local transport mechanism in the heat-treating unit;

FIGS. 14A and 14B

are views illustrating operation of the local transport mechanism in the heat-treating unit;

FIG. 15

is a schematic plan view of a modified local transport mechanism; and

FIG. 16

is a schematic plan view of another modified local transport mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of this invention will be described in detail hereinafter with reference to the drawings.

<First Embodiment>

A substrate treating apparatus in a first embodiment of this invention will be described.

FIG. 2

is a plan view showing an outline of the substrate treating apparatus in the first embodiment.

The substrate treating apparatus in the first embodiment, as described hereinafter, performs a series of substrate treatments, and has, for example, a spin coater for performing resist application while spinning substrates in a photolithographic process, and a spin developer for performing development while spinning the substrates having undergone the resist application and an exposing process.

As shown in

FIG. 2

, the substrate treating apparatus in the first embodiment includes an indexer

1

, a treating block

3

and an interface

4

. The interface

4

is arranged to connect the substrate treating apparatus in the first embodiment and a different apparatus. In the first embodiment, the interface

4

connects the substrate treating apparatus for performing the resist application and development, and an exposing apparatus (e.g. a stepper for performing step-and-repeat exposure) STP, shown in a two-dot chain line in

FIG. 2

, for exposing the substrates.

As shown in

FIG. 2

, the indexer

1

includes a cassette table

2

, a transport path

7

and a transport mechanism

8

. The cassette table

2

is constructed for receiving thereon a plurality of (four in

FIG. 2

) cassettes C each containing a plurality of (e.g. 25) wafers W to be treated or wafers W already treated. The transport path

7

extends horizontally along the cassette table

2

having the plurality of cassettes C placed thereon. The transport mechanism

8

has a horizontal moving mechanism, a vertical moving mechanism and a rotating mechanism not shown. In the transport path

7

, the transport mechanism

8

is movable horizontally and vertically for transferring the wafers W between the cassettes C on the cassette table

2

and the treating block

3

.

A specific construction of the treating block

3

will be described next. The treating block

3

includes a plurality of treating units, and a main transport mechanism for transporting wafers W between these treating units.

The above treating units, as described hereinafter, include a BARC unit, a post-BARC heat-treating unit, an SC unit, a post-SC heat-treating unit, and an EE unit, which perform treatment before the transfer to the exposing apparatus STP, and a PEB unit which is a post-EE heat-treating unit, an SD unit, and a post-EE heat-treating unit, for performing post-exposure treatment of the wafers received from the exposing apparatus STP.

For example, the BARC unit is operable to form a bottom anti-reflection coating (hereinafter referred to as “BARC”) on the wafer W for preventing reflection of light from photoresist film formed on the wafer W. Before the BARC treatment in the BARC unit, an adhesion treatment (hereinafter referred to as “AHL”) is carried out for improving cohesion between the wafer W and photoresist film.

The post-BARC heat-treating unit is operable to heat and bake the wafer W after the BARC treatment in the BARC unit. The SC unit has a spin coater (hereinafter referred to as “SC”) for forming photoresist film on the wafer W while spinning the wafer W. The post-SC heat-treating unit is operable to heat and bake the wafer W after the photoresist film is formed thereon in the SC unit. The EE unit is operable to expose edges of the wafer W, i.e. edge exposure (hereinafter referred to as “EE”).

The PEB unit is for heating the wafer W after exposure, i.e. post-exposure bake (hereinafter referred to as “PEB”). The SD unit has a spin developer (hereinafter referred to as “SD”) for developing the exposed wafer W while spinning the wafer W. The post-SD heat-treating unit is operable to heat and bake the wafer W after the development in the SD unit.

In the first embodiment, as shown in

FIG. 2

, the main transport mechanism is a dual mechanism including a first main transport mechanism TR

1

and a second main transport mechanism TR

2

.

FIG. 2

illustrates, in a portion of treating block

3

, how the first main transport mechanism TR

1

transports a wafer W from one different unit to a certain heat-treating unit

20

among the heat-treating units noted above, and the second main transport mechanism TR

2

transports the wafer W heat-treated in this heat-treating unit

20

to another unit. The first and second main transport mechanisms TR

1

and TR

2

correspond to the main transport device of this invention.

The construction of the heat-treating unit

20

will be described with reference to

FIGS. 3 through 6

.

FIG. 3A

is a schematic perspective view showing an outward appearance of the heat-treating unit

20

.

FIG. 3B

is an explanatory view showing a transport path of wafer W in the heat-treating unit

20

.

FIG. 4

is a schematic perspective view showing an outward appearance of a local transport mechanism

50

.

FIG. 5

is a sectional view of the heat-treating unit

20

taken on line

201

—

201

of FIG.

3

A.

FIG. 6

is a sectional view of the heat-treating unit

20

taken on line

202

—

202

of FIG.

3

A.

As shown in

FIGS. 3A and 3B

, the heat-treating unit

20

includes a cooling unit

30

for cooling the wafer W, a heating unit

40

disposed under the cooling unit

30

for heating the wafer W, and a local transport mechanism

50

provided separately from the first and second main transport mechanisms TR

1

and TR

2

for transferring the wafer W between the cooling unit

30

and heating unit

40

. The cooling unit

30

, heating unit

40

and local transport mechanism

50

will be described hereinafter in the state order.

As shown in

FIG. 3B

, the cooling unit

30

includes a cooler

31

for forcibly cooling its interior space for accommodating the wafer W. The cooler

31

may effect the forcible cooling by using, for example, a cooling gas, cooling water or thermo-electric cooling elements (e.g. Peltier elements). As shown in

FIGS. 5 and 6

, the cooling unit

30

has a plurality of (e.g. three) support pins

32

arranged in predetermined positions spaced from one another therein. The wafer W has an undersurface thereof contacting upper ends of the three support pins

32

to be held in horizontal posture for cooling treatment. The cooling unit

30

has a housing

33

with an access opening

34

formed in a front wall

33

a

thereof for the first main transport mechanism TR

1

to load the wafer W transported from a different treating unit into the cooling unit

30

. The housing

33

of the cooling unit

30

has an access opening

35

formed in a rear wall

33

b

thereof for the local transport mechanism

50

to unload the wafer W from the cooling unit

30

. The main transport mechanism access opening

34

and local transport mechanism access opening

35

have shutter mechanisms (not shown), for example. Each shutter mechanism opens the access opening

34

or

35

in time of access by the first main transport mechanism TR

1

or local transport mechanism

50

, and keeps the access opening

34

or

35

closed at other times.

The above access opening

34

corresponds to the main transport mechanism access opening of this invention. The access opening

35

corresponds to the local transport mechanism access opening of this invention.

The heating unit

40

will be described next. As shown in

FIG. 6

, the heating unit

40

includes a heating furnace (chamber)

41

for heating the wafer W. The heating furnace

41

has a container body

41

a

for receiving the wafer W, an openable top cover

41

b

for closing an opening of the container body

41

a,

and a hot plate

41

c

for heating the wafer W placed on an upper surface thereof. The heating furnace

41

has a plurality of (e.g. three) support pins

42

arranged in predetermined positions spaced from one another therein. The wafer W has the undersurface thereof contacting upper ends of the three support pins

42

to be held in horizontal posture. A lift mechanism not shown is operable to lower the support pins

42

, whereby the wafer W is laid on the upper surface of hot plate

41

c

for heating treatment. The heating unit

40

has a housing

43

with an access opening

45

formed in a rear wall

43

b

thereof for the local transport mechanism

50

to load the wafer W transported from the cooling unit

30

into the heating unit

40

. The housing

43

of the heating unit

40

has an access opening

44

formed in a front wall

43

a

thereof for the second main transport mechanism TR

2

to unload the wafer W from the heating unit

40

. The main transport mechanism access opening

44

and local transport mechanism access opening

45

have shutter mechanisms (not shown), for example. Each shutter mechanism opens the access opening

44

or

45

in time of access by the second main transport mechanism TR

2

or local transport mechanism

50

, and keeps the access opening

44

or

45

closed at other times.

The above access opening

44

corresponds to the main transport mechanism access opening of this invention. The access opening

45

corresponds to the local transport mechanism access opening of this invention.

The construction of the local transport mechanism

50

will be described hereinafter. As shown in

FIGS. 4 through 6

, the local transport mechanism

50

includes a plate

51

for holding the wafer W in horizontal posture, a vertical moving mechanism

60

for vertically moving the plate

51

, and a horizontal moving mechanism

70

for horizontally moving the plate

51

.

As shown in

FIGS. 4 and 5

, the plate

51

has a substrate holding portion

52

adjacent a forward end thereof for holding the wafer W in horizontal posture. The substrate holding portion

52

has a plurality of small projections (e.g. hemispherical projections)

52

a

slightly projecting in z-direction from an upper surface thereof for holding the wafer W. Thus, only the small projections

52

a

contact the undersurface of wafer W to support the wafer W through point contact, leaving a slight gap between the undersurface of wafer W and the upper surface of plate

51

. The substrate holding portion

52

has a plurality of (e.g. three) cutouts

53

formed therein to extend in y-direction. When the substrate holding portion

52

is moved into the cooling unit

30

or heating unit

40

, the cutouts

53

receive the three support pins

32

for supporting the wafer W in the cooling unit

30

or the three support pins

42

for supporting the wafer W in the heating unit

40

, in order that the substrate holding portion

52

does not collide with the support pins

32

or

42

.

