JP2012169409A - Semiconductor manufacturing device and semiconductor device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor manufacturing device capable of removing deposit such as a coat to a side wall of a chamber of the semiconductor manufacturing device, in a short time as compared with a conventional one.SOLUTION: A shower plate 13 has a main surface portion 131 including a placing position of a substrate, and having a flat plate shape generally parallel with a substrate surface; and a side surface portion 132 having a cylindrical shape, connected to an outer peripheral portion of the main surface portion 131 at one end, and connected to a chamber 11 at the other end. On the main surface portion 131, a plurality of gas supply holes 131a for blowing out gas to a substrate holding portion 12 side is provided. On the side surface portion 131, a plurality of gas supply holes 132a for blowing out gas toward a side wall of the chamber 11 is provided. The shower plate 13 is equipped with a partitioning wall 134 which partitions a main gas supply space 135 for making the gas flow to the substrate holding portion 12 side through the gas supply holes 131a, and a sub gas supply space 136 for making the gas flow to the side wall side of the chamber 11 through the gas supply holes 132a.

Description

  FIELD Embodiments described herein relate generally to a semiconductor manufacturing apparatus and a semiconductor device manufacturing method.

  In a conventional CVD (Chemical Vapor Deposition) apparatus, a film forming gas supplied into a chamber is supplied onto a wafer in a shower shape with a shower plate, the wafer is brought to a predetermined temperature, and a desired film is formed on the wafer. It was. In addition, after the wafer on which the film has been formed is carried out of the CVD apparatus, a cleaning gas is introduced into the chamber to remove the film and reaction byproducts that have adhered to the chamber.

JP 2004-76023 A

  However, in the prior art, for example, since cleaning is simply performed by introducing a cleaning gas into the chamber through a shower plate, there is a problem that it takes time to remove the coating formed on the side wall of the chamber. .

  One embodiment of the present invention provides a semiconductor manufacturing apparatus and a method of manufacturing a semiconductor device that can remove deposits such as a coating on a sidewall of a chamber of the semiconductor manufacturing apparatus in a shorter time than conventional. With the goal.

  According to one embodiment of the present invention, a semiconductor manufacturing apparatus including a chamber, a gas supply unit, a substrate holding unit, a shower plate, and a plasma generation unit is provided. The gas supply means supplies a gas into the chamber, and the substrate holding means holds the substrate in the chamber. The plasma generating means converts the gas between the shower plate and the substrate holding means into plasma. The shower plate is provided in the chamber so as to face the substrate holding means, and has a function of dispersing the gas from the gas supply means toward the substrate holding means. The shower plate is provided in a region including the mounting position of the substrate, has a flat plate-like main surface portion substantially parallel to the substrate surface, and a cylindrical shape, and one end is connected to an outer peripheral portion of the main surface portion. , And the other end is connected to the chamber. The main surface portion is provided with a plurality of first gas supply holes for blowing out the gas to the substrate holding means side. The side portion is provided with a plurality of second gas supply holes for blowing out the gas toward the side wall of the chamber. The shower plate includes a first space that allows gas to flow to the substrate holding means through the first gas supply hole, and a gas to the sidewall of the chamber through the second gas supply hole. And a partition wall that divides the second space.

FIG. 1 is a cross-sectional view schematically showing an example of the structure of the semiconductor manufacturing apparatus according to the embodiment. FIG. 2 is a cross-sectional view schematically showing another example of a shower plate.

  Exemplary embodiments of a semiconductor manufacturing apparatus and a semiconductor device manufacturing method will be explained below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment.

  FIG. 1 is a cross-sectional view schematically showing an example of the structure of the semiconductor manufacturing apparatus according to the embodiment. Here, a plasma CVD apparatus 10 will be described as an example of a semiconductor manufacturing apparatus. The plasma CVD apparatus 10 has an airtight chamber 11.

  In the chamber 11, there is provided a substrate holder 12 that horizontally supports a wafer (substrate) 100 as a processing target and functions as a lower electrode. Although not shown, a holding mechanism such as an electrostatic chuck mechanism that electrostatically attracts the wafer 100 is provided on the surface of the substrate holding unit 12. The substrate holding unit 12 is grounded.

  A shower plate 13 functioning as an upper electrode is provided above the substrate holding part 12 so as to face the substrate holding part 12 functioning as a lower electrode. Although not shown, a power supply line for supplying high frequency power is connected to the shower plate 13, and a blocking capacitor, a matching unit, and a high frequency power supply are connected to the power supply line. The shower plate 13 is fixed in the vicinity of the upper portion of the chamber 11 at a predetermined distance from the substrate holding unit 12 so as to face the substrate holding unit 12 in parallel. With such a structure, the shower plate 13 and the substrate holding part 12 constitute a pair of parallel plate electrodes.

  The shower plate 13 is provided so as to surround a space near the upper portion of the chamber 11, and has a main surface portion 131 that is substantially parallel to the substrate holding surface of the substrate holding portion 12 provided in a region facing the substrate holding portion 12, and the main surface portion 131. A cylindrical side surface portion 132 provided so as to support the shower plate 13, and a fixing portion 133 that fixes the shower plate 13 with a member near the upper surface of the chamber 11 and a fixing member. The shower plate 13 has, for example, a circular container-like structure in which the area of the opening increases from the lower surface to the upper portion.

  The main surface portion 131 of the shower plate 13 is provided with a plurality of gas supply holes 131a penetrating in the thickness direction of the plate. In the present embodiment, the direction of the holes is also directed to the side surface in the chamber 11 in the side surface portion 132. A gas supply hole 132a is provided. Here, a plurality of gas supply holes 132 a penetrating in the thickness direction of the plate are provided in the side surface portion 132. In addition, a partition wall 134 that separates the gas supplied from the gas supply hole 131 a of the main surface portion 131 and the gas supplied from the gas supply hole 132 a of the side surface portion 132 is constituted by the shower plate 13 and the upper surface of the chamber 11. It is provided in the space. Hereinafter, a space formed by the partition wall 134, the main surface portion 131 of the shower plate 13 and the chamber 11 is referred to as a main gas supply space 135, and is formed by the partition wall 134, the side surface portion 132 of the shower plate 13 and the chamber 11. The space is a sub gas supply space 136.

  In the vicinity of the upper portion of the chamber 11, gas supply ports 14 and 15 for supplying a processing gas used during film formation or cleaning are provided. Here, the main gas supply port 14 is provided near the center of the upper surface of the chamber 11 so as to be connected to the main gas supply space 135, and the shower plate 13 is formed so as to be connected to the sub gas supply space 136. A gas supply port 15 is also provided near the periphery of the position.

In the plasma CVD apparatus 10, a film forming gas supply unit 21 for supplying a film forming gas as a processing gas used for forming a film such as TEOS (Tetraethoxysilane) / He gas or silane into the chamber 11, He, Ar, or the like. An inert gas supply unit 22 that supplies the inert gas and a cleaning gas supply unit 23 that supplies a cleaning gas such as NF ₃ gas are provided.

  The film forming gas supply unit 21 is connected to the gas supply port 14 via pipes 31 and 34. The inert gas supply unit 22 is connected to the gas supply port 14 via pipes 32 and 34, and is connected to the gas supply port 15 via pipes 32 and 35. The cleaning gas supply unit 23 is connected to the gas supply port 14 via pipes 33 and 34, and is connected to the gas supply port 15 via pipes 33 and 35.

  Here, the pipe 35 has a structure branched from the pipes 32 and 33, but the pipe connected from the inert gas supply unit 22 to the gas supply port 14 and the gas supply port 15 from the inert gas supply unit 22. You may make it provide piping connected to this independently. Similarly, for the cleaning gas supply unit 23, a pipe connected from the cleaning gas supply unit 23 to the gas supply port 14 and a pipe connected from the cleaning gas supply unit 23 to the gas supply port 15 are provided independently. Also good.

