Patent Application
20220341053
The present invention relates to a plating machine used for plating a wafer with Cu and the like.
Recently, as a production line for semiconductor devices which uses such a plating machine, a layout based on. a job shop system has been mainly employed. In the job shop system, a plurality of units, which is referred to as bays in which the semiconductor processing machines having the same kind of functions are collectively arranged, is provided within a large clean room, and the bays are connected to each other via a robot for conveyance or a belt conveyor. As a work to be processed in the production line described above, a large diameter wafer having the diameter of, for example, 12 inches is used, and thousands of semiconductor chips are obtained from a single wafer.
However, in this job shop system, in the case where a plurality of similar processes is repeated, conveyance distances inside a bay and/or among the bays increase, and waiting time increases accordingly. This causes increased production time and/or increased products in progress, which results in an increased cost, and especially in the production line for producing a large number of semiconductor chips, causes a problem of low productivity. In view of this problem, a production line based on a flow shop system in which the semiconductor processing machines are arranged in the order of processes has been proposed instead of the conventional production line based on the job shop system.
The production line based on the flow shop system is suitable for the case of producing a large number of the same products, however, in the case of producing other products, it is necessary to change a production procedure (recipe) and also rearrange the installation location of each. semiconductor processing machines in the production line in accordance with the order of the processing flow of the semiconductor chips to be produced. However, in view of efforts and time, rearrangement of the semiconductor processing machines at every change of the semiconductor chips to be processed is not practical. Especially, considering that huge semiconductor processing machines are installed and fixed in a clean room which is a closed space, it is practically impossible to rearrange the semiconductor processing machines in each case.
Furthermore, there is also a demand of production of very low volume of semiconductors whose production unit is from a few to several hundred, which are, for example, engineer samples and ubiquitous sensors. However, producing very low volume of semiconductors in a huge production line based on the on shop system or the flow ship system described above causes a remarkable deterioration of cost efficiency. Accordingly, in this case, different semiconductors need to be produced in the same production line.
However, producing different semiconductors at the same time causes a reduction in productivity of the production Line which becomes worse with an increase in the number of varieties of the semiconductors to be produced. Thus, the huge production line is not suitable for very low-volume and high-mix production.
In a plating machine used in this type of production line, a guide rail is arranged in a substantially eliptical shape, and treatment units for plating a plate-shaped object such as a printed circuit board, which are, for example, a pre-treatment tank, a plating tank., and a water washing tank, are arranged side by side along the guide rail. This plating machine is designed to move the plate-shaped object along the guide rail so that the plate-shaped object can be sequentially conveyed to the pre-treatment tank, the plating tank, the water washing tank, and the like, whereby the processes by the pre-treatment tank, the plating tank, the water washing tank, and the like are sequentially performed (for example, see Patent Literature 1).
Patent Literature 1: JP-A-2002-363796
In the above-described prior art disclosed in Patent Literature 1, the plate-shaped object is moved along the guide rail so as to be sequentially conveyed to the pre-treatment tank, the plating tank, the water washing tank, and the like, whereby the processes of plating the plate-shaped object are continuously performed. In order to sequentially convey the plate-shaped object to the pre-treatment tank, the plating tank, the water washing tank, and the like, these tanks are required to be arranged side by side along the guide rail, which makes the structure necessary for conveying the plate-shaped object complex.
The present invention has been made in view of the above-described actual circumstances of the prior art, and an object thereof is to provide a plating machine capable of conveying a wafer with a simple structure.
In order to achieve the object above, the present invention provides a plating machine comprising: a plurality of treatment units; and a conveying means that conveys a wafer to the plurality of treatment units, the conveying means including an arm that is provided, on one end side, with a holding unit that holds the wafer, and an arm rotation drive unit that rotates the arm around another end side of the arm, and the plurality of treatment units being arranged at predetermined intervals on a rotation trajectory of the holding unit.
According to the present invention having the structure described above, the plurality of treatment units is arranged at predetermined intervals on the rotation trajectory of the holding-unit which can be obtained by the rotation of the arm, and accordingly, through a simple operation of rotating the arm by the arm rotation drive unit, it is possible to convey the wafer held by the holding unit to the plurality of treatment units.
In order to achieve the object above, in the present invention, the conveying means includes a vertical movement drive unit that moves the holding unit upward and downward.
According to the present invention having the structure described above, the vertical movement drive unit moves the holding unit upward and downward, and accordingly, it is possible to carry the wafer held by the holding unit in and out from the plurality of treatment units.
In order to achieve the object above, in the present invention, the holding unit is rotatably supported around an axis thereof by the arm, and the conveying means includes a wafer rotation drive unit that rotates the holding unit around the axis thereof.
