JP2000150938A - FORMATION METHOD OF Ib-IIIb-VIb2 COMPOUND SEMICONDUCTOR THIN FILM AND SOLAR CELL ELEMENT HAVING THE THIN FILM FORMED BY THE METHOD - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of obtaining a thin film, having a resistivity suitable as the light-absorbing layer of a solder cell in a method for forming an Ib-IIIb-VIb2 compound semiconductor (CuInS2) thin film by a CVD method (chemical vapor deposition method), using an organic metallic compound as its raw material. SOLUTION: First, raw gases of three components are introduced in a reaction layer 1 to cause a CuInS2 thin film to phase-grow on a substrate 4, in such a state that the temperature of the substrate 4 is held at a temperature of 440 deg.C. The raw gases of the three components are (H2S/H2) gas, Ar gas containing vapor made of a Cu raw material 71 and Ar gas containing vapor made of an In raw material 81. Then, only the (H2S/H2) gas is introduced in the layer 1 to perform heat treatment on the thin film, in a state such that the temperature of the substrate 4 is held at a temperature of 550 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical vapor deposition method (CVD: Chemical Vapor Deposition) of an Ib-IIIb-VIb group ₂ compound semiconductor thin film used as a light absorbing layer of a solar cell or the like.
or Deposition).

[0002]

_2. Description of the Related Art Ib-IIIb-VIb group ₂ compound semiconductors are materials that are expected to be used as light absorbing layers in solar cells. In particular, Cu (In _x , Ga _(1-x) ) (S
e _y , S _(1-y) ) ₂ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1) has been actively studied as a material for a solar cell which has high conversion efficiency and can be reduced in cost. . Cu (In _x , Ga _{(1
-x)) (Se y, S} (1-y)) The method of forming ₂ thin film, vacuum deposition, chalcogenide method (first Cu (an In _x,
Various methods such as a method of forming a Ga _(1-x) ) thin film and heat-treating the same in an S or Se-containing gas atmosphere), an electrodeposition method, a CVD method and the like have been studied.

[0003] Among the CVD method, since the deposition speed is high lower cost of the device compared to other methods, be advantageous for forming a thin film of large area, Ib-IIIb-VIb ₂
Attention has also been paid to a method for forming a group III compound semiconductor thin film. Regarding the formation of the Ib-IIIb-VIb group ₂ compound semiconductor thin film by the CVD method, see "Solid Stat".
e phenomena 37-38 (1994) p5
03-508 "describes that a CuInSe ₂ thin film was formed by a CVD method under atmospheric pressure.

In this document, a solution prepared by dissolving copper (II) hexafluoroacetylacetonate in trimethylamine is used as a raw material of copper (Cu), and indium (In) is used.
Using triethylindium as raw material for selenium (S
e) Hydrogen selenide is used as a raw material. That is, an organometallic compound is used as a raw material for copper and indium. In addition, hydrogen is used as a carrier gas for the copper raw material and the indium raw material, and hydrogen selenide diluted with hydrogen gas is introduced. In addition, the vapor phase growth temperature is set to 4
It is set to 00 ° C.

[0005]

However, in the above-mentioned prior art, there is a problem that the resistivity of the obtained thin film is increased due to insufficient crystallization. In particular, In
There excess relative to Cu (1 in atomic ratio: more than 1) CuInS ₂ thin film included but is suitable as a light absorbing layer of the solar cell, In is the method described excess CuInS ₂ to the literature ( When a film is formed (using hydrogen sulfide instead of hydrogen selenide), the resulting CuInS ₂ thin film has a resistivity of 10 ⁷
(Ω · cm) or more. Such a thin film having extremely high resistivity cannot be used as a light absorbing layer of a solar cell.

The present invention has been made in view of such problems of the prior art, and a method for forming an Ib-IIIb-VIb group ₂ compound semiconductor thin film by a CVD method using an organometallic compound as a raw material. It is an object of the present invention to provide a method for obtaining a thin film having an appropriate resistivity as a light absorbing layer of a solar cell.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, have obtained the following findings and completed the present invention. I obtained by the method described in the aforementioned document
The reason why the crystallinity of the b-IIIb-VIb group ₂ compound semiconductor thin film is not sufficient and the resistivity is high is that the vapor phase growth temperature is 4
Since the temperature is as low as 00 ° C., the group VIb element, the group Ib element and the
It is considered that the reaction with the group IIb element is insufficient. Therefore, it is considered that the resistivity of the obtained thin film can be suppressed to an appropriate value by increasing the vapor phase growth temperature so that the reaction between the Group VIb element, the Group Ib element, and the Group IIIb element is sufficiently performed. .

However, in the CVD method using an organometallic compound as a raw material, the carbon content in the obtained thin film increases as the vapor phase growth temperature increases. If the carbon content in the thin film is high, the resistivity of the thin film will be significantly lower.
Hall measurement confirmed that the phenomenon that the resistivity of the thin film obtained when the vapor phase growth temperature was increased was not caused by an increase in the hole concentration.
This phenomenon is considered to be caused by carbon segregating at the grain boundaries of the Ib-IIIb-VIb group ₂ compound semiconductor, and the segregated carbon becomes a path of current.

As described above, the Ib-IIIb-VIb group ₂ compound semiconductor thin film cannot be used as a light absorbing layer of a solar cell even if its resistance is too low. That is, simply CVD
It has been found that a thin film having an appropriate resistivity as a light absorbing layer of a solar cell cannot be obtained only by increasing the vapor phase growth temperature by the method.

[0010] Based on the above findings, the present invention provides a chemical vapor deposition method using an organometallic compound as a raw material.
In a method of forming a thin film made of an Ib-VIb group ₂ compound semiconductor on a substrate, a source gas of a group Ib element, a source gas of a group IIIb element, and a source gas of a group VIb element are introduced into a reactor. The phase growth reaction is carried out at a predetermined temperature (a temperature relatively higher than the temperature at which film formation is possible and the carbon content is kept low, for example, the same temperature as the vapor phase growth temperature in the conventional method) for a predetermined time (when the predetermined film thickness is (Time required for obtaining), and then the atmosphere of the source gas of the group VIb element (for example,
A source gas of a group VIb element;
A method for forming an Ib-IIIb-VIb group ₂ compound semiconductor thin film, wherein the heat treatment is performed in an atmosphere not containing a source gas of an Ib group element.

According to the method of the present invention, even if a thin film having a low content of the group VIb element is formed by performing the vapor phase growth reaction at a temperature as low as the conventional one (for example, 400 ° C.), it is performed afterwards. The heat treatment replenishes the thin film formed by the vapor phase growth reaction with the Group VIb element, and the reaction between the Group VIb element, the Group Ib element, and the Group IIIb element is sufficiently performed. Therefore, by performing the heat treatment after performing the vapor phase growth reaction at a temperature as low as the conventional temperature, it is possible to sufficiently reduce the carbon content of the obtained thin film while sufficiently increasing the crystallinity of the thin film obtained after the heat treatment. Can be. As a result, an appropriate resistivity (for example, 1.0 × 10 ^{2 to} 1.0 × 10 ⁴ Ω · c) as a light absorbing layer of the solar cell is obtained by the CVD method.
m) is obtained.

The present invention also provides a solar cell device comprising, as a constituent material, an Ib-IIIb-VIb group ₂ compound semiconductor thin film formed by the method of the present invention. The conversion efficiency of this solar cell device is as follows. The conversion efficiency is remarkably higher than the conversion efficiency of a solar cell element including the Ib-IIIb-VIb group ₂ compound semiconductor thin film formed as a constituent material by the method of the related art.

In the method of the present invention, the lower the substrate temperature during the vapor phase growth reaction, the lower the carbon content in the thin film. Therefore, the substrate temperature during the vapor phase growth reaction is preferably 490 ° C. or lower, for example. More preferably, the temperature is set to 450 ° C. or lower. In the method of the present invention, the substrate temperature during the vapor phase growth reaction is preferably set to 450 ° C. or lower, and the substrate temperature during the heat treatment is preferably set to 500 ° C. or higher.

When the substrate temperature during the vapor phase growth reaction is 450 ° C. or lower, the carbon content in the thin film can be sufficiently reduced. The lower limit of the substrate temperature during the vapor phase growth reaction is the lowest temperature at which a thin film having a predetermined performance can be formed, for example, 300 ° C.
Or it is 350 ° C. The effect obtained by the heat treatment increases as the substrate temperature during the heat treatment increases, but if the substrate temperature during the heat treatment is too high, the substrate is likely to be deformed. At a temperature that does not cause For example, when the substrate is soda-lime glass, the substrate temperature during the heat treatment is set to 560 ° C. or less, which is the heat-resistant temperature of soda-lime glass.

The pressure of the heat treatment atmosphere is preferably 50 Torr or more. If the pressure of the heat treatment atmosphere is lower than 50 Torr, the VIb group element may not be sufficiently replenished during the heat treatment. The heat treatment may be performed continuously after the end of the vapor phase growth reaction in the same reactor where the vapor phase growth reaction was performed, or in a separate heat treatment furnace from the reactor where the vapor phase growth reaction was performed. The transfer may be performed by moving the substrate. When another heat treatment furnace is not provided with a pressure reducing device, the pressure of the heat treatment atmosphere may be set at atmospheric pressure (760 Torr).

The raw material gas of each element is a gas containing a raw material containing the element as a constituent element. When the raw material is a solid or liquid, its vapor is converted to argon, nitrogen, hydrogen, hydrogen and argon. Or a carrier gas composed of a mixed gas of hydrogen and nitrogen or the like, and introduced into the reactor. When this raw material is a gas, it is introduced into the reactor as it is or after being diluted with any of the aforementioned gases.

In the method of the present invention, it is preferable to introduce hydrogen into the reactor during the vapor phase growth reaction by using hydrogen as such a carrier gas or diluting gas. Thus, since hydrogen is present in the film formation atmosphere by vapor phase growth, the amount of carbon mixed into the thin film is reduced.

Ib-I of interest in the method of the present invention
As the IIb-VIb group ₂ compound semiconductor, Cu (I
_{n x, Ga (1-x} )) (Se y, S (1-y)) 2 (0 ≦ x ≦
1,0 ≦ y ≦ 1). This compound semiconductor contains CuInS ₂ . In the method of the present invention, Cu (I
n _x, Ga _(1-x)) in the case of forming a _{(Se y, S (1-} y)) 2 thin film, an organic copper compound expressed as Cu material in (1) below, In and Ga (M (C
_{n H 2n + 1) 3)} (M is In or Ga), S and Se
It is preferable to use H ₂ X (X is S or Se) as a raw material of the compound.

[0019]

Embedded image (In the formula, n is any one of 0, 1, 2, and 3.) By using each of these materials, the growth rate of the thin film is increased, and the composition controllability is also improved.

[0020]

Embodiments of the present invention will be described below. FIG. 1 is a schematic configuration diagram showing a CVD apparatus capable of performing a method corresponding to an embodiment of the present invention.

This CVD apparatus is a vertical type CVD apparatus, and a raw material gas is introduced from the lower side of the reactor 1. A mixer 2 is provided directly below the reactor 1, and a mixed gas introduction pipe 21 is provided above the mixer 2. The mixed gas introduction pipe 21 extends upward from the upper part of the mixer 2 by a predetermined length, and the upper end thereof is disposed slightly below the susceptor 3 disposed in the reactor 1 (the side on which the substrate 4 is mounted). Have been.

The mixer 2 is a chamber having a mixing space of a predetermined volume, and does not have a stirring mechanism for stirring the introduced gas. The gas introduced into the mixer 2 stays therein for a time corresponding to the introduction speed (flow rate) and the volume of the mixer 2, and then flows from the mixed gas introduction pipe 21 to the reactor 1.

The susceptor 3 is made of carbon. Reactor 1
A high frequency induction coil 11 for heating the susceptor 3 is provided on the outer periphery of the susceptor 3. Above the reactor 1, a vacuum pump 5 is provided via a throttle valve 51. By adjusting the opening of the throttle valve 51 according to the set pressure and operating the vacuum pump 5, the inside of the reactor 1 and the inside of the mixer 2 can be maintained at a set pressure lower than the atmospheric pressure. Further, a thermocouple 31 for measuring the temperature of the susceptor 3 is provided on the upper part of the reactor 1.

Downstream ends of pipes 6, 7, and 8 for independently introducing three raw material gases are connected to one side of the mixer 2. In this embodiment, since a CuInS ₂ thin film is formed, hydrogen sulfide (H ₂ S) is converted to hydrogen (H ₂ S) at the upstream end of the pipe 6.
₂₎ supplying the diluted gas (H ₂ S / H ₂₎ is connected to a supply source 61. (H ₂ S /
A flow controller 62 for adjusting the flow rate of the H ₂ ) gas into the mixer 2 is provided.

The upstream end of the pipe 7 is connected to a vaporization vessel 72 containing a Cu raw material 71. The upstream end of the pipe 8
It is connected to a vaporization container 82 containing n raw materials 81. Each of the vaporization containers 72 and 82 is provided with piping 73 and 83 for introducing a carrier gas into the inside. The upstream end of the pipe 73 is connected to an Ar gas supply source 9 that supplies argon (Ar) gas used as a carrier gas. Piping 8
3 branches from the pipe 73.

This apparatus is adapted to a case in which liquids are used at room temperature as the Cu raw material 71 and the In raw material 81, and a bubbling method is employed in which a carrier gas is introduced into these liquids to generate bubbles. It is. Therefore, the pipes 73 and 83 are arranged such that the downstream ends reach the liquids in the vaporization containers 72 and 82. The upstream ends of the pipes 7 and 8 are arranged in the upper spaces of the vaporization containers 72 and 82.

The pipe 73 is located downstream of the branch point of the pipe 83.
Adjust the flow rate of Ar gas into the vaporization vessel 72 at the side position
A flow regulator 74 is provided. The pipe 83 has Ar
Flow controller 8 for controlling the flow rate of gas into vaporization vessel 82
4 are provided. Thereby, the supply of the Ar gas is started.
Then, Ar gas is introduced into the liquid in each of the vaporization containers 72 and 82.
Foams form upon entry. Accordingly, the vapor of each liquid is effective.
It is carried to Ar gas at a constant rate, and is fed from the pipes 7 and 8 to the mixer 2.
be introduced. Also, (H_TwoS / H _Two) Start gas supply
Then, from the pipe 6 to the mixer 2 (H_TwoS / H_Two)Gas
be introduced.

Therefore, if the supply of the Ar gas and the supply of the (H ₂ S / H ₂ ) gas are started simultaneously using this apparatus, the Ar gas, the vapor of the copper compound 71, the vapor of the indium compound 81, and the (H ₂ S / H ₂ ) gas is supplied to the mixer 2
After being mixed in the reactor, the reactor 1
Is introduced into the vicinity of the substrate 3. Example 1 First, a vapor phase growth reaction of a CuInS ₂ thin film was performed under the following conditions using the apparatus of FIG.

As the liquid Cu raw material 71, (vinyltrimethylsilane) hexafluoroacetylacetonato copper (I) was used. This compound is represented by the following formula (2). In the following, this compound is referred to as Cu (hfac) VM
Abbreviated as TS.

[0030]

Embedded image As the liquid In raw material 81, triethylindium (I
n (C ₂ H ₅ ) ₃ ) was used. The (H ₂ S / H ₂ ) gas had an H ₂ S concentration of 5% by volume.

The ratio of each component in the mixer 2 is C
The following adjustments were made so that u: In: S = 23: 26: 51. By adjusting the flow controllers 62, 74, and 84, the flow rate of the (Cu (hfac) VMTS + Ar) gas is 31 SCCM, the flow rate of the (triethylindium + Ar) gas is 19 SCCM, and the flow rate of the (H ₂ S / H ₂ ) gas is 1
74 SCCM. The temperature of Cu (hfac) VMTS and triethylindium was adjusted to 6 ° C. by adjusting the temperatures of the vaporizers 72 and 82.

As the substrate 4, a soda-lime glass substrate and a soda-lime glass substrate on which a molybdenum (Mo) thin film having a thickness of 1 μm was formed by a sputtering method were prepared. For the substrate on which the Mo thin film was formed, a CuInS ₂ thin film was formed on the Mo thin film surface. The temperature (substrate temperature) of the susceptor 3 was maintained at 440 ° C. by adjusting the current input value to the high-frequency induction coil 11 according to the output value from the thermocouple 31.

After adjusting the opening of the throttle valve 51 so that the pressure in the reactor 1 became 5 Torr, the vacuum pump 5 was operated. The pressure in the mixer 2 was higher than the pressure in the reactor 1, in this case 50 Torr. In this state, the supply of the Ar gas and the supply of the (H ₂ S / H ₂ ) gas are simultaneously started, so that the three-component raw material gas is mixed in the mixer 2 and then introduced into the vicinity of the substrate 3 in the reactor 1. did. The vapor phase growth reaction time was 1 hour.

Next, without removing the substrate 4 from the susceptor 3,
Heat treatment was performed in the reactor 1 under the following conditions.
By stopping the supply of the Ar gas to the vaporizers 72 and 82 and closing the valves of the pipes 7 and 8, Cu gas is removed.
(Hfac) The supply of VMTS and triethylindium into the mixer 2 was stopped. The (H ₂ S / H ₂ ) gas was continuously supplied at a flow rate of 174 SCCM. The temperature of the susceptor 3 (substrate temperature) was adjusted to be maintained at 550 ° C.
The pressure in the reactor 1 was adjusted to 100 Torr by adjusting the throttle valve 51. The heat treatment time was 1 hour.

As described above, by performing the heat treatment after the vapor phase growth reaction, a CuInS ₂ thin film was formed on the substrate. When the thickness of the obtained thin film was measured with a step meter, it was 1.5 μm.
m. When the composition of this thin film was analyzed by EDX (energy dispersive X spectrometer), it was found that Cu: In: S
= 23.0: 26.0: 51.0. When the resistivity of the CuInS ₂ thin film directly formed on the glass substrate was measured by a four-probe method, it was found to be 1.0 × 10 ³ (Ω · c).
m).

The obtained CuInS_TwoCarbon concentration in thin film
With a secondary ion mass spectrometer (SIM manufactured by ATOMIKA)
S4100), 1.0 × 10¹⁶
(Cm ^-3)Met. Next, the layers shown in FIG.
A solar cell having the configuration was manufactured.

First, an electrode layer 20 was formed on a glass substrate 10 made of soda lime glass by sputtering.
A Mo thin film was formed with a thickness of 1.0 μm. On this, a CuInS ₂ thin film having excess In relative to Cu was formed as a p-type semiconductor layer 30 to a thickness of 1.5 μm.
This CuInS ₂ thin film was formed by the same method as described above. When the composition of the obtained CuInS ₂ thin film was analyzed by EDX, Cu: In: S = 23.0: 26.0: 5.
1.0.

Next, an n-type semiconductor layer 40 is formed on the CuInS ₂ thin film (p-type semiconductor layer) 30 by a solution growth method.
A CdS thin film was formed with a thickness of 50 nm. Furthermore, a film in which Al was doped with ZnO at a ratio of 2 at% was formed to a thickness of 1.0 μm as an electrode layer 50 by RF sputtering.

When the conversion efficiency of this solar cell was measured by a solar simulator (AM 1.5, 100 mW / cm ² ), it was 8%. Comparative Example 1 A vapor phase growth reaction of a CuInS ₂ thin film was carried out using the apparatus shown in FIG. However, no heat treatment was performed on the CuInS ₂ thin film after the vapor phase growth reaction.

Thus, a CuInS ₂ thin film was formed on the substrate only by the vapor phase growth reaction. When the thickness of the obtained CuInS ₂ thin film was measured by a step gauge, it was 1.5 μm. When the composition of CuInS ₂ was measured by the same method as in Example 1, Cu: In: S = 24.0: 27.0: 4.
9.0.

In addition, CuI directly formed on a glass substrate
When the resistivity of the nS ₂ thin film was measured by the four probe method,
Due to the high resistivity, measurement was not possible with this method. The upper limit of the resistivity measurable by this method is 1.0 × 10 ^7.
(Ω · cm), the resistivity of this CuInS ₂ thin film is 1.0 × 10 ⁷ (Ω · cm) or more. CuIn
When the concentration of carbon in the S ₂ thin film was measured by the same method as in Example 1, it was 1.0 × 10 ¹⁶ (cm ⁻³ ).

The CuInS ₂ thin film obtained by this method is
The S content was smaller than that of the CuInS ₂ thin film obtained in Example 1. As a result, the Cu obtained by this method
The resistivity of the InS ₂ thin film is significantly higher than that of the CuInS ₂ thin film obtained in Example 1.

Next, using the CuInS ₂ thin film obtained by this method as the p-type semiconductor layer 30, a solar cell having the layer structure shown in FIG. 2 was produced. Except for the method of forming the p-type semiconductor layer 30, the same method as in Example 1 was employed. The conversion efficiency of this solar cell was measured using a solar simulator (AM 1.5, 100 mW
/ Cm ₂ ) was 2%. Comparative Example 2 Using the apparatus of FIG. 1, a vapor growth reaction of a CuInS ₂ thin film was performed in the same manner and under the same conditions as in Example 1 except for the following points.

The flow rate of (Cu (hfac) VMTS + Ar) is adjusted to 37 by adjusting the flow rate adjusters 62, 74 and 84.
SCCM, the flow rate of (triethylindium + Ar) is 1
6 SCCM, (H ₂ S / H ₂ ) gas flow rate of 134 SC
CM. The temperature of the susceptor 3 (substrate temperature) is 550 ° C.
It was adjusted so that it would be maintained.

No heat treatment was performed on the CuInS ₂ thin film after the vapor phase growth reaction. That is, a CuInS ₂ thin film was formed on the substrate only by the vapor phase growth reaction. When the thickness of the obtained CuInS ₂ thin film was measured by a step gauge, it was 1.5 μm. Example 1 Composition of CuInS ₂
Cu: In: S = 23.
0: 26.0: 51.0.

In addition, CuI directly formed on a glass substrate
When the resistivity of the nS ₂ thin film was measured by the four probe method,
0.6 (Ω · cm). When the concentration of carbon in the CuInS ₂ thin film was measured in the same manner as in Example 1,
It was 1.0 × 10 ²⁰ (cm ⁻³ ).

The composition of the CuInS ₂ thin film obtained by this method was the same as that of the CuInS ₂ thin film obtained in Example 1. However, the carbon content was as high as 10,000 times that of Example 1 and Comparative Example 1. As a result, the CuInS ₂ thin film obtained by this method was obtained in Example 1.
The resistivity was remarkably lower than that of the CuInS ₂ thin film obtained in 1.

Next, using the CuInS ₂ thin film obtained by this method as the p-type semiconductor layer 30, a solar cell having a layer structure shown in FIG. 2 was produced. Except for the method of forming the p-type semiconductor layer 30, the same method as in Example 1 was employed. The conversion efficiency of this solar cell was measured using a solar simulator (AM 1.5, 100 mW
/ Cm ₂ ) was 0.5%.

In the method of this embodiment, the reactor 1
Is provided immediately before the mixing, and each raw material gas is mixed in the mixer 2 so that the ratio of Cu, In and S becomes a set value. , The variation in the film composition can be reduced as compared with the case where the reactor 1 without such a mixer 2 is used.

[0050]

As described above, according to the method of the present invention, Ib-IIIb-VIb _{2 formed} by the conventional CVD method.
Compared with the method of forming a group III compound semiconductor thin film, a thin film having a suitable resistivity as a light absorbing layer of a solar cell is obtained.

According to the solar cell element of the present invention, the conversion efficiency can be significantly increased as compared with the solar cell element provided with the Ib-IIIb-VIb group ₂ compound semiconductor thin film formed by the conventional method.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a CVD apparatus capable of performing a method corresponding to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view illustrating a layer configuration of a solar cell manufactured in the embodiment.

[Explanation of symbols]

Reference Signs List 1 reactor 2 mixer 3 susceptor 4 substrate 5 vacuum pump 6 S source supply pipe 7 Cu source supply pipe 8 In source supply pipe 9 Ar gas supply source 10 glass substrate 11 high frequency induction coil 20 electrode layer 21 mixed gas introduction Tube 30 CuInS ₂ thin film (p-type semiconductor layer) 31 thermocouple 40 n-type semiconductor layer 50 electrode layer 61 (H ₂ S / H ₂ ) gas supply source 62 flow regulator 71 Cu raw material 72 vaporizer 73 piping 74 flow regulator 81 In raw material 82 Vaporizer 83 Piping 84 Flow rate regulator

 ──────────────────────────────────────────────────の Continuation of the front page (71) Applicant 598153191 M3D, Materials Developments Design and Devices SA M3D, Materials Development Opportunity Design & Devices SA France, Gaillard F-74240, Lu-du-Jardin, 16 B. (72) Inventor Takayuki Watanabe, 2nd, Samejima, Fuji City, Shizuoka Prefecture Asahi Kasei Kogyo Co., Ltd. (72) Hidenobu Nakazawa, 1st, 2nd Samejima Island, Fuji City, Shizuoka Prefecture Asahi Kasei, R-des Jardins, F-74240 Industrial Co., Ltd. (72) Inventor Jane Marco Aggro France, Gairard F-74240, Lou de Jardin, 16 M3 D, Materials Developments Designs and Devices S F term (reference) 4K030 AA11 AA17 AA24 BA01 BA08 BA11 BA24 BA32 BA53 BA55 BA56 CA06 CA17 DA02 DA09 FA04 JA10 LA12 LA14 LA16 5F045 AA04 AB40 AC07 AC09 AC16 AD07 AD08 AE AF10 BB07 BB16 CA13 DA66 DP05 DQ04 EE03 EE05 EK03 HA16 5F051 AA10 CB12 CB24 GA03

Claims (7)

[Claims] 1. A method of forming a thin film made of an Ib-IIIb-VIb Group ₂ compound semiconductor on a substrate by a chemical vapor deposition method using an organometallic compound as a raw material, After introducing a source gas, a source gas of a group IIIb element, and a source gas of a group VIb element, performing a vapor phase growth reaction at a predetermined temperature for a predetermined time, performing heat treatment in an atmosphere of the source gas of the group VIb element. A method for forming an Ib-IIIb-VIb group ₂ compound semiconductor thin film, which is characterized in that: 2. The Ib-IIIb-VIb according to claim 1, wherein the substrate temperature during the vapor phase growth reaction is 450 ° C. or lower, and the substrate temperature during the heat treatment is 500 ° C. or higher.
_A method for forming a group _II compound semiconductor thin film. 3. Ib-I according to claim 1 or 2, wherein hydrogen is introduced into the reactor during the vapor phase growth reaction.
IIb-VIb A method for forming a Group ₂ compound semiconductor thin film. 4. The group Ib-IIIb-VIb group ₂ compound is C
u (In _x , Ga _{(1 -x)} ) (Se _y , S _(1-y) ) ₂ (0
≦ x ≦ 1, 0 ≦ y ≦ 1), Ib-IIIb-VIb according to any one of claims 1 to 3,
_A method for forming a group _II compound semiconductor thin film. 5. An organic copper compound represented by the following formula (1) as a Cu raw material, and M (C _n
H _{2n +} 1) ₃ (M is In or Ga), H ₂ X as a starting material for S, and Se (X is Ib-IIIb-VIb ₂ group compound according to claim 4, wherein the use of S or Se) A method for manufacturing a semiconductor thin film. Embedded image (In the formula, n is any one of 0, 1, 2, and 3.) 6. The group Ib-IIIb-VIb group ₂ compound is C
uInS ₂ , an organocopper compound represented by the following formula (2) as a Cu raw material, triethylindium (In (C ₂ H ₅ ) ₃ ) as a raw material for In, and H ₂ S as a raw material for S.
Ib-III according to claim 4, wherein
A method for producing a b-VIb group ₂ compound semiconductor thin film. Embedded image 7. A solar cell device comprising, as a constituent material, an Ib-IIIb-VIb group ₂ compound semiconductor thin film produced by the method according to claim 1. Description: