The disclosure of Japanese Patent Application No. 2009-273240 filed on Dec. 1, 2009 including the specification, drawings and abstract is incorporated herein by reference in its entirety.
The present invention relates to a technique effectively applied to metal sputtering deposition technology in a manufacturing method of a semiconductor integrated circuit device (or semiconductor device).
Japanese Unexamined Patent Publication Number No. Hei 11(1999)-269644 (Patent Document 1) discloses a technique of sputter etching for removing a natural oxide film or the like in a different chamber before deposition of a metal film or the like by sputtering. In the technique, a film or the like of metal with a small stress, such as aluminum, is previously formed over an inner wall of the different chamber to suppress falling of particles of silicon oxide-based material.
Japanese Unexamined Patent Publication Number No. 2000-331989 (Patent Document 2) discloses a technique in which an inner wall of a chamber in a dry etching device for a silicon oxide film is uniformly covered with a silicon oxide film to thereby suppress falling of silicon oxide-based particles unevenly deposited.
Japanese Unexamined Patent Publication Number No. Hei 4(1992)-286112 (Patent Document 3) discloses a technique in which a TiN film having a stress opposite to that of a TiN film previously deposited over a wafer is deposited at an inner surface of a shield of a chamber in a sputter deposition device for TiN to thereby suppress falling of particles or the like.
Japanese Unexamined Patent Publication Number No. 2007-311461 (Patent Document 4) discloses a technique for continuously depositing a Ti film and a TiN film by sputtering in the same chamber. In the technique, before depositing the above Ti film, another Ti film is deposited over a shutter by sputtering so as to reduce influences on the Ti film due to the residual nitrogen.
Japanese Unexamined Patent Publication Number No. Hei 11(1999)-269644
Japanese Unexamined Patent Publication Number No. Hei 2000-331989
Japanese Unexamined Patent Publication Number No. Hei 4(1992)-286112
Japanese Unexamined Patent Publication Number No. Hei 2007-311461
In a copper damascene wiring process, for example, a tantalum-based laminated film comprised of a tantalum nitride film as a lower layer and a tantalum film as an upper layer is used as a barrier metal film. Formation of the tantalum-based laminated film is continuously performed in the same sputtering deposition chamber in a normal mass production process.
The inventors of the present invention have studied about such a continuous deposition process, and found out the following problems. That is, when the continuous deposition process is discontinuously repeated on a number of wafers, the tantalum film and the tantalum nitride film which are relatively thin are alternately deposited over an inner surface of a shield in a sputtering deposition chamber (substantially inner surface of the chamber), which results in thickness of a deposited film on the order of one thousand nanometers to several thousand nanometers at the time of the wafer process. Thus, when the thickness of the deposited film in the wet process (total thickness of the deposited film in the wet process) is large, the deposited film may be peeled off due to an internal stress therein, which causes foreign material or particles. The foreign material or particles may cause failures of the wiring. The tantalum film and the tantalum nitride film both have the same direction of stress (compression stress), and thus may be peeled off due to the increased internal stress of the laminated film.
The invention of the present application is to solve the above problems.
Accordingly, it is an object of the invention to provide a manufacturing process of a semiconductor integrated circuit device with high reliability.
The above, other objects, and novel features of the invention will become apparent from the description of the present specification with reference to the accompanying drawings.
The outline of representative aspects of the invention disclosed in the present application will be briefly described below.
That is, the invention of the present application is directed to a manufacturing method of a semiconductor integrated circuit device which includes the step of depositing a tantalum film for preventing foreign material at predetermined intervals in repeatedly depositing a tantalum nitride film and a tantalum film over a number of wafers in a sputtering deposition chamber. The tantalum film for preventing foreign material is much thicker than the tantalum film formed over the wafer at one time.
The effects obtained by the representative aspects of the invention disclosed in the present application will be briefly described below.
That is, in a case where the tantalum nitride film and the tantalum film are repeatedly deposited over each of a number of wafers in the sputtering deposition chamber, the manufacturing method of the semiconductor integrated circuit device includes the step of depositing over the substantial inner wall of the chamber the tantalum film for preventing foreign material at the predetermined intervals. The tantalum film for preventing foreign material has a thickness much larger than that of the tantalum film formed over the wafer at one time. As a result, the surface of the deposited film at the time of the wafer process is coated with the thick film having a relatively small Young's modulus, which can reduce foreign material and particles.
First, the outline of representative preferred embodiments of the invention disclosed in the present application will be described below.
1. A manufacturing method of a semiconductor integrated circuit device includes the following steps of: (a) introducing a wafer to be processed, into a chamber; (b) depositing a tantalum nitride film having a first thickness over the wafer to be processed in the chamber by sputtering; (c) after the step (b), depositing a first tantalum film having a second thickness over the wafer to be processed in the chamber by the sputtering; (d) discharging the wafer to be processed to an outside of the chamber; (e) sequentially applying a lower-level process cycle including the steps (a) to (d) to a plurality of wafers to be processed that are different from the wafer belonging to a previous lower-level process cycle; (f) after the step (e), depositing a second tantalum film having a third thickness much larger than the second thickness, over an inner wall of the chamber by sputtering in the chamber; and (g) repeating a higher-level process cycle including the steps (a) to (f).
2. In the manufacturing method of the semiconductor integrated circuit device according to Item 1, the step (f) is performed before the total thickness of the deposited film in the last wafer process exceeds 1000 nm.
3. In the manufacturing method of the semiconductor integrated circuit device according to Item 1 or 2, the step (f) is performed after the total thickness of the deposited film in the last wafer process exceeds 300 nm.
4. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 1 to 3, the third thickness is not less than 100 nm, and less than 500 nm.
5. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 1 to 4, the sum of the first thickness and the second thickness is not less than 5 nm, and less than 30 nm.
6. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 1 to 5, the step (f) is performed after the total thickness of the deposited film in the last wafer process exceeds 500 nm.
7. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 1 to 6, the third thickness is not less than 150 nm, and less than 350 nm.
8. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 1 to 7, the step (f) is performed before the total thickness of the deposited film in the last wafer process exceeds 800 nm.
9. A manufacturing method of a semiconductor integrated circuit device includes the following steps of: (a) introducing a wafer to be processed, into a first chamber; (b) depositing a tantalum nitride film having a first thickness over the wafer to be processed in the first chamber; (c) after the step (b), taking the wafer to be processed out of the first chamber to introduce the wafer into a second chamber; (d) depositing a ruthenium film having a second thickness over the wafer to be processed, in the second chamber by sputtering; (e) discharging the wafer to be processed to an outside of the second chamber; (f) sequentially applying a lower-level process cycle including the steps (a) to (e) to a plurality of wafers to be processed that are different from the wafer belonging to a previous lower-level process cycle; (g) after the step (f), depositing a tantalum film over an inner wall of the first chamber by sputtering in the first chamber, the tantalum film having a third thickness much larger than the first thickness; and (h) repeating a higher-level process cycle including the steps (a) to (g).
10. In the manufacturing method of the semiconductor integrated circuit device according to Item 9, the step (g) is performed before a total thickness of the deposited film in the last wafer process exceeds 1000 nm.
11. In the manufacturing method of the semiconductor integrated circuit device according to Item 9 or 10, the step (g) is performed after the total thickness of the deposited film in the last wafer process exceeds 300 nm.
12. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 9 to 11, the third thickness is not less than 100 nm and less than 500 nm.
13. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 9 to 12, the second thickness is not less than 5 nm and less than 20 nm.
14. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 9 to 13, the step (g) is performed after the total thickness of the deposited film in the last wafer process exceeds 500 nm.
15. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 9 to 14, the third thickness is not less than 150 nm and less than 350 nm.
16. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 9 to 15, the step (g) is performed before the total thickness of the deposited film in the last wafer process exceeds 800 nm.
17. A manufacturing method of a semiconductor integrated circuit device includes the following steps of: (a) introducing a wafer to be processed, into a chamber; (b) depositing a first barrier metal film having a first thickness over the wafer to be processed in the chamber by sputtering, the first barrier metal film containing a first metal nitride as a principal component; (c) after the step (b), depositing a second barrier metal film having a second thickness over the wafer to be processed in the chamber by sputtering, the second barrier metal film containing the first metal as a principal component; (d) discharging the wafer to be processed to an outside of the chamber; (e) sequentially applying a lower-level process cycle including the steps (a) to (d) to a plurality of wafers to be processed that are different from the wafer belonging to a previous lower-level process cycle; (f) after the step (e), depositing an inner wall coating film over an inner wall of the chamber by sputtering in the chamber, the inner wall coating film having a third thickness much larger than the second thickness, and containing a first metal as a principal component; and (g) repeating a higher-level process cycle including the steps (a) to (f). Each of the first barrier metal film and the inner wall coating film has a compression stress.
18. In the manufacturing method of the semiconductor integrated circuit device according to Item 17, the step (f) is performed before the total thickness of the deposited film in the last wafer process exceeds 1000 nm.
19. In the manufacturing method of the semiconductor integrated circuit device according to Item 17 or 18, the step (f) is performed after the total thickness of the deposited film in the last wafer process exceeds 300 nm.
20. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 17 to 19, the third thickness is not less than 100 nm and less than 500 nm.
21. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 17 to 20, the sum of the first thickness and the second thickness is not less than 5 nm and less than 30 nm.
22. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 17 to 21, the step (f) is performed after the total thickness of the deposited film in the last wafer process exceeds 500 nm.
23. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 17 to 22, the third thickness is not less than 150 nm and less than 350 nm.
24. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 17 to 23, the step (f) is performed before the total thickness of the deposited film in the last wafer process exceeds 800 nm.
25. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 1 to 8, a Young's modulus of the second tantalum film is lower than that of the tantalum nitride film.
26. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 9 to 16, a Young's modulus of the tantalum film is lower than that of the tantalum nitride film.
27. In the manufacturing method of the semiconductor integrated circuit device according to any one of Items 17 to 24, a Young's modulus of the inner wall coating film is lower than that of the first barrier metal film.
28. In the manufacturing method of the semiconductor integrated circuit device according to Item 17, the second barrier metal film has a compression stress, like the first barrier metal film and the inner wall coating film.
29. A manufacturing method of a semiconductor integrated circuit device includes the following steps of: (a) introducing a wafer to be processed into a chamber; (b) depositing a first barrier metal film having a first thickness over the wafer to be processed by sputtering in the chamber; (c) after the step (b), depositing a second barrier metal film having a second thickness over the wafer to be processed by sputtering in the chamber; (d) discharging the wafer to be processed to an outside of the chamber; (e) sequentially applying a lower-level process cycle including the steps (a) to (d) to a plurality of wafers to be processed that are different from the wafer belonging to a previous lower-level process cycle; (f) after the step (e), depositing an inner wall coating film over an inner wall of the chamber by sputtering in the chamber, the inner wall coating film having a third thickness larger than the total thickness of the first film and the second film; and (g) repeating a higher-level process cycle including the steps (a) to (f). Each of the first barrier metal film and the second barrier metal film has a compression stress, and the inner wall coating film is the same as one of the first barrier metal film and the second barrier metal film.
30. In the manufacturing method of the semiconductor integrated circuit device according to Item 29, the inner wall coating film is the same as one having a lower Young's modulus of the first barrier metal film and the second barrier metal film.
1. The description of the following preferred embodiments in the present application may be divided into sections, or based on the respective embodiments, for convenience if necessary, but these embodiments are not independent from each other except when specified otherwise. One of the embodiments corresponds to each part of a single example, or is a part of the details of the other, a modified example of a part or all of the other, or the like. The repeated description of the same part will be omitted in principal. Each component of the embodiments is not essential unless otherwise specified, except when the number of the components is limited in principle, or unless the context clearly indicates otherwise.
Further, the term “semiconductor device” or “semiconductor integrated circuit device” as used in the present application mainly means a single device of various kinds of transistors (active elements), or a device including these various transistors, such as a resistor or a capacitor, integrated on a semiconductor chip or the like (for example, a monocrystalline silicon substrate). Various types of representative transistors can include, for example, a metal insulator semiconductor field effect transistor (MISFET), typified by a metal oxide semiconductor field effect transistor (MOSFET). At this time, the typical integrated circuit structure can include, for example, a complementary metal insulator semiconductor (CMIS) type integrated circuit, typified by a complementary metal oxide semiconductor (CMOS) type integrated circuit with a combination of an N-channel type MISFET and a P-channel type MISFET. The above-mentioned term “Metal” is not limited to single metal, but also contains a conductive material (for example, polysilicon and the like).
Normally, the wafer process of present semiconductor integrated circuit devices, that is, a large scale integration (LSI) can be broadly classified into a front end of line (FEOL) process and a back end of line (BEOL) process. The FEOL process includes a step from delivery of a silicon wafer as a raw material to a premetal process (involving formation of an interlayer insulating film between a low end of a M1 wiring layer and a gate electrode structure, formation of a contact hole, formation of a tungsten plug, embedding, and the like). The BEOL process includes a step from the formation of the Ml wiring layer to the formation of a pad opening in a final passivation film on an aluminum pad electrode (including a wafer level package process). Among the FEOL process, a gate electrode patterning step, a contact hole formation step, and the like are microfabrication steps, specifically, requiring a fine process. On the other hand, in the BEOL process, a via and trench formation step requires a fine process in a local wiring as a relatively lower layer (for example, fine embedded wirings M1 to M3 in an embedded wiring structure having four layers, or fine embedded wirings M1 to M5 in an embedded wiring structure having about ten layers). The term “MN (normally, N=about anyone of 1 to 15” means an N-th layered wiring from the bottom. The M1 indicates the first layer wiring, and the M3 indicates the third layer wiring.
2. Likewise, in the description of the embodiments or the like, the phrase “X made of A” about material, component, or the like does not exclude a member containing an element other than A as a principal component unless otherwise specified, or unless the context clearly indicates otherwise. For example, as to a component, the above phrase means “X containing A as a principal component” or the like.
It is apparent that for example, the term “a silicon member” or the like is not limited to pure silicon, and may include multicomponent alloy containing SiGe alloy or other silicon materials as a principal component, and a member containing other additives or the like. The same goes for a “copper wiring” (also including a copper-based wiring or the like), a “tantalum film”, a “tantalum nitride film”, or a “ruthenium film”, or the like.
Likewise, it is apparent that the term “silicon oxide film” or “silicon oxide-based insulating film” or the like includes not only a relatively pure undoped silicon dioxide, but also a thermally-oxidized film made of, for example, fluorosilicate glass (FSG), TEOS-based silicon oxide, silicon oxicarbide (SiOC), carbon-doped silicon oxide, organosilicate glass (OSG), phosphorus silicate glass (PSG), borophosphosilicate glass (BPSG), or the like, a CVD oxide film, a coating-type silicon oxide film, such as spin on glass (SOG), or a nano-clustering silica (NCS), a silica-based Low-k insulating film (porous insulating film), a composite film with another silicon insulating film containing the above component as a principal component.
Silicon insulating films generally used in the field of semiconductor devices are a silicon nitride-based insulating film, in addition to the silicon oxide-based insulating film. Suitable materials of such a kind include SiN, SiCN, SiNH, SiCNH, and the like. The term “silicon nitride” as used herein include both SiN and SiNH, unless specified otherwise. Likewise, the term “SiCN” as used herein includes both SiCN and SiCNH, unless specified otherwise.
SiC has the similar properties to those of SiN, and SiON should be often classified into a silicon oxide-based insulating film.
3. Likewise, it is apparent that preferred examples of graphics, positions, properties, and the like will be described below in the embodiments, but the invention is not strictly limited thereto unless otherwise specified, or unless the context clearly indicates otherwise.
4. Further, when referring to a specific value or quantity, the invention may have a value exceeding the specific value, or may have a value less than the specific value, unless otherwise specified, except when limited to the specific value in theory, or unless the context clearly indicates otherwise.
5. The term “wafer” generally indicates a monocrystalline silicon wafer over which a semiconductor integrated circuit device (note that the same goes for a semiconductor device, and an electronic device) is formed, but may include a composite wafer of an insulating substrate, such as an epitaxial wafer, an SOI wafer, or a LCD glass substrate, and a semiconductor layer, or the like.
The preferred embodiments will be further described below in detail. In each drawing, the same or similar part is designated by the same or similar reference character or numeral, and a description thereof will not be repeated in principal.
In the accompanying drawings, hatching or the like may be omitted even in the cross-sectional view when the drawing possibly becomes complicated or when apart shown in the drawing is apparently distinguished from a cavity. In a related matter, when the presence of a hole closed in a planar manner is clearly understood from the description thereof, a background outline of the hole may be often omitted. Further, hatching may be provided even in any drawing other than the cross-sectional view in order to clearly show that a part of interest in the drawing is not the cavity.
1. Explanation of Device Cross-Sectional Structure at Time of Completion of Pad Opening at Aluminum-based Pad of Semiconductor Integrated Circuit Device of Interest in Manufacturing Method Thereof According to First Embodiment of Present Application (mainly see
As shown in
A first wiring layer M1 on the film 5 is comprised of an insulating barrier film 14 made of a SiCN film (for example, of about 50 nm in thickness) as a lower layer, a plasma silicon oxide film 15 which is a main interlayer insulating film (for example, of about 150 nm in thickness), and a copper wiring 13 or the like embedded in wiring trenches formed therein.
Second to sixth wiring layers M2, M3, M4, M5, and M6 on the layer M1 have substantially the same structure to each other. Each layer is comprised of a composite insulating barrier film (liner film) 24, 34, 44, 54, or 64 including a SiCO film (for example, of about 30 nm in thickness) as a lower layer/SiCN film (for example, of about 30 nm), and a main interlayer insulating film 25, 35, 45, 55, or 65 occupying most of the upper layer. Each of the main interlayer insulating films 25, 35, 45, 55, and 65 is comprised of a carbon doped silicon oxide film as a lower layer, that is, a SiOC film (for example, of about 350 nm in thickness), and a plasma TEOS silicon oxide film (for example, of about 80 nm in thickness) as a cap film. Copper embedded wirings 23, 33, 43, 53, and 63 including a copper plug and a copper wiring are formed through the interlayer insulating film.
A seventh wiring layer M7 and an eighth wiring layer M8 formed over the layer M6 have substantially the same structure to each other. Each layer is comprised of an insulating barrier film 74 or 84 formed of a SiCN film (for example, of about 70 nm in thickness) as a lower layer, and a main interlayer insulating film 75 or 85 as an upper layer. The main interlayer insulating film 75 or 85 is comprised of a plasma TEOS silicon oxide film (for example, of about 250 nm in thickness), a FSG film (for example, of about 300 nm in thickness), and a USG film serving as a cap film (for example, of about 200 nm in thickness) from the lower layer side. Copper embedded wirings 73 and 83 including a copper plug and a copper wiring are formed through the interlayer insulating films.
A ninth wiring layer M9 and a tenth wiring layer M10 formed over the layer M8 have substantially the same structure to each other. Each layer is divided into an interlayer as a lower layer and an intralayer as an upper layer. The interlayer insulating film is comprised of an insulating barrier film 94b or 104b made of a SiCN film (for example, of about 70 nm in thickness) as a lower layer, and a main interlayer insulating film as an upper layer. The main interlayer insulating film is comprised of a FSG film 95b or 105b (for example, of about 800 nm in thickness) as a lower layer, and a USG film 96b or 106b (for example, of about 100 nm in thickness) serving as a cap film positioned as an upper layer. The intralayer insulating film is comprised of an insulating barrier film 94a or 104a made of a SiCN film (for example, of about 50 nm in thickness) as a lower layer, and a main interlayer insulating film as an upper layer. The main interlayer insulating film is comprised of a FSG film 95a or 105a (for example, of about 1200 nm in thickness) as a lower layer, and a USG film 96a or 106a (for example, of about 100 nm in thickness) serving as a cap film positioned as an upper layer. Copper embedded wirings 93 and 103 including a copper plug and a copper wiring are formed through the interlayer insulating film and the intralayer insulating film.
An uppermost wiring layer (pad layer) AP formed on the layer M10 is comprised of an insulating barrier film made of a SiCN film 114 (for example, of about 10 nm in thickness) as a lower layer, a main interlayer insulating film made of an intermediate USG film 117 (for example, of about 900 nm in thickness), and a final passivation film made of an outermost plasma SiN119 (for example, of about 600 nm in thickness). Tangusten plugs 113 are provided through the interlayer insulating films, and an aluminum bonding pad 118 (for example, of about 1000 nm in thickness) is provided over the USG film 117. The aluminum bonding pad 118 and the tungsten plug 113 have a titanium bonding layer 151 (for example, of about 100 nm in thickness) as the lower layer, and a titanium nitride barrier metal layer 152 (for example, of about 30 nm in thickness) as the upper layer if necessary. A titanium nitride layer 153 (for example, of about 70 nm in thickness) is formed over the bonding pad 118, and an opening is formed in the layer 153 and the plasma SiN 119 to form a bonding pad opening 163.
Instead of the aluminum bonding pad 118, a copper-based bonding pad may be used.
2. Explanation of Wiring Embedding Process in Manufacturing Method of Semiconductor Integrated Circuit Device According to One Embodiment of Present Application (mainly see
The following section will describe a wiring embedding process by taking the third wiring layer M3 (copper) shown in
First, the insulating barrier film 34 and the main interlayer insulating film 35 are deposited by chemical vapor deposition (CVD) or the like. Then, as shown in
Then, as shown in
Subsequently, for example, a tantalum film 33b (Ta film) having a thickness of about 10 nm (second thickness) is formed over the tantalum nitride film 33a by sputtering using the tantalum target. Process conditions are, for example, as follows: wafer stage temperature, ordinary temperature (room temperature); DC power applied to the upper electrode, about 15 kilowatts; high frequency power applied to the lower electrode (for example, 13.56 MHz), about 200 watts; Argon flow rate, about 5 sccm; process pressure, about 0.06 Pa; and process time, about 15 seconds. Instead of the tantalum film 33b, a ruthenium film having substantially the same thickness may be deposited by sputtering or the like (or can be performed by a CVD or the like). The ruthenium film is superior in crystallizing consistency and adhesion to copper. The first barrier metal film is not limited to the tantalum nitride film as long as it can contain as a principal component a first metal nitride having a barrier property against diffusion of copper (which is desirably a film having better consistency with the interlayer insulating film). The second barrier metal film is not limited to the tantalum film or ruthenium film, and may be one containing as a principal component the first metal or other metal element having a barrier property against diffusion of copper (which is desirably a film having better consistency with copper).
Then, as shown in
Then, as shown in
Then, as shown in
3. Explanation of Manufacturing Device or the like Used in Wiring Embedding Process in Manufacturing Method of Semiconductor Integrated Circuit Device According to One Embodiment of Present Application (mainly see
As the process route, in a Ta/TaN barrier metal process of Section 2 (
First, as shown in
The wafer 1 to be processed is carried into a vacuum delivery chamber 208 through a pre-cleaning chamber 204 with a down-flow mechanism 205 and a load lock chamber 207 by a delivery robot 206. The wafer 1 to be processed is carried from the vacuum delivery chamber 208 into the degas chamber 209, and subjected to a vacuum baking process (degas process). Subsequently, the wafer 1 to be processed is moved to a pretreatment chamber 211 via the vacuum delivery chamber 208, and then subjected to the pretreatment. The term “pretreatment” as used herein means removal process of impurities, such as CuO, remaining on the exposed surface of the Cu film 23c as a lower layer, by physical sputter etching using Ar ions, or by a reduction reaction with H2 radicals. Then, the wafer 1 to be processed is transferred to a Ta and TaN deposition chamber 212 via the vacuum delivery chamber 208, where sputtering deposition of a barrier metal film (including sputter etching and re-sputter deposition of the tantalum film in the case of Section 5) is performed. Then, the wafer 1 to be processed is transferred to a copper seed deposition chamber 214 via the vacuum delivery chamber 208, so that a copper seed film 33s is deposited by sputtering. In the Ru/TaN barrier metal process, the wafer 1 to be processed is previously transferred to a ruthenum deposition chamber 232 via the vacuum delivery chamber 208, so that a ruthenium barrier film is deposited by sputtering or the like.
After forming the copper seed film 33s, the wafer 1 to be processed is returned to the hoop 203 via the vacuum delivery chamber 208, the load lock chamber 207, and the pre-cleaning chamber 204. Thereafter, the wafer 1 is transferred to a plating device, so that the electroplating of copper is performed as shown in
Then, the structure of the Ta and TaN deposition chamber 212 (or TaN deposition chamber) shown in
Next, the following will describe introduction and discharge of the wafer 1 or shutter disk 216 into and from the chamber 212. As shown in
4. Explanation of Procedure in Applying Wiring Embedding Process to Mass production in Manufacturing Method of Semiconductor Integrated Circuit Device According to One Embodiment of Present Application (mainly see
This section will describe in detail a barrier metal film deposition process described in Section 2 with reference to
The process (corresponding to
Then, a tantalum nitride film deposition step S302 (see
In the process described in Section 5, a hole bottom etching step S324 (see
The processes from the wafer introduction step S301 to the wafer discharge step S304 form the lower-level process recycle 311 including the barrier metal deposition process and the like. In the mass production, the lower-level process recycle 311 is repeated. As shown in
The above points will be described below using
The thickness of the thick metal film 7, that is, the thick metal film thickness TP is, for example, about 300 nm. On the other hand, the thickness of the in-process deposited film 6 directly before deposition of the thick metal film 7, that is, the total thickness TQ of the deposited film in the wafer process is, for example, about 750 nm.
That is, the predetermined timing is, for example, the time when the total thickness TQ of the deposited film in the wafer process is about 300 nm. The deposition step S305 of the thick tantalum film over the inner surface of the shield 218 is performed, for example, in the following way. The shutter disk 216 (wafer-like metal plate) with the wafer 1 not positioned on the stage 215 as illustrated in
Now, referring to
On the other hand, the total thickness TQ of the deposited film in the wafer process directly before the execution of the thick tantalum film deposition step S305 over the seed can be defined based on
Normally, the sum of the thicknesses of the tantalum nitride film and the tantalum film deposited over the wafer 1 at one time is not less than 5 nm and less than 30 nm (the sum of the thicknesses of the tantalum nitride film and the ruthenium film is not less than 5 nm and less than 20 nm). The thickness of 750 nm corresponds to about 25 to 150 pieces of wafers to be processed (that is, one to six lots when 25 pieces are brought into one lot).
5. Explanation of Wiring Embedding Process in Manufacturing Method of Semiconductor Integrated Circuit Device According to Another Embodiment of Present Application (mainly see
The wiring embedding process to be described in this section is basically the same as that described in Section 2, but is different in that the respective steps shown in
First, the insulating barrier film 34 and the main interlayer insulating film 35 are deposited by the CVD or the like in the same way as that described in Section 2. Then, as shown in
Then, as shown in
Subsequently, for example, the tantalum film 33b (Ta film) having a thickness of about 10 nm is formed over the tantalum nitride film 33a by sputtering using the tantalum target. Process conditions are, for example, as follows: wafer stage temperature, ordinary temperature (room temperature); DC power applied to an upper electrode, about 20 kilowatts; high frequency power applied to a lower electrode (for example, 13.56 MHz), about 200 watts; Argon flow rate, about 5 sccm; process pressure, about 0.06 Pa; and process time, about 15 seconds.
Then, as shown in
Then, as shown in
Then, as shown in
Then, as shown in
Then, as shown in
6. Summary
Although the invention made by the inventors has been specifically described based on the preferred embodiments, the invention is not limited thereto. It will be apparent to those skilled in the art that various modifications can be made to the presently disclosed embodiments without departing from the scope of the invention.
For example, although this embodiment has specifically described the example of the copper-based damascene wiring (single damascene and dual damascene wirings), the invention is not limited thereto. It is apparent that the invention can also be applied to other damascene wirings other than the copper-based one, such as a silver-based damascene wiring.
Although the above-mentioned embodiments have specifically described the examples of deposition of the barrier metal film of the damascene wiring (embedded wiring), the invention is not limited thereto. It is apparent that the invention can also be widely applied to prevent generation of foreign material in the sputtering deposition.
Further, although the thick tantalum film has been specifically described as one example of use of the inner wall coating film for preventing foreign material, the invention is not limited thereto. It is needless to say that the invention can use any other film that has the stress in the same direction as that of the in-process deposited film inevitably deposited during the deposition process over the wafer, which has a relatively small Young's modulus, and which can be deposited by sputtering using the same target as that in the deposition process over the wafer.
Number | Date | Country | Kind |
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2009-273240 | Dec 2009 | JP | national |