As shown in

FIG. 4

, the vertical moving mechanism

60

includes a rotary screw

61

extending vertically (in z-direction) and meshed with a threaded bore

54

formed in a proximal portion of the plate

51

, a lower support plate

63

having a bearing

62

for rotatably supporting the lower end of rotary screw

61

, an upper support plate

65

having a bore

65

a

for receiving the rotary screw

61

in a non-contact manner and a bearing

64

for rotatably supporting the upper end of rotary screw

61

, a guide rail

66

extending vertically (in z-direction) and contacting a guide groove

55

formed in the proximal portion of plate

51

, a motor

67

mounted on the upper support plate

65

to have a rotary shaft

67

a

extending vertically (in z-direction), and a timing belt

69

for connecting a rotary element

67

b

attached to a distal end of the rotary shaft

67

a

of motor

67

to an element

68

fixed to the rotary screw

61

. Thus, when the motor

67

rotates in a predetermined direction (e.g. “forward rotation”), the rotation (forward rotation) of the motor

67

is transmitted to the rotary screw

61

through the timing belt

69

, to rotate the rotary screw

61

forward. Then, the plate

51

is raised along the guide rail

66

. When the motor

67

rotates in a direction reversed from the above (e.g. “backward rotation”), the rotation (backward rotation) of the motor

67

is transmitted to the rotary screw

61

through the timing belt

69

, to rotate the rotary screw

61

backward. Then, the plate

51

is lowered along the guide rail

66

.

As shown in

FIG. 4

, the horizontal moving mechanism

70

includes a bar

71

extending from the upper support plate

65

in a direction (y-direction) for moving the plate

51

back and forth, a motor

72

disposed inside the housing

33

of cooling unit

30

to have a rotary shaft

72

a

thereof extending in x-direction, a rotatable member

73

disposed inside the housing

33

of cooling unit

30

and spaced in y-direction from the motor

72

to have a rotary shaft

73

a

thereof extending in x-direction, a timing belt

75

connecting the rotary shaft

72

a

of motor

72

and the rotatable member

73

and fixed in a predetermined position thereof to a fixed element

74

provided at a distal end of the bar

71

, and a guide rail

77

extending in the direction of movement (y-direction) and contacting a guide groove

76

formed in the distal end of bar

71

. Thus, when the motor

72

rotates in a predetermined direction (e.g. “forward rotation”), the timing belt

75

is driven to move the fixed element

74

away from the motor

72

. Then, the plate

51

and vertical moving mechanism

60

advance along the guide rail

77

(in the direction of +y). When the motor

72

rotates in a direction reversed from the above (e.g. “backward rotation”), the timing belt

75

is driven to move the fixed element

74

toward the motor

72

. Then, the plate

51

and vertical moving mechanism

60

retreat along the guide rail

77

(in the direction of −y).

As shown in

FIG. 6

, the plate

51

of the local transport mechanism

50

, when on standby, is contained in a standby position inside the cooling unit

30

. The plate

51

of the local transport mechanism

50

in the standby position lies adjacent a bottom surface inside the cooling unit

30

. That is, the plate

51

is placed at a predetermined distance below the upper ends of support pins

32

. When the first main transport mechanism TR

1

loads the wafer W on the support pins

32

in the cooling unit

30

, the plate

51

of the local transport mechanism

50

in the standby position remains out of contact or otherwise presents no obstruction.

The construction of the interface

4

will be described next. As shown in

FIG. 2

, the interface

4

includes a transport path

9

, a transport mechanism

10

and a table

11

. The transport path

9

is formed parallel to the transport path

7

of indexer

1

. The transport mechanism

10

has a horizontal moving mechanism, a vertical moving mechanism and a rotating mechanism not shown. Thus, the transport mechanism

10

is horizontally and vertically movable in the transport path

9

to transport wafers W between the tables

11

and the exposing apparatus (stepper) STP shown in two-dot chain lines in FIG.

2

. The exposing apparatus STP is provided separately from and connectable to the apparatus in the first embodiment. Where the wafers W are not transferred between the apparatus in the first embodiment and the exposing apparatus STP, the exposing apparatus STP may be separated from the interface

4

of the apparatus in the first embodiment.

As shown in

FIG. 2

, the table

11

includes, arranged in vertical stages, a Pass

1

for receiving wafers W transferred between the first and second main transport mechanisms TR

1

and TR

2

and the transport mechanism

10

to be delivered to the exposing apparatus STP, a plurality of buffers BF

1

for temporarily storing the wafers W to be delivered to the exposing apparatus STP, a Pass

2

for receiving wafers W from the exposing apparatus STP and transferred between the first and second main transport mechanisms TR

1

and TR

2

and the transport mechanism

10

, and a plurality of buffers BF

2

for temporarily storing the wafers W returned from the exposing apparatus STP.

The local transport mechanism

50

noted above corresponds to the local transport device of this invention. The cooling unit

30

and heating unit

40

constitute the substrate treating sections of this invention. The cooling unit

30

corresponds to the substrate cooling section of this invention. The heating unit

40

corresponds to the substrate heating section of this invention.

Heat treatment in a series of substrate treatments in a photolithographic process by the substrate treating apparatus in the first embodiment, i.e. a heat-treating operation of the heat-treating unit

20

in the treating block

3

, will be described hereinafter with reference to

FIGS. 7 through 9

.

FIGS. 7A through 7C

,

8

A through

8

C, and

9

A and

9

B are views illustrating operation of the local transport mechanism

50

of the heat-treating unit

20

.

(1) Loading of Wafer W into the Cooling Unit

30

by the First Main Transport Mechanism TR

1

:

As shown in

FIG. 7A

, the main transport mechanism access opening

34

of the cooling unit

30

is opened as the first main transport mechanism TR

1

holding a wafer W approaches the access opening

34

. The first main transport mechanism TR

1

holding the wafer W enters the access opening

34

of the cooling unit

30

, and withdraws from the cooling unit

30

after delivering the wafer W, which has been transported from a different treating unit, to a delivery position (e.g. on the three support pins

32

) inside the cooling unit

30

. At this time, the plate

51

of the local transport mechanism

50

is placed in the standby position adjacent the bottom in the cooling unit

30

. When the first main transport mechanism TR

1

loads the wafer W on the support pins

32

in the cooling unit

30

, the first main transport mechanism TR

1

never contacts the plate

51

of the local transport mechanism

50

in the standby position, or the local transport mechanism

50

never obstructs the loading operation. The main transport mechanism access opening

34

of the cooling unit

30

is closed after the first main transport mechanism TR

1

withdraws therefrom. The cooling unit

30

keeps the wafer W on standby. In the cooling unit

30

, the wafer W is cooled, as necessary, during the standby.

(2) Receipt of Wafer W by the Local Transport Mechanism

50

:

Upon completion of the receipt or cooling of the wafer W by the cooling unit

30

, as shown in

FIG. 7B

, the vertical moving mechanism

60

of the local transport mechanism

50

is driven to raise the plate

51

and pick up the wafer W supported on the three support pins

32

. Then, the local transport mechanism access opening

35

of the cooling unit

30

is opened. As shown in

FIG. 7C

, the horizontal moving mechanism

70

of the local transport mechanism

50

is driven to move the plate

51

in y-direction out of the cooling unit

30

. After the plate

51

of the local transport mechanism

50

moves outside, the access opening

35

of the cooling unit

30

is closed.

(3) Loading of Wafer W into the Heating Unit

40

by the Local Transport Mechanism

50

:

As shown in

FIG. 8A

, the vertical moving mechanism

60

of the local transport mechanism

50

is driven to lower the plate

51

to a level for loading the wafer W into the heating unit

40

. Then, the local transport mechanism access opening

45

of the heating unit

40

is opened. As shown in

FIG. 8B

, the horizontal moving mechanism

70

of the local transport mechanism

50

is driven to move the plate

51

in y-direction into the heating unit

40

. As shown in

FIG. 8C

, the vertical moving mechanism

60

is driven to lower the plate

51

to a wafer delivery level to deliver the wafer W to a delivery position (e.g. on the three support pins

42

) inside the heating furnace

41

of the heating unit

40

. Alternatively, the pins

42

of the heating unit

40

are raised to receive the wafer W. Then, the horizontal moving mechanism

70

is driven to withdraw the plate

51

in y-direction out of the heating unit

40

. The plate

51

of the local transport mechanism

50

is further moved in an operation reversed from the foregoing operation. Ultimately, the plate

51

is placed in the standby position adjacent the bottom surface inside the cooling unit

30

as shown in FIG.

7

A. The local transport mechanism access opening of the heating unit

40

is closed after the plate

51

of the local transport mechanism

50

leaves the heating unit

40

.

(4) Heating of Wafer W by the Heating Unit

40

:

As shown in

FIG. 9A

, the heating furnace

41

lowers the top cover

41

b

to close the opening of the container body

41

a,

and lowers the support pins

42

to place the wafer W on the upper surface of hot plate

41

c.

In this state, the wafer W receives a predetermined heating treatment in the heating furnace

41

. After the heating treatment, the heating furnace

41

raises the top cover

41

b

to open the opening of the container body

41

a,

and raises the support pins

42

to support the wafer W in a position away from the upper surface of hot plate

41

c.

As noted hereinbefore, the heating treatment may be performed to bake the wafer W after a bottom coating is formed thereon in the BARC unit, to bake the wafer W after a photoresist film is formed thereon in the SC unit, to bake the wafer W after exposure, i.e. PEB treatment, or to bake the wafer W after development.

(5) Unloading of Wafer W from the Heating Unit

40

by the Second Main Transport Mechanism TR

2

:

The main transport mechanism access opening

44

of the heating unit

40

is opened as the second main transport mechanism TR

2

approaches the access opening

44

. As shown in

FIG. 9B

, the second main transport mechanism TR

2

enters the access opening

44

of the heating unit

40

. The second main transport mechanism TR

2

picks up and holds the wafer W supported by the three support pins

42

raised after the heating treatment in the heating furnace

41

, then withdraws from the heating unit

40

, and transports the heated wafer W to a predetermined different treating unit.