According to the present invention having the structure described above, the wafer rotation drive unit rotates the holding unit around the axis thereof so that the wafer held by the holding unit can be rotated around the axis thereof, and accordingly, it is possible to drain, for example, the liquid adhering to the wafer or dry the wafer.
In order to achieve the object above, in the present invention, a stage on which the wafer is delivered is provided, and the stage includes a wafer reversing unit that reverses the wafer delivered on the stage and conveys the wafer which has been reversed to the holding unit of the conveying means.
In order to achieve the object above, in the present invention, the wafer delivered on the stage is reversed by the wafer reversing unit and then conveyed to the holding unit of the conveying means, and accordingly, for example, even when, at the time of being delivered on the stage, a surface to be plated is positioned on the upper side of the wafer, the wafer can be conveyed to each of the treatment units after being turned over. As a result, it is possible to easily plate a wafer even in a tank-shaped treatment unit filled with, for example, the plating solution.
In order to achieve the object above, in the present invention, the wafer has a surface to be treated on one of upper and lower sides, the wafer is delivered on the stage with the surface to be treated facing upward, the wafer reversing unit reverses the wafer delivered on the stage and conveys the wafer to the holding unit with the surface to be treated facing downward, and the plurality of treatment units performs treatment on the surface to be treated of the wafer which has been facing downward.
According to the present invention having the structure described above, the wafer which has been delivered to the stage with the surface to be treated facing upward is turned over by the wafer reversing unit and conveyed to the holding unit of the conveying means with the surface to be treated facing downward, and accordingly, it is possible to prevent damage to the surface to be treated of the wafer until the wafer is conveyed from the stage to the holding unit of the conveying means. Furthermore, the plurality of treatment units performs processes on the surface to be treated of the wafer facing downward, which means that the plurality of treatment units performs the processes only on the surface to be treated on the lower side of the wafer, and accordingly, it is possible to simplify the processes for the wafer performed by the plurality of units.
In order to achieve the object above, in the present invention, the wafer is formed into a disc-shape having an outside diameter of 12.5 mm.
According to the present invention having the structure described above, the wafer is formed into a disc shape having the outside diameter of 12.5 mm, and accordingly, the wafer is the one used in a so-called minimal fab system.
According to the present invention, a plurality of treatment units is arranged at predetermined intervals on rotation trajectory of a holding unit, and therefore, it is possible to convey a wafer held by the holding unit to the plurality of treatment units through a simple operation of rotating an arm.
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
A plating machine 1 according to one embodiment of the present invention is used for plating, with Cu and the like, a surface B to be treated which is a surface of a wafer W. As illustrated in
As illustrated. in
As illustrated in
The front chamber 2d is designed to block the entry of fine particles and gas molecules into the housing 2. That is, the front chamber 2d houses a PLAD (Particle Lock Air-tight Docking) system 9 serving as a conveying device which carries the wafer W installed in the shuttle in and out from the housing 2 without letting the wafer W to be exposed to the outside air. The PLAD system 9 is designed to carry the wafer W, which has been conveyed from the docking port 2e with the surface B to be treated facing upward, to a predetermined position of the plating machine 1, and carry out the wafer W after being plated by the plating machine 1 to the docking port 2e.
As illustrated in
The housing lower portion 2b houses, for example, control device (not illustrated) for controlling the plating machine 1 provided in the housing upper portion 2a, various chemical solution tanks for storing treatment liquids used by the plating machine 1 such as a plating solution M, pure water, and a post-treatment solution, and a drain tank (not illustrated). Furthermore, as illustrated in
The wafer W to be plated by the plating machine 1 includes a circular surface having a predetermined size, for example, which is 12.5 mm (half-inch size), and is formed in a disc shape composed of single crystal silicon (Si). A predetermined pattern is formed on a surface of the wafer W, which is the surface B to be treated before being plated. The plating machine 1 plats only the surface B to be treated of the wafer W.
Specifically, as illustrated in
As illustrated in
As illustrated in
The reversing arm 23 of the wafer reversing mechanism 22 is mounted, in a state of waiting for the wafer W to be delivered on the stage 12, such that the distal end side thereof is inserted into the insertion recess 12a of the stage 12. The reversing arm 23 can be rotated around the proximal end side thereof by the rotation drive unit 25, and furthermore, can be moved upward and downward in the vertical direction by the vertical movement drive unit 26.
The suction pad 24 is a so-called vacuum chuck, and is mounted to the distal end portion of a support piece 23a which is mounted. at the right angle to the distal end side of the reversing arm 23. Furthermore, as illustrated in
The conveying means 13 houses the wafer W that has been turned over by the wafer reversing mechanism 22, and conveys the wafer W sequentially to the plurality of treatment units 14. Specifically, as illustrated in
The arm rotation drive unit 33 rotates and drives the conveying arm 31 around the other end side of the conveying arm 31 in an arc within a predetermined angle range. In other words, the arm rotation drive unit 33 moves the conveying arm 31 in an arc in a horizontal plane, and for example, formed with a robot rotary. On the arm rotation drive unit 33, the arm vertical movement drive unit 34 is mounted, and the proximal end side of the conveying arm 31 is connected to the arm vertical movement drive unit 34 is that the conveying arm 31 can be moved in the vertical direction, namely, upward and downward.
