JPS61196526A - Photochemical vapor deposition process and apparatus thereof - Google Patents

Abstract

PURPOSE:To enable to deposit material films continuously and stably by a method wherein the material films deposited on the inside of a light transmissive member are etch-removed inside a chamber. CONSTITUTION:During the depositing process of amorphous silicon films, the amorphous silicon films are deposited on the inside of a light transmissive window 16 of a a reaction chamber 13 and when photoenergy required for reaction from a low pressure mercury lamp 19 is unde-supplied, a carrie sheet 23 is retreated to isolate a specimen 27 from the reaction chamber 13. Successively polysilane gas in the reaction chamber 13 is satisfactorily substituted with inert gas such as N2 gas etc. to be fed from an etching gas feeding pipe 18 to the reaction chamber 13 for etch-removing any amorphous silicon films deposited on the inside of the light transmissive window 16 using any radicalized gas. Through these procedures, the amorphous silicon films may be deposited continuously on a specimen in the reaction chamber without exposing the specimen in process to atmosphere at all.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a photochemical vapor deposition method and apparatus thereof, which are capable of continuously depositing a specific material film without exposing a sample to the outside air.

[Technical background of the invention and its problems]

Recently, in the fields of solar cells and semiconductors, photochemical vapor deposition methods that can form films without damaging samples have been attracting attention. In order to perform such photochemical vapor phase growth stably and continuously, it is necessary to stably and continuously irradiate light energy to excite or decompose the deposition source gas introduced into the reaction chamber or reaction system of the chamber. It is essential.

By the way, as a conventional photochemical vapor phase growth apparatus, one having the structure shown in FIG. 5 is known. That is, 1 in the figure is a chamber with an open top surface, and a light transmitting window 2 made of quartz glass or the like is fixed to the open top of the chamber 1. Above this light transmission window 2, for example, a low pressure mercury lamp 3 is provided which irradiates light into the chamber 1 through the window 2.
'Fi! It is placed. Further, an introduction pipe 4 for introducing raw material gas is connected to the side wall of the chamber 1,
An exhaust pipe 5 is connected to the side wall opposite to the introduction pipe 4. A sample stage 6 is fixed within the chamber 1 . To perform film deposition using such equipment, first,
After setting the sample 7 on the sample stage 6 and introducing raw material gas into the chamber 1 from the introduction pipe 4 and exhausting the air from the exhaust pipe 5 to achieve a predetermined degree of vacuum in the chamber 1, the low-pressure mercury lamp 3 Light is irradiated into the chamber 1 through the light transmission window 2 to excite the introduced gas and deposit a predetermined material film on the sample 7. However, in such film deposition, a material film is also deposited on the inner surface of the light transmitting window 2, so that the light transmitting window 2 loses its initial transparency, resulting in a decrease in the light energy required for gas excitation. In particular, if the deposited material film reduces the transmittance of the light used, the reduction in light energy becomes more significant. For example, when depositing an amorphous silicon film on a sample using S i H4 as a source gas with the help of mercury vapor, or when depositing a 3i3N+ film using SiH+ and N'H3. Therefore, in conventional photochemical vapor deposition equipment,
The film can be deposited only within a time period in which the material film deposited on the inner surface of the light transmitting window 2 does not reduce the light energy. However, if a material film of the desired thickness cannot be deposited within that time, it is necessary to replace or clean the light transmission window 2,
There is a problem that the stability and continuity of film deposition are inhibited.

Note that although the device shown in Figure 4 shows a case in which a lamp is placed outside and light is irradiated into the chamber through a light-transmitting window, a material film may be formed on the tube wall of the lamp even if the lamp is placed inside the chamber. This buildup creates problems similar to those described above.

Attempts to solve the above problems include, for example: (1) a method of purging the inner surface of the light-transmitting window with an inert gas (N2, Ar, etc.) to prevent the deposition of a material film on the inner surface of the light-transmitting window; A method of applying or coating a low-pressure substance with low hydrophilicity (for example, Vonprin Y-25, manufactured by Montecatin Engine Co., Ltd.) on the inner surface to achieve the same effect as in (1) above, (2) A method of applying a light-transparent film Installed near the light-transmitting window,
A method for preventing deposition of a substance film on a light-transmitting window while moving the film, (1) generating light in a chamber;
There is a method of depositing a material film without providing a light transmission window on the optical path. However, all of these methods have drawbacks and have not been put to practical use. For example, in method (2) above, it is difficult to control the pressure inside the chamber and make the film thickness non-uniform due to the entrainment of the source gas by the inert gas, and it is difficult to completely avoid the deposition of the material film on the light-transmitting window. There are problems such as not being able to do it. In the method (2) above, a problem arises in that the coating material contaminates the I film. The above-mentioned method (2) makes it difficult to implement equipment and makes maintenance complicated. In the method (2) above, there is a concern that the sample may be damaged by high-energy particles from the internal light source.

[Purpose of the invention]

The present invention provides a photochemical vapor deposition method that enables stable and continuous deposition of a material film by etching and removing the material film deposited on the inner surface of a light-transmitting member in a chamber. ! It is intended to provide an i-location.

[Summary of the invention]

In the invention of Application No. 1, a material gas to be deposited is introduced into a chamber, and light is irradiated into the chamber through a light transmitting member to excite the gas and form a predetermined material film on a sample placed in the chamber. and a step of etching away the material film on the light transmitting member in a state where etching radicals do not reach the sample on which the material film has been deposited. be. Here, etching the material film on the light-transmitting member without the etching radicals reaching the sample on which the material film has been deposited means etching the material film on the light-transmitting member with the sample separated by a distance greater than the diffusion distance of the etching radicals. etching,
Separate the sample from etching radicals with a partition wall, etc. 1llllt
This means that the material film on the light transmitting member is etched in this state.

The invention of Application N2 provides a chamber having at least two or more chambers, a light transmitting member provided on a wall of the chamber corresponding to at least one of these chambers, and this light transmitting member provided. An etching gas introduction pipe inserted into the chamber in which the material gas to be deposited is inserted, an etching gas introduction pipe inserted into the chamber in which the light transmission member is provided, and an etching gas introduction pipe arranged outside the chamber in correspondence with the light transmission member, a light source for irradiating light to excite the raw material gas introduced into the room from the gas introduction pipe; and a light source disposed corresponding to the light transmitting member q, for radicalizing the gas introduced into the room from the etching gas introduction pipe. radical generating means for supplying the radicals to the vicinity of the light transmitting member; and transport means for transporting the sample into the chamber in which the light transmitting member is provided and transporting the same sample to another chamber during etching in the chamber. This is a photochemical vapor growth apparatus characterized by comprising the following.

A third invention of the present application provides a chamber having at least two or more chambers, a light transmitting window provided in a wall of the chamber corresponding to a first chamber in which an empty sample is placed, and a light transmitting window adjacent to the window. a light transmitting member including a light transmitting protective cover movable to a second chamber adjacent to the first chamber; a deposition material gas introduction pipe inserted into the first chamber; a light source disposed outside the chamber corresponding to the light transmission window and irradiating light for exciting the raw material gas introduced into the first chamber from the raw material gas introducing pipe; , a radical generating means disposed corresponding to the second chamber to radicalize the gas introduced into the second chamber from the etching gas introduction pipe, and transporting the light transmitting protective cover to the first chamber. A photochemical vapor deposition apparatus characterized in that it comprises: a conveying means for conveying the protective cover to the second chamber after the substance film is deposited in the first chamber.

According to the method of the first invention described above, by etching away the material film deposited on the inner surface of the light transmitting member within the chamber, it is possible to perform stable and continuous deposition of the material film. Further, according to the second and third inventions of the present application described above, by etching and removing the material film deposited on the inner surface of the light transmitting member within the chamber, it is possible to perform stable and continuous deposition of the material film. The device can be realized.

[Embodiments of the invention]

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

Example 1 Example 1 will be described with reference to the photochemical vapor deposition apparatus shown in FIGS. 1(a) and 1(b). Note that FIG. 1(a) is a cross-sectional view showing the vapor phase growth process, and FIG. 1(b) is a cross-sectional view showing the etching process.

11 in the figure is a chamber, and the chamber 11 is formed with a reaction chamber 13 separated by a partition wall 12 and a samurai *yi4. A transport port 15 is opened in the gap 112 through which a transport plate, etc., which will be described later, enters and exits. A light transmitting window 16 made of, for example, quartz glass as a light transmitting member is attached to the lower wall surface of the chamber 11 corresponding to the reaction v13. Furthermore, a deposition material gas introduction pipe 17 and an etching gas introduction pipe 18 are inserted into the reaction W13, respectively. A low-pressure mercury lamp 19 serving as a light source, for example, is placed near the outside of the light transmitting window 16 at a predetermined distance from the light transmitting window 16 . The reaction chamber 13
A heating lamp 20 is placed near the upper wall surface of the chamber 11 corresponding to the chamber 11 at a predetermined distance from the wall surface. A pair of flat plate electrodes 21a and 21b, which constitute a part of the radical generating means, are arranged in parallel to each other on the outside of each of the lamps 19, 20. These flat electrodes 21'a
, one of 21b! The pole (for example, 21b) is grounded via the high frequency power source 22, and the other electrode 21a
is grounded. Furthermore, 23 in the figure is the reaction chamber 13.
This is a bush-type transport plate (or transport rod) that transports the sample into the reaction chamber 13 and also transports the sample to the waiting chamber 14 during etching in the reaction chamber 13. A sample stage 24 is attached to the lower surface of the transport plate 23 near its tip. The conveyance plate 23
In the middle of the process, the first shutter 25! However, a second shutter 252 is fitted to each tip. This first shutter 251 closes the transfer port 15 of the partition wall 12 when the sample fixed on the sample stage 24 by the transfer plate 23 is transferred to the reaction chamber 13 as shown in FIG. 1(a). The second shutter 252 closes the shutter 112 when the sample fixed on the sample table 24 is transferred to the waiting room 14 by the transfer plate 23, as shown in FIG.
It functions to close the conveyance port 15 of. Each of the above v
Exhaust pipes 261 and 262 are connected to the upper wall surfaces of the chamber 11 corresponding to 13 and 14, respectively.

Next, a photochemical vapor phase growth method for an amorphous silicon film will be described using the apparatus shown in FIGS. 1(a) and 1(b).

(I) First, after fixing the sample 27 on the sample stage 24 of the transport plate 23, the transport plate 23 is moved forward and the sample 27 on the sample stage 24 is fixed.
7 to the reaction chamber 13, and the first shutter 25
1 closes the conveyance port 15 of the partition wall 12. Subsequently, 5i2Hs and 5i3Hs are introduced from the deposition source gas inlet pipe 17.
A high-order silane gas such as Ultraviolet rays are irradiated from the lamp 19 into the reaction chamber 13 through the light transmission window 16 (Fig. 1(a)).
(Illustrated). At this time, an amorphous silicon film is deposited on the sample 27 by photochemical vapor deposition in which the high-order silane introduced into the reaction chamber 13 is excited and decomposed by ultraviolet rays.

(I) Next, in the amorphous silicon film deposition step, an amorphous silicon film is deposited on the inner surface of the light-transmitting window 16 of the reaction chamber 13, and the initial transparency of the window 16 is lost and the reaction from the low-pressure mercury lamp 19 is prevented. When the required light energy decreases, the supply of high-order silane gas from the deposition material gas introduction tube 17 is stopped, and each lamp 19.
Turn off the power of 20. Next, the transport plate 23 is moved backward to transport the sample 27 on the sample stage 24 to the waiting chamber 14, isolating the sample 27 from the reaction chamber 13, and at the same time
The conveyance port 15 of the partition wall 12 is closed by the shutter 252 . Subsequently, after sufficiently replacing the high-order silane gas in the reaction chamber 13 with an inert gas such as N2 gas, a mixed gas of, for example, CF4 and 02 is supplied into the reaction chamber 13 from the etching gas introduction pipe 18, and the high-frequency power source 22 is turned on to generate plasma in the reaction chamber 13 between the pair of flat plate N electrodes 21a and 21b to radicalize the mixed gas, and the amorphous silicon film deposited on the inner surface of the light transmission window 16 is etched away by the radicalized gas. (as shown in figure (b)).

Next, an amorphous silicon film is deposited on the sample 27 by the same process as in (I) above, and if the transparency of the inner surface of the light-transmitting window 16 of the reaction chamber 13 is lost due to the deposited amorphous silicon film, the above (II) is performed. By repeating the process of etching and removing the amorphous silicon film on the inner surface of the light transmitting window 16, a predetermined II film is etched on the sample 27.
Deposit a thick amorphous silicon film.

According to the method of the present invention, the initial deposition rate of the amorphous silicon film on the sample 27 when the low-pressure mercury lamp 19 is turned on is as follows: , 16cc/n+i
When supplied from the outlet of n, the deposition rate is 3°8 7 mtn, and after 1 hour after turning on the lamp 19, the deposition rate is extremely reduced to 0.1 7 mtn or less.
In the step of etching the amorphous silicon film on the inner surface of the light transmission window 16 with the sample 27 isolated from the reaction chamber 13 in step n), the amorphous silicon film already deposited on the sample 27 is not etched. The transparency of the light transmission window 16 can be restored to its original state, and the low pressure mercury lamp 19
The initial deposition rate can be almost recovered. Therefore, if amorphous silicon accumulates on the inner surface of the light-transmitting window and its transparency is lost, and the light energy required for the reaction with ultraviolet rays from the low-pressure mercury lamp decreases, it is necessary to replace the light-transmitting window or remove the light from the chamber. Operation to take out the window and clean it.

Furthermore, an amorphous silicon film of a predetermined thickness can be continuously deposited on a sample in the chamber without exposing the sample during the process of depositing the amorphous silicon film to the atmosphere. As a result, a homogeneous, uniform, and highly pure amorphous silicon film can be efficiently formed on the sample.

On the other hand, according to the apparatus shown in FIG. 1, a homogeneous, uniform, and highly pure amorphous silicon film can be efficiently formed on a sample as described above. Furthermore, by using the reaction chamber 13 as an etching chamber, the silicon film on the inner surface of the reaction chamber 13 can be etched and removed at the same time when the silicon film on the inner surface of the light transmission window 16 is etched. It is possible to avoid problems such as the silicon peeling off from the inner surface of the sample 27 and the silicon pieces adhering to the sample 27 due to the flow of gas from the source gas introduction pipe 17 and deteriorating the film quality. Further, as shown in FIG. 1, shutters 251 and 252 are provided on the transfer plate 23 to close the transfer port 15 of the partition wall 12 during photochemical vapor deposition and etching so that the reaction chamber is always closed. 13 and waiting room 14
If the structure is such that the source gas flows from the reaction chamber 13 to the standby chamber 14 during deposition of the amorphous silicon film and deposits of silicon canopy occur on the inner surface of the standby chamber 14, or the etching gas flows into the reaction chamber 13 during etching, It is possible to prevent the inconvenience that the amorphous silicon film flowing from the sample 27 to the waiting chamber 14 and etching progresses on the amorphous silicon film already deposited on the sample 27.

In Example 1, the chamber adjacent to the reaction chamber 13 was used as the waiting chamber 14 to avoid etching of the amorphous silicon film on the sample in the etching process.
By providing the standby chamber 14 with the same function as the reaction chamber 13, after the sample is transported to the chamber by a transfer plate, an amorphous film is placed on the sample in the same chamber during the etching process of the light transmission window 16 in the reaction chamber 13. A silicon film may also be deposited. That is, the deposition efficiency of the amorphous silicon film may be improved by using an apparatus having a structure having two reaction chambers.

Example 2 Example 2 will be described with reference to the photochemical vapor deposition apparatus shown in FIGS. 2(a) and 2(b). Note that FIG. 2(a) is a cross-sectional view showing the vapor phase growth process, and FIG. 2(b) is a cross-sectional view showing the etching process.

31 in the figure is a chamber, and the chamber 31 is formed with a reaction chamber 33 and an etching chamber 34, which are partitioned by a partition wall 32. A transport port 35 is opened in the partition wall 32 through which a transport plate, etc., which will be described later, enters and exits. The reaction chamber 33
A light transmitting window 36 made of, for example, quartz glass and constituting one of the light transmitting members is attached to the lower wall surface of the chamber 31 corresponding to the above. Further, a deposition source gas introduction pipe 37 is inserted into the reaction chamber 33 . A low-pressure mercury lamp 38 serving as a light source, for example, is arranged near the outside of the light transmission window 16 at a predetermined distance from the light transmission window 36 . A heating lamp 39 is arranged near the upper wall surface of the chamber 31 corresponding to the reaction chamber 33 at a predetermined distance from the wall surface. The reaction chamber 33
A sample stage 40 is arranged inside and out so that it can be freely taken out and taken out.

In the etching chamber 34, an etching gas introduction pipe 4 is provided.
1 is inserted. Further, a pair of flat plate electrodes 42a and 42b forming a part of radical generating means are arranged in parallel to each other on the upper and lower outer sides of the etching chamber 34. One electrode of these flat electrodes 42a, 42b (for example, 42
b) is grounded via the high frequency power source 43, and the other electrode 42El is grounded. Furthermore, 4 in the figure
Reference numeral 4 denotes a transport plate having a sheet-shaped light transmitting protective cover 45 made of quartz glass, for example, which constitutes the other light transmitting member attached to its tip, and the transport plate 44 carries the protective cover 45 into the reaction chamber 33. The protective cover 45 placed in the reaction chamber 33 is transported close to above the light transmitting window 36, and when the transparency of the upper surface of the protective cover 45 is lost, the protective cover 45 is transferred to the etching chamber 3.
4. Further, a shutter 46 is fitted in the middle of the conveyance plate 44. This shutter 46 serves to close the transport port 35 of the partition wall 32 when the protective cover 45 is transported to the reaction chamber 33 by the transport plate 44, as shown in FIG. 2(a). Exhaust pipes 471 and 472 are connected to the upper wall surfaces of the chamber 31 corresponding to the winter solstice 33 and 34, respectively.

Next, a photochemical vapor phase growth method for an amorphous silicon film will be described using the apparatus shown in FIGS. 2(a) and 2(b).

(I) First, the sample 48 is fixed on the sample stage 40, and the sample stage 40 is transported into the reaction chamber 33, and then the transport plate 44 is advanced and the sheet-like light transmission protection cover 45 at the tip thereof is moved into the reaction chamber. disposed close to and above the light transmission window 36 in 33,
The conveyance port 35 of the partition wall 32 is closed by the shutter 46 . Next, high-order silane gas is introduced into the reaction chamber 33 from the deposition material gas introduction pipe 37, and the gas in the reaction chamber 33 is exhausted through the exhaust pipe 471 to achieve a predetermined degree of vacuum. 48 is heated, and then ultraviolet rays are irradiated from the low-pressure mercury lamp 38 into the reaction chamber 33 through the light-transmitting window 36 and the light-transmitting protective cover 45 (see FIG. 2).
a) As shown). At this time, an amorphous silicon film is deposited on the sample 48 by photochemical vapor deposition in which the ^-order silane introduced into the reaction chamber 33 is excited and decomposed by ultraviolet rays.

(II) Next, in the amorphous silicon film bulk deposition step, an amorphous silicon film is deposited on the surface of the light-transmitting protective cover 45 of the reaction chamber 33, and the initial transparency of the window 16 is lost, causing light leakage from the low-pressure mercury lamp 38. When the light energy required for the reaction decreases, the deposition material gas introduction pipe 37
The supply of high-order silane gas from the lamp 38 and 39 is stopped, and the power to each lamp 38 and 39 is turned off. Continuing, the conveyance plate 44
is moved backward, and the light transmitting protective cover 45 at the tip thereof is transported to the etching chamber 34. Continuously, a mixed gas of CF4 and 02, for example, is supplied into the etching chamber 34 from the etching gas introduction pipe 41, and after making the inside of the etching chamber 34 a predetermined degree of vacuum through the exhaust pipe 472, the high frequency power supply 43 is turned on to Plasma is generated in the etching chamber 34 between the flat plate electrodes 42a and 42t) to radicalize the mixed gas, and the radicalized gas causes the amorphous silicon film deposited on the surface of the light transmission protection cover 45 to be removed from the reaction chamber 33.
The sample 48 is removed by etching in an isolated state (as shown in FIG. 4(b)). At this time, an inert gas such as Ar is supplied from the raw material gas introduction pipe 37 instead of the raw material gas, and the radical gas in the etching chamber 34 flows into the reaction v33 where the sample 48 is placed through the transfer port 35. It is desirable to prevent

Next, the light transmitting protective cover 45 with the amorphous silicon film etched on the surface is transferred to the above (I) by the transport plate 44.
Similar to the process of , the amorphous silicon film is placed close to above the light transmitting window 36, an amorphous silicon film is deposited on the sample 48, and the reaction chamber 3
If the transparency of the surface of the light transmitting protective cover 45 in No. 3 is lost due to the deposited amorphous silicon film, the above (II)
Similar to the process described above, the process of moving the protective cover 45 into the etching chamber 34 using the transport plate 44 and etching away the amorphous silicon film on its surface is repeated to deposit an amorphous silicon film of a predetermined thickness on the sample 48. .

According to the method of the present invention, when the low-pressure mercury lamp 38 is turned on, the initial deposition rate of the amorphous silicon film on the sample 4B is 3.5% under the same conditions as in Example 1.
8 persons/min, and after 11 minutes have elapsed since the lamp 38 was turned on, the deposition rate is extremely reduced to 0.1 persons/min or less, but in the step (I()), the reaction chamber 33 The amorphous silicon film on the surface of the light transmission protection cover 45 is etched in a separate etching chamber 34, that is, the amorphous silicon film is etched while the sample 48 is isolated from etching radicals. The transparency of the light-transmitting protective cover 45 can be restored to its original state without etching the amorphous silicon film, and the initial deposition rate by the low-pressure mercury lamp 38 can be almost restored. If it accumulates and loses its transparency, and the light energy required for the reaction with ultraviolet light from the low-pressure mercury lamp decreases, the conventional operation of replacing the light-transmitting window or removing it from the chamber and cleaning it is necessary. An amorphous silicon film of a predetermined thickness can be continuously deposited on a sample in a chamber without exposing the sample during the process of depositing the amorphous silicon film to the atmosphere.As a result, a homogeneous and uniform layer is formed on the sample. A high-purity amorphous silicon film can be formed efficiently.

On the other hand, according to the apparatus shown in FIG. 2, a homogeneous, uniform, and highly pure amorphous silicon film can be efficiently formed on a sample as described above. Furthermore, by providing an etching chamber 34 separate from the reaction chamber 33, when the amorphous silicon film on the surface of the light transmission protection cover 45 is etched away, the raw material gas in the reaction chamber can be removed as in the apparatus of the first embodiment described above. The operation of replacing with active N2 gas or the like can be omitted. Furthermore, the sheet-like light-transmitting protective cover 45 can be used continuously, rather than moving a disposable film close to the light-transmitting window as in the conventional case, so it is not necessary to move a disposable film close to the light-transmitting window. It can be formed of glass or the like, and it is possible to improve the film deposition rate.

In the apparatus of the second embodiment, the light transmitting protective cover 45 is disposed in either the reaction chamber 33 or the etching chamber 34, but the present invention is not limited thereto.

For example, by using two transport plates with light-transmitting protective covers attached, one light-transmitting protective cover is placed close to the light-transmitting window of the reaction chamber, and the other light-transmitting protective cover is placed in the etching chamber. A structure may be adopted in which, while a material film such as an amorphous silicon film is vapor-phase grown on the sample in the reaction chamber, the other light transmitting protective cover on which the material film is deposited is etched in the etching chamber.

In the apparatus of the second embodiment, one etching chamber 34 is arranged adjacent to the reaction chamber 33, but the structure is not limited thereto. For example, two etching chambers are arranged adjacent to the reaction chamber with partition walls on the left and right, and an etching sludge introduction tube and a pair of flat plate electrodes as radical generating means are arranged in each etching chamber. A light transmitting protective cover arranged corresponding to the reaction chamber and one etching chamber is attached to the plate, and when a material film is deposited on the sample in the reaction chamber, the surface of the light transmitting protective cover is placed in one or the other etching chamber. A structure may also be used in which a material film deposited on the substrate is removed by etching. If such a device is used, while the material film on the surface of one light transmitting protective cover is being etched away in one etching chamber, the material film on the surface of the other light transmitting protective cover is being etched away on the sample in the reaction chamber where the other light transmitting protective cover is placed. This has the advantage that a material film can be deposited more efficiently on a sample.

Example 3 Example 3 will be described with reference to a photochemical vapor deposition apparatus shown in FIG.

51 in the figure is a chamber, and the chamber 51 has a reaction chamber 53 and an etching chamber 54 separated by an L-shaped partition wall 52.
is formed. The partition wall 52 has a slit 55 into which a disk-shaped light transmitting protective cover, which will be described later, is inserted. A light transmitting window 56 made of, for example, quartz glass and constituting one of the light transmitting members is attached to the upper wall surface of the chamber 51 corresponding to the reaction chamber 53. Furthermore, a deposition material gas introduction pipe 57 is inserted into the reaction chamber 53 . For example, an ArF excimer laser oscillator (not shown) is provided outside the light transmission window 56 as a light source.
is located. Inside the reaction chamber 53, there is a sample stage 58.
is fixed, and the sample stage 58 has a built-in heater (not shown).

In the etching chamber 54, an etching gas introduction pipe 5 is provided.
9 is inserted through the reaction chamber 53. Further, in a region extending between the upper part of the reaction chamber 53 and the etching chamber 54, a disk-shaped light transmitting protective cover 60 made of, for example, quartz glass is arranged, which rotates through the slit 55. This protective cover 60 is arranged substantially parallel to the surface of the sample stage 58, and is arranged so that an area slightly smaller than half of the area thereof is located in the reaction chamber 53. Further, a rotary shaft 61 constituting a part of the conveyance means is attached to the center of the disc-shaped light transmitting protection cover 60 located in the etching chamber 54 . A motor (not shown) is connected to this rotating shaft 61. Inside the etching chamber 54, a pair of flat plate electrodes 62a and 62b constituting a part of the radical generating means are arranged parallel to each other so as to sandwich the disc-shaped light transmitting protection cover 60 therebetween.

One electrode of these flat electrodes 62a, 62b (for example, 6
2b) is grounded via a high frequency power source (not shown), and the other electrode 62a is grounded. Furthermore, exhaust pipes 631 and 632 are connected to the upper wall surface of the chamber 51 corresponding to each of the chambers 53 and 54, respectively.

Next, a photochemical vapor phase growth method for an amorphous silicon film will be explained using the apparatus shown in FIG. 3 described above. □ (I) First, the sample 64 is fixed on the sample stage 58, and after heating the sample 64 to a predetermined temperature by a heater (not shown) built into the sample stage 58, a high-order silane gas is reacted from the deposition material gas introduction pipe 57. At the same time as introducing into the chamber 53, the exhaust pipe 63
1, the gas in the reaction chamber 53 is exhausted to a predetermined degree of vacuum. Subsequently, a laser beam 65 is irradiated into the reaction chamber 53 from an ArF excimer laser oscillator (not shown) through the light transmission window 56 and the disk-shaped light transmission protection cover 60. At this time, the high-order silane introduced into the reaction chamber 53 is exposed to the laser beam 6.
An amorphous silicon film is deposited on the sample 64 by photochemical vapor phase growth excited and decomposed by 5.

(If) Next, in the amorphous silicon film deposition step, the reaction chamber 53 of the disc-shaped light transmission protection cover 60 is
When an amorphous silicon film is deposited on the surface of a substantially semicircular area located at , the transparency of the portion of the light transmitting protective cover 60 facing the light transmitting window 56 is lost, and the light energy required for reaction from the laser beam 65 is reduced. The supply of high-order silane gas from the deposition material gas introduction pipe 57 is stopped, the laser oscillator is turned off, and the gas in the reaction chamber 53 is replaced with an inert gas such as N2. Subsequently, the rotating shaft 61 is driven by a motor (not shown) to rotate the light transmitting protective cover 60 by 180 degrees to position the region of the light transmitting protective cover 60 on which the amorphous silicon film is deposited in the etching chamber 54. , the region where the amorphous silicon film is not deposited is opposed to the light transmission window 56. Continuously, a mixed gas of CF4 and 02, for example, is supplied into the etching chamber 54 from the etching gas introduction pipe 59, and the exhaust pipe 632
After setting the inside of the etching chamber 54 to a predetermined degree of vacuum, a high frequency N source (not shown) is turned on and the pair of flat electrodes 62a,
Plasma is generated in the etching chamber 54 between the etching chambers 52 and 62t) to radicalize the mixed gas, and the amorphous silicon film deposited on the surface of approximately half of the light transmitting protective cover 60 is removed from the sample in the reaction chamber 53 by the radicalized gas. It is removed by etching while isolated from 64. At this time, by supplying an inert gas such as Ar instead of the raw material gas from the raw material gas inlet pipe 37, etching can be carried out! ! ! It is desirable to prevent the radicalized gas in 54 from flowing through slit 55 into reaction chamber 53 in which sample 64 is placed.

Next, in the same manner as in step (I) above, a laser beam is irradiated into the reaction chamber 53 through the light transmission window 56 and the disc-shaped light transmission protection cover 60 on which no amorphous silicon film is deposited, and an amorphous silicon film is deposited on the sample 64. When a silicon film is deposited and the transparency of the surface of the area of the light transmission protection cover 60 located in the reaction chamber 53 is lost due to the deposited amorphous silicon film, the etching chamber 5 is removed as in the step (Ilr) above.
The process of etching and removing the amorphous silicon film deposited on approximately half the surface of the disk-shaped light transmitting protective cover 60 in the sample 64 is repeated to deposit an amorphous silicon film of a predetermined thickness on the sample 64.

According to the method of Example 3, the initial deposition rate of the amorphous silicon film on the sample 64 when the laser oscillator is turned on is as follows: , when disilane (S12Hs) is used as the higher-order silane, 600
Although the deposition rate is extremely low to 10 persons/min or less after 2 minutes have passed after turning on the FJR shaker, the disk-shaped light transmitting protective cover 60 is removed in the step (II) above. By rotating the protective cover 60 by 180'' and making the region of the protective cover 60 on which the amorphous silicon film is not deposited face the light transmitting window 56, the initial deposition rate by the laser beam can be recovered. Such a disc-shaped light transmitting protective cover 60 After the rotation, the amorphous silicon film on the surface of approximately half of the light transmitting protective cover 60 is etched in an etching chamber 54 separate from the reaction chamber 53. In other words, the amorphous silicon film is etched with the sample 64 isolated from the etching radicals. By etching the silicon film, it is possible to prevent etching of the amorphous silicon film already deposited on the sample 64. Therefore, the amorphous silicon is deposited on the surface of the light-transmitting protective cover and loses its transparency, making it difficult to react with laser light. When the required light energy decreases, there is no need to replace the light-transmitting window, take it out of the chamber and clean it, or expose the sample during the process of depositing the amorphous silicon film to the atmosphere, as in the past. An amorphous silicon film of a predetermined thickness can be continuously deposited on a sample in a chamber without having to carry out any steps.As a result, a homogeneous, uniform, and highly pure amorphous silicon film can be efficiently formed on a sample.

On the other hand, according to the apparatus shown in FIG. 3, a homogeneous, uniform, and highly pure amorphous silicon film can be efficiently formed on the sample as described above. Moreover, the disc-shaped light-transmitting protective cover 60 can be used continuously, rather than moving a disposable film close to the light-transmitting window as in the past, so it is made of expensive quartz with excellent light transmittance. It can be formed from materials such as glass.

An improvement in film deposition rate can be achieved.

Further, by using the above-mentioned apparatus shown in FIG. 3, it becomes possible to perform photochemical vapor phase growth by a method different from the method described above.

First, the sample 64 is fixed on the sample stage 58 and heated to a predetermined temperature by a heater (not shown) built into the sample stage 58, and then high-order silane gas is introduced into the reaction chamber 53 from the deposition material gas introduction pipe 57. At the same time, the gas in the reaction chamber 53 is exhausted through the exhaust pipe 631 to achieve a predetermined degree of vacuum.

Next, a laser beam 65 from an ArF excimer laser oscillator (not shown), for example, is irradiated into the reaction chamber 53 through the light transmission window 56 and the disc-shaped light transmission protection cover 60, and at the same time, a disc-shaped light transmission protection cover is formed by the rotating shaft 61. Rotate the cover 60 slowly. At this time, an amorphous silicon film is deposited on the sample 64 by photochemical vapor deposition in which high-order silane introduced into the reaction chamber 53 is excited and decomposed by the laser beam 65.

In addition, in this deposition process, an amorphous silicon film is also deposited on the surface of the region of the rotating disc-shaped light transmission protection cover 60 located at the reaction W53.

After the protective cover 60 is rotated once and an amorphous silicon film is deposited on its entire surface, the supply of higher-order silane gas from the deposition material gas introduction tube 57 is stopped, the laser oscillator is turned off, and the reaction chamber 53 is turned off. Replace the gas inside with an inert gas such as N2.

Next, from the etching gas introduction pipe 59, for example, CF4
After supplying the mixed gas of and 02 into the etching chamber 54 and creating a predetermined degree of vacuum inside the etching chamber 54 through the exhaust pipe 632, a high frequency power source (not shown) is turned on and a pair of flat plates are removed.
Plasma is generated in the etching chamber 54 between the FFs 162a and 62b to radicalize the mixed gas, and the amorphous silicon film deposited on the surface of the light transmission protection cover 60 is transferred to the sample 64 in the reaction chamber 53 by the radicalized gas. Remove by etching while isolated.

Next, in the same manner as described above, the laser beam 65 is irradiated from the laser oscillator into the reaction chamber 53 through the light transmission window 56 and the disc-shaped light transmission protection cover 60, and at the same time, the rotation shaft 61 irradiates the disc-shaped light transmission protection cover 60. slowly rotating the sample 64 to deposit an amorphous silicon film on the sample 64;
The steps of etching and removing the amorphous silicon film on the entire surface of the disc-shaped light transmission protection cover 60 in 54 are repeated to deposit an amorphous silicon film of a predetermined thickness on sample 64J:.

According to the above method, compared to the method of the third embodiment described above, it is possible to continuously deposit an amorphous silicon film while keeping the film deposition rate substantially constant. As a result, the frequency of supplying and stopping the source gas, supplying and stopping the etching gas, turning on and off the laser beam, and turning on and off the high-frequency power source can be reduced, and the deposition efficiency of the amorphous silicon film can be significantly improved.

Furthermore, a photochemical vapor phase growth apparatus having a structure in which a gas introduction chamber is added to the apparatus shown in FIG. 3 described above may be used to perform vapor phase growth of a material film such as an amorphous silicon film. That is, the apparatus shown in FIG.
A gas introduction chamber 66 having a slit 55 is provided on the side surface of the reaction chamber 53 side in 2, and an inert gas introduction pipe 67 from the outside is inserted into this introduction chamber 66. It has an inserted structure.

According to such a configuration, by introducing an inert gas such as Ar gas into the gas introduction chamber 66 from the inert gas introduction pipe 67, the gas is introduced from the introduction chamber 66 to the slit 55- and the slit of the partition wall 52. 55 through the reaction chamber 53
, to the etching chamber 54, the reactions v53,
Etching v54 gases can be prevented from flowing into and out of each other. As a result, the sealing property between the reaction chamber 53 and the etching W54 can be ensured, so the disc-shaped light transmitting protection cover 60 is slowly rotated to seal the reaction chamber 53 as described above.
While the amorphous silicon film is being deposited on the sample 64, the amorphous silicon film deposited on the protective cover 60 can be etched away in the etching chamber 54. Therefore, if such a device is used, the IW product of the amorphous silicon film and the etching of the amorphous silicon film deposited on the disk-shaped light transmitting protective cover can be performed continuously, so that the high optical energy of the laser beam is always used. It is possible to excite and decompose the raw material gas in the same state, and also eliminates the complicated operations of supplying and stopping the raw material gas, supplying and stopping the etching gas, turning on and off the laser beam, and turning on and off the frequency power supply. This makes it possible to further improve the deposition efficiency of the amorphous silicon film. In this case, by using two or more disk-shaped light-transmitting protective covers and reversing the rotating direction of the disk-shaped light-transmitting protective covers, the protection located in the area of the reaction chamber can be protected. The light transmittance of the cover can be made uniform, and it becomes possible to form a material film with a uniform thickness on the sample.

In Example 2.3 above, an inert gas such as Ar or N2 is purged into the space between the light-transmitting window and the light-transmitting protective cover, and a material film is deposited on the sample. The material film may be prevented from being deposited on the surface. In other words, it is possible to suppress the deposition of a material film on the light transmitting window which is not etched in the etching chamber, such as a light transmitting protective cover.

In Example 2.3 above, by providing a light transmission window on the wall of the etching chamber and arranging the light source for generating etching radicals outside the chamber,
The etching gas in the etching chamber may be radicalized by the light from the light source, and the material film deposited on the light transmission protective cover may be etched by the radicalized gas.

In the above Example 1.2, a low pressure mercury lamp is used as a light source,
Although a laser beam was used in the third embodiment, a lamp such as a low-pressure mercury lamp or a xenon lamp, a laser beam, or the like may be selected as the light source depending on the material film to be deposited.

In each of the examples described above, the light source was placed outside the chamber, but
A lamp, such as a low pressure mercury lamp, may be placed within the chamber. In this case, the tube wall of the lamp becomes the light transmitting member.

In each of the above embodiments, as the etching radical generating means,
Although a configuration including flat plate electrodes arranged to face each other and a high frequency power source connected to one of the electrodes was used, the present invention is not limited thereto. For example, a semi-cylindrical electrode may be used as the electrode, and if the chamber has a conductive wall surface, that wall surface can be used as the electrode at ground potential. Furthermore, the electric field connected to the power source can be made of a material that is resistant to the deposited source gas and etching radicals, and can be placed in the chamber.

Furthermore, it may be coiled so as to surround the chamber. Etching radicals may be generated by plasma discharge or photoexcitation in another chamber adjacent to the chamber having the light transmitting member, and the etching radicals may be introduced into the chamber having the light transmitting member.

In each of the above examples, higher-order silane was used as the material gas to be deposited, but monosilane mixed with mercury vapor (SiH+
) can be used. Furthermore, when depositing a single metal film, halides, carbonyl compounds, and hydrides can be used.

In the above embodiments, an amorphous silicon film is used as an example of the material film, but the present invention can be similarly applied to the deposition of other material films such as silicon nitride or silicon oxide by introducing ammonia or an oxidizing gas.

〔Effect of the invention〕

As described in detail above, according to the present invention, the material film deposited on the inner surface of the light transmitting member is removed by etching in the chamber without etching the material film in the process of being deposited on the sample. INDUSTRIAL APPLICATION It is possible to provide a photochemical vapor deposition method and an apparatus for the same, which enables the deposition of a material film and, in turn, can efficiently deposit a homogeneous, uniform, and highly pure material film.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a photochemical vapor growth apparatus in Example 1 of the present invention, FIG. 2 is a cross-sectional view showing a photochemical vapor growth apparatus in Example 2 of the present invention, and FIG. 3 is a cross-sectional view showing a photochemical vapor growth apparatus in Example 2 of the present invention. FIG. 4 is a cross-sectional view of a photochemical vapor deposition apparatus according to another embodiment of the present invention, and FIG. 5 is a conventional photochemical vapor deposition apparatus. FIG. 2 is a sectional view showing the device. 11.31.51...Chamber, 13.33.53.
...Reaction chamber, 14...Waiting room, 16.36.56...
・Light transmission window, 17.37.57... Deposited raw material gas introduction pipe, 18.41.59... Etching residue introduction pipe,
19.38--Low pressure mercury lamp, 21a, 21b14
2a, 42b, 62a, 62b... flat plate electrode, 2
2.43...High frequency power supply, 23.44...Transport plate,
24.40.58...Sample stand, 261.262.47
1.472.63t, 632...exhaust pipe, 27.4
8.64...Sample, 45.60...Light transmission protective cover, 61...Rotating shaft, 66...Gas introduction, 67...
・Inert gas introduction pipe. Applicant Sub-Agent Patent Attorney Takehiko Suzue'HIWI Figure 2 Figure 3

Claims (18)

[Claims] (1) A step of introducing a material gas to be deposited into a chamber and irradiating light into the chamber through a light-transmitting member to excite the gas and depositing a predetermined material film on a sample placed in the chamber. and a step of etching away the material film on the light transmitting member in a state where etching radicals do not reach the sample on which the material film has been deposited. (2) The photochemical vapor deposition method according to claim 1, characterized in that light emitted from a lamp is used as the light. (3) The photochemical vapor deposition method according to claim 1, characterized in that a laser beam is used as the light. (4) A chamber having at least two or more chambers, a light transmitting member provided on the wall of the chamber corresponding to at least one of these chambers, and inserting into the chamber provided with this light transmitting member. an etching gas introduction pipe inserted into the chamber in which the light transmitting member is provided; a light source that irradiates light for exciting the raw material gas introduced into the chamber from the introduction tube; and a light source disposed corresponding to the light transmitting member, which radicalizes the gas introduced into the chamber from the etching gas introduction tube, and radical generating means for supplying the radicals to the vicinity of the light transmitting member; a transport means for transporting the sample into the chamber in which the light transmitting member is provided and transporting the same sample to another chamber during etching in the chamber; A photochemical vapor phase growth apparatus characterized by comprising: (5) The photochemical vapor deposition apparatus according to claim 4, wherein the light source is a lamp. (6) The photochemical vapor deposition apparatus according to claim 4, wherein the light source is a laser oscillation device. (7) The radical generating means includes a pair of electrodes arranged facing each other outside the chamber in correspondence with the light transmitting member;
5. The photochemical vapor deposition apparatus according to claim 4, further comprising a high frequency power source connected to one of these electrodes. (8) The photochemical vapor deposition apparatus according to claim 4, wherein the transport means has a shutter function that closes the entrances and exits of the partition walls that partition each chamber. (9) The photochemical gas according to claim 4, wherein another chamber into which the sample is transported by the transport means during etching of the chamber provided with the light-transmitting member is a waiting chamber for the specimen. Phase growth device. (10) Another chamber in which the sample is transported by a transport means during etching of the chamber provided with the light-transmitting member is provided with a light-transmitting member and a deposition material gas introduction pipe, similar to the chamber provided with the light-transmitting member. , an etching gas introduction pipe is arranged,
5. The photochemical vapor deposition apparatus according to claim 4, wherein a light source and a radical generating means are arranged outside the photochemical vapor deposition apparatus. (11) A chamber having at least two or more chambers;
A light transmitting window provided in the wall of the chamber corresponding to the first chamber in which the sample is placed among these chambers, and a light transmitting window adjacent to the window;
a light transmitting member made of a light transmitting protective cover that is movable to a second chamber adjacent to the first chamber; a deposition material gas introduction pipe inserted into the first chamber; and an etching member inserted into the second chamber. a gas inlet pipe, and a first gas inlet pipe disposed outside the chamber corresponding to the light transmission window, from the to-be-deposited raw material gas inlet pipe.
a light source for irradiating light to excite the source gas introduced into the chamber; and a light source disposed corresponding to the second chamber for radicalizing the gas introduced into the second chamber from the etching gas introduction pipe. radical generating means, and conveying means for conveying the light transmitting protective cover to the first chamber and conveying the protective cover to the second chamber after a substance film deposition process in the first chamber. A photochemical vapor phase growth device featuring: (12) The photochemical vapor deposition apparatus according to claim 11, wherein the light source is a lamp. (13) The photochemical vapor deposition apparatus according to claim 11, wherein the light source is a laser oscillation device. (14) Two second chambers are arranged on both sides of the first chamber, and an etching gas introduction pipe and a radical generating means are arranged in each second chamber, and the first chamber is arranged in the transport means.
Two light transmitting protective covers are installed so as to correspond to the chamber and one or the other second chamber, and when the substance film of the sample is deposited in the first chamber, the substance film is deposited in one or the other second chamber. 12. The photochemical vapor deposition apparatus according to claim 11, characterized in that the photochemical vapor growth apparatus is configured to perform etching of the light transmitting protective cover. (15) The photochemical vapor deposition apparatus according to claim 11, wherein the conveying means has a shutter function for closing the entrances and exits of partition walls that partition each chamber. (16) The light-transmitting protective cover is arranged in the shape of a disk and extends between the first and second chambers, and the conveying means includes a rotating shaft that is pivotally attached to the disk-shaped protective cover, and a drive for the rotating shaft. 12. The photochemical vapor growth apparatus according to claim 11, characterized in that it is comprised of a member. (17) The radical generating means is composed of a pair of electrodes that are arranged opposite to each other so as to sandwich a light transmission protective cover inside or outside the second chamber, and a high frequency power source connected to one of these electrodes. 17. A photochemical vapor deposition apparatus according to claim 11, 14, or 16, characterized in that the apparatus is characterized in that: (18) The radical generating means is a light source provided inside or outside the second chamber so as to correspond to the light transmission protective cover, and for converting into radicals the gas introduced into the chamber from the etching gas introduction pipe. Claim 1 characterized by
The photochemical vapor deposition apparatus according to item 1, item 14, or item 16.