The operations of the first and second main transport mechanisms TR

1

and TR

2

for transporting the wafer W described in sections (1) and (5) above correspond to the main transport step. The operation of the local transport mechanism

50

for transporting the wafer W described in sections (2) and (3) above corresponds to the local transport step. The standby of the local transport mechanism

50

in the standby position inside the cooling unit

30

described in sections (1) and (3) above corresponds to the standby step. More particularly, the operation of the first main transport mechanism TR

1

for transporting the wafer W to the cooling unit

30

described in section (1) above corresponds to the first main transport step. The operation of the second main transport mechanism TR

2

for transporting the wafer W from the heating unit

40

described in section (5) above corresponds to the second main transport step. The operation of the local transport mechanism

50

for transporting the wafer W described in sections (2) and (3) above corresponds to the local transport step. The standby of the local transport mechanism

50

in the standby position inside the cooling unit

30

described in sections (1) and (3) above corresponds to the standby step.

According to the substrate treating apparatus in the first embodiment, as described above, the local transport mechanism

50

, when on standby, is placed in the standby position inside the cooling unit

30

of the heat-treating unit

20

. Consequently, the local transport mechanism

50

is less influenced by the environment outside the heat-treating unit

20

than where the local transport mechanism

50

is kept on standby outside the heat-treating unit

20

. The local transport mechanism

50

on standby influences the environment outside the heat-treating unit

20

to a reduced degree. Variations in substrate treating precision due to such adverse influences may be reduced to perform substrate treatment with high precision. Further, temperature control of the local transport mechanism

50

may be effected easily. The local transport mechanism

50

capable of transferring wafers W between the cooling unit

30

and heating unit

40

in the heat-treating unit

20

lightens the burden on the first and second main transport mechanisms TR

1

and TR

2

.

In the conventional substrate treating apparatus, the local transport mechanism of each heat-treating unit (heat-treating unit among the treating units

104

in

FIG. 1

) remains protruding from this heat-treating unit in a normal state, and temporarily enters the heat-treating unit only in time of substrate transport. The conventional substrate treating apparatus has poor maintenability since the local transport mechanism protruding from the heat-treating unit is obstructive to movement of the interface or the like. However, in the substrate treating apparatus in the first embodiment, the local transport mechanism

50

of the heat-treating unit

20

moves out of the heat-treating unit

20

only temporarily, that is only when transporting wafers W. In a normal state other than the time of transporting wafers W, the local transport mechanism

50

does not protrude from the heat-treating unit

20

. Thus, the substrate treating apparatus in the first embodiment has excellent maintenability in that the interface

4

or the like may be moved without obstruction.

The cooling unit

30

and heating unit

40

have the access openings

35

and

45

for the local transport mechanism

50

separately from the access openings

34

and

44

for the first main transport mechanism TR

1

and second main transport mechanism TR

2

. This arrangement reduces the chance of interference between the local transport mechanism

50

and the first and second main transport mechanisms TR

1

and TR

2

.

Further, the first main transport mechanism TR

1

accesses only the cooling unit

30

of the heat-treating unit

20

, while the second main transport mechanism TR

2

accesses only the heating unit

40

of the heat-treating unit

20

. This provides a thermal separation between the first and second main transport mechanisms TR

1

and TR

2

.

<Second Embodiment>

A second embodiment will be described with reference to

FIGS. 10 and 11

.

FIG. 10

is a plan view showing an outline of a substrate treating apparatus in the second embodiment of this invention.

FIG. 11A

is a schematic perspective view showing an outward appearance of a heat-treating unit

20

.

FIG. 11B

is an explanatory view showing a transport path of wafers W in the heat-treating unit

20

.

In the first embodiment described above, as shown in

FIG. 2

, the treating block

3

includes the two main transport mechanisms (first and second main transport mechanisms TR

1

and TR

2

). The first main transport mechanism TR

1

accesses the cooling unit

30

of the heat-treating unit

20

, while the second main transport mechanism TR

2

accesses the heating unit

40

of the heat-treating unit

20

. In the second embodiment, as shown in

FIG. 10

, the treating block

3

includes only one main transport mechanism (first main transport mechanism TR

1

). The first main transport mechanism TR

1

accesses the cooling unit

30

of the heat-treating unit

20

. Like references are used to identify like parts which are the same as in the first embodiment and will not particularly be described again.

As shown in

FIG. 11

, the heating unit

40

of the heat-treating unit

20

in the second embodiment has, eliminated therefrom, the main transport mechanism access opening

44

formed in the front wall of housing

43

and the shutter mechanism (not shown) for opening and closing this access opening

44

which are provided for the heating unit

40

in the first embodiment described hereinbefore.

Heat treatment in a series of substrate treatments in a photolithographic process by the substrate treating apparatus in the second embodiment, i.e. a heat-treating operation of the heat-treating unit

20

in the treating block

3

, will be described hereinafter with reference to

FIGS. 12 through 14

.

FIGS. 12A through 12C

,

13

A through

13

C, and

14

A and

14

B are views illustrating operation of the local transport mechanism

50

of the heat-treating unit

20

.

(11) Loading of Wafer W into the Cooling Unit

30

by the First Main Transport Mechanism TR

1

:

As shown in

FIG. 12A

, the main transport mechanism access opening

34

of the cooling unit

30

is opened as the first main transport mechanism TR

1

holding a wafer W approaches the access opening

34

. The first main transport mechanism TR

1

holding the wafer W enters the access opening

34

of the cooling unit

30

, and withdraws from the cooling unit

30

after delivering the wafer W, which has been transported from a different treating unit, to a delivery position (e.g. on the three support pins

32

) inside the cooling unit

30

. At this time, the plate

51

of the local transport mechanism

50

is placed in the standby position adjacent the bottom in the cooling unit

30

. When the first main transport mechanism TR

1

loads the wafer W on the support pins

32

in the cooling unit

30

, the first main transport mechanism TR

1

never contacts the plate

51

of the local transport mechanism

50

in the standby position, or the local transport mechanism

50

never obstructs the loading operation. The main transport mechanism access opening

34

of the cooling unit

30

is closed after the first main transport mechanism TR

1

withdraws therefrom. The cooling unit

30

keeps the wafer W on standby. In the cooling unit

30

, the wafer W is cooled, as necessary, during the standby.

(12) Receipt of Wafer W by the Local Transport Mechanism

50

:

Upon completion of the cooling treatment of the wafer W by the cooling unit

30

, as shown in

FIG. 12B

, the vertical moving mechanism

60

of the local transport mechanism

50

is driven to raise the plate

51

and pick up the wafer W supported on the three support pins

32

. Then, the local transport mechanism access opening

35

of the cooling unit

30

is opened. As shown in

FIG. 12C

, the horizontal moving mechanism

70

of the local transport mechanism

50

is driven to move the plate

51

in y-direction out of the cooling unit

30

. After the plate

51

of the local transport mechanism

50

moves outside, the access opening

35

of the cooling unit

30

is closed.

(13) Loading of Wafer W into the Heating Unit

40

by the Local Transport Mechanism

50

:

As shown in

FIG. 13A

, the vertical moving mechanism

60

of the local transport mechanism

50

is driven to lower the plate

51

to a level for loading the wafer W into the heating unit

40

. Then, the local transport mechanism access opening

45

of the heating unit

40

is opened. As shown in

FIG. 13B

, the horizontal moving mechanism

70

of the local transport mechanism

50

is driven to move the plate

51

in y-direction into the heating unit

40

. As shown in

FIG. 13C

, the vertical moving mechanism

60

is driven to lower the plate

51

to a wafer delivery level to deliver the wafer W to a delivery position (e.g. on the three support pins

42

) inside the heating furnace

41

of the heating unit

40

. Alternatively, the support pins

42

of the heating unit

40

are raised to receive the wafer W. Then, the horizontal moving mechanism

70

is driven to withdraw the plate

51

in y-direction out of the heating unit

40

. The plate

51

of the local transport mechanism

50

is further moved in an operation reversed from the foregoing operation. Ultimately, the plate

51

is placed in the standby position adjacent the bottom surface inside the cooling unit

30

as shown in FIG.

12

A. The local transport mechanism access opening of the heating unit

40

is closed after the plate

51

of the local transport mechanism

50

leaves the heating unit

40

.

(14) Heating of Wafer W by the Heating Unit

40

:

As shown in

FIG. 14A

, the heating furnace

41

lowers the top cover

41

b

to close the opening of the container body

41

a,

and lowers the support pins

42

to place the wafer W on the upper surface of hot plate

41

c.

In this state, the wafer W receives a predetermined heating treatment in the heating furnace

41

. After the heating treatment, the heating furnace

41

raises the top cover

41

b

to open the opening of the container body

41

a,

and raises the support pins

42

to support the wafer W in a position away from the upper surface of hot plate

41

c.

As noted hereinbefore, the heating treatment may be performed to bake the wafer W after a bottom coating is formed thereon in the BARC unit, to bake the wafer W after a photoresist film is formed thereon in the SC unit, to bake the wafer W after exposure, i.e. PEB treatment, or to bake the wafer W after development.

(15) Reloading of Wafer W into the Cooling Unit

30

by the Local Transport Mechanism

50

:

The plate

51

of the local transport mechanism

50

is moved from the standby position in the cooling unit

30

into the heating unit

40

. The plate

51

picks up and holds the wafer W supported by the three support pins

42

raised after the heating treatment in the heating furnace

41

, and transports the heated wafer W onto the three support pins

32

in the cooling unit

30

. Then, the plate

51

of the local transport mechanism

50

is placed in the standby position adjacent the bottom surface inside the cooling unit

30

.

(16) Unloading of Wafer W from the Cooling Unit

30

by the First Main Transport Mechanism TR

1

:

The main transport mechanism access opening

34

of the cooling unit

30

is opened as the first main transport mechanism TR

1

approaches the access opening

34

. As shown in

FIG. 14B

, the first main transport mechanism TR

1

enters the access opening

34

of the cooling unit

30

. The first main transport mechanism TR

1

picks up and holds the wafer W supported by the three support pins

32

in the cooling unit

30

, then withdraws from the cooling unit

30

, and transports the wafer W to a predetermined different treating unit.

The operation of the first main transport mechanism TR

1

for transporting the wafer W described in sections (11) and (16) above corresponds to the main transport step. The operation of the local transport mechanism

50

for transporting the wafer W described in sections (12), (13) and (14) above corresponds to the local transport step. The standby of the local transport mechanism

50

in the standby position inside the cooling unit

30

described in sections (11), (15) and (16) above corresponds to the standby step.

According to the substrate treating apparatus in the second embodiment, as described above, the local transport mechanism

50

, when on standby, is placed in the standby position inside the cooling unit

30

of the heat-treating unit

20

. Consequently, the local transport mechanism

50

is less influenced by the environment outside the heat-treating unit

20

than where the local transport mechanism

50

kept on standby outside the heat-treating unit

20

. The local transport mechanism

50

on standby influences the environment outside the heat-treating unit

20

to a reduced degree. Variations in substrate treating precision due to such adverse influences may be reduced to perform substrate treatment with high precision. Further, temperature control of the local transport mechanism

50

may be effected easily. The local transport mechanism

50

capable of transferring wafers W between the cooling unit

30

and heating unit

40

in the heat-treating unit

20

lightens the burden on the first main transport mechanism TR

1

.

In the conventional substrate treating apparatus, the local transport mechanism of each heat-treating unit (heat-treating unit among the treating units

104

in

FIG. 1

) remains protruding from this heat-treating unit in a normal state, and temporarily enters the heat-treating unit only in time of substrate transport. The conventional substrate treating apparatus has poor maintenability since the local transport mechanism protruding from the heat-treating unit is obstructive to movement of the interface or the like. However, in the substrate treating apparatus in the second embodiment, the local transport mechanism

50

of the heat-treating unit

20

moves out of the heat-treating unit

20

only temporarily, that is only when transporting wafers W. In a normal state other than the time of transporting wafers W, the local transport mechanism

50

does not protrude from the heat-treating unit

20

. Thus, the substrate treating apparatus in the second embodiment has excellent maintenability in that the interface

4

or the like may be moved without obstruction.

The cooling unit

30

has the access opening

35

for the local transport mechanism

50

separately from the access opening

34

for the first main transport mechanism TR

1

. This arrangement reduces the chance of interference between the local transport mechanism

50

and the first main transport mechanism TR

1

.

Further, the first main transport mechanism TR

1

accesses only the cooling unit

30

of the heat-treating unit

20

, while the local transport mechanism

50

accesses the cooling unit

30

and heating unit

40

of the heat-treating unit

20

. This provides a thermal separation between the first main transport mechanism TR

1

and local transport mechanism

50

.

Furthermore, the first main transport mechanism TR

1

accesses only the cooling unit

30

acting as a specific substrate treating section in the heat-treating unit

20

. That is, the first main transport mechanism TR

1

delivers a wafer W to the cooling unit

30

of the heat-treating unit

20

, and takes the wafer W out of this cooling unit

30

. It is unnecessary to move the heat-treating unit

20

or first main transport mechanism TR

1

up and down. Thus, the heat-treating unit

20

and first main transport mechanism TR

1

may have simple constructions.

This invention is not limited to the foregoing embodiments, but may be modified as follows:

(1) In the first embodiment described hereinbefore, the first main transport mechanism TR

1

transports a wafer W from a different treating unit to the cooling unit

30

of the heat-treating unit

20

, the local transport mechanism

50

transports the wafer W from the cooling unit

30

to the heating unit

40

of the same heat-treating unit

20

, and the second main transport mechanism TR

2

transports the wafer W from the heating unit

40

to a different treating unit. Conversely, the second main transport mechanism TR

2

may transport the wafer W from a different unit to the heating unit

40

of the heat-treating unit

20

, the local transport mechanism

50

transporting the wafer W from the heating unit

40

to the cooling unit

30

of the same heat-treating unit

20

, and the first main transport mechanism TR

1

transporting the wafer W from the cooling unit

30

to a different treating unit. In this case also, the standby position of the plate

51

of the local transport mechanism

50

is provided inside the cooling unit

30

as in the first embodiment. The plate

51

of the local transport mechanism

50

is placed in the standby position inside the cooling unit

30

, in the normal state not transporting the wafer W from the heating unit

40

to the cooling unit

30

.

(2) In the second embodiment described hereinbefore, the first main transport mechanism TR

1

transports a wafer W from a different treating unit to the cooling unit

30

of the heat-treating unit

20

, the local transport mechanism

50

transports the wafer W between the cooling unit

30

and heating unit

40

of the same heat-treating unit

20

, and the first main transport mechanism TR

1

transports the wafer W from the cooling unit

30

to a different treating unit. Conversely, the first main transport mechanism TR

1

may transport the wafer W from a treating different unit to the heating unit

40

of the heat-treating unit

20

, the local transport mechanism

50

transporting the wafer W between the heating unit

40

and cooling unit

30

of the same heat-treating unit

20

, and the first main transport mechanism TR

1

transporting the wafer W from the heating unit

40

to a different treating unit. In this case also, the standby position of the plate

51

of the local transport mechanism

50

is provided inside the cooling unit

30

as in the second embodiment. The plate

51

of the local transport mechanism

50

is placed in the standby position inside the cooling unit

30

, in the normal state not transporting the wafer W between the heating unit

40

and cooling unit

30

.

(3) The plate

51

of the local transport mechanism

50

in each of the foregoing embodiments may, as shown in

FIG. 15

, include a substrate cooler

56

for cooling a wafer W on the plate

51

. The substrate cooler

56

has a coolant source

57

for supplying a coolant (e.g. a cooling gas or cooling liquid), and a coolant passage

58

extending along a predetermined course in the plate

51

for circulating the coolant from the coolant source

57

. The substrate cooler

56

cools the wafer W supported on the plate

51

. This substrate cooler

56

corresponds to the substrate cooling device of this invention. With this construction, the local transport mechanism

50

not only transports the wafer W, but can start cooling the wafer W upon receipt thereof.

(4) In each of the foregoing embodiments, the heat-treating unit

20

has the heating unit

40

disposed below the cooling unit

30

. Conversely, the heat-treating unit may have the cooling unit

30

disposed below the heating unit

40

.

(5) In each of the foregoing embodiments, the heat-treating unit

20

includes the cooling unit

30

and heating unit

40

. Instead, the heat-treating unit may include a standby unit and the heating unit

40

. The standby unit in this case has a space for keeping a substrate on standby, and effecting a natural cooling of the substrate on standby. This corresponds to the cooling unit

30

without the cooler

31

in the first and second embodiments. This standby unit corresponds to the substrate treating section and further to the substrate standby section of this invention. In this case, the local transport mechanism

50

may include the substrate cooler

56

shown in FIG.

15

. Then, the local transport mechanism

50

can cool a heated substrate in the standby unit.

(6) In each of the foregoing embodiments, the cooler

31

may be driven to cool positively the plate

51

of the local transport mechanism

50

placed in the standby position inside the cooling unit

30

of the heat-treating unit

20

. The above cooler

31

corresponds to the cooling device of this invention. Thus, the plate

51

of the local transport mechanism

50

may be cooled while on standby inside the cooling unit

30

. The cooler

31

may be provided in the standby unit noted above, for positively cooling the plate

51

of the local transport mechanism

50

placed in the standby position inside the standby unit.

(7) In each of the foregoing embodiments, the heat-treating unit

20

includes the cooling unit

30

and heating unit

40

. Instead, the heat-treating unit may include a plurality of heating units. In this case, one of the heating units provides a standby position therein for keeping the plate

51

of the local transport mechanism

50

on standby. The standby position is set so that the plate

51

of the local transport mechanism

50

on standby does not interfere with the main transport mechanism (the first main transport mechanism TR

1

or second main transport mechanism TR

2

) accessing the heating unit.

(8) In each of the foregoing embodiments, the heat-treating unit

20

includes the cooling unit

30

and heating unit

40

. Instead, the heat-treating unit may include a plurality of cooling units. In this case, one of the cooling units provides a standby position therein for keeping the plate

51

of the local transport mechanism

50

on standby, as in the first embodiment.

(9) In each of the foregoing embodiments and modifications, as shown in

FIGS. 4 and 15

, the plate

51

of the local transport mechanism

50

is placed opposite the undersurface of wafer W to support the wafer W. The invention is not limited to such substrate holding mechanism of the local transport mechanism

50

. For example, the plate

51

may be replaced by an arm

59

as shown in

FIG. 16

, to act as the substrate holding mechanism of the local transport mechanism

50

. This arm

59

includes an arcuate portion extending along the edge of a wafer W in plan view. The arm

59

holds the wafer W by supporting it at the edge thereof. In this case, the arm

59

is positioned only at the undersurface of wafer W, particularly at the edge of wafer W. Thus, the plate

51

and arm

59

in various forms may be employed as the substrate holding mechanism of the local transport mechanism

50

.

(10) In each of the foregoing embodiments, substrate treatment is exemplified by resist application and development in a photolithographic process. The invention is not limited to such examples of substrate treatment. The invention is applicable to any substrate treatment performed in a usual manner on substrates such as semiconductor wafers, glass substrates for liquid crystal displays, glass substrates for photomasks, and substrates for optical disks. Such treatment may, for example, be a chemical treatment in which substrates are immersed in a treating solution and which includes cleaning and drying, an etching process of the non-immersion type (e.g. dry etching, plasma etching and so on), a cleaning treatment of the non-immersion type for cleaning substrates in a spin (e.g. sonic cleaning, chemical cleaning, and so on), chemical machine polishing (CMP), sputtering, chemical vapor deposition (CVD), or ashing.

This invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention.

Number	Name	Date	Kind
5015177	Iwata	May 1991	A
5651823	Parodi et al.	Jul 1997	A
5935768	Biche et al.	Aug 1999	A

Substrate treating apparatus

Information

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CPC

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Abstract

Description

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Priority Claims (1)

US Referenced Citations (3)