The wafer rotation drive unit 35 is mounted to the upper side of the distal end portion of the conveying arm 31, and for example, is formed with a motor. The wafer rotation drive unit 35 rotates and drives a rotary shaft 36 serving as a cylindrical support assembly, which projects downward from the lower surface of the distal end portion of the conveying arm 31, in the circumferential direction. The holder 32 is supported around an axis thereof by the rotary shaft 36, and when the wafer rotation drive unit 35 rotates the rotary shaft 36 therearound, the holder 32 is rotated around the center position thereof.
The holder 32 is mounted to one end side of the conveying arm 31, and as illustrated in
The side surface of the housing recess 41 includes a pressure adjustment hole 44 for equalizing the pressure in the housing recess 41 and the pressure outside the housing recess 41. Furthermore, on the opening edge of the housing recess 41, a disc-shaped covering piece member 45 which projects outward from the outer peripheral surface of the housing recess 41 is mounted concentrically. On the outer peripheral edge of the covering piece member 45, an annular circumferential surface member 46 that projects upward is mounted concentrically. Furthermore, on an intermediate position in the vertical direction of the circumferential surface member 46, an engagement recess 47 serving as a locking member having a recessed cross-section is mounted over the circumferential direction of the circumferential surface member 46. Inside the circumferential surface member 46, a magnetic assembly 48 formed with, for example, iron is provided. The magnetic assembly 48 is provided with, at a center position. thereof, an opening 49 having a circular shape that is substantially equal to the inside diameter of the housing recess 41, and is formed in an annular shape having the outside diameter substantially equal to the inside diameter of the circumferential surface member 46.
As illustrated in
On the peripheral surface of the insertion projection 51, an O-ring 53 for sealing the inner peripheral surface of the housing recess 41 and the outer peripheral surface of the insertion projection 51 is mounted. The O-ring 53 seals the inside of the housing recess 41 in a state where the insertion projection 51 is inserted into the housing recess 41. Therefore, the O-rings 43, 53 serve as a sealing means for sealing the space in the housing recess 41 in a state where the wafer is placed on the bottom surface of the housing recess 41 and the insertion projection is inserted into the housing recess 41.
Furthermore, the upper end of the insertion projection 51 is provided with a concentrical disc-shaped support piece member 54 that is substantially equal to the outside diameter of the circumferential surface member 46 of the lower part 37. On the lower surface of the support piece member 54, an annular magnet assembly 55 is embedded and mounted concentrically. The magnet assembly 55 is mounted such that its lower surface is made flush with the lower surface of the support piece member 54. On the upper surface side of the support piece member 54, the lower end of the rotary shaft 36 of the wafer rotation drive unit 35 is fixed and mounted concentrically. Thus, the magnetic assembly 48 and the magnet assembly 55 serve as an integrating means for removably integrating the lower part 37 with the upper part 38.
The plurality of treatment units 14 is arranged at predetermined intervals on the rotation trajectory of the holder 32 which is obtained in accordance with the rotation drive by the reversing arm 23 of the conveying means 13. The pre-treatment unit 14a includes a pre-treatment tank 61 which is a bottomed cylindrical treatment tank filled with the plating solution M as a treatment liquid. The pre-treatment tank 61 has the inside diameter larger than the outside diameter of the housing recess 41 of the lower part 37 of the holder 32. The pre-treatment tank 61 is filled with the plating solution M, and the lower end side of the housing recess 41 of the holder 32 is immersed in the plating solution M. In this state, in the pre-treatment tank 61, the pre-treatment process is performed for the surface B to be treated of the wafer 4 which is exposed through the opening 42 of the housing recess 41 of the holder 32, for example, to remove air bubbles in the plating solution M adhering to the surface B to be treated of the wafer W.
As illustrated in
Furthermore, as illustrated in
As illustrated in
As illustrated in
The post-treatment unit 14d is designed substantially in the same manner as the water washing unit 14c, and includes a post-treatment tank 74 which is a bottomed cylindrical treatment tank having the inside diameter larger than the outside diameter of the housing recess 41 of the holder 32. The post-treatment tank 74 is provided with an opening 75 at the center position of the lower surface thereof. On the opening 75, a post-treatment solution supply mechanism (not illustrated) for supplying the post-treatment solution that is a treatment liquid is mounted. Here, as the post-treatment solution, for example, an anti-rust treatment material for covering a protective film, such as an organic film, on the plating layer formed on the surface B to be treated of the wafer W is used. In the post-treatment unit 14d, the post-treatment solution supply mechanism supplies the post-treatment solution into the post-treatment tank 74 through the opening 75 so as to form the protective film on the plating layer formed on the surface B to be treated of the wafer W which has been inserted into the post-treatment tank 74. When the post-treatment solution supplied in the post-treatment tank 74 overflows from the post-treatment tank 74, the overflown solution is discharged to the outside of the plating chamber 11 from the drain port 73 provided around the post-treatment tank 74.
The drying unit 14e includes a drying tank 76 which is a bottomed cylindrical treatment tank having the inside diameter larger than the outside diameter of the housing recess 41 of the holder 32. The drying tank 76 is provided with an opening 77 at the center position. of the lower surface thereof, and on the opening 77, a warm air supply mechanism. (not illustrated) for supplying warm air of, for example, 45° C. is mounted. The warm air supply mechanism supplies the warm air into the drying tank 76 through the opening 77 to dry the protective film on the surface B to be treated of the wafer W which has been inserted into the drying tank 76.
As illustrated. in
As illustrated in
Hereinafter, a plating method using the plating machine 1 according to the embodiment described above will be explained.
Firstly, the shuttle in which the wafer W is housed with the surface B to be treated facing upward is fitted to the docking port 2e of the front chamber 2d of the housing 2, and installed thereon. In this state, a start switch which is, for example, displayed on a predetermined position of the housing 2, such as the operation panel 2c, is turned on (not illustrated).
In response thereto, the fan 2g attached. to the upper portion of the housing 2 is driven, whereby the air out the housing 2 is sucked from the air vent 2f, particles contained in the air sucked from the air vent 2f are captured by the air filter 2h, and the air of which the particles has been removed is supplied to the housing 2. At the same time, the scrubber 2j mounted to the lower portion of the housing 2 is driven, whereby the air floating in the chemical floating region 82 of the plating chamber 11 is forcibly sucked from the suction port 67 and discharged from the discharge outlet 2k to the outside of the housing 2. At this time, as illustrated in
Thereafter, the shuttle installed on the docking port 2e is released. Then, the wafer N housed in the shuttle, with the surface B to be treated facing upward, is conveyed by the PLAD system 9 onto the stage 12 in the plating chamber 11 as illustrated in
Next, the vertical movement drive unit 26 of the wafer reversing mechanism 22 moves the reversing arm 23 upward to bring the lower surface of the wafer W into contact with the suction pad 24 and make the wafer W sucked thereto. Thereafter, as illustrated in
In this state, the rotation drive unit 25 rotates the reversing arm 23 by 180 degrees around the proximal end side of the reversing arm 23. As a result, as illustrated in
Next, as illustrated in
Thereafter, as illustrated in
Thereafter, the arm rotation drive unit 33 rotates the conveying arm 31 in an arc to convey the holder 32 onto the plating tank 62. At this time, as illustrated in
Then, in a state where the circulation mechanism 66 keeps circulating the plating solution M in the plating tank 62, the arm vertical movement drive unit 34 moves the holder 32 downward to immerse the surface B to be treated of the wafer W which is exposed from the opening 42 of the lower part 37 of the holder 32 in the plating solution M of the plating tank 62. At this time, as illustrated in
In this state, the wafer rotation. drive unit 35 rotates the holder 32 in the circumferential direction, and the wafer W is supplied with. power from the electrode unit 52 of the upper part 38 of the holder 32 to generate a potential difference between the wafer W and the plating tank 62, whereby a plating layer formed on the surface B to be treated of the wafer W. Thereafter, the arm vertical movement drive unit 34 moves the holder 32 upward to take the surface B to be treated which is exposed through the opening 42 of the lower part 37 of the holder 32 out from the plating solution M in the plating tank 62. Then, the wafer rotation drive unit 35 rotates the holder 32 at high speed in the circumferential direction to drain the plating solution M adhering to the surface B to be treated of the wafer W.
Thereafter, the arm rotation drive unit 33 rotates the conveying arm 31 in an arc to convey the holder 32 onto the water washing tank 71. In this state, the arm vertical movement drive unit 34 moves the holder 32 downward to bring the surface B to be treated of the wafer W which is exposed through the opening 42 of the lower part 37 of the holder 32 into the water washing tank 71. Then, the pure water supply mechanism supplies the pure water into the water washing tank 71 through the opening 72 of the water washing tank 71, and also the wafer rotation drive unit 35 rotates the holder 32 in the circumferential direction so as wash the plating layer formed on the surface B to be treated of the wafer W with the pure water. At this time, the pure water which overflows from the water washing tank 71 is discharged to the outside of the plating chamber 11 through the drain port 73.
Thereafter, the arm vertical movement drive unit 34 moves the holder 32 upward to take the surface B to be treated which is exposed through the opening 42 of the lower part 37 of the holder 32 out from the water washing tank 71. Then, the wafer rotation drive unit 35 rotates the holder 32 at high speed in the circumferential direction to drain the pure water adhering to the plating layer formed on the surface B to be treated of the wafer W.
Furthermore, the arm rotation drive unit 33 rotates the conveying arm 31 in an arc to convey the holder 32 onto the post-treatment tank 74. In this state, the arm vertical movement drive unit 34 moves the holder 32 downward to immerse the surface B to be treated of the wafer W which is exposed through the opening 42 of the lower part 37 of the holder 32 into the post-treatment solution filling the post-treatment tank 74. At this time, the wafer rotation drive unit 35 rotates the holder 32 in the circumferential direction to make the post-treatment solution adhering to the plating layer formed on the surface B to be treated of the wafer W.
Thereafter, the arm vertical movement drive unit 34 moves the holder 32 upward to take the surface B to be treated which is exposed through the opening 42 of the lower part 37 of the holder 32 out from the post-treatment solution in the post-treatment tank 74. Then, the wafer rotation drive unit 35 rotates the holder 32 in the circumferential direction to form a protective film by drying and curing the post-treatment solution adhering to the plating layer of the wafer W.
Next, the arm rotation drive unit 33 rotates the conveying arm 31 in an arc to convey the holder 32 onto the water washing tank 71, and the arm vertical movement drive unit 34 moves the holder 32 downward to insert the lower end of the holder 32 into the water washing tank 71. Thereafter, the pure water supply mechanism supplies the pure water through the opening 72 of the water washing tank 71 into the water washing tank 71, and the wafer rotation drive unit 35 rotates the holder 32 in the circumferential direction so as to wash the protective film of the wafer W with water.
Thereafter, the arm vertical movement drive unit 34 moves the holder 32 upward to take the surface B to be treated which is exposed through the opening 42 of the lower part 37 of the holder 32 out from the water washing tank 71. Then, the wafer rotation drive unit 35 rotates the holder 32 at high speed in the circumferential direction so as to drain the pure water adhering to the protective film of the wafer W.
Next, the arm rotation drive unit 33 rotates the conveying arm 31 in an arc to convey the holder 32 onto the drying tank 76. In this state, the arm vertical movement drive unit 34 moves the holder 32 downward to insert the surface B to be treated of the wafer W which is exposed through the opening 42 of the lower part 37 of the holder 32 into the drying tank 76. Thereafter, the warm air supply mechanism supplies the warm air to the drying tank 76 through the opening 77 of the drying tank 76, and the wafer rotation drive unit 35 rotates the holder 32 at high speed in the circumferential direction so as to dry the wafer W.
At this time, as illustrated in
Thereafter, the arm vertical movement drive unit 34 moves the holder 32 upward to take the surface B to be treated which is exposed through the opening 42 of the lower part 37 of the holder 32 out from the drying tank 76.
Next, the arm rotation drive unit 33 rotates the conveying arm 31 in an arc to convey the holder 32 onto the wafer housing unit 14f. Thereafter, as illustrated in
In this state, the vertical movement drive unit 26 of the wafer reversing mechanism 22 moves the reversing arm 23 upward, and then. the rotation drive unit 25 rotates the reversing arm 23 by 180 degrees around the proximal end side of the reversing arm 23. Thereafter, the vertical movement drive unit 26 moves the reversing arm 23 downward so as to, as illustrated in
Thereafter, the PLAD system 9 carries out the wafer W placed on the stage 12 to place the wafer W on the shuttle installed in the docking port 2e. The shuttle is closed to house the wafer W, and removed from the docking port 2e of the front chamber 2d, whereby the wafer W is carried out.
As described. above, in the plating machine 1 according to the embodiment, on the rotation trajectory of the center position of the holder 32 which is obtained by the arcuate rotation of the conveying arm 31 by the arm rotation drive unit 33, each of the plurality of treatment units 14, namely, the pre-treatment tank 61, the plating tank 62, the water washing tank 71, and the post-treatment tank 74, and the wafer housing unit 14f that is a standby port of the lower part 37 of the holder 32 are arranged at the predetermined intervals. The wafer W is placed on the housing recess 41 of the lower part 37 installed. on the wafer housing unit 14f, and then the arm vertical movement drive unit 34 moves the upper part 38 downward. to immerse the insertion projection 51 of the upper part 38 into the housing recess 41 of the lower part 37, whereby the lower part 37 is integrated with the upper part 38 to be the holder 32. With a simple structure and through a simple operation. in which the arm rotation drive unit 33 rotates the conveying arm 31 in an arc in the state above, it is possible to convey the wafer W held by the holder 32 sequentially with a relatively short moving distance to each of the pre-treatment tank 61, the plating tank 62, the water washing tank 71, and the post-treatment tank 74. Furthermore, through the rotary operation of the holder 32 interlocked with the convey operation of the wafer W to the pre-treatment tank 61, the plating tank 62, the water washing tank 71, and the post-treatment tank 74, it is possible to carry the holder 32 in and out from the wafer housing unit 14f.
In particular, the wafer W is placed on the bottom surface of the housing recess 41 of the lower part 37 of the holder 32 with the surface B to be treated facing downward, so that the surface B to be treated of the wafer W is exposed through the opening 42 of the housing recess 41. In this state, the insertion projection 51 of the upper part 38 is inserted into the housing recess 41 of the lower part 37 to integrate the lower part 37 with the upper part 38, whereby the wafer W is sandwiched between the insertion projection 51 of the upper part 38 and the opening edge of the housing recess 41 of the lower part 37. Then, since the arm vertical movement drive unit 34 moves the holder 32 downward to immerse the lower end of the housing recess 41 of the lower part 37 of the holder 32, for example, in the plating solution M in the plating tank 62, it is possible to accurately and reliably immerse the surface B to be treated which is exposed through the opening 42 of the lower part 37 of the holder 32 into the plating solution M. Thus, it is possible to accurately and reliably plate the surface B to be treated of the wafer W.
Furthermore, in the state where the wafer W is placed on the bottom surface of the housing recess 41 of the lower part 37 of the holder 32, the insertion projection 51 of the upper part 38 is inserted into the housing recess 41 to integrate the lower part 37 with the upper part 38, whereby the electrode unit 52 of the upper part 38 is brought in contact with the top surface of the wafer W and energizes the wafer W. Thus, only through a series of operations of placing the wafer W on the housing recess 41 of the lower part 37 of the holder 32 and inserting the insertion projection 51 of the upper part 38 into the housing recess 41, it is possible to easily secure an electrode for the wafer W, which is required during the plating process.
Furthermore, after the wafer W is placed on the bottom surface of the housing recess 41 of the lower part 37 of the holder 32 with the surface B to be treated of the wafer W facing downward so that the surface B to be treated of the wafer W is exposed through the opening 42 of the lower part 37 of the holder 32, the arm rotation drive unit 33 rotates the conveying arm 31 in an arc to convey the holder 32 onto any one of the pre-treatment tank 61, the plating tank 62, the water washing tank 71, and the post-treatment tank 74. In this state, the arm vertical movement drive unit 34 moves the holder 32 upward and downward to take the wafer W held by the holder 32 in and out from any one of the pre-treatment tank 61, the plating tank 62, the water washing tank 71, and the post-treatment tank 74. Thus, only through the operation of moving the holder 32 vertically by the arm vertical movement drive unit 34, it is possible to realize the operations of immersing, inserting and taking out the surface B to be treated of the wafer W held by the holder 32 with respect to the pre-treatment tank 61, the plating tank 62, the water washing tank 71, and the post-treatment tank 74. As a result, the operation of conveying the wafer 4 and the structure necessary for conveying the wafer W can be simplified. Furthermore, since only the surface B to be treated of the wafer 7 which is exposed through the opening 42 of the lower part 37 of the holder 32 is plated, it is possible to simplify the plating process for the wafer 71 which is performed by the plurality of treatment units 14.
In particular, when the arm vertical movement drive unit 34 moves the holder 32 downward to immerse the lower end of the housing recess 41 of the lower part 37 of the holder 32, for example, in the plating solution M in the plating tank 62, as illustrated in
Furthermore, in the plating unit 14b, the arm vertical movement drive unit 34 moves the holder 32 downward to immerse the lower end of the housing recess 41 of the holder 32 in the plating solution M of the plating tank 62. Then, as illustrated in
Furthermore, in the state where the wafer W is placed on the bottom surface of the housing recess 41 of the lower part 37 of the holder 32 and then the insertion projection 51 of the upper part 38 is inserted into the housing recess 41 of the lower part 37 to integrate the lower part 37 with the upper part 38, the wafer rotation drive unit 35 rotates the holder 32 in the circumferential direction to rotate the wafer W held by the holder 32. Thus, through the same operation of rotating the holder 32 by the wafer rotation drive unit 35, it is possible to drain the plating solution M adhering to the surface B to be treated during the pre-treatment process, drain the plating solution M adhering to the surface B to be treated during the plating process, drain the pure water adhering to the plating layer of the wafer W during the water washing process, dry the post-treatment solution adhering to the plating layer of the wafer W during the post-treatment process, drain the pure water adhering to the protective film of the wafer during the water washing process, and dry the wafer W during the drying process.
Furthermore, since the wafer W is placed on the bottom. surface of the housing recess 41 of the lower part 37 of the holder 32 after the wafer reversing mechanism 22 reverses the surfaces of the wafer W upside down, the wafer W can be housed on the bottom surface of the housing recess 41 of the lower part 37 in a state where the surface B to be treated of the wafer, which had. been conveyed onto the stage 12 with the surface B to be treated facing upward, has been reversed by the wafer reversing mechanism 22 so as to face downward. This causes the surface B to be treated of the wafer W to be exposed through the opening 42 of the lower part 37, and when the lower end of the housing recess 41 of the lower part 37 of the holder 32 is inserted into the pre-treatment tank 61, the plating tank 62, or the post-treatment tank 74, the surface B to be treated of the wafer W can be immersed in the plating solution M filling the pre-treatment tank 61 and the plating tank 62 or the post-treatment solution filling the post-treatment tank 74. As a result, only through the operation of moving the holder 32 upward and downward by the arm vertical movement drive unit 34, it is possible to easily perform the processes of pre-treatment, plating, and post-treatment for the surface B to be treated of the wafer W held by the holder 32.
Furthermore, the wafer W housed in the shuttle with the surface B to be treated facing upward is taken out from the shuttle while the surface B to be treated remains facing upward, and then the PLAD system 9 conveys the wafer W to the stage 12 in a state where the lower surface of the wafer W is supported thereby. Then, after the wafer reversing mechanism 22 reverses the front and back surfaces of the wafer W which has been conveyed to the stage 12 so as to make the surface B to be treated face downward, the wafer W is placed on the housing recess 41 of the lower part 37 of the holder 32. Thus, the operations during which the wafer W is taken out from the shuttle and conveyed to the stage 12 are performed by the PLAD system 9 in such a way that a portion other than the surface B to be treated, namely, the lower surface of the wafer W is held thereby, and accordingly, it is possible to convey the wafer W without allowing the surface B to be treated to be touched. Furthermore, the operations during which the wafer W is conveyed from the stage 12 and placed Jr on housing recess 41 of the holder 32 are performed in such a way that the wafer W is housed in the housing recess 41 of the lower part 37 after the back surface of the wafer W is sucked by the suction pad 24 and turned over by the wafer reversing mechanism 22. Thus, only through the operations of making the surface other than the surface B to be treated of the wafer W, namely, the lower surface sucked. t the suction pad 24 and then reversed, the wafer W is housed in the housing recess 41. Accordingly, the wafer W can be inserted into the housing recess 41 without allowing the surface B to be treated to be touched.
Similarly, the operations during which the wafer W is taken. out from. the housing recess 41 of the lower part 37 and conveyed onto the stage 12 are performed in such a way that the wafer W is conveyed. to the stage 12 after the surface other than the surface B to be treated, namely, the back surface is sucked by the suction pad 24 and turned over, and accordingly, it is possible to convey the wafer W without allowing the surface B to be treated to be touched by the suction pad 24. Furthermore, the operations during which the wafer W is conveyed from the stage 12 and placed onto the shuttle are performed by the PLAD system 9 in such a way that the lower surface of the wafer W is held thereby, and accordingly, it is possible to convey the wafer W without allowing the surface B to be treated to be touched. Thus, in each of the operations during which the wafer W is conveyed from the shuttle and placed on the bottom surface of the housing recess 41 of the lower part 37 of the holder 32, and the operations during which wafer W is taken out from the housing recess 41 of the lower part 37 and housed in the shuttle, it is possible to reliably prevent the surface B to be treated from being damaged during convey of the wafer W.
In particular, after the process of plating the surface B to be treated, the arm rotation drive unit 33 rotates the conveying arm 31 in an arc to convey the holder 32 to the wafer housing unit 14f, and then the arm vertical movement drive unit 34 moves the conveying arm 31 downward to place the lower part 37 of the holder 32 on the wafer housing unit 14f. In this state, the drive mechanism moves the engagement piece member 79 of the chuck mechanism 78 in the direction toward the central axis, as illustrated in
Furthermore, since the wafer W has a disc-shape having the outside diameter of 12.5 mm, is possible to use this wafer W in a so-called minimal fab system. Similarly, since the plating machine 1 is provided for plating the wafer W, it is possible to use the plating machine 1 as a plating machine in a so-called minimal fab system.
The technical problems of plating machines are mainly, (1) making the film thickness of the plating layer formed by plating uniform and shortening the time required for plating, and (2) improving productivity. Among these technical problems, in order to solve the technical problem (1), it is necessary to accelerate the updating of the plating solution on a surface of an object to be treated such as a wafer or a substrate. As specific methods therefor, for example, (1A) stirring the plating solution (see, for example, Non-Patent Literature: Kadota et al., “High-speed plating technique for three-dimensionally mounted through electrode”, Journal of Institute of Electronics Packaging, Vol. 13, No. 3, pages 213 to 219 (2010)) or (1B) moving the object to be treated are possible approaches.
The possible methods for stirring the plating solution described in the approach (1A) above include, for example, (a1) a method of stirring the plating solution using a stirrer, (a2) a method of stirring the plating solution horizontally using a so-called squeegee (see, for example, Patent Literature: JP-A-2005-054206), (a3) a method of spraying the plating solution onto the object using a jet nozzle (see, for example, Patent Literatures: JP-A-2007-277676 and JP-A-2006-265709), and (a4) a method of circulating the plating solution as a high-speed flow (see, for example, Patent Literature: JP-A-2005-054206).
The possible methods for moving the object to be treated described in the approach (1B) above includes, for example, (b1) a method of linearly reciprocating the object to be plated in the plating solution (see, for example, Patent Literature 1) and (b2) a method of horizontally or vertically rotating the object to be treated in the plating solution (see, for example, Patent Literatures: JP-A-2004-300462 and JP-A-2010-265532). In this connection, it should be noted that, depending on the direction of rotating the object to be treated in the plating solution, there is a possibility that the rotational resistance received from the plating solution increases, which causes decrease of the stirring force.
Furthermore, as the solutions for the technical problem (2) above, methods of plating an object to be treated by continuous processes are possible approaches. These methods include, for example, (2A) a vertically and continuously conveying method in which an upper end of a substrate that is vertically standing is held and conveyed (see, for example, Patent Literature 1), or (2B) a horizontally conveying method using a robot or the like (see, for example, Patent Literature: JP-A-2003-171791).
Among these methods, the combination of (2A) the vertically and continuously conveying method with (a3) the method of spraying the plating solution onto the object to be treated using a nozzle, or the combination of (2A) with (b1) the method of linearly reciprocating the object to be treated may solve each of the technical problems (1) and (2). However, these combinations may reduce the stirring force of the plating solution, and thus there is a possibility that the plating solution cannot be appropriately stirred.
The combination of (2B) the horizontally conveying method with (a2) the method of stirring the plating solution using the squeegee, the combination of (2B) with (a3) the method of spraying the plating solution onto the object to be treated. using a let nozzle, the combination of (2B) with (a4) the method of circulating the plating solution at high speed, or the combination of (2B) with (b2) the method of rotating the object to be treated in the plating solution may be possible. However, these combinations are based on the horizontally conveying method, and accordingly, it is necessary to fill and discharge the plating solution every time the object to be treated is plated. Furthermore, since the stirring force of the plating solution is small, there is a possibility that the plating solution cannot be appropriately stirred. Still further, the structure according to each of the combinations above makes the structure for sealing the rotary shaft for rotating the object to be treated complex, and also makes the operations of carrying in and out the object to be treated difficult.
In view of these matters, in the plating machine 1 according to the embodiment described above, in accordance with the rotation of the holder 32 by the wafer rotation drive unit 35, the wafer W is rotated in the circumferential direction in the plating solution of the plating tank 62 at high speed, and thus a high-speed flow of the plating solution is generated. Furthermore, the plurality of treatment units 14, namely, the pre-treatment unit 14a, the plating unit 14b, the water washing unit 14c, the post-treatment unit 14d, the drying unit 14e, and the wafer housing unit 14f are arranged side by side on the same circumference around the center position of the stage 12, and the wafer W is conveyed to the plurality of treatment units 14 by the arc movement of the single conveying arm 31, thereby realizing the processes by the plurality of treatment units 14 as continuous processes.
Furthermore, in the plating machine 1 according to the embodiment described above, after the wafer reversing mechanism 22 reverses the wafer W, the wafer W is held by the holder 32 in this state and conveyed together with the holder 32 to the plurality of treatment units 14. The wafer W is rotated in accordance with the rotation of the holder 32, thereby making it possible to rotate the wafer W at high speed during processes in each of the treatment units 14. In addition, special control corresponding to each process is not required to rotate the wafer W at high speed, and as a result, it is possible to realize the processes by the plurality of treatment units 14 as continuous processes.
In the embodiment described above, on the rotation trajectory of the holder 32, the pre-treatment unit 14a, the plating unit 14b, the water washing unit 14c, the post-treatment unit 14d, the drying unit 14e, and the wafer housing unit 14f are arranged at the predetermined intervals. However, the present invention is not limited thereto, and various types of processing units used for plating can be similarly arranged on the rotation trajectory of the holder 32 at the predetermined intervals.
Furthermore, even wafers other than the wafer W having a single crystal silicon structure or large-diameter wafers that is larger than the minimal wafer of the half-inch size can be adapted and used.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-072823 | Apr 2021 | JP | national |
