KR20020056194A - Apparatus for depositing a single-crystal silicon - Google Patents

Abstract

PURPOSE: An apparatus for depositing single crystalline silicon is provided to improve growth velocity of a single crystalline silicon by reducing thermal budget, and to obtain process stability and the cell efficiency for integration, and to form the structure of cells as a cross shape. CONSTITUTION: An upper and a lower quartz domes(11,12) are on a wafer supporter(17). An upper heater assembly comprises a plurality of halogen lamp(13) and a plurality of ultraviolet lamp(14) in the upper quartz dome. A lower heater assembly comprises a plurality of halogen lamp(13) in the lower quartz. The wafer supporter is connected with a wafer rotation part(18) by which the wafer rotation part can be rotated. A process gas inlet(15) and a process outlet(16) are in a portion of a chamber. A process gas laminar-flows on a wafer(19).

Description

Apparatus for depositing a single-crystal silicon

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for single crystal silicon deposition, in particular a process gas by direct or indirect heating by a plurality of halogen lamps in a single wafer type low pressure chemical vapor deposition (LPCVD) apparatus. It is possible to reduce the heat load generated when depositing single crystal silicon by selective epitaxial growth by activating the process gas to increase the growth rate of single crystal silicon and to secure process stability. It relates to a device for.

In general, low pressure chemical vapor deposition and ultra low pressure chemical vapor deposition are used for the equipment configuration for epitaxial silicon growth and selective silicon growth. Conventional low pressure chemical vapor deposition apparatus is a single wafer type to grow a single crystal silicon film on the wafer by direct or indirect heating method using a halogen lamp, and heating method using a reactor chamber or a high frequency coil (RF coil). There is a multi wafer type method in which a single crystal silicon film is grown on several tens to hundreds of wafers at a time. The low pressure chemical vapor deposition method for single crystal silicon growth obtains a single crystal silicon film by directly or indirectly activating a process gas by a lamp. However, it is difficult to secure the growth rate and process stability of single crystal silicon due to the following problems.

First, the single crystal silicon growth temperature is closely related to the kind of source gas. The growth by the conventional thermal activation method has a certain limit in terms of speed, so that a high temperature process is inevitable, and SiCl ₄ , SiCl ₃ H gas is used as a source gas applied to such a high temperature process. At low temperatures, the process is mainly performed by the highly reactive DCS (SiCl ₂ H ₂ ) or MS (SiH ₄ ) source gas, but the quality of the thin film is deteriorated.

Second, selective epitaxial growth of silicon (SEG) has to vary the source gas addition ratio according to temperature and pressure to improve selectivity between the conductor and the non-conductor. In order to apply selective growth to devices, it is advantageous to increase the growth rate at low temperatures. However, there is a limit to activating the source gas only with heat for selective growth. This is because, at low temperatures, DCS gas or MS gas is used as the silicon source gas, because the lower the temperature, the faster the temperature that can grow while maintaining selectivity drops.

As a result, in the single crystal silicon film formation method using the single wafer type low pressure chemical vapor deposition apparatus, the biggest difficulty point is the thermal budget.

Accordingly, an object of the present invention is to provide a device for single crystal silicon deposition that can lower the heat load generated when depositing single crystal silicon to improve the growth rate of single crystal silicon and ensure process stability.

The apparatus for single crystal silicon deposition according to the present invention for achieving this object is composed of a wafer support for supporting a wafer and connected to the wafer rotating portion, an upper quartz dome and a lower quartz dome, on one side there is a process gas inlet, the process A chamber having a process gas outlet opposite the gas inlet, a plurality of halogen lamps disposed in the lower quartz dome, a plurality of halogen lamps and a plurality of ultraviolet lamps disposed in the upper quartz dome, the plurality of halogen lamps Is arranged in a dual array structure inside and outside the upper quartz dome, and the plurality of ultraviolet lamps are disposed inside the upper quartz dome.

In addition, the apparatus for deposition of single crystal silicon according to the present invention comprises a wafer support for supporting a wafer and connected with a wafer rotating part, an upper quartz dome and a lower quartz dome, and a process gas inlet on one side and an opposite side to the process gas inlet. A chamber having a process gas outlet therein, a plurality of halogen lamps disposed in the lower quartz dome, a plurality of halogen lamps and a plurality of ultraviolet lamps disposed in the upper quartz dome, and the plurality of halogen lamps are the upper quartz The plurality of ultraviolet lamps may be disposed inside and outside of the dome, and the plurality of ultraviolet lamps may be disposed inside and outside of the upper quartz dome toward the process gas inlet.

1A is a schematic diagram of a low pressure chemical vapor deposition apparatus for single crystal silicon deposition according to a first embodiment of the present invention.

FIG. 1B is a top view of the upper heater assembly of FIG. 1A. FIG.

2A is a schematic diagram of a low pressure chemical vapor deposition apparatus for single crystal silicon deposition according to a second embodiment of the present invention.

FIG. 2B is a top view of the upper heater assembly of FIG. 2A. FIG.

<Explanation of symbols for the main parts of the drawings>

11, 21: top quartz dome 12, 22: bottom quartz dome

13, 23: halogen lamp 14, 24: ultraviolet lamp

15, 25: process gas inlet 16, 26: process gas outlet

17, 27: wafer support 18, 28: wafer rotating part

19, 29: wafer

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1A is a schematic diagram of a low pressure chemical vapor deposition apparatus for single crystal silicon deposition according to a first embodiment of the present invention, and FIG. 1B is a plan view of the upper heater assembly of FIG. 1A.

The low pressure chemical vapor deposition apparatus for single crystal silicon deposition according to the first embodiment of the present invention has an upper quartz dome 11 above and a lower quartz dome 11 below the wafer support 17 supporting the wafer 19. There is a lower quartz dome 12. The chamber of the low pressure chemical vapor deposition apparatus is formed by surrounding these quartz domes 11 and 12. The upper quartz dome 11 has an upper heater assembly consisting of a plurality of halogen lamps 13 and a plurality of ultraviolet lamps 14, and the lower quartz dome 12 has a plurality of halogen lamps 13. There is a bottom heater assembly made up. The wafer support 17 is connected to the wafer rotator 18, and by the wafer rotator 18, the wafer support 17 can itself rotate at 10 to 50 RPM (revolutions per minute). One side of the chamber has a process gas inlet (Process gas inlet) 15, the process gas inlet (15) on the opposite side of the process gas inlet (15), the process gas outlet (process gas outlet) (16) There is a laminar flow on the wafer 19.

In the first embodiment of the present invention, the key lies in the construction of an upper heater assembly consisting of a plurality of halogen lamps 13 and a plurality of ultraviolet lamps 14. The plurality of halogen lamps 13 are arranged in a dual array structure inside and outside the upper quartz dome 11, and the plurality of ultraviolet lamps 14 are disposed inside the upper quartz dome 11. That is, only the halogen lamp 13 is disposed outside the upper quartz dome 11, and the halogen lamp 13 and the ultraviolet lamp 14 are disposed together inside the upper quartz dome 11. This arrangement is intended to allow the process gas to be activated most effectively only on the surface of the wafer 19 to eliminate the possibility of unnecessary particle generation. The number or arrangement of the halogen lamps 13 may vary depending on the chamber size. The preferred number or arrangement of the halogen lamps 13 is 55% to 55% of the total halogen lamps 13 of the upper quartz dome 11. It should be 75%, and should be configured so that it can be raised to 1200 ℃. In addition, the halogen lamp 13 disposed inside the upper quartz dome 11 irradiates about 2/3 to the inside of the wafer 19, and the halogen lamp 13 arranged outside the center of the wafer 19 edges. To adjust the angle and position of each of the halogen lamps 13 to irradiate the radial range of the wafer 19.

Hereinafter, a low pressure chemical vapor deposition apparatus for depositing single crystal silicon according to the first embodiment of the present invention will be described in detail.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single wafer type low pressure chemical vapor deposition apparatus for single crystal silicon growth and selective silicon growth, which is highly applicable to semiconductor devices, and is applied to an upper heater assembly among upper and lower heater assemblies including a plurality of halogen lamps 13. A plurality of ultraviolet lamps 14 are inserted.

Where the plurality of ultraviolet lamps 14 are inserted is confined to the upper heater assembly, the upper heater assembly is located outside the upper quartz dome 11 and provides nitrogen cooling to the outside of the upper quartz dome 11. do. The ultraviolet lamp 14 chooses to have a wavelength of 200 to 320 nm, and is based on a mercury base arc lamp. The ultraviolet lamp 14 utilizes carbon dioxide laser, argon ion laser, neodymium-yag laser, excimer laser, and the like by wide focusing. It may be.

The plurality of halogen lamps 13 constituting the upper heater assembly has a double array structure inside and outside the upper quartz dome 11, the number of which must be such that the temperature of the wafer 19 can be raised to 1200 ° C without difficulty. . The number of halogen lamps 13 disposed outside the upper quartz dome 11 is 55% to 75% of the total halogen lamps 13 of the upper quartz dome 11 and is based on the edge of the wafer 19. The direction is adjusted so that the inner and outer sides of the wafer 19 are irradiated half the radius of the wafer 19. The halogen lamp 13 disposed inside the upper quartz dome 11 allows the inside area to be irradiated with a 10% error before and after at 2/3 of the wafer 19.

In the plurality of halogen lamps 13 and the plurality of ultraviolet lamps 14 arranged inside the upper quartz dome 11, each of the ultraviolet lamps 14 is individually disposed between the plurality of halogen lamps 13 arrangements. Such a plurality of ultraviolet lamps 14 are arranged to irradiate the wafer 19 as a whole, the number of which is ± 2 to the number of halogen lamps 13 arranged inside the upper quartz dome 11, It is not arranged continuously.

As described above, in application to a single crystal silicon thin film manufacturing process using the apparatus according to the first embodiment of the present invention having the upper lamp assembly, it is first applied to hydrogen treatment. The application conditions are such that the temperature is set to 700 to 900 占 폚 with the ultraviolet lamp 14 turned on, and the hydrogen flow is about 10 to 150 slm for 1 to 5 minutes. Backed by the DCS + HCl + H ₂ at low temperatures as the process gas, and a temperature of 700~900 ℃, the process proceeds from the process conditions of a pressure of 5~150Torr. At this time, the DCS gas is 0.05 to ₂ slm, the HCl gas is 0 to ₃ slm, the H ₂ gas is 10 to 150 slm, and doping gases such as PH ₃ and B ₂ H ₆ are also in-situ ( in-situ).

FIG. 2A is a schematic diagram of a low pressure chemical vapor deposition apparatus for single crystal silicon deposition according to a second embodiment of the present invention, and FIG. 2B is a plan view of the upper heater assembly of FIG. 2A.

In the low pressure chemical vapor deposition apparatus for single crystal silicon deposition according to the second embodiment of the present invention, an upper quartz dome 21 is disposed on the upper side of the wafer support 27 supporting the wafer 29. There is a lower quartz dome 22. The chamber of the low pressure chemical vapor deposition apparatus is formed by surrounding these quartz domes 21 and 22. The upper quartz dome 21 has an upper heater assembly consisting of a plurality of halogen lamps 23 and a plurality of ultraviolet lamps 24, and the lower quartz dome 22 has a plurality of halogen lamps 23. There is a bottom heater assembly consisting of. The wafer support 27 is connected to the wafer rotator 28, and by the wafer rotator 28, the wafer support 27 can itself rotate at 10 to 50 RPM (revolutions per minute). At one side of the chamber there is a process gas inlet (25) where the process gas enters, and on the opposite side of the process gas inlet 25 is a process gas outlet (26). There is a laminar flow on the wafer 29.

In the second embodiment of the present invention, the key lies in the construction of an upper heater assembly consisting of a plurality of halogen lamps 23 and a plurality of ultraviolet lamps 24. The plurality of halogen lamps 23 are arranged in a dual array structure inside and outside the upper quartz dome 21, and the plurality of ultraviolet lamps 24 are inside and outside the upper quartz dome 21 toward the process gas inlet 25. Is placed on. That is, the plurality of ultraviolet lamps 24 are located on the side of the process gas inlet 25 on one side of the wafer 29 and are individually installed in the space between the plurality of halogen lamps 23. This arrangement has an advantage of intensively activating a portion of the process gas inlet 25 to ensure uniformity for forming single crystal silicon and available variables depending on gas type, temperature, and pressure as a whole. The number or arrangement of the halogen lamps 23 may vary depending on the chamber size, and the preferred number or arrangement of the halogen lamps 23 is 55% to 55% of the total portion of the halogen lamps 23 of the upper quartz dome 21. It should be 75%, and should be configured so that it can be raised to 1200 ℃. In addition, the halogen lamp 23 disposed inside the upper quartz dome 21 irradiates about 2/3 of the inside of the wafer 29, and the halogen lamp 23 disposed outside the center of the wafer 29 is centered. The angle and position of each of the halogen lamps 23 are adjusted to irradiate the radial range of the wafer 29.

Hereinafter, a low pressure chemical vapor deposition apparatus for depositing single crystal silicon according to a second embodiment of the present invention will be described in detail.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single wafer type low pressure chemical vapor deposition apparatus for single crystal silicon growth and selective silicon growth, which is highly applicable to semiconductor devices, and is applied to an upper heater assembly among upper and lower heater assemblies including a plurality of halogen lamps 23. A plurality of ultraviolet lamps 24 are inserted.

Where the plurality of ultraviolet lamps 24 are inserted is confined to the upper heater assembly, which is located outside the upper quartz dome 21 and provides nitrogen cooling to the outside of the upper quartz dome 21. do. The ultraviolet lamp 24 selects the wavelength of 200-320 nm, and is based on a mercury base arc lamp. The ultraviolet lamp 24 is widely used by focusing on a carbon dioxide laser, an argon ion laser, a neodymium-YAG laser, an excimer laser, and the like. It may be.

The plurality of halogen lamps 23 constituting the upper heater assembly have a double array structure inside and outside the upper quartz dome 21, the number of which must be such that the temperature of the wafer 29 can be raised to 1200 ° C without any problem. . The number of halogen lamps 23 arranged outside the upper quartz dome 21 is 55% to 75% of the total halogen lamps 23 of the upper quartz dome 21, and is based on the edge of the wafer 29. The direction is adjusted so that the inner side and outer side of the wafer 29 are irradiated half the radius of the wafer 29. The halogen lamp 23 disposed inside the upper quartz dome 21 allows the inside area to be irradiated with a 10% error before and after at 2/3 of the wafer 29.

Each of the ultraviolet lamps 24 arranged on the process gas inlet 25 side in and out of the upper quartz dome 21 is individually arranged in the form of a zig-zag between a plurality of halogen lamps 23 arrays. . Such a plurality of ultraviolet lamps 24 are arranged to irradiate the wafer 29 to the center, the number of which is ± 2 to the number of the plurality of halogen lamps 23 arranged inside the upper quartz dome 21.

As described above, in application to a single crystal silicon thin film manufacturing process using the apparatus according to the second embodiment of the present invention having the upper lamp assembly, it is first applied to hydrogen treatment. The application conditions are such that the temperature is set to 700 to 900 ° C. with the ultraviolet lamp 24 turned on, and the hydrogen flow is about 10 to 150 slm for 1 to 5 minutes. Backed by the DCS + HCl + H ₂ at low temperatures as the process gas, and a temperature of 700~900 ℃, the process proceeds from the process conditions of a pressure of 5~150Torr. At this time, the DCS gas is 0.05 to ₂ slm, the HCl gas is 0 to ₃ slm, the H ₂ gas is 10 to 150 slm, and doping gases such as PH ₃ and B ₂ H ₆ are also in-situ ( in-situ).

As described above, the present invention basically adds an arc lamp of an ultraviolet wavelength to a halogen lamp assembly while using a process gas activation method by a halogen lamp, as well as to activate the process gas. It involves increasing the selectivity of the conductors and non-conductors required for selective silicon growth to maximize device utility. As a result, the thermal budget, which was the biggest obstacle to the formation of the single crystal silicon film by the low pressure chemical vapor deposition, can be lowered.

Improvements to existing low pressure chemical vapor deposition apparatus, in particular the technical principles of the present invention for selective silicon growth (SEG), are based on a theoretical background on SEG mechanisms. Halogen lamps in conventional devices also emit light of a wavelength close to ultraviolet light to activate the silicon deposition reaction, but the wavelength is not much greater than thermal activation.

The technical principle is briefly described as follows.

First, it relates to the activation of the gas phase reaction by ultraviolet light, the light of the wavelength of 200 ~ 320mm is optically sufficiently filled with silicon source gas such as SiH ₄ , SiCl ₂ H ₂ , SiCl ₃ H, SiCl ₄ , HCl, H _2, etc. It can be activated. The excitation products, such as reticles or silicon multiplexes, have a high electron affinity for electrons or a high probability of ionization to form a fine charge cluster. On these surfaces Cl- groups can be adsorbed, which positively affects the formation of single crystals. These nanoscale reactive particles with these charges not only facilitate the formation of single crystals on the surface, but also act in favor of the SEG process by amplifying selectivity between conductors and non-conductors.

Secondly, the present invention relates to activating a hydrogen reductin reaction, and an ultraviolet lamp can activate hydrogen treatment, which is a step of removing native oxide from the surface of a silicon wafer. This is because activated hydrogen has a high ability to remove natural oxides. Therefore, the hydrogen bake temperature can be lowered to reduce the thermal budget.

Thirdly, the installation of the ultraviolet lamp, the ultraviolet lamp is installed in the upper quartz dome of the chamber of the low pressure chemical vapor deposition apparatus. The type of ultraviolet lamp is based on an arc lamp containing mercury (Hg). As it is a lamp type, it is not only easy to connect but also does not cost much.

As described above, when the ultraviolet lamp is connected to a halogen lamp assembly which is a heater in a conventional single wafer type low pressure chemical vapor deposition apparatus, the following effects can be obtained.

First, the process temperature can be reduced by lowering the hydrogen treatment temperature.

Second, it is possible to secure much faster growth rate of single-crystal silicon compared to the existing process shipbuilding, and to lower the process temperature.

Third, selective silicon growth is highly advantageous in terms of process application because it improves selectivity.

Fourth, the quality of the single crystal silicon thin film can be improved.

Claims (21)

A wafer support that supports the wafer and is connected to the wafer rotator, A chamber comprising an upper quartz dome and a lower quartz dome, having a process gas inlet on one side and a process gas outlet on the opposite side of the process gas inlet; A plurality of halogen lamps disposed in the lower quartz dome, A plurality of halogen lamps and a plurality of ultraviolet lamps disposed in the upper quartz dome; And the plurality of halogen lamps are arranged in a dual array structure inside and outside the upper quartz dome, and the plurality of ultraviolet lamps are disposed inside the upper quartz dome. The method of claim 1, And said ultraviolet lamp has a wavelength of 200-320 nm. The method of claim 1, And said ultraviolet lamp is a mercury base arc lamp. The method of claim 1, The ultraviolet lamp is a device for deposition of single crystal silicon, characterized in that the focusing and utilizing a wide range of carbon dioxide laser, argon ion laser, neodymium-yag laser, excimer laser. The method of claim 1, Wherein the number of halogen lamps disposed outside the upper quartz dome is 55% to 75% of the total halogen lamps of the upper quartz dome. The method of claim 1, And the plurality of halogen lamps disposed outside the upper quartz dome are oriented to irradiate a wafer radius about half the wafer inward and outward relative to the edge of the wafer. The method of claim 1, And the plurality of halogen lamps disposed in the interior of the upper quartz dome are arranged to irradiate the inner area with 10% error before and after at 2/3 of the wafer. The method of claim 1, Wherein in the plurality of halogen lamps and the plurality of ultraviolet lamps disposed within the upper quartz dome, each of the ultraviolet lamps is individually disposed between the plurality of halogen lamp arrangements. The method of claim 1, And said plurality of ultraviolet lamps are arranged to irradiate the wafer as a whole. The method of claim 1, Wherein the number of ultraviolet lamps is ± 2 the number of the plurality of halogen lamps disposed in the interior of the upper quartz dome. The method of claim 1, And said plurality of ultraviolet lamps are not placed next to each other in succession. A wafer support that supports the wafer and is connected to the wafer rotator, A chamber comprising an upper quartz dome and a lower quartz dome, having a process gas inlet on one side and a process gas outlet on the opposite side of the process gas inlet; A plurality of halogen lamps disposed in the lower quartz dome, A plurality of halogen lamps and a plurality of ultraviolet lamps disposed in the upper quartz dome; The plurality of halogen lamps are disposed in a double array structure inside and outside the upper quartz dome, and the plurality of ultraviolet lamps are disposed inside and outside the upper quartz dome toward the process gas inlet. Device for. The method of claim 12, And said ultraviolet lamp has a wavelength of 200-320 nm. The method of claim 12, And said ultraviolet lamp is a mercury base arc lamp. The method of claim 12, The ultraviolet lamp is a device for deposition of single crystal silicon, characterized in that the focusing and utilizing a wide range of carbon dioxide laser, argon ion laser, neodymium-yag laser, excimer laser. The method of claim 12, Wherein the number of halogen lamps disposed outside the upper quartz dome is 55% to 75% of the total halogen lamps of the upper quartz dome. The method of claim 12, And the plurality of halogen lamps disposed outside the upper quartz dome are oriented to irradiate a wafer radius about half the wafer inward and outward relative to the edge of the wafer. The method of claim 12, And the plurality of halogen lamps disposed in the interior of the upper quartz dome are arranged to irradiate the inner area with 10% error before and after at 2/3 of the wafer. The method of claim 12, And each of said ultraviolet lamps disposed in the process gas inlet in and out of said upper quartz dome are individually disposed in a jig-zeg form between said plurality of halogen lamp roles. The method of claim 12, And said plurality of ultraviolet lamps are arranged to irradiate a wafer to the center. The method of claim 12, Wherein the number of ultraviolet lamps is ± 2 the number of the plurality of halogen lamps disposed in the interior of the upper quartz dome.