JP7749484B2 - Film forming apparatus and method for treating the film forming apparatus - Google Patents

Description

This disclosure relates to a film forming apparatus and a processing method for the film forming apparatus.

Patent Document 1 discloses a film formation apparatus that includes a rotary stage that holds a wafer, a susceptor configured to house the rotary stage within its internal space, a gas supply mechanism configured to create a flow of processing gas in the internal space from outside the rotary stage in a direction perpendicular to the central axis, and a container that houses the susceptor.

JP 2016-100462 A

One aspect of the present disclosure provides a film forming apparatus and a method for treating the film forming apparatus that suppresses adhesion of products to wall surfaces.

A film forming apparatus according to one aspect of the present disclosure comprises a carbon cylinder, an induction heating coil for induction heating the carbon cylinder, a holder disposed in the internal space of the carbon cylinder for holding a substrate, a holder rotation drive unit for rotating the holder, and a cylinder rotation drive unit for rotating the carbon cylinder , wherein the rotation axis about which the holder rotates is perpendicular to the rotation axis about which the carbon cylinder rotates .

One aspect of the present disclosure provides a film-forming apparatus and a method for treating the film-forming apparatus that suppresses adhesion of products to wall surfaces.

FIG. 1 is a perspective view illustrating a characteristic configuration of a film forming apparatus according to an embodiment. 1 is a schematic diagram illustrating an example of a characteristic configuration of a film forming apparatus according to an embodiment, as viewed in an axial direction. FIG. 1 is a schematic cross-sectional view of a film forming apparatus according to an embodiment. FIG. 2 is a schematic cross-sectional view showing an example of a film forming apparatus according to an embodiment, in which a part of the film forming apparatus is partially enlarged. 1 is a schematic cross-sectional view of a film formation apparatus in a film formation process. 1 is a schematic cross-sectional view of a film forming apparatus in a cleaning process.

The following describes embodiments of the present disclosure with reference to the drawings. In each drawing, identical components are designated by the same reference numerals, and duplicate descriptions may be omitted.

<Film forming apparatus 1>
An example of a film formation apparatus 1 according to an embodiment will be described with reference to FIGS. 1 to 4. FIG. 1 is an example of a perspective view showing a characteristic configuration of the film formation apparatus 1 according to an embodiment. FIG. 2 is an example of a schematic diagram showing a characteristic configuration of the film formation apparatus 1 according to an embodiment when viewed in the axial direction. FIG. 3 is an example of a schematic cross-sectional view of the film formation apparatus 1 according to an embodiment. FIG. 4 is an example of a schematic cross-sectional view in which a portion indicated by a two-dot chain line A of the film formation apparatus 1 according to an embodiment is enlarged. The film formation apparatus 1 will be described as a thermal CVD (Chemical Vapor Deposition) apparatus that forms a SiC film on a wafer (substrate) W.

The container 10 is made of, for example, stainless steel (SUS) and has a cylindrical shape with a horizontal central axis. A loading/unloading port 11 for loading and unloading wafers W is formed in the sidewall at one axial end of the container 10. The loading/unloading port 11 is opened and closed by a gate valve 12. An exhaust path 13 is provided at the other axial end of the container 10. An exhaust device (not shown) is connected to the exhaust path 13. This allows the pressure inside the container 10 to be adjusted to the desired pressure.

The film forming apparatus 1 is equipped with a processing gas supply unit 14 and a cleaning gas supply unit 15.

The process gas supply unit 14 supplies a process gas into the container 10 (the upper space 101 in the carbon cylinder 21 shown in FIG. 2 ₎ by a side flow method. The process gas is a gas used when forming a SiC film on the wafer W, and may be, for example, a mixed gas _{of H2} , _SiH4 , _C3H8 , _C2H2 , _N2 , HCl, Ar, Ne, He, or the like.

The cleaning gas supply unit 15 supplies cleaning gas by a side flow method into the container 10 (the lower space 102 in the carbon cylinder 21 shown in FIG. 2 ). The cleaning gas is a gas used to clean off products adhering to the inner wall surface of the carbon cylinder 21, and may be, for example, a mixed gas of NF ₃ , ClF ₃ , F ₂ , HF, Cl ₂ , etc.

The film forming apparatus 1 also includes a carbon cylinder 21, a quartz cylinder 22, an induction heating coil 23, and a cylinder rotation drive unit 24. Similar to the container 10, the carbon cylinder 21 has a cylindrical shape with a horizontal central axis 21C. The quartz cylinder 22 is provided radially outside the carbon cylinder 21. The quartz cylinder 22 has a cylindrical shape with a horizontal central axis 21C. The induction heating coil 23 is provided radially outside the quartz cylinder 22. The induction heating coil 23 is connected to a high-frequency power supply (not shown). When high-frequency power from the high-frequency power supply is supplied to the induction heating coil 23, the carbon cylinder 21 is heated by induction heating.

The cylinder rotation drive unit 24 rotates the carbon cylinder 21 and the quartz cylinder 22 around the central axis 21C. The cylinder rotation drive unit 24 includes a support unit 25, a magnetic fluid seal 26, a DD motor 27, a support unit 28, and a magnetic fluid seal 29.

The support portion 25 supports one end of the carbon cylinder 21 and the quartz cylinder 22. The support portion 25 is made of an insulating material having heat insulating properties, such as Al ₂ O ₃ .

The magnetic fluid seal 26 has a rotor 26a, a stator 26b, a magnetic fluid 26c, and a bearing 26d. The rotor 26a is fixed to the support 25. The rotor 26a is rotatably supported by the stator 26b via the bearing 26d. The stator 26b is fixed to the container 10. A magnetic fluid 26c is provided between the rotor 26a and the stator 26b, providing a seal between the rotor 26a and the stator 26b.

The DD (direct drive) motor 27 has a rotor 27a, a stator 27b, and a bearing 27c. The rotor 27a is fixed to the support portion 25 via the rotor 26a of the magnetic fluid seal 26. The rotor 27a is rotatably supported by the stator 27b via the bearing 27c. The stator 27b is fixed to the container 10.

The support part 28 supports the other end of the quartz tube 22. The support part 28 is made of an insulating material having heat insulating properties, such as Al ₂ O _3. As a result, the space between the carbon tube 21 and the quartz tube 22 is open at the other end of the quartz tube 22.

The magnetic fluid seal 29 uses a magnetic material to seal between the rotor and stator, and also supports the support part 28 so that it can rotate freely.

With this configuration, the cylinder rotation drive unit 24 can rotate the rotatably supported carbon cylinder 21 and quartz cylinder 22 as a single unit by driving the DD motor 27.

A seal member 61 is provided between the stator 26b and the vessel 10. A seal member 62 is provided between the rotor 26a and the support portion 25. A seal member 63 is provided between the support portion 25 and the quartz tube 22. This separates the space inside the quartz tube 22, to which the processing gas or cleaning gas is supplied, from the space outside the quartz tube 22, in which the induction heating coil 23 is located. In other words, the induction heating coil 23 is protected from the processing gas and cleaning gas.

The space inside the carbon cylinder 21 is divided into upper and lower sections by a partition plate 41. A holder 31 that holds a wafer W is placed in the upper space inside the carbon cylinder 21. The holder 31 is supported by a holder support part 33 via a holder rotation drive part 32. The holder rotation drive part 32 has the function of rotating the holder 31 using a rotation axis 31C. The rotation axis 31C about which the holder 31 rotates and the rotation axis (central axis 21C) about which the carbon cylinder 21 rotates are arranged so as to be perpendicular to each other.

The partition plate 41 is made of a conductive material such as carbon. The partition plate 41 is also connected to a high-frequency power supply 42. The high-frequency power supply 42 supplies power to the partition plate 41 when generating plasma in the lower space 102 (see Figure 2) inside the carbon cylinder 21.

The film forming apparatus 1 has a magnet 51 and a magnet driving unit 52.

Magnet 51 forms a magnetic field. When generating plasma 100 (see Figure 6), which will be described later, electrons are captured in the magnetic field of magnet 51, allowing the plasma to be maintained with low power. Furthermore, by providing magnet 51, the region in which plasma 100 is generated can be controlled.

The magnet drive unit 52 can insert the magnet 51 into the space between the carbon tube 21 and the quartz tube 22 (see Figure 6, described below), and retract the magnet 51 from the space between the carbon tube 21 and the quartz tube 22 (see Figure 5, described below).

The control unit 60 is, for example, a computer, and includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), an auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or the auxiliary storage device, and controls the operation of the film formation apparatus 1. The control unit 60 may be provided inside or outside the film formation apparatus 1. If the control unit 60 is provided outside the film formation apparatus 1, the control unit 60 can control the film formation apparatus 1 via communication means, such as wired or wireless.

<Film formation process>
Next, an example of the film formation apparatus 1 in the film formation process will be described with reference to Fig. 5. Fig. 5 is an example of a schematic cross-sectional view of the film formation apparatus 1 in the film formation process.

During the film formation process, the inside of the container 10 is evacuated by an exhaust device (not shown) connected to the exhaust path 13, and the pressure is reduced to a predetermined vacuum atmosphere. The holder 31 holds the wafer W. The magnet 51 is also retracted from between the carbon cylinder 21 and the quartz cylinder 22.

The control unit 60 controls the high-frequency power supply (not shown) for heating to supply high-frequency power to the induction heating coil 23. This heats the carbon cylinder 21 by induction heating. Furthermore, the wafer W held by the holder 31 inside the carbon cylinder 21 is heated to a desired temperature (e.g., 1500°C).

The control unit 60 controls the process gas supply unit 14 to supply the process gas into the container 10. This causes a SiC film to be formed on the wafer W. In addition, products adhere to the inner surface of the carbon cylinder 21.

The interior of the carbon cylinder 21 is divided into upper and lower spaces by a partition plate 41, and the process gas supply unit 14 supplies process gas to the upper space where the holder 31 is located. This prevents products from adhering to the inner surface of the carbon cylinder 21 in the lower space within the carbon cylinder 21.

Furthermore, during the film formation process, the control unit 60 controls the cylinder rotation drive unit 24 (DD motor 27) to rotate the carbon cylinder 21 and the quartz cylinder 22. This allows the products adhering to the inner surface of the carbon cylinder 21 to be dispersed circumferentially. It also prevents the products peeling off from the inner surface of the carbon cylinder 21 from adhering to the wafer W.

Note that, although the control unit 60 has been described as rotating the carbon cylinder 21 and the quartz cylinder 22 during the film formation process, this is not limited to this. For example, the carbon cylinder 21 and the quartz cylinder 22 may be configured to rotate intermittently. For example, the carbon cylinder 21 and the quartz cylinder 22 may be configured to rotate a predetermined angle each time the film formation process for the wafer W is completed. Even with this configuration, the products adhering to the inner surface of the carbon cylinder 21 can be dispersed circumferentially. Furthermore, the products peeling off from the inner surface of the carbon cylinder 21 can be prevented from adhering to the wafer W.

Furthermore, during the film formation process, the magnet 51 can be moved away from the carbon cylinder 21 and retracted. This prevents the magnet 51 from being heated by the carbon cylinder 21 and becoming thermally demagnetized.

<Cleaning process>
Next, an example of the film forming apparatus 1 in the cleaning process will be described with reference to Fig. 6. Fig. 6 is an example of a schematic cross-sectional view of the film forming apparatus 1 in the cleaning process.

During the cleaning process, the inside of the container 10 is evacuated by an exhaust device (not shown) connected to the exhaust path 13, and the pressure is reduced to a predetermined vacuum atmosphere. The holder 31 does not hold the wafer W. The magnet 51 is positioned between the carbon cylinder 21 and the quartz cylinder 22.

The control unit 60 controls the cleaning gas supply unit 15 to supply cleaning gas into the container 10. The control unit 60 also controls the high-frequency power supply 42 for plasma generation to supply high-frequency power to the partition plate 41. This generates plasma 100 of the cleaning gas in the lower space within the carbon cylinder 21. The cleaning gas plasma 100 removes by-products adhering to the inner wall surface of the carbon cylinder 21.

The control unit 60 also controls the cylinder rotation drive unit 24 (DD motor 27) to rotate the carbon cylinder 21, thereby cleaning the inner wall surface of the carbon cylinder 21 in the circumferential direction. The control unit 60 also controls the magnet drive unit 52 to move the magnet 51 in the axial direction of the carbon cylinder 21, thereby moving the generation position of the plasma 100 in the axial direction. This allows the entire inner wall surface of the carbon cylinder 21 to be cleaned appropriately.

Note that while the film formation process and cleaning process have been described as examples of the operation of the film formation apparatus 1, this is not limiting. For example, the cleaning process may be performed simultaneously with the film formation process.

The film forming apparatus 1 has been described above, but the present disclosure is not limited to the above embodiment, and various modifications and improvements are possible within the scope of the gist of the present disclosure as set forth in the claims.

W wafer 1 film forming apparatus 10 container 11 loading/unloading port 12 gate valve 13 exhaust path 14 processing gas supply unit 15 cleaning gas supply unit 21 carbon cylinder 21C central shaft 22 quartz cylinder 23 induction heating coil 24 cylinder rotation drive unit 25 support unit 26 magnetic fluid seal 27 DD motor 28 support unit 29 magnetic fluid seal 31 holder 31C rotation shaft 32 holder rotation drive unit 33 holder support unit 41 partition plate 42 high frequency power supply 51 magnet 52 magnet drive unit 60 control unit 100 plasma

Claims (6)

Carbon tube and
an induction heating coil for induction heating the carbon cylinder;
a holder disposed in the internal space of the carbon cylinder and holding a substrate;
a holder rotation drive unit that rotates the holder;
a cylinder rotation drive unit that rotates the carbon cylinder ,
The rotation axis around which the holder rotates and the rotation axis around which the carbon cylinder rotates are perpendicular to each other.
Film deposition equipment. Carbon tube and
an induction heating coil for induction heating the carbon cylinder;
a holder disposed in the internal space of the carbon cylinder and holding a substrate;
a holder rotation drive unit that rotates the holder;
a cylinder rotation drive unit that rotates the carbon cylinder;
a partition plate that divides the internal space of the carbon cylinder ,
Film deposition equipment. Carbon tube and
an induction heating coil for induction heating the carbon cylinder;
a holder disposed in the internal space of the carbon cylinder and holding a substrate;
a holder rotation drive unit that rotates the holder;
a cylinder rotation drive unit that rotates the carbon cylinder;
a magnet disposed on the outer periphery of the carbon cylinder ,
Film deposition equipment. a magnet driving unit that drives the magnet in the axial direction of the carbon cylinder;
The film forming apparatus according to claim 3 . A quartz cylinder is further provided between the carbon cylinder and the induction heating coil.
The film forming apparatus according to any one of claims 1 to 4 . A processing method for a film forming apparatus comprising: a carbon cylinder; an induction heating coil for induction heating the carbon cylinder; a holder disposed in an internal space of the carbon cylinder and for holding a substrate; a holder rotation drive unit for rotating the holder; and a cylinder rotation drive unit for rotating the carbon cylinder, wherein the rotation axis about which the holder rotates is perpendicular to the rotation axis about which the carbon cylinder rotates,
The method for processing a film forming apparatus includes rotating the carbon cylinder when supplying a processing gas into the internal space of the carbon cylinder to perform a film forming process on the substrate.