JP2010129619A - Solar cell using silicon particulate, optical sensor, and method of manufacturing them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problems that manufacture cost becomes high since an expensive vacuum device is used in a conventional silicon amorphous solar cell and that manufacture cost becomes high since much silicon crystals and polysilicon crystals of high purity are used in a silicon crystal-type solar cell. <P>SOLUTION: In the highly efficient solar cell and optical sensor of high sensitivity, a pn particulate mix layer of an n-type silicon particulate covered by an organic thin film and a p-type silicon particulate covered by the organic thin film is formed between an n-type silicon particulate layer covered by the organic thin film which is covalently bonded to a surface and a p-type silicon particulate layer covered by the organic thin film which is covalently bonded to the surface. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a semiconductor device and a manufacturing method thereof. More specifically, the present invention relates to a solar cell and an optical sensor using fine particles obtained by imparting thermal reactivity or photoreactivity, radical reactivity or ion reactivity to the surface of semiconductor silicon fine particles, and a method for producing the same.

In particular, in the present invention, the pn junction layer is composed of a mixed layer of n-type silicon particles and p-type silicon particles.

Conventionally, as a method for forming a pn junction layer of a semiconductor device such as a solar cell or an optical sensor, impurity diffusion or a CVD method is used. Specifically, silicon amorphous solar cells and photosensors with a pn junction layer formed on the glass substrate surface using plasma CVD, silicon crystals and polysilicon crystals are cut and processed into a plate shape, and then impurity diffusion is performed A silicon crystal solar cell or a photosensor having a pn junction layer is known. For example, there are the following patents.
JP 10-247629,

Furthermore, recently, as solar cells and photosensors other than those described above, print-type solar cells and photosensors using silicon fine particles and a reactive monomolecular film are known. For example, there are the following patents.
JP2007-173516

However, since the conventional silicon amorphous solar cell uses an expensive vacuum device, there is a drawback that the manufacturing cost increases. In addition, the silicon crystal solar cell has a drawback in that the manufacturing cost increases because a large amount of high-purity silicon crystal or polysilicon crystal is used.

The present invention provides a printed solar cell or photosensor using silicon fine particles, which can significantly reduce the cost compared to conventional amorphous silicon type or silicon crystal type solar cells or photosensors while using silicon. The object is to provide a solar cell or photosensor with higher efficiency or higher sensitivity.

A first invention provided as means for solving the above-described problems is that at least an n-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface and a p coated with an organic thin film covalently bonded to the surface. And a p-type fine particle mixed layer of n-type silicon fine particles covered with the organic thin film and p-type silicon fine particles covered with the organic thin film, It is a light sensor.

A second invention is the solar cell and the optical sensor according to the first invention, wherein at least the organic thin film covalently bonded to the surface is a monomolecular film.

According to a third invention, in the first and second inventions, as the organic thin film covalently bonded to at least the surface, two kinds of thin films each containing a functional group that reacts with each other are used. It is a solar cell and a photosensor characterized by being cured and formed into a layer by reaction between groups.

According to a fourth invention, in the first and second inventions, a thin film containing at least one kind of reactive functional group is used as the organic thin film covalently bonded to the surface, and each layer has the reactive functional group. It is a solar cell and an optical sensor characterized in that they are cross-linked with a cross-linking agent and cured into a layer.

A fifth invention is a solar cell and an optical sensor according to any one of the first to fourth inventions, wherein the mixed layer is formed using silicon fine particles having different particle diameters.

The sixth invention is an organic film containing n-type or p-type silicon fine particles covered with an organic film containing a first reactive functional group covalently bonded to the surface and a second reactive functional group covalently bonded to the surface. Mixing the covered n or p type silicon fine particles in an organic solvent to produce a first n or p type silicon fine particle paste;
P or n covered with an organic film containing a first reactive functional group covalently bonded to the surface and p or n type silicon fine particles covered with an organic film containing a second reactive functional group covalently bonded to the surface Forming a second p-type or n-type silicon fine particle paste by mixing type silicon fine particles in an organic solvent;
Mixing a first n or p-type silicon fine particle paste and a second p or n-type silicon fine particle paste to produce a third mixed paste containing p-type silicon fine particles and n-type silicon fine particles;
The three types of pastes are sequentially applied to the substrate surface in the first, third, second, or second, third, and first order, and the first reactive functional group and the second reactive functional group are applied. And a step of curing the group by reacting with each other.