  The pipes 31 to 33 are provided with gas valves 41 to 43 that can switch on / off the gas flow flowing through the pipes 31 to 33. That is, when the gas valves 41 to 43 are opened, gas flows through the pipes 31 to 33, and when the gas valves 41 to 43 are closed, no gas flows through the pipes 31 to 33. For example, during film formation, the gas valves 41 and 42 are opened and the gas valve 43 is closed, so that the film formation gas flows from the film formation gas supply unit 21 to the gas supply port 14 and the inert gas supply unit 22 supplies gas. An inert gas is allowed to flow through the ports 14 and 15 so that the cleaning gas does not flow into the chamber 11. On the other hand, at the time of cleaning, the gas valves 41 and 42 are closed and the gas valve 43 is opened, so that the film forming gas and the inert gas do not flow into the chamber 11, and the gas supply ports 14 and 15 are supplied from the cleaning gas supply unit 23. The cleaning gas is made to flow to

  The pipes 31, 32, 33, and 35 are provided with gas flow rate control units 51, 52, 53, 54, and 55 that control the flow rate of the gas flowing through the pipes 31, 32, 33, and 35. The gas flow rate control unit 51 controls the flow rate of the deposition gas, the gas flow rate control unit 52 controls the flow rate of the inert gas supplied to the gas supply port 14, and the gas flow rate control unit 53 supplies the gas supply port 14 The flow rate of the cleaning gas is controlled. The gas flow rate control unit 54 controls the flow rate of the inert gas supplied to the gas supply port 15, and the gas flow rate control unit 55 controls the flow rate of the cleaning gas supplied to the gas supply port 15.

  In the main gas supply space 135 enclosed between the main surface portion 131 of the shower plate 13 and the partition wall 134, a dispersion plate 16 that rectifies and distributes the gas supplied from the gas supply port 14 is provided. The dispersion plate 16 has a main surface portion 161 disposed substantially parallel to the main surface portion 131 of the shower plate 13 and a side surface portion 162 that supports the main surface portion 161 from the upper surface of the chamber 11. A plurality of gas supply holes 161a penetrating in the thickness direction are provided.

  The chamber 11 is provided with a gas exhaust port 61, and a vacuum pump 63, which is an exhaust means, is connected to the gas exhaust port 61 through a pipe 62. Thereby, the gas in the chamber 11 is exhausted. The gas exhaust port 61 is provided with a gate valve (not shown) so that the exhaust amount can be adjusted by the opening degree of the gate valve.

  The gas valves 41 to 43, the gas flow rate control units 51 to 55, the high-frequency power supply and the gate valve are controlled according to a program created in advance. A control device (not shown) that controls gas flow rate control and high-frequency power supply is connected.

  Next, an outline of processing in the plasma CVD apparatus 10 configured as described above will be described. In this plasma CVD apparatus 10, the wafer 100 is transported into the chamber 11, placed on the substrate holding unit 12 and subjected to film formation, and then the wafer 100 is unloaded from the chamber 11 and deposited in the chamber 11. A cleaning process is performed to remove the film and by-products. Then, the film forming process is performed again. The cleaning process may be performed every time a film is formed on the wafer 100, that is, each time a film is formed, or after a film is formed on a plurality of wafers 100, that is, after a plurality of film formation processes. Sometimes done later. Below, the film-forming process and cleaning process in the plasma CVD apparatus 10 are demonstrated.

<Film formation process>
First, the wafer 100 is placed on the substrate holding unit 12, and the wafer 100 is fixed on the substrate holding unit 12 by, for example, an electrostatic chuck mechanism (not shown). Next, after the inside of the chamber 11 is brought to a predetermined degree of vacuum by the vacuum pump 63, the gas valves 41 and 42 are opened, and the gas valve 43 is closed. As a result, a film forming gas such as TEOS gas is supplied from the film forming gas supply unit 21 into the chamber 11 through the gas supply port 14, and an inert gas such as He is supplied from the inert gas supply unit 22 as a gas. It is supplied into the chamber 11 from the ports 14 and 15. At this time, the film forming gas is controlled to have a predetermined flow rate by the gas flow rate control unit 51 and supplied to the main gas supply space 135, and the inert gas has a predetermined flow rate by the gas flow rate control unit 52. And is supplied to the main gas supply space 135, and is controlled by the gas flow rate control unit 54 to have a predetermined flow rate and is supplied to the sub gas supply space 136. As a result, a mixed gas of a film forming gas and an inert gas is supplied to the main gas supply space 135, and an inert gas is supplied to the sub gas supply space 136.

  The mixed gas is dispersed in the main gas supply space 135 by passing through the gas supply holes 161 a of the dispersion plate 16, and further from the gas supply holes 131 a provided in the shower plate 13 to the space on the substrate holding unit 12 side. Evenly supplied. At this time, the mixed gas does not move to the auxiliary gas supply space 136 because the partition wall 134 exists.

  Simultaneously with the supply of the mixed gas into the chamber 11, the inert gas supplied into the sub gas supply space 136 is supplied into the chamber 11 through the gas supply hole 132 a. At this time, since the gas supply hole 132a is directed to the side wall of the chamber 11, an inert gas is blown onto the side wall of the chamber 11.

  After that, a high frequency voltage is applied to the shower plate 13 with the substrate holder 12 grounded, and plasma is generated in the space between the shower plate 13 and the substrate holder 12. As a result, the mixed gas is turned into plasma, and a film is formed on the wafer 100. At this time, the inert gas is supplied from the gas supply hole 132 a of the shower plate 13 toward the side wall of the chamber 11, and a film is not easily formed on the side wall of the chamber 11 compared to the wafer 100. Yes.

  After performing the film forming process for a predetermined time, the gas valves 41 and 42 are closed, the inside of the chamber 11 is evacuated, and then the gas valve 42 is opened. Then, the wafer 100 is unloaded from the chamber 11. Thus, the film forming process is completed.

<Cleaning process>
After the inside of the chamber 11 from which the wafer 100 is unloaded is made a predetermined degree of vacuum by the vacuum pump 63, the gas valves 41 and 42 are closed and the gas valve 43 is opened. Accordingly, a cleaning gas such as NF ₃ gas is supplied from the cleaning gas supply unit 23 into the chamber 11 through the gas supply ports 14 and 15. At this time, the cleaning gas is controlled to have a predetermined flow rate by the gas flow rate control unit 53 and is supplied to the main gas supply space 135, and is controlled to have a predetermined flow rate by the gas flow rate control unit 55. It is supplied to the supply space 136. As a result, the cleaning gas is supplied to the main gas supply space 135 and the sub gas supply space 136 at a predetermined flow rate.

  In the main gas supply space 135, the cleaning gas is dispersed by passing through the gas supply holes 161a of the dispersion plate 16, and is further substantially uniform from the gas supply holes 131a provided in the shower plate 13 to the space on the substrate holding unit 12 side. To be supplied. At the same time, the cleaning gas supplied to the sub gas supply space 136 is supplied into the chamber 11 from the gas supply hole 132a. At this time, since the gas supply hole 132a is directed to the side wall of the chamber 11, the cleaning gas is blown to the side wall of the chamber 11.

  After that, a high frequency voltage is applied to the shower plate 13 with the substrate holder 12 grounded, and plasma is generated in the space between the shower plate 13 and the substrate holder 12. As a result, the cleaning gas is turned into plasma, and the coating film and reaction byproducts formed in the chamber 11 are cleaned. The cleaning gas blown from the main surface portion 131 of the shower plate 13 mainly cleans the film and reaction by-products formed on and around the gas supply holes 131a of the shower plate 13 and the substrate holding portion 12. Further, the cleaning gas is directly blown from the gas supply hole 132a of the side surface portion 132 of the shower plate 13 toward the side wall of the chamber 11, so that the coating film and by-products are effectively removed.

  The flow rate of the cleaning gas blown from the main surface portion 131 and the side surface portion 132 of the shower plate 13 can be arbitrarily changed by the respective gas flow rate control units 53 and 55. For example, in a situation where a large amount of coating or reaction by-product is attached to the inner wall of the chamber 11, the gas flow rate is controlled so that the flow rate of the cleaning gas from the side surface portion 132 of the shower plate 13 becomes relatively large. do it.

  After performing the cleaning process for a predetermined time, the gas valve 43 is closed, the gas in the chamber 11 is exhausted for a while by the vacuum pump 63, and the cleaning process is completed. Thereafter, the film forming process described above is performed.

  In FIG. 1, the shape of the shower plate 13 includes a flat plate-like main surface portion 131 and a side surface portion 132 connected at an angle larger than 90 degrees on the outer peripheral portion of the main surface portion 131. The side portion 132 has a structure in which a plurality of gas supply holes 131a and 132a penetrating in the thickness direction of the plate are provided. The gas is directed from the auxiliary gas supply space 136 toward the side wall in the chamber 11. Any other shape may be used as long as it has a gas supply hole 132a through which gas can be blown out. FIG. 2 is a cross-sectional view schematically showing another example of a shower plate. The shape of the shower plate 13 in FIG. 2 includes a flat plate-like main surface portion 131 and a cylindrical side surface portion 132 connected at an angle of 90 degrees on the outer peripheral portion of the main surface portion 131. A plurality of gas supply holes 132 a are provided so that gas can be blown out toward the side wall in the chamber 11. The same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  In this shower plate 13, the gas supply hole 131 a of the main surface portion 131 has a shape penetrating in the thickness direction of the plate, but in the side surface portion 132, the gas supply hole 132 a is inclined at an angle from the thickness direction of the plate. Is provided. The gas supply hole 132 a in the side surface portion 132 is formed at an angle at which the gas hits the side wall in the chamber 11 when the shower plate 13 is attached in the chamber 11.

  In addition, a heater may be provided on the member of the shower plate 13 constituting the auxiliary gas supply space 136. By doing so, the temperature of the gas supplied to the sub gas supply space 136 at the time of cleaning becomes high, and the cleaning effect can be enhanced.

  In the present embodiment, the gas supply provided so that the gas directly hits the shower plate 13 and the main gas supply space 135 having the gas supply holes 131 a for supplying the gas to the processing target and the side wall in the chamber 11. A partition wall 134 for partitioning the auxiliary gas supply space 136 having the hole 132a is provided. During cleaning of the chamber 11, the cleaning gas is caused to flow through both the main gas supply space 135 and the sub gas supply space 136, so that the film and reaction by-products formed on the substrate holding portion 12 and the periphery thereof are removed. In addition to the removal, there is an effect that the coating film and reaction by-product formed on the side wall in the chamber 11 can be efficiently removed. In particular, since the cleaning gas is directly brought into contact with the side wall of the chamber 11 by the structure in which the cleaning gas is blown toward the side wall of the chamber 11, the shower plate 13 having the structure in which the cleaning gas is blown toward the side wall of the chamber 11 is not provided. As compared with a typical plasma CVD apparatus, the cleaning time can be shortened.

  In addition, an inert gas wall is formed in the vicinity of the side wall in the chamber 11 by flowing an inert gas into the auxiliary gas supply space 136 during film formation. As a result, the deposition rate of the coating or reaction by-product on the side wall in the chamber 11 during film formation can be reduced as compared with the periphery of the substrate holder 12. That is, there is an effect that the amount of coating or reaction by-product attached to the side wall in the chamber 11 during film formation can be reduced, and the cleaning time during the cleaning process can be further shortened.

  In the above description, the plasma CVD apparatus 10 has been described as an example, but the same effect can be obtained for a semiconductor manufacturing apparatus such as a dry etching apparatus.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Plasma CVD apparatus, 11 ... Chamber, 12 ... Substrate holding part, 13 ... Shower plate, 14, 15 ... Gas supply port, 16 ... Dispersion plate, 21 ... Deposition gas supply part, 22 ... Inert gas supply part, DESCRIPTION OF SYMBOLS 23 ... Cleaning gas supply part, 31-35, 62 ... Piping, 41-43 ... Gas valve, 51-55 ... Gas flow control part, 61 ... Gas exhaust port, 63 ... Vacuum pump, 100 ... Wafer, 131, 161 ... Main Surface portion, 131a, 132a, 161a ... gas supply hole, 132, 162 ... side surface portion, 133 ... fixing portion, 134 ... partition wall, 135 ... main gas supply space, 136 ... sub gas supply space.

Claims (7)

A chamber;
Gas supply means for supplying gas into the chamber;
Substrate holding means for holding the substrate in the chamber;
A shower plate provided opposite to the substrate holding means in the chamber, and for dispersing the gas from the gas supply means to the substrate holding means side;
Plasma generating means for converting the gas between the shower plate and the substrate holding means into plasma;
In a semiconductor manufacturing apparatus comprising:
The shower plate is
Provided in a region including the mounting position of the substrate, a plate-like main surface portion substantially parallel to the substrate surface;
A side surface having a cylindrical shape, one end connected to the outer peripheral portion of the main surface portion, and the other end connected to the chamber;
Have
The main surface portion is provided with a plurality of first gas supply holes so as to blow out the gas to the substrate holding means side,
The side portion is provided with a plurality of second gas supply holes so as to blow out the gas toward the side wall of the chamber.
The shower plate causes a gas to flow to the side of the chamber through the first gas supply hole and the first space for flowing the gas to the substrate holding means side through the second gas supply hole. A semiconductor manufacturing apparatus comprising: a partition wall that partitions the second space portion. The gas supply means includes a processing gas supply means for supplying a processing gas used when processing the substrate, and a cleaning gas supply means used for cleaning the inside of the chamber. ,
A first pipe connecting between the processing gas supply means and the first space of the chamber;
Second and third pipes for connecting between the cleaning gas supply means and the first and second space portions of the chamber, respectively;
Control means for controlling switching of supply of the processing gas and the cleaning gas to the chamber;
The semiconductor manufacturing apparatus according to claim 1, further comprising:   The semiconductor manufacturing apparatus according to claim 2, further comprising a flow rate control unit that controls a flow rate of the cleaning gas in each of the second pipe and the third pipe. The gas supply means further includes an inert gas supply means for supplying an inert gas,
A fourth pipe for connecting the inert gas supply means and the second space of the chamber;
The control means supplies the processing gas to the first space portion and simultaneously supplies the inert gas to the second space portion and the processing gas supply means and the inert gas. 3. The semiconductor manufacturing apparatus according to claim 2, wherein the gas supply means is controlled. A substrate processing step of processing the substrate by turning it into a plasma while blowing a processing gas in a shower-like manner onto the substrate placed on the substrate holding means in the chamber;
A substrate unloading step of unloading the substrate from the chamber;
A cleaning step of cleaning the inside of the chamber by causing the cleaning gas to be blown out in a shower on the substrate holding means, and at the same time into a plasma while being blown out toward the side wall in the chamber.
A method for manufacturing a semiconductor device, comprising:   In the cleaning step, the flow rate of the cleaning gas to be flowed onto the substrate holding means and the flow rate of the cleaning gas to be flowed toward the side wall in the chamber are controlled to have a predetermined ratio. Item 6. A method for manufacturing a semiconductor device according to Item 5.   7. The semiconductor device according to claim 5, wherein, in the substrate processing step, the processing gas is allowed to flow over the substrate in a shower shape and simultaneously blown out in a shower shape toward a side wall in the chamber. Manufacturing method.

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