JP6780572B2 - Film deposition equipment - Google Patents

Description

The technique disclosed herein relates to a film forming apparatus.

Patent Document 1 discloses a film forming apparatus that forms a film on the upper surface of a wafer using a raw material gas. The film forming apparatus of Patent Document 1 includes a housing, a rotary table arranged in the housing, a rotary shaft fixed to the rotary table in the housing, and a gas supply means for supplying raw material gas into the housing. ing. In the film forming apparatus of Patent Document 1, the wafer is rotated by rotating the rotary table while the wafer is arranged on the rotary table. Further, while the wafer is rotating, the raw material gas is supplied into the housing by the gas supply means. The raw material gas is supplied from the outer peripheral side to the central side of the rotating wafer. A film is formed on the upper surface of the wafer by the raw material gas supplied into the housing.

Japanese Unexamined Patent Publication No. 2012-178613

In the film forming apparatus of Patent Document 1, the raw material gas supplied into the housing by the gas supply means may be pushed back to the outer peripheral side of the wafer by the centrifugal force of the rotating wafer. Then, the raw material gas is not uniformly supplied to the entire upper surface of the wafer, and the thickness of the film formed on the upper surface of the wafer becomes non-uniform. Therefore, the present specification provides a technique capable of uniformly approaching the amount of the raw material gas supplied to the upper surface of the wafer over the entire upper surface of the wafer.

The film forming apparatus disclosed in the present specification can form a film on the upper surface of a wafer by using a raw material gas. The film forming apparatus includes a motor, a first housing, a second housing arranged under the first housing, a third housing arranged under the second housing, and the first housing. A rotary table arranged inside, a rotary shaft fixed to the rotary table in the first housing and extending in the vertical direction from the inside of the first housing to the inside of the second housing, and the second. A through hole formed in the side wall of the housing and a belt that passes through the through hole and extends laterally from the inside to the outside of the second housing, and rotates the motor outside the second housing. 2 The belt transmitted to the rotating shaft in the housing, the nozzle for supplying raw material gas toward the center of the upper surface of the wafer arranged on the rotating table in the first housing, and the first. A gas flow path that is connected to the housing and the third housing and sends the raw material gas in the first housing into the third housing, and a gas formed in the third housing on an extension line of the rotation shaft. It includes a discharge port and a pump that sucks the raw material gas in the third housing through the gas discharge port.

In the above-mentioned film forming apparatus, when the motor rotates, the rotation of the motor is transmitted to the rotating shaft via the belt. The rotation of the motor outside the second housing is transmitted to the rotating shaft inside the second housing via the belt. Further, when the rotating shaft is rotated by the rotation of the motor, the rotating table fixed to the rotating table in the first housing rotates. When the turntable rotates, the wafer placed on the turntable rotates. Further, in the above-mentioned film forming apparatus, the raw material gas is supplied from the nozzle toward the center of the upper surface of the wafer while the wafer is rotating. The raw material gas supplied toward the center of the upper surface of the wafer flows along the upper surface of the wafer. The raw material gas flows from the center of the wafer to the outer periphery due to the centrifugal force of the rotating wafer. After that, the raw material gas is sent from the inside of the first housing to the inside of the third housing via the gas flow path connected to the first housing and the third housing. The raw material gas sent into the third housing is sucked by the pump and discharged to the outside of the third housing. The pump sucks the raw material gas through the gas discharge port formed on the extension line of the rotating shaft.

According to such a configuration, the raw material gas supplied from the nozzle flows from the center of the wafer to the outer periphery in the first housing, and then flows from the inside of the first housing to the third housing via the gas flow path. It flows in. Further, the raw material gas that has flowed into the third housing flows toward the extension line of the rotary shaft in the third housing by being sucked into the pump through the gas discharge port formed on the extension line of the rotary shaft. I will go. Therefore, the flow of the raw material gas first goes from the central portion side of the wafer to the outer peripheral portion side in the first housing, and then goes from the outer peripheral portion side to the central portion side in the third housing. That is, the direction of the flow of the raw material gas is in the order of the central portion → the outer peripheral portion → the central portion. This way of flowing the raw material gas makes it difficult for the amount of the raw material gas flowing along the upper surface of the wafer to become non-uniform over the entire upper surface of the wafer. Therefore, the amount of the raw material gas supplied to the upper surface of the wafer can be made uniform over the entire upper surface of the wafer. Further, the thickness of the film formed on the upper surface of the wafer can be made uniform.

The cross-sectional view which shows the outline of the film forming apparatus. The perspective view which shows the outline of the rotary table. A cross-sectional view showing a main part III of FIG. The figure which shows the lower surface of the 2nd housing (the IV-IV sectional view of FIG. 1).

The film forming apparatus 2 according to the embodiment is a CVD (Chemical Vapor Deposition) apparatus that forms a thin film on the upper surface of a semiconductor wafer using a raw material gas. The film forming apparatus 2 forms a thin film on the upper surface of the semiconductor wafer by using, for example, a metal-based raw material gas. The raw material gas is, for example, a gas made from gallium, a gas made from aluminum, or the like.

As shown in FIG. 1, the film forming apparatus 2 is arranged under the motor 100, the first housing 10, the second housing 20 arranged under the first housing 10, and the second housing 20. The third housing 30 is provided. Further, the film forming apparatus 2 includes a rotary table 50 arranged in the first housing 10 and a rotary shaft 51 fixed to the rotary table 50 in the first housing 10. Further, the film forming apparatus 2 includes a gas guide 40 arranged in the first housing 10.

The motor 100 of the film forming apparatus 2 is arranged outside the first housing 10, the second housing 20, and the third housing 30. The motor 100 is arranged next to the second housing 20. The motor 100 rotates the rotation shaft 51 via a rotation transmission mechanism 60 described later.

The first housing 10 houses the rotary table 50 and the gas guide 40. A gas supply pipe 91 is connected to the upper part of the first housing 10. The gas supply pipe 91 is connected to the gas supply source 92. The gas supply source 92 supplies a raw material gas for forming a thin film on the upper surface 101 of the semiconductor wafer w in the first housing 10. The raw material gas supplied by the gas supply source 92 is supplied into the first housing 10 through the gas supply pipe 91. A first suction pipe 83 is connected to the upper part of the first housing 10. The first suction pipe 83 is connected to the first pump 81. The first pump 81 sucks air to create a vacuum inside the first housing 10. The air in the first housing 10 is sucked by the first pump 81 through the first suction pipe 83.

A shaft support housing 15 is fixed to the lower part of the first housing 10. The shaft support housing 15 is formed with an upper opening 16 and a lower opening 17. An upper bearing 85 and a lower bearing 86 are arranged in the shaft support housing 15. Further, a gas discharge port 19 is formed in the lower part of the first housing 10. The gas discharge port 19 communicates with the gas flow path 21 of the second housing 20, which will be described later.

A heating coil 90 is arranged around the first housing 10. The heating coil 90 surrounds the first housing 10. The heating coil 90 heats the rotary table 50 arranged in the first housing 10 in a non-contact manner. The heating coil 90 heats the rotary table 50 by the principle of high frequency induction heating. In high-frequency induction heating, a magnetic field is generated by the current flowing through the coil (heating coil 90), and the action of the magnetic field causes a current to flow through the object to be heated (rotary table 50), thereby generating Joule heat in the object to be heated. To do. The rotary table 50 self-heats due to high frequency induction heating. Since the principle of high-frequency induction heating is known, detailed description thereof will be omitted.

As shown in FIG. 2, the rotary table 50 arranged in the first housing 10 is formed in a disk shape. The rotary table 50 is made of a conductor (for example, metal, carbon, etc.). The rotary table 50 has thermal conductivity. A disk-shaped wafer w is arranged on the rotary table 50.

The rotary table 50 includes a plurality of support members 70. The plurality of support members 70 are arranged at intervals in the rotary table 50. The tip portions 72 of the plurality of support members 70 project upward from the upper surface of the rotary table 50. Wafers w are arranged on the plurality of tip portions 72. The wafer w is supported by the plurality of support members 70.

A plurality of stoppers 3 are fixed to the rotary table 50. The plurality of stoppers 3 are arranged side by side at intervals along the circumferential direction of the rotary table 50. The plurality of stoppers 3 surround the wafer w arranged on the rotary table 50. The plurality of stoppers 3 come into contact with the outer peripheral surface of the wafer w to support the wafer w.

A rotary shaft 51 is fixed to the rotary table 50. The rotation shaft 51 is arranged so as to be coaxial with the rotation center 52 of the rotation table 50. The upper end of the rotary shaft 51 is fixed to the rotary table 50. The rotation shaft 51 extends in the vertical direction. As shown in FIG. 1, the rotating shaft 51 is arranged from the inside of the first housing 10 to the inside of the second housing 20. The lower end of the rotation shaft 51 is fixed to the rotation transmission mechanism 60. The rotary shaft 51 is fixed to the rotary table 50 in the first housing 10 and fixed to the rotary transmission mechanism 60 in the second housing 20. Further, the rotating shaft 51 is inserted into the shaft support housing 15. The rotating shaft 51 is inserted into the upper opening 16, the upper bearing 85, the lower bearing 86, and the lower opening 17 of the shaft support housing 15. A seal member 18 is arranged between the rotating shaft 51 and the upper opening 16 of the shaft support housing 15. The rotating shaft 51 is rotatably supported by the shaft support housing 15.

The gas guide 40 arranged in the first housing 10 includes a nozzle 42 and a cover member 41. The nozzle 42 and the cover member 41 are integrally formed. The gas guide 40 is arranged above the rotary table 50. The gas guide 40 is fixed to the upper part of the first housing 10 via a connecting member 75. A gas flow path 76 is formed in the connecting member 75. The material of the gas guide 40 is preferably resistant to high temperatures and is non-conductive. As the material of the gas guide 40, for example, boron nitride can be used.

As shown in FIG. 3, the nozzle 42 of the gas guide 40 is arranged above the center of the rotary table 50. The nozzle 42 extends in the vertical direction. A gas flow path 43 is formed in the nozzle 42. The gas flow path 43 extends in the vertical direction. The gas flow path 43 of the nozzle 42 is connected to the gas flow path 76 of the connecting member 75. The nozzle 42 is connected to the gas supply pipe 91 via a connecting member 75. The raw material gas supplied by the gas supply pipe 91 is supplied to the nozzle 42 via the connecting member 75. The gas flow path 43 of the nozzle 42 opens toward the center of the rotary table 50. The nozzle 42 supplies the raw material gas toward the upper surface 101 of the wafer w arranged on the rotary table 50. The nozzle 42 supplies the raw material gas toward the center of the upper surface 101 of the wafer w.

The cover member 41 of the gas guide 40 is fixed to the lower end of the nozzle 42. The cover member 41 is fixed to the outer peripheral portion of the nozzle 42. The cover member 41 is generally formed in a disk shape. The cover member 41 is arranged above the rotary table 50. The cover member 41 covers the upper surface of the rotary table 50. When the wafer w is placed on the rotary table 50, the cover member 41 covers the upper surface 101 of the wafer w.

As shown in FIG. 1, the second housing 20 is fixed to the lower part of the first housing 10. Further, the second housing 20 is fixed to the lower part of the shaft support housing 15. The second housing 20 is arranged between the first housing 10 and the third housing 30. The second housing 20 is arranged to secure a space between the first housing 10 and the third housing 30. The second housing 20 functions as a spacer. The lower end of the rotating shaft 51 is arranged in the second housing 20.

A plurality of gas flow paths 21 are formed in the second housing 20. Each gas flow path 21 penetrates the second housing 20 in the vertical direction. Each gas flow path 21 is connected to the first housing 10 and the third housing 30. Each gas flow path 21 sends the raw material gas in the first housing 10 into the third housing 30. As shown in FIG. 4, the plurality of gas flow paths 21 are formed side by side at intervals along the circumferential direction of the second housing 20. The plurality of gas flow paths 21 are formed at positions surrounding the rotating shaft 51. Grooves 24 are formed on the upper surface and the lower surface of the second housing 20, respectively. Each groove 24 communicates with a plurality of gas flow paths 21. Each groove 24 extends along the circumferential direction of the second housing 20.

As shown in FIG. 1, a through hole 22 is formed in the side wall 23 of the second housing 20. The through hole 22 penetrates the lateral wall 23 of the second housing 20 in the lateral direction. The inside and outside of the second housing 20 communicate with each other through a through hole 22 formed in the side wall 23. A part of the rotation transmission mechanism 60 for rotating the rotation shaft 51 is arranged in the through hole 22.

The rotation transmission mechanism 60 includes a first pulley 62, a belt 61, and a second pulley 63. The first pulley 62 is fixed to the motor 100. When the motor 100 rotates, the first pulley 62 rotates. The second pulley 63 is fixed to the rotating shaft 51. When the second pulley 63 rotates, the rotating shaft 51 rotates. The belt 61 is arranged from the first pulley 62 to the second pulley 63. The belt 61 extends laterally and passes through a through hole 22 formed in the second housing 20. The belt 61 is arranged inside and outside the second housing 20 through the through hole 22. One end of the belt 61 is arranged outside the second housing 20, and the other end of the belt 61 is arranged inside the second housing 20. The rotation transmission mechanism 60 transmits the rotation of the motor 100 to the rotation shaft 51 via the first pulley 62, the belt 61, and the second pulley 63. When the motor 100 rotates, the first pulley 62, the belt 61, and the second pulley 63 rotate. As a result, the rotation shaft 51 rotates.

The third housing 30 is fixed to the lower part of the second housing 20. The inside of the first housing 10 and the inside of the third housing 30 communicate with each other through the gas flow path 21 formed in the second housing 20. A gas discharge port 31 is formed in the lower part of the third housing 30. The gas discharge port 31 is formed at the center of the third housing 30 in the lateral direction. The gas discharge port 31 is formed in the third housing 30 on an extension line of the rotating shaft 51 extending in the vertical direction. The gas discharge port 31 is formed coaxially with the rotating shaft 51.

A second suction pipe 84 is connected to the gas discharge port 31 of the third housing 30. The second suction pipe 84 is connected to the second pump 82. The second pump 82 sucks the raw material gas in the third housing 30 through the second suction pipe 84. Further, the second pump 82 is connected to the first pump 81 via the third suction pipe 87. The second pump 82 can suck the air in the first housing 10 in cooperation with the first pump 81.

Next, the operation of the film forming apparatus 2 having the above configuration will be described. In the film forming apparatus 2, the first pump 81 first sucks the air in the first housing 10 in order to create a vacuum in the first housing 10. Further, in the film forming apparatus 2, the motor 100 rotates in order to rotate the wafer w arranged in the first housing 10. When the motor 100 rotates, the rotation of the motor 100 is transmitted to the rotation shaft 51 via the rotation transmission mechanism 60. The rotation transmission mechanism 60 transmits the rotation of the motor 100 to the rotation shaft 51 via the first pulley 62, the belt 61, and the second pulley 63. The rotation of the motor 100 arranged outside the second housing 20 is transmitted to the rotating shaft 51 arranged inside the second housing 20. As a result, the rotation shaft 51 rotates. When the rotary shaft 51 rotates, the rotary table 50 fixed to the rotary shaft 51 rotates. The rotary table 50 arranged in the first housing 10 rotates. Further, when the rotary table 50 rotates, the wafer w arranged on the rotary table 50 rotates.

Further, in the film forming apparatus 2, the raw material gas for forming a thin film on the upper surface 101 of the wafer w is supplied from the gas supply source 92. The gas supply source 92 supplies the raw material gas into the first housing 10 through the gas supply pipe 91. The raw material gas supplied through the gas supply pipe 91 is supplied from the gas supply pipe 91 to the nozzle 42 of the gas guide 40 via the connecting member 75. The nozzle 42 of the gas guide 40 supplies the raw material gas supplied from the gas supply pipe 91 toward the wafer w arranged in the first housing 10. The nozzle 42 of the gas guide 40 supplies the raw material gas toward the center of the upper surface 101 of the rotating wafer w.

The raw material gas supplied toward the upper surface 101 of the wafer w flows from the central portion to the outer peripheral portion of the wafer w due to the centrifugal force due to the rotation of the wafer w. After that, this raw material gas flows from the inside of the first housing 10 into the third housing 30 through the gas flow path 21. The raw material gas in the first housing 10 is discharged into the third housing 30. Subsequently, the raw material gas in the third housing 30 is sucked by the second pump 82. The second pump 82 sucks the raw material gas through the gas discharge port 31 formed in the lower part of the third housing 30. As a result, the raw material gas in the third housing 30 is discharged to the outside of the third housing 30 through the gas discharge port 31.

According to the film forming apparatus 2 as described above, the raw material gas supplied from the nozzle 42 flows from the center portion to the outer peripheral portion of the wafer w in the first housing 10 due to the centrifugal force due to the rotation of the wafer w. go. After that, the raw material gas flows from the inside of the first housing 10 into the third housing 30 through the gas flow path 21 formed in the second housing 20. Subsequently, the raw material gas in the third housing 30 is sucked into the second pump 82 through the gas discharge port 31 formed on the extension line of the rotating shaft 51. As a result, the raw material gas flows in the third housing 30 toward the extension line of the rotating shaft 51. Therefore, the flow of the raw material gas first goes from the central portion side of the wafer w to the outer peripheral portion side, and then goes from the outer peripheral portion side to the central portion side. That is, the direction of the flow of the raw material gas is in the order of the central portion → the outer peripheral portion → the central portion. Due to this flow of the raw material gas, the amount of the raw material gas flowing along the upper surface 101 of the wafer w is less likely to become non-uniform over the entire upper surface 101 of the wafer w. Therefore, the amount of the raw material gas supplied to the upper surface 101 of the wafer w can be made uniform over the entire upper surface of the wafer w. As a result, the thickness of the film formed on the upper surface 101 of the wafer w by the raw material gas can be made uniform.

Although one embodiment has been described above, the specific embodiment is not limited to the above embodiment. In the following description, the same reference numerals will be given to the same configurations as those in the above description, and the description thereof will be omitted.

Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples illustrated above. The technical elements described herein or in the drawings exhibit their technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques illustrated in the present specification or drawings can achieve a plurality of purposes at the same time, and achieving one of the purposes itself has technical usefulness.

2: Formation apparatus 10: First housing 15: Shaft support housing 20: Second housing 21: Gas flow path 22: Through hole 23: Side wall 30: Third housing 31: Gas discharge port 40: Gas guide 41: Cover member 42: Nozzle 50: Rotating table 51: Rotating shaft 60: Rotation transmission mechanism 61: Belt 62: First pulley 63: Second pulley 70: Support member 72: Tip 81: First pump 82: Second pump 83: Second 1 suction pipe 84: 2nd suction pipe 87: 3rd suction pipe 90: heating coil 91: gas supply pipe 92: gas supply source 100: motor 101: top surface

Claims (1)

A film forming apparatus that forms a film on the upper surface of a wafer using raw material gas.
With the motor
1st housing and
A second housing arranged under the first housing and
A third housing arranged under the second housing and
The rotary table arranged in the first housing and
A rotating shaft fixed to the rotary table in the first housing and extending in the vertical direction from the inside of the first housing to the inside of the second housing.
Through holes formed in the side wall of the second housing and
A belt that passes through the through hole and extends laterally across the inside and outside of the second housing, and transmits the rotation of the motor outside the second housing to the rotation shaft inside the second housing. When,
A nozzle for supplying raw material gas toward the center of the upper surface of the wafer arranged on the rotary table in the first housing, and
A gas flow path that is connected to the first housing and the third housing and sends the raw material gas in the first housing into the third housing.
A gas outlet formed in the third housing on an extension of the rotating shaft,
A film forming apparatus including a pump for sucking a raw material gas in the third housing through the gas discharge port.

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