A seventh invention is the manufacture of a solar cell and an optical sensor according to the sixth invention, wherein functional groups that react with each other are used as the first reactive functional group and the second reactive functional group, respectively. Is the method.

In an eighth aspect of the invention, an n or p-type silicon fine particle covered with an organic film containing a third reactive functional group covalently bonded to the surface and a crosslinking agent containing a plurality of fourth reactive functional groups in an organic solvent. Mixing to produce a fourth n-type silicon fine particle paste or a fifth p-type silicon fine particle paste;
Mixing the fourth n-type silicon fine particle paste and the fifth p-type silicon fine particle paste in an organic solvent to produce a sixth mixed paste containing n and p-type silicon fine particles;
The two kinds of pastes are sequentially applied to the substrate surface in the fourth, sixth, fifth, fifth, sixth, fourth order, and the third reactive functional group and the fourth reactive functional group. And a step of curing by reacting groups with each other.

According to a ninth aspect of the present invention, in the eighth aspect of the invention, a functional group that reacts with each other is used as the third reactive functional group and the fourth reactive functional group, respectively. It is.
Hereinafter, the gist of the present invention will be further described.

The present invention covers an n- or p-type silicon fine particle covered with an organic film containing a first reactive functional group covalently bonded to the surface and an organic film containing a second reactive functional group covalently bonded to the surface. Mixing n or p-type silicon fine particles in an organic solvent to produce a first n- or p-type silicon fine particle paste;
P or n covered with an organic film containing a first reactive functional group covalently bonded to the surface and p or n type silicon fine particles covered with an organic film containing a second reactive functional group covalently bonded to the surface Forming a second p-type or n-type silicon fine particle paste by mixing type silicon fine particles in an organic solvent;
Mixing a first n or p-type silicon fine particle paste and a second p or n-type silicon fine particle paste to produce a third mixed paste containing p-type silicon fine particles and n-type silicon fine particles;
The three types of pastes are sequentially applied to the substrate surface in the first, third, second, or second, third, and first order, and the first reactive functional group and the second reactive functional group are applied. Curing the groups by reacting with each other;
Alternatively, an n- or p-type silicon fine particle covered with an organic film containing a third reactive functional group covalently bonded to the surface and a cross-linking agent containing a plurality of fourth reactive functional groups are mixed in an organic solvent. Producing a fourth n-type silicon fine particle paste or a fifth p-type silicon fine particle paste;
Mixing the fourth n-type silicon fine particle paste and the fifth p-type silicon fine particle paste in an organic solvent to produce a sixth mixed paste containing n and p-type silicon fine particles;
The two kinds of pastes are sequentially applied to the substrate surface in the fourth, sixth, fifth, fifth, sixth, fourth order, and the third reactive functional group and the fourth reactive functional group. By reacting the groups with each other and curing,

N-type silicon covered with the organic thin film at least between an n-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface and a p-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface The gist is to provide a solar cell and an optical sensor in which a mixed layer of fine particles and p-type silicon fine particles covered with the organic thin film is formed.

Here, when the organic thin film covalently bonded to at least the surface is a monomolecular film, the internal resistance of the solar cell or the optical sensor can be advantageously reduced.
In addition, as the organic thin film covalently bonded to at least the surface, two kinds of thin films each containing the first reactive functional group or the second reactive functional group that react with each other are used, and each layer has the reactive functional group. It is convenient to provide a durable solar cell or photosensor when it is cured and formed into a layer by reaction between groups.

Alternatively, as the organic thin film covalently bonded to at least the surface, a thin film containing one kind of the third reactive functional group is used, and each layer has the fourth reactive functional group as the third reactive functional group. It is possible to provide a durable solar cell or a photosensor that is cured and formed into a layer by cross-linking with a cross-linking agent containing a plurality of.
Furthermore, if the mixed layer is made of silicon fine particles having different particle diameters, the junction area between p and n can be improved, which is advantageous in improving the conversion efficiency.

As described above, when a paste prepared using silicon fine particles coated with a reactive monomolecular film as in the present invention is used, an active layer (pn junction layer) can be formed by printing or an inkjet method. Therefore, there is an effect that it is possible to manufacture and provide solar cells and photosensors by an extremely low cost printing method. In addition, if p-type silicon fine particles and n-type silicon fine particles are mixed and used in the pn junction layer, the junction area between p and n can be greatly improved, and the conversion efficiency can be further improved.

(First embodiment)
The present invention covers an n- or p-type silicon fine particle covered with an organic film containing a first reactive functional group covalently bonded to the surface and an organic film containing a second reactive functional group covalently bonded to the surface. Mixing n or p-type silicon fine particles in an organic solvent to produce a first n- or p-type silicon fine particle paste;
P or n covered with an organic film containing a first reactive functional group covalently bonded to the surface and p or n type silicon fine particles covered with an organic film containing a second reactive functional group covalently bonded to the surface Forming a second p-type or n-type silicon fine particle paste by mixing type silicon fine particles in an organic solvent;
Mixing a first n or p-type silicon fine particle paste and a second p or n-type silicon fine particle paste to produce a third mixed paste containing p-type silicon fine particles and n-type silicon fine particles;
The three types of pastes are sequentially applied to the substrate surface in the first, third, second, or second, third, and first order, and the first reactive functional group and the second reactive functional group are applied. By reacting the groups with each other and curing,
N-type silicon covered with the organic thin film at least between an n-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface and a p-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface The present invention provides a solar cell and an optical sensor in which a pn fine particle mixed layer of fine particles and p-type silicon fine particles covered with the organic thin film is formed.

(Second Embodiment)
Further, the n- or p-type silicon fine particles covered with the organic film containing the third reactive functional group covalently bonded to the surface and the cross-linking agent containing the fourth reactive functional group are mixed in an organic solvent. Forming a n-type silicon fine particle paste or a fifth p-type silicon fine particle paste;
Mixing the fourth n-type silicon fine particle paste and the fifth p-type silicon fine particle paste in an organic solvent to produce a sixth mixed paste containing n and p-type silicon fine particles;
The two kinds of pastes are sequentially applied to the substrate surface in the fourth, sixth, fifth, fifth, sixth, fourth order, and the third reactive functional group and the fourth reactive functional group. By reacting the groups with each other and curing,
N-type silicon covered with the organic thin film at least between an n-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface and a p-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface The present invention provides a solar cell and an optical sensor in which a mixed layer of fine particles and p-type silicon fine particles covered with the organic thin film is formed.
Therefore, in the present invention, since the active layer can be applied and formed by printing or an ink jet method, there is an effect that it is possible to manufacture and provide solar cells and photosensors at a very low cost. Further, by using a layer (mixed layer) in which p-type silicon fine particles and n-type silicon fine particles are mixed in the pn junction layer, the junction area of p and n can be greatly improved, and the conversion efficiency can be further increased. There is an action that can be improved.

Hereinafter, although the detail of this invention is demonstrated using an Example, this invention is not limited at all by these Examples. In the present invention, since the solar cell and the optical sensor have the same structure, the solar cell manufacturing method will be described below as an example.

1. <Chemical adsorption solution preparation>
First, p-type silicon fine particles 1 having a particle size of about 100 to 10 nm were prepared and dried well. Next, as a chemical adsorbent, a functional group having a reactive functional group such as an epoxy group or imino group and an alkoxysilyl group at the other end, such as a chemical represented by the following formula (Chemical Formula 1) or (Chemical Formula 2) 99% by weight of a silanol condensation catalyst, for example, dibutyltin diacetylacetonate or acetic acid as an organic acid is weighed to 1% by weight, and a solvent in which the same amount of silicone and dimethylformamide are mixed, for example, hexamethyl A chemical adsorption solution was prepared by dissolving in a solution of 50% disiloxane and 50% dimethylformamide to a concentration of about 1% by weight (preferably the concentration of the chemical adsorbent is about 0.5 to 3%).

2. <Preparation of p-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group or an amino group>
The adsorbed liquid was mixed with the p-type silicon fine particles 1 and reacted for about 2 hours in normal air (relative humidity 45%). At this time, since many hydroxyl groups 2 are bonded to the dangling bonds on the surface of the p-type silicon fine particles 1 (FIG. 1a), the -Si (OCH ₃ ) group of the chemical adsorbent and the hydroxyl group are converted into a silanol condensation catalyst or In the presence of an organic acid, dealcoholization (in this case, de-CH ₃ OH) is carried out to form a bond as shown in the following formula (Chemical Formula 3) or (Chemical Formula 4), and the surface of the silicon fine particle surface is chemically bonded to the surface. A chemisorption monomolecular film 3 containing bonded epoxy groups or a chemisorption film 4 containing amino groups was formed with a thickness of about 1 nanometer (FIGS. 1b and 1c).

Here, when an adsorbent containing an amino group is used, since a precipitate is generated with a tin-based catalyst, it is better to use an organic acid such as acetic acid. The amino group contains an imino group, but substances containing an imino group in addition to the amino group include pyrrole derivatives and imidazole derivatives. Furthermore, when a ketimine derivative was used, an amino group could be easily introduced by hydrolysis after film formation.
Thereafter, by adding a chlorinated solvent such as trichlene and washing with stirring, p-type silicon fine particles 5 and 6 covered with a chemisorption monomolecular film having a reactive functional group such as an epoxy group or an amino group on the surface are produced. did it.

In addition, since the formed film was extremely thin with a nanometer level film thickness, the particle diameter was not impaired. Further, since this withstand voltage was 0.1 V or less, this film had almost no electrical insulation function and had a function of preventing the progress of silicon oxidation.

At this time, if the amount of adsorbent molecules with respect to the fine particles is adjusted to an appropriate amount, even if the adsorbent molecules are taken out into the air without being washed, the reactivity does not substantially change, and the chemical adsorbent that the solvent has evaporated and remains on the particle surface Reacted with moisture in the air on the particle surface to obtain silicon fine particles in which an ultrathin polymer film made of the chemical adsorbent was formed on the particle surface.

Moreover, since this method is a dealcoholization reaction, it does not require a dry atmosphere and is excellent in mass productivity.

3. <Preparation of paste containing p-type silicon fine particles>
Next, the p-type silicon fine particles 5 and 6 covered with the chemisorption monomolecular film having the epoxy group or amino group were taken to the same extent and mixed sufficiently in isopropyl alcohol to form p-type silicon fine particles into a paste.

4). <Preparation of n-type silicon fine particle paste covered with chemisorption monomolecular film having epoxy group or amino group>
In the same manner as described above, a chemisorption monomolecular film having an epoxy group or an amino group is formed on each n-type silicon fine particle, and the n-type silicon fine particle covered with the epoxy group and the n-type silicon fine particle covered with the amino group The same amount was taken and mixed well in isopropyl alcohol to prepare an n-type silicon fine particle paste.

5). <Create mixed paste>
The same amount of the p-type silicon fine particle paste and n-type silicon fine particle paste obtained by the above-mentioned process were taken and mixed well to prepare a mixed paste containing p-type silicon fine particles and n-type silicon fine particles.
At this time, the composition of the p-type silicon fine particle paste and the n-type silicon fine particle paste may be changed as necessary. Further, p-type silicon fine particle paste and n-type silicon fine particles having different particle diameters may be used.

6). <Manufacture of solar cells 1>
As shown in FIG. 2, an n-type silicon fine particle paste was applied on the ITO transparent electrode 12 formed on the surface of the glass substrate 11 in advance (screen printing, ink jet printing, or the like could be used as the coating method). When heated to about 50 to 100 ° C., an epoxy group and an amino group are added by the reaction shown in the following formula (Chemical Formula 5), and the silicon fine particles are cured without containing a binder, and the film thickness is 5 A coating film 13 of n-type silicon fine particles of about micron could be formed.

Next, a mixed paste containing p-type silicon fine particles and n-type silicon fine particles mixed in the same manner as described above is applied onto the coating film 13 and heated to about 50 to 100 ° C. to be cured. A mixed layer 14 in which p-type silicon fine particles and n-type silicon fine particles having a thickness of about 10 microns were mixed was formed.
Further, the p-type silicon fine particle paste obtained in Example 1 is applied on the coating film 14 and heated to about 150 ° C. to form a coating film 15 of p-type silicon fine particles having a thickness of about 5 microns. The whole was completely cured.

Finally, when the silver paste was printed to form the back electrode 16, a solar cell 18 having a light incident direction of 17 could be manufactured.
Here, 19, 20, 21 and 22 are n-type silicon fine particles covered with a chemisorption monomolecular film having an amino group, n-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group, and amino These are p-type silicon fine particles covered with a chemical adsorption monomolecular film having a group and p-type silicon fine particles covered with a chemical adsorption monomolecular film having an epoxy group.

At this time, if the monomolecular films 23 and 24 having an epoxy group or an amino group are formed in advance on the surface of the ITO transparent electrode 12 by the same method, the monomolecular film on the surface of the silicon fine particles becomes the ITO transparent electrode. By reacting with the monomolecular film on the 15 surface, a silicon solar cell having high peel strength could be produced. (Figure 2)

When such an intermediate mixed layer is introduced, the pn junction area can be greatly improved, and the conversion efficiency as a solar cell is more than twice the conversion efficiency of the solar cell when no mixed layer is formed. About 12% was achieved. In addition, the reactive monomolecular film on the surface of the p-type and n-type silicon fine particles functions to cure and form silicon fine particles and to prevent oxidation of the p-type and n-type silicon fine particles in the air.

Furthermore, since this reactive monomolecular film has a thickness of about 1 nm, it hardly interferes with silicon conduction.
Furthermore, by controlling the particle size of the silicon fine particles between 100 μm and 1 nm, the absorption wavelength range can be controlled from infrared light to ultraviolet light.

11. <Adjustment of chemical adsorption solution>
As shown in FIG. 3, p-type silicon fine particles 31 (particle diameter 20 nm) were prepared, washed thoroughly and dried.
Next, 0.99 parts by weight of 3-glycidoxypropyltrimethoxysilane (Chemical Formula 1, manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.01 parts by weight of dibutyltin bisacetylacetonate (condensation catalyst) were weighed. A chemical adsorption solution was prepared by dissolving in 100 parts by weight of hexamethyldisiloxane solvent.

12 <Preparation of p-type silicon fine particles covered with a chemisorption monomolecular film having a poxy group>
The p-type silicon fine particles 31 were dispersed in the thus obtained chemical adsorption solution, and reacted with the hydroxyl groups 32 on the surface in the air (relative humidity 45%) for about 2 hours while stirring.

Thereafter, the p-type silicon fine particles 34 covered with a chemisorption monomolecular film 33 having an epoxy group (indicated by E in the figure) are prepared by washing with chloroform to remove excess alkoxysilane compound and dibutyltin bisacetylacetonate. did.
At this time, since the thickness of the monomolecular film was about 1 nm, the conductivity of silicon was not impaired, and the oxidation resistance of the obtained epoxidized p-type silicon fine particles was improved. .

13. <Preparation of paste containing p-type silicon fine particles>
100 parts by weight of p-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group obtained in 12 and 7 parts by weight of a crosslinkable polyfunctional 2-methylimidazole were added as a crosslinking agent, A paste containing p-type silicon fine particles was prepared by sufficiently mixing 40 parts by weight of isopropyl alcohol.

14 <Preparation of n-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group>
12. Using n-type silicon fine particles (particle size 10 to 100 nm), In the same manner as in the above step, n-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group were prepared.

15. <Preparation of paste containing n-type silicon fine particles>
14 100 parts by weight of n-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group obtained in the above and crosslinkable 2-methylimidazole (in addition, polyfunctional substances such as triazine thiol could be used). 7 parts by weight was added as a crosslinking agent and mixed with 40 parts by weight of isopropyl alcohol. A paste containing n-type silicon fine particles was prepared.

16. <Create mixed paste>
13. The above-mentioned 13. And 15. The same amount of the p-type silicon fine particle paste and the n-type silicon fine particle paste obtained by the above process were taken and mixed sufficiently to prepare a mixed paste containing p-type silicon fine particles and n-type silicon fine particles.
At this time, there was no problem even if the compositions of the p-type silicon fine particle paste and the n-type silicon fine particle paste were slightly changed as required. On the other hand, when p-type silicon fine particle paste and n-type silicon fine particle paste having different particle diameters were used, a solar cell with higher power generation efficiency was obtained as compared with the case of using the same particle diameter.

17. <Production of ITO glass plate covered with chemisorption monomolecular film having epoxy group>
As shown in FIG. 4, a glass plate 36 with an ITO transparent electrode 35 was prepared, washed thoroughly and dried.
On the other hand, 0.99 parts by weight of 3-glycidoxypropyltrimethoxysilane (Chemical Formula 11) and 0.01 parts by weight of dibutyltin bisacetylacetonate (condensation catalyst) were weighed, and this was added to 100 parts by weight of hexamethyldisiloxane. A chemical adsorption solution was prepared by dissolving in a solvent.

Next, the chemical adsorption solution was applied to the surface of the ITO glass plate on the side of the ITO electrode 35 and reacted in air (relative humidity 45%) for about 2 hours.
Then, it washed with chloroform, the excess alkoxysilane compound and dibutyltin bisacetylacetonate were removed, and the glass plate 36 with the ITO transparent electrode 35 covered with the chemical adsorption monomolecular film 37 which has an epoxy group was produced.

18. <Manufacture of solar cells 2>
Next, the n-type silicon fine particle paste obtained by the above process is applied to the surface of the glass plate 36 with the ITO transparent electrode 35 covered with the chemical adsorption monomolecular film having an epoxy group, and about 50 to 100 ° C. When heated to a cross-linking reaction as shown in the following chemical formula (Chemical Formula 6),
An epoxy group and an imino group were bonded, and the silicon fine particles were cured without containing a binder, and a coating film 38 of n-type silicon fine particles having a film thickness of about 5 microns could be formed.

In addition, The mixed paste containing the p-type silicon fine particles and the n-type silicon fine particles obtained by the above process is applied, heated to about 50 to 100 ° C. and cured in the same manner, coating the mixed layer 3 9 including an n-type silicon microparticles was formed.

Further, on the coating film 3 9, 13. The p-type silicon fine particle paste obtained by the above process was applied, heated to about 150 ° C. to form a coating film 40 of p-type silicon fine particles having a thickness of about 5 microns, and the whole was completely cured.
Finally, when the back electrode 41 was formed by evaporating Al, the solar cell 43 with the light incident direction 42 could be manufactured.

    Here, 44 and 45 are n-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group and p-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group, respectively. Reference numeral 46 denotes a crosslinked site after curing.

Also in this example, when the intermediate mixed layer is introduced, the pn junction area can be greatly improved, and the conversion efficiency as the solar cell is 2 of the conversion efficiency of the solar cell when the mixed layer is not formed. More than doubled, about 11% was achieved. In addition, the reactive monomolecular film and the cross-linking agent on the surface of the p-type and n-type silicon fine particles function to cure the silicon fine particles and prevent the oxidation of the p-type and n-type silicon fine particles in the air. did.
Furthermore, since this reactive monomolecular film has a thickness of about 1 nm, it hardly interferes with silicon conduction.
Furthermore, by controlling the particle diameter of the silicon fine particles between 100 μm and 4 nm, the absorption wavelength range can be controlled from infrared light to ultraviolet light.

In Example 1, the substance represented by the formula (Chemical Formula 1) or (Chemical Formula 2) was used as the chemical adsorbent containing a reactive group, but in addition to the above, the following (1) to (16) The materials shown in the above were available.
(1) (CH ₂ OCH) CH ₂ O (CH ₂ ) ₇ Si (OCH ₃ ) ₃
(2) (CH ₂ OCH) CH ₂ O (CH ₂ ) ₁₁ Si (OCH ₃ ) ₃
(3) (CH ₂ CHOCH (CH ₂ ) ₂ ) CH (CH ₂ ) ₂ Si (OCH ₃ ) _{3
(4) (CH 2 CHOCH (} CH 2) 2) CH (CH 2) 4 Si (OCH 3) 3
_{(5) (CH 2 CHOCH (} CH 2) 2) CH (CH 2) 6 Si (OCH 3) 3
_{(6) (CH 2 OCH)} CH 2 O (CH 2) 7 Si (OC 2 H 5) 3
(7) (CH ₂ OCH) CH ₂ O (CH ₂ ) ₁₁ Si (OC ₂ H ₅ ) _{3
(8) (CH 2 CHOCH (} CH 2) 2) CH (CH 2) 2 Si (OC 2 H 5) 3
_{(9) (CH 2 CHOCH (} CH 2) 2) CH (CH 2) 4 Si (OC 2 H 5) 3
(10) (CH ₂ CHOCH (CH ₂ ) ₂ ) CH (CH ₂ ) ₆ Si (OC ₂ H ₅ ) ₃
(11) H ₂ N (CH ₂ ) ₅ Si (OCH ₃ ) ₃
(12) H ₂ N (CH ₂ ) ₇ Si (OCH ₃ ) ₃
(13) H ₂ N (CH ₂ ) ₉ Si (OCH ₃ ) ₃
(14) H ₂ N (CH ₂ ) ₅ Si (OC ₂ H ₅ ) ₃
(15) H ₂ N (CH ₂ ) ₇ Si (OC ₂ H ₅ ) ₃
(16) H ₂ N (CH ₂ ) ₉ Si (OC ₂ H ₅ ) ₃

Here, the (CH ₂ OCH) — group represents a functional group represented by the following formula (Chemical Formula 7), and the (CH ₂ CHOCH (CH ₂ ) ₂ ) CH— group is represented by the following formula (Chemical Formula 8). Represents a functional group.

Furthermore, the substances shown in the following (17) to (22) can be used as chemical adsorbents containing energy beam reactive functional groups such as light or electron beams. In this case, it is only necessary to irradiate an energy beam such as light or an electron beam for curing.
(17) CH≡C—C≡C— (CH ₂ ) ₁₅ SiCl ₃
(18) CH≡C—C≡C— (CH ₂ ) ₂ Si (CH ₃ ) ₂ (CH ₂ ) ₁₅ SiCl ₃
(19) CH≡C—C≡C— (CH ₂ ) ₂ Si (CH ₃ ) ₂ (CH ₂ ) ₉ SiCl _{3
(20) (C 6 H 5} ) (CH) 2 CO (C 6 H 4) O (CH 2) 6 OSi (OCH 3) 3
_{(21) (C 6 H 5} ) (CH) 2 CO (C 6 H 4) O (CH 2) 6 OSi (OC 2 H 5) 3
_{(22) (C 6 H 5} ) CO (CH) 2 (C 6 H 4) O (CH 2) 6 OSi (OCH 3) 3
_{Here, (C 6 H 5) CO} (CH) 2 (C 6 H 4) - represents a chalconyl group.

In Example 1, as the silanol condensation catalyst, carboxylic acid metal salt, carboxylic acid ester metal salt, carboxylic acid metal salt polymer, carboxylic acid metal salt chelate, titanate ester and titanate ester chelate can be used. It is. More specifically, stannous acetate, dibutyltin dilaurate, dibutyltin dioctate, dibutyltin diacetate, dioctyltin dilaurate, dioctyltin dioctate, dioctyltin diacetate, stannous dioctanoate, lead naphthenate, cobalt naphthenate , Iron 2-ethylhexenoate, dioctyltin bisoctylthioglycolate, dioctyltin maleate, dibutyltin maleate polymer, dimethyltin mercaptopropionate polymer, dibutyltin bisacetylacetate, dioctyltin bisacetyl Laurate, tetrabutyl titanate, tetranonyl titanate and bis (acetylacetonyl) dipropyl titanate could be used.

In addition, as a solvent for the film-forming solution, the chemical adsorbent is an alkoxysilane-based solvent, a chlorosilane-based solvent, an organic chlorine-based solvent that does not contain water in any case, a hydrocarbon-based solvent, a fluorocarbon-based solvent, a silicone-based solvent, Alternatively, it was possible to use a mixture thereof. In addition, when it is going to raise particle concentration by evaporating a solvent, without wash | cleaning, the boiling point of a solvent is good at about 50-250 degreeC.

Specifically usable are organic chlorinated solvents, non-aqueous petroleum naphtha, solvent naphtha, petroleum ether, petroleum benzine, isoparaffin, normal paraffin, decalin, industrial gasoline, nonane, decane, kerosene, dimethyl silicone, phenyl silicone , Alkyl-modified silicone, polyether silicone, dimethylformamide and the like. Further, when the adsorbent is an alkoxysilane type and the organic film is formed by evaporating the solvent, an alcohol type solvent such as methanol, ethanol, propanol, or a mixture thereof can be used in addition to the solvent.

Fluorocarbon solvents include fluorocarbon solvents, Fluorinert (product of 3M), Afludo (product of Asahi Glass). In addition, these may be used individually by 1 type and may mix 2 or more types as long as it mixes well. Further, an organic chlorine solvent such as chloroform may be added.

On the other hand, when a ketimine compound or organic acid, aldimine compound, enamine compound, oxazolidine compound, aminoalkylalkoxysilane compound is used instead of the above-mentioned silanol condensation catalyst, the treatment time is about 1/2 to 2/3 even at the same concentration. It was able to shorten to.

Furthermore, a silanol condensation catalyst and a ketimine compound, or an organic acid, an aldimine compound, an enamine compound, an oxazolidine compound, and an aminoalkylalkoxysilane compound can be used in a range of 1: 9 to 9: 1. )), The processing time can be further several times faster (up to about 30 minutes), and the film forming time can be reduced to a fraction of a minute.

For example, dibutyltin oxide, which is a silanol catalyst, was replaced with H3 from Japan Epoxy Resin, which is a ketimine compound, and the other conditions were the same, but the reaction time was reduced to about 1 hour. Results were obtained.

Furthermore, the silanol catalyst was replaced with a mixture of ketimine compound Japan Epoxy Resin H3 and silanol catalyst dibutyltin bisacetylacetonate (mixing ratio is 1: 1), and other conditions were the same. The same results were obtained except that the reaction time could be shortened to about 30 minutes.

Therefore, the above results revealed that ketimine compounds, organic acids, aldimine compounds, enamine compounds, oxazolidine compounds, and aminoalkylalkoxysilane compounds are more active than silanol condensation catalysts.

Furthermore, it was confirmed that the activity was further increased when one of a ketimine compound, organic acid, aldimine compound, enamine compound, oxazolidine compound, and aminoalkylalkoxysilane compound was mixed with a silanol condensation catalyst.

Here, the ketimine compound that can be used is not particularly limited. For example, 2,5,8-triaza-1,8-nonadiene, 3,11-dimethyl-4,7,10-triaza-3 , 10-tridecadiene, 2,10-dimethyl-3,6,9-triaza-2,9-undecadiene, 2,4,12,14-tetramethyl-5,8,11-triaza-4,11-pentadeca Diene, 2,4,15,17-tetramethyl-5,8,11,14-tetraaza-4,14-octadecadiene, 2,4,20,22-tetramethyl-5,12,19-triaza- 4,19-trieicosadiene and the like.

Further, the organic acid that can be used is not particularly limited, but there are, for example, formic acid, acetic acid, propionic acid, lactic acid, malonic acid, and the like, which have almost the same effects.

In the above two embodiments, silicon fine particles have been described as an example. However, the present invention is applicable to any semiconductor fine particles as long as the surface is a semiconductor fine particle containing active hydrogen such as hydrogen of a hydroxyl group. Since it is possible, it can be used for various printing type solar cells and sensors. .

It is the conceptual diagram which expanded the reaction of the silicon fine particle surface in the 1st Example of this invention to the molecular level, (a) is the figure of the silicon fine particle surface before reaction, (b) is the monomolecular film containing an epoxy group (C) shows a diagram after a monomolecular film containing an amino group is formed.

The solar cell cross-sectional conceptual diagram using the silicon fine particle in the 1st Example of this invention is shown.

It is the conceptual diagram which expanded the reaction of the silicon fine particle surface in the 2nd Example of this invention to the molecular level, (a) is the figure of the silicon fine particle surface before reaction, (b) is the monomolecular film containing an epoxy group The figure after (c) is formed, conceptually showing silicon fine particles whose entire surface is covered with an epoxy group.

The cross-sectional conceptual diagram of the solar cell using the silicon fine particle in the 2nd Example of this invention is shown.

Explanation of symbols

1 n-type silicon fine particle 2 hydroxyl group 3 chemisorption monomolecular film containing epoxy group 4 chemisorption film containing amino group
N-type silicon microparticles covered with a chemisorption monomolecular film having 5 epoxy groups
N-type silicon fine particles covered with chemisorption monomolecular film having 6 amino groups 11 glass substrate 12 ITO transparent electrode n-type silicon fine particles covered with epoxy group
13 n-type silicon fine particles coated with amino groups
14 Mixed coating film of n-type and p-type silicon fine particles
15 Coating film of p-type silicon fine particles 16 Back electrode 17 Light incident direction
Solar cell using 18 fine particles 19, 20 n-type silicon fine particles 21, 22 p-type silicon fine particles 31 n-type silicon fine particles 32 hydroxyl groups 33 Chemically adsorbed monomolecular film containing an epoxy group (E represents an epoxy group)
34 n-type silicon fine particles covered with a chemisorption monomolecular film having an epoxy group 35 ITO transparent electrode 36 Glass plate 36
Chemisorbed monolayer with 37 epoxy groups
38 Coating film of n-type silicon fine particles
39 Coating film of p-type silicon fine particles 40 Coating film comprising a mixed layer in which p-type and n-type silicon fine particles are mixed 41 Back electrode
42 Light incident direction 43 Solar cell using fine particles 44 n-type silicon fine particles 45 p-type silicon fine particles 46 Cross-linking sites

Claims (9)

N-type silicon covered with the organic thin film at least between an n-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface and a p-type silicon fine particle layer covered with an organic thin film covalently bonded to the surface A solar cell and an optical sensor, wherein a mixed layer of fine particles and pn fine particles of p-type silicon fine particles covered with the organic thin film is formed. The solar cell and photosensor according to claim 1, wherein at least the organic thin film covalently bonded to the surface is a monomolecular film. At least two types of thin films each containing a functional group that reacts with each other are used as the organic thin film covalently bonded to the surface, and each layer is cured and formed into a layer by reaction between the reactive functional groups. The solar cