JP4509369B2 - Plasma assisted sputter deposition system - Google Patents

Description

[0001]
[Field of industrial use]
The present invention relates to a plasma assisted sputter deposition apparatus, and more particularly, to a plasma assisted sputter deposition apparatus having a new shield configuration in a reaction vessel for improved plasma stability and most reduced particle contamination to plasma.
[0002]
[Prior art]
Plasma-assisted sputter deposition of films such as Al, Cu, TaN, etc. on a Si wafer is an essential step in the microelectronic industry. With increasing diameter of Si wafers, single wafer processing modules with higher radio frequency (rf) power supplies have become an application stage. However, increasing the high frequency power is not always a practical solution because it requires an increase in deposition rate and the plasma becomes unstable at higher high frequency power. This unstable plasma creates an electrical spark (electrical spark) and causes particle contamination to the plasma. Therefore, proper reaction vessel design that provides improved plasma stability is important.
[0003]
  Problems in the plasma-assisted sputter deposition apparatus are explained using the conventional apparatus shown in FIG. This sputtering apparatus includes a reaction vessel 150, an upper electrode 151, two metal shields 152 and 153, a wafer holder 154 on which a wafer 155 is mounted, and a cylindrical side wall 156 as main elements. The thickness of all parts associated with the reaction vessel 150 is exaggerated in FIG. The upper electrode 151 is usually made by two overlapping circular plates 151a, 151b, where the upper plate 151a is made of a metal such as Al (aluminum) and the lower plate 151b is made of a sputtering material. In this case, the lower plate 151b is called a target plate. The upper plate 151 is fixed to the upper part of the reaction vessel 150 via a dielectric ring member 149. The bottom surface of the upper electrode 151 is opposed to the upper surface of the wafer 155. Further, the upper plate 151a is connected to a high frequency power source 157 via a matching circuit 158 so that high frequency power is supplied. That is, a high-frequency current that operates at a frequency in the range of 10 MHz to 100 MHz is applied to the upper electrode 151 via the matching circuit 157, and plasma is generated by a capacitively coupled mechanism. The upper electrode 151 acts as a high frequency electrode. When the plasma is ignited, a self-bias voltage is generated in the upper electrode 151. The value of the self-bias voltage depends on the frequency of the applied high-frequency current and applied high-frequency power. Increasing the high frequency and decreasing the applied high frequency power result in a decrease in the self-bias voltage. Conversely, a decrease in high frequency frequency and an increase in applied high frequency power result in an increase in self-bias voltage. In addition to these two parameters, the pressure and hardware configuration employed for plasma generation affects the self-bias voltage. Usually, for efficient sputtering, approximately−It is expected to have a self-bias voltage of 100V or higher. If the self-bias voltage is low, an additional DC voltage is applied to the upper electrode 151 from a voltage source to obtain a sufficient sputtering rate. This DC voltage supply is not shown in FIG.
[0004]
The metal shield 152 is fixed to the cylindrical side wall 156, and the other metal shield 153 is fixed to the outer cover 159 of the wafer holder 154. The cylindrical side wall 156 and the outer cover 159 of the wafer holder 154 are electrically grounded. Therefore, the two metal shields 152 and 153 are electrically grounded.
[0005]
The wafer holder 154 shown in FIG. 6 is at the wafer processing level (height). Once processing on the wafer 155 is complete, the wafer holder 154 is moved downward to replace the wafer to be processed. Therefore, the wafer holder 154 is repeatedly moved up and down while the wafer processing is being performed. That is, the metal shield 153 is repeatedly moved up and down in the same manner every time the wafer is replaced. According to the illustration according to FIG. 6, the support cylindrical member 161 supports the wafer holder 154. A moving mechanism for moving the wafer holder 154 is not shown in FIG.
[0006]
The wafer holder 154 includes a three-layer dielectric ring 162, a lower electrode 163 supported by the dielectric ring 162, and a wafer fixing mechanism 164. The process chamber 165 is formed on the upper side of the wafer holder 154. In addition, a vacuum chamber 166 is formed in the lower portion of the reaction vessel 150. The vacuum chamber 166 has a wafer transfer port 167, a process gas introduction hole 168 formed in the bottom plate 169, and an exhaust port 170. The exhaust port 170 is connected to an exhaust mechanism (vacuum pump) not shown in FIG.
[0007]
[Problems to be solved by the invention]
There are two main problems associated with the conventional configuration described above.
[0008]
The first problem is, in particular, the occurrence of electrical sparks on the metal shield 153. When the plasma is ignited in the gap between the target plate 151b and the wafer holder 154, the surface of the wafer 155 is in an electrically floating state, and thus has a higher potential. The metal shield 153 is in electrical ground and is in close proximity to the wafer 155. Thus, there is a higher potential difference between the wafer 155 and the metal shield 153. Since the surface area of the interaction between the metal shield 153 and the wafer 155 is small, the capacitance (C₁) Is also small as shown in FIG. Therefore, even if there is a small charge imbalance on the wafer surface, it causes an electrical spark between the wafer 155 and the metal shield 153. Once the electrical spark perturbs the stability of the plasma, the instability lasts for a few seconds as the electrical spark persists. Where electrical sparks occur, metal shield 152 or metal shield 153, usually made of Al, will dissolve and evaporate. This results in contamination of the sputter deposited film and target material.
[0009]
The second problem is related to particles. These particles are generated as a result of the film deposited from the metal shield 153 being peeled off. This is because the metal shield 153 receives a small vibration when moving up and down with the wafer holder 154 when exchanging each wafer. These vibrations weaken the bond between the deposited film and the metal shield 153, especially if there was contamination on the metal shield 153 in the initial stage. This results in peeling of the film deposited by sputtering on the metal shield 153 and contaminates the plasma, wafer surface, target surface, metal shield, and reaction vessel sidewall. In addition, these accumulated particles on the sidewalls, metal shield, and target plate trigger the generation of electrical sparks.
[0010]
An object of the present invention is to provide a plasma assisted sputter deposition apparatus that reduces the contamination of the sputter deposited film and the target material by maintaining the stability of the plasma and preventing the occurrence of electrical sparks.
[0011]
Another object of the present invention is to provide a plasma-assisted sputter deposition apparatus that prevents peeling of a film deposited on a metal shield by reducing the influence of small vibrations.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, a plasma assisted sputter deposition apparatus according to the present invention is configured as follows.
[0013]
A plasma-assisted sputter deposition apparatus according to the present invention (corresponding to claim 1) includes a reaction vessel including a process chamber and a vacuum chamber. The process chamber has an upper electrode including a target plate on the upper side. Plasma is generated in the process chamber based on the high frequency power supplied to the target plate, and the vacuum chamber has a process gas supply unit and an exhaust mechanism. The wafer holder is provided between the process chamber and the vacuum chamber, and includes a lower electrode, at least a dielectric ring, and a wafer fixing mechanism (for example, ESC). One wafer is mounted on the wafer fixing mechanism. Furthermore, the above-described apparatus is electrically floating with respect to the cylindrical side wall forming the side of the reaction vessel, the first metal shield fixed to the cylindrical side wall so as to cover the entire inner surface of the cylindrical side wall, and the wafer holder. A second metal shield having an inclined portion provided in a ring shape around the wafer and placed on the dielectric ring, and between the first and second metal shields And a third metal shield having a bent inner edge portion secured to the cylindrical side wall. The bent inner edge portion of the third metal shield faces the outer surface of the inclined portion of the second metal shield.
[0014]
In the above apparatus, preferably, the horizontal portion of the first metal shield is opposed to the horizontal portion of the third metal shield with a predetermined gap (gap).
[0015]
  In the above apparatus, the first metal shield and the first metal shield are preferably used.3The metal shield is made to be a single member.
[0016]
In the above apparatus, preferably, the process gas supplied to the vacuum chamber is supplied to the process chamber through a gas introduction hole of the third metal shield or a narrow gap between the third metal shield and the wafer holder.
[0017]
In the above device, preferably, the second metal shield and the third metal shield have a common surface area due to the increased capacitance between the two metal shields.
[0018]
In the above apparatus, the wafer holder is preferably provided so as to move up and down between a wafer processing level (height) and a wafer transfer level (height).
[0019]
In the above apparatus, the wafer holder is preferably fixed to the bottom of the reaction vessel so as to have its upper surface at the wafer transfer level.
[0020]
In the above apparatus, the first metal shield preferably has a window at the wafer transfer level for transferring the wafer.
[0021]
In the above apparatus, the window of the first metal shield preferably has a metal door that can move up and down.
[0022]
In the plasma-assisted sputter deposition apparatus according to the present invention having the above-described configuration, the third metal shield is fixed to the cylindrical side wall, and the second metal shield is disposed in an electrically floating state around the wafer. The problem which has arisen in connection with the apparatus of this can be solved. The surface area of interaction between the second metal shield disposed around the wafer and the third metal shield secured to the cylindrical sidewall is such that the capacitance between these two metal shields increases and Thereby, it is increased so as to strengthen the capacitive coupling of the return high-frequency current. In addition, the second metal shield placed around the wafer has a minimum surface area that is exposed to the plasma to minimize particle contamination.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments will be described with reference to the accompanying drawings. Details of the present invention will be made clear through the description of the embodiments.
[0024]
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a cross-sectional view of a two chamber plasma assisted sputter deposition apparatus. This sputter deposition apparatus has a reaction vessel 100, and the reaction vessel 100 includes an upper process chamber 101 and a lower vacuum chamber 102. Further, this sputter deposition apparatus is composed of an upper electrode 11, three metal shields 12, 13, 14, a wafer holder 15 on which a wafer 16 is disposed, and a cylindrical side wall 21 that forms the side wall of the upper process chamber 101. . The upper electrode 11 forms a ceiling plate of the process chamber 101. The upper electrode 11 is provided on the dielectric ring member 103.
[0025]
The metal shields 12 and 13 are fixed to the inner part of the cylindrical side wall 21. The upper edge of the metal shield 12 is coupled to the upper edge of the cylindrical side wall 21. The metal shield 12 has an almost cylindrical shape with a vertical portion 12 a and a lower horizontal portion 12 b and covers the inner surface of the cylindrical side wall 21. The outer edge of the metal shield 13 is fixed to the lower part of the cylindrical side wall 21. The metal shield 13 has three parts, that is, a horizontal part 13a located outside, a vertical part 13b located in the middle, and a bent part 13c located inside.
[0026]
The metal shield 14 is in an electrically floating state and is disposed around the wafer 16. The metal shield 14 has a ring-shaped inclined portion. The wafer holder 15 includes a lower electrode 17 and three ring-shaped dielectric members 18. These dielectric members 18 support the lower electrode 17. The wafer holder 15 is located between the upper process chamber 101 and the lower vacuum chamber 102, and divides the internal space of the reaction vessel 100 into the two chambers 101 and 102 as shown in FIG.
[0027]
Usually, the upper electrode 11 has a composite structure of a metal plate 11a and a target plate 11b. The target plate 11b is made of a material that needs to be sputtered. The metal plate 11 a is connected to the high frequency power source 19 through the matching circuit 20. Thus, the high frequency power supply 19 supplies high frequency power to the upper electrode 11.
[0028]
The two metal shields 12 and 13 are strongly fixed to the cylindrical side wall 21. Since the reaction vessel 100 is grounded, the metal shields 12 and 13 are in an electrically grounded state. A metal shield 14 disposed around the wafer 16 is placed on top of the three dielectric rings 18 thereby placing the metal shield 14 in an electrically floating state.
[0029]
  The thicknesses of these metal shields 12, 13, and 14 are not critical and are usually in the range of 2 to 10 mm. Metal shield12,1The diameter of 3 is not critical and depends on the size of the reaction vessel. For example, if the reaction vessel 100 is designed to process a wafer having a diameter of 200 mm, the diameter of the vertical portion 12a of the metal shield 12 is in the range of 350 to 450 mm. The inner diameter of the horizontal portion 12b of the metal shield 12 may be in the range of 300 to 450 mm. Usually, the outer diameter of the metal shield 13 is determined to be equal to the outer diameter of the vertical portion 12 a of the metal shield 12. The region of interaction of the horizontal portions 12b, 13a of each of the metal shields 12, 13 is such that they have a gap between them and a larger capacity (C₂It is important to maintain a value of about 10 mm or higher. This large capacitance thereby facilitates better high frequency current coupling from the metal shield 13 to the metal shield 12. The inner diameter of the horizontal portion 13 a of the metal shield 13 can vary depending on the diameter of the wafer holder 15. The distance between the vertical portion 13b of the metal shield 13 and the outer wall 22 of the wafer holder 15 is held as small as possible. Usually this spacing is kept at approximately 1 mm.
[0030]
  A partially enlarged cross-sectional view of the metal shield 14 is shown in FIG. 2 along with the peripheral hardware for the wafer holder 15. The inner diameter of the metal shield 14 is usually equal to the diameter of the wafer 16 or approximately 2 mm to 4 mm shorter than the diameter of the wafer. The outer diameter of the metal shield 14 is approximately 5 to 10 mm larger than the diameter of the wafer, but should be as small as possible to reduce the width of the metal shield 14. Thus, the metal shield 14 has an inclined portion. A suitable range for the width of the metal shield is approximately 5±3 mm. The cross-sectional shape of the metal shield 14 shown in FIG. 2 is not critical, and this shape can be changed without diminishing its expected attributes. The metal shield 14 is placed on the dielectric ring 18a. The spacing between the lower electrode 13 and the metal shield 14 is kept between approximately 2 mm and 4 mm in order to obtain better high frequency power coupling between the lower electrode 13 and the metal shield 14. This high frequency power coupling is important only when high frequency power is applied to the lower electrode 13. The dielectric ring 18a is disposed on the other dielectric ring 18b. A narrow horizontal space or gap 23 is created between these two dielectric rings 18a, 18b. The purpose of the narrow space 23 is to prevent the metal film deposited on the metal shield 14 and the dielectric rings 18a and 18b from being connected. The outside of the metal shield 14 is covered with a metal shield 13. The outer portion of the metal shield 14, which is covered by the metal shield 13, is slightly angled (angled portion 13c) as shown in FIG. The use of the bent portion 13c facilitates an increase in the surface area that interacts with the metal shield 13, which increases the capacitance between the two metal shields 13,14 (C₃). The common surface area between the metal shields 13, 14 is usually quite large and is taken to be greater than 2r when the wafer diameter is r. Again, the bent or inclined portions of the metal shield 14 reduce the surface area exposed to the plasma. Since the outer diameter of the metal shield 14 is smaller than the outer diameter of the wafer holder 15, the metal shield 13 must have a bent portion 13c as well. Usually, the capacitance between the metal shields 12 and 13 (C₂), Capacitance between metal shields 13 and 14 (C₃) Is C₂> C₃≫C₁It is determined as
[0031]
The distance from the target plate 11b to the horizontal portion 13a of the metal shield 13 is in the range of 80 mm to 150 mm. If there are no other problems, it is recommended to increase this distance to approximately 150 mm. The purpose is to increase the surface area of the high frequency current collecting surface, which is extremely important for a stable plasma. If the wafer processing level is approximately 100 mm below the target plate 11b, the metal shield 13 can be made without the bent portion 13c. That is, the metal shield 13 is made as a flat plate or a horizontal plate.
[0032]
The wafer 16 is disposed on the lower electrode 17 provided on the wafer holder 15. The lower electrode 17 may or may not include an electromagnetic chuck (ESC) 24 for fixing the wafer 16 on the lower electrode 17. The lower electrode 17 is placed on a dielectric ring (or plate) 18c. Thus, it is electrically isolated from the rest of the reaction vessel 100. The lower electrode 17 may or may not be supplied with high frequency power. If the lower electrode 17 is not supplied with high frequency power, it is either electrically isolated or is electrically grounded.
[0033]
The wafer holder 15 moves up and down when each wafer is replaced. When the wafer holder 15 is at the wafer processing level as shown in FIG. 1, the reaction vessel 100 has a process chamber defined by the target plate 11b, metal shields 12, 13, 14, and other metal shields 25, wafer 16. 101 and a vacuum chamber 102 located below the process chamber 101. When the wafer holder 15 is moved below the wafer replacement level, both the process chamber 101 and the vacuum chamber 102 become a single chamber.
[0034]
Before the film formation by sputtering is started, the wafer holder 15 moves to the wafer replacement level, and the inside of the reaction vessel 100 is approximately 10 minutes.^-8Exhaust to the basic pressure of Torr. This is important in venting all undesirable gases remaining on the reaction vessel 100 and its inner walls.
[0035]
The metal plate 11 a of the upper electrode 11 is connected to a high frequency (rf) power source or a high frequency generator 19 through a matching circuit 20. Therefore, the upper electrode 11 is supplied with a high frequency current from the high frequency power source 19 via the matching circuit 20. The frequency of the high frequency current is not critical, but can vary between 10 MHz and 100 MHz. When a high frequency current is applied to the upper electrode 11, plasma is generated below the target plate 11b by a capacitive coupling mechanism. The ions in the plasma are accelerated toward the target plate 11b due to the self-bias voltage of the high-frequency upper electrode 11, and the target material is sputtered from the target plate 11b. The high frequency current coming from the upper electrode 11 to the plasma is collected by the metal shields 12, 13, 14, 25 and the wafer 16. If the lower electrode 17 is in an electrically floating state, most of the high-frequency current is collected by the metal shields 12, 13, 14, 25. The high frequency current collected by the metal shield 13 flows to the metal shield 12 via capacitive coupling. There are two ways to increase the effect of capacitive coupling. The first method is to increase the surface area of the horizontal portion 12b of the metal shield 12, which interacts with the metal shield 13 at the desired gap. The second method is to reduce the gap between the horizontal portions 12b and 13a of the metal shields 12 and 13. Both of these two methods are C₂Increase. The gap between the horizontal portions of the metal shields 12 and 13 is preferably as small as about 0.5 mm. The high frequency current collected by the metal shield 12 then flows to the metal shield 25 and thereby to the grounded terminal of the matching circuit 20.
[0036]
If the deposition of the sputtered film on the wafer 16 mounted on the wafer holder 15 is purely a physical process (eg Cu sputtering), a process gas (eg Ar) is produced on the side wall 21 or the bottom wall plate 27. Then, the gas is supplied into the vacuum chamber 102 through the gas inlet 26. The process gas then enters the process chamber 101 via a number of holes 28 made in the horizontal portion 13 a of the metal shield 13. Furthermore, the process gas likewise flows into the process chamber 101 through a narrow gap between the wafer holder 15 and the metal shield 13.
[0037]
Once the process on the wafer 16 is complete, the wafer holder 16 is moved down to replace the wafer to be processed. Wafer holder 15 is repeatedly moved up and down during wafer processing. The support cylindrical member 29 supports the wafer holder 15. In FIG. 1, a moving mechanism for moving the wafer holder 15 is not shown.
[0038]
The vacuum chamber 102 has a wafer transfer port 30 and an exhaust port 31. The exhaust port 31 is connected to an exhaust mechanism (vacuum pump) not shown in FIG.
[0039]
In the above-described configuration, since the two metal shields 13 and 14 share a large common surface area, the high-frequency current in the metal shield 14 is easily coupled to the metal shield 13. Furthermore, the surface quality of the metal rings 12, 13, 14, 25 does not change with time other than the deposition of the sputtered film. Therefore, the occurrence of unbalanced electrical changes on these metal shields is eliminated, especially in the areas where the metal shield 13 and the metal shield 14 interact with each other. This prevents the start of electrical sparks.
[0040]
The metal shield 14 moves up and down together with the wafer holder 15 when each wafer is replaced. However, since the surface area of the metal shield 14 where the film is deposited is minimized, particle contamination due to peeling of the deposited film is also minimized as well.
[0041]
As explained above, a plasma assisted sputter deposition apparatus with an improved shield configuration creates a stable plasma environment without creating electrical sparks within the reaction vessel, and against the plasma and wafer surfaces. Minimize particle contamination.
[0042]
Next, a second embodiment of the present invention will be described. The configuration of the second embodiment is a modification of the first embodiment. A schematic diagram of the second embodiment is shown in FIG. According to the second embodiment, the single metal shield 32 is replaced with two metal shields 12 and 13 fixed to the side wall of the reaction vessel 100. Except for this change, all other configurations are the same as those given in the first embodiment. The use of a single metal shield 32 instead of the two metal shields 12 and 13 increases the flow of high frequency current back to the ground terminal of the high frequency input port, thus making the plasma more stable.
[0043]
A third embodiment of the present invention will be described with reference to FIG. The third embodiment is also a modification of the first embodiment. Here, only the configuration of the metal shields 12, 13 is changed. Therefore, only the configuration of the metal shields 12, 13 will be described. The metal shields 12 and 13 are fixed to the side wall of the reaction vessel 100 as described in the first embodiment. In this embodiment, the metal shield 12 is made without having a horizontal portion. Instead, the metal shield 13 having the horizontal portion 13a, the vertical portion 13b, and the bent portion 13c is made with the vertical portion 13d at the outermost diameter. The vertical part 13d outside the metal shield 13 interacts with the metal shield 12 having only the vertical part. Although this configuration does not have much difference compared to the first embodiment, this configuration shows that there are other possible configurations of metal shields without minimizing the expected attributes. Shown only in meaning. Furthermore, combining and removing the metal shield is relatively easy with respect to this configuration.
[0044]
Next, a fourth embodiment will be described with reference to FIG. 5 showing a cross-sectional view of the reaction vessel. In the configuration of the fourth embodiment, the metal shields 12, 13, 14, 25 and the wafer holder 15 are fixed to the reaction vessel. A small window 33 is created in the vertical portion 12a of the metal shield 12 to load and remove the wafer 16 to be processed. Reference numeral 34 denotes a wafer take-in / out port. The position of the small window 33 made in the metal shield 12 corresponds to the wafer take-in / out port 34. The height and width of the small window are approximately 8 mm and 210 mm, respectively. During wafer processing, this small window 33 is closed by a door 35 that can move up and down. When it is necessary to replace the wafer 16, this door 35 is opened by moving downward and the wafer is replaced. The door 35 is connected to a rod 36 that is moved up and down by a motor or other drive mechanism 37. The door 35 and the rod 36 are made of metal and are grounded. When the door 35 is closed, a very narrow gap, for example, 1 mm, exists between the door 35 and the metal shield 12. That is, the door 35 is not in contact with the metal shield 12. This is because if the door 35 is repeatedly contacted with the metal shield 12 at any time during the wafer replacement stage, the metal shield 12 is subjected to vibrations that will peel off the deposited film. The dimension of the door 35 is usually taken larger than the dimension of the window 33. This prevents the plasma from expanding through the narrow gap between the door 35 and the metal shield 12.
[0045]
According to the above-described configuration of the fourth embodiment, the wafer holder 15 is fixed to the bottom of the reaction vessel in order to minimize the moving part in the reaction vessel. The only moving part in the reaction vessel is the door 35 that moves up and down during wafer replacement. Since the wafer holder 15 and the metal shields 12, 13, and 25 are fixed to the reaction vessel portion, the outer diameter of the metal shield 14 does not necessarily have to be small, and can be enlarged in this way. Except for the above-described modifications, all other configurations are substantially the same as those described in the first embodiment. However, in comparison with the first embodiment, the vacuum chamber 102 is relatively small. Using a fixed metal shield and wafer holder increases the reproducibility of the sputtering process and reduces the possibility of particle contamination.
[0046]
Furthermore, the metal shields 12, 13 in the fourth embodiment can be replaced by a single metal shield, which is fixed to the cylindrical side wall. This improves the flow of return high frequency current to the ground terminal of the high frequency matching circuit.
[0047]
[Technical effects of the invention]
The plasma assisted sputter deposition apparatus according to the present invention prevents the peeling of the film deposited on the metal shield by preventing the occurrence of electrical sparks and reducing the influence of small vibrations. Contamination of the film and target material can be reduced.
[Brief description of the drawings]
FIG. 1 is a sectional view of a plasma assisted sputter deposition apparatus according to a first embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view of a peripheral portion of a wafer holder in the first embodiment.
FIG. 3 shows a cross-sectional view of a second embodiment of the present invention in which the metal shield configuration is modified.
FIG. 4 shows a cross-sectional view of a third embodiment of the present invention in which the configuration of the metal shield is modified.
FIG. 5 shows a cross-sectional view of a fourth embodiment of the present invention, in which a metal shield and a wafer holder are fixed to a reaction vessel.
FIG. 6 is a cross-sectional view of a conventional plasma-assisted sputter deposition apparatus.
FIG. 7 shows an enlarged view of the edge portion of the wafer holder shown in FIG.
[Explanation of reference numerals in the figure]
          11 Upper electrode
          11a metalplate
          11b Target plate
          12, 13, 14 Metal shield
          15 Wafer holder
          16 wafers
          17 Lower electrode
          18 Dielectric ring
          21 Cylindrical side wall
          100 reaction vessel
          101 process chamber
          102 Vacuum chamber

Claims (9)

A process chamber and a vacuum chamber, the process chamber having a first electrode with a target plate on the upper side, and plasma is generated based on radio frequency (rf) power supplied to the target plate in the process chamber; The vacuum chamber includes a reaction gas supply unit and a reaction vessel including an exhaust mechanism;
A wafer holder disposed between the process chamber and the vacuum chamber and including a second electrode, a dielectric ring, a wafer fixing mechanism, and a wafer mounted thereon;
In a plasma assisted sputter deposition apparatus comprising:
A cylindrical side wall forming the side of the reaction vessel;
A first metal shield secured to the cylindrical side wall so that the cylindrical side wall also covers the inner surface;
A second metal shield disposed on the wafer holder in an electrically floating state so as to be disposed around the wafer and in a ring shape on the dielectric ring;
A third metal shield secured to the cylindrical side wall to be disposed between the first metal shield and the second metal shield and having a bent inner edge;
In the above, the bent inner edge portion of the third metal shield is opposed to the outer surface of the inclined portion of the second metal shield.   2. The plasma assisted sputter deposition apparatus according to claim 1, wherein the horizontal portion of the first metal shield is opposed to the horizontal portion of the third metal shield with a predetermined gap. 2. The plasma assisted sputter deposition apparatus according to claim 1, wherein the first metal shield and the third metal shield are formed as a single member.   The process gas supplied to the vacuum chamber is introduced into the process chamber through a gas introduction hole of the third metal shield or a narrow gap between the third metal shield and the wafer holder. The plasma-assisted sputtering film forming apparatus according to any one of claims 1 to 3.   The plasma assisted sputter deposition apparatus of claim 2, wherein the second metal shield and the third metal shield have a common surface area for increased capacitance between the two metal shields. .   2. The plasma-assisted sputter deposition apparatus according to claim 1, wherein the wafer holder is provided so as to move up and down between a wafer processing height and a wafer transfer height.   2. The plasma assisted sputter deposition apparatus according to claim 1, wherein the wafer holder is fixed to the bottom of the reaction vessel so as to have an upper surface at a wafer transfer height.   8. The plasma assisted sputter deposition apparatus according to claim 7, wherein the first metal shield has a window at a height of the wafer transfer for transferring the wafer.   9. The plasma-assisted sputter deposition apparatus according to claim 8, wherein the window of the first metal shield has a metal door that can move up and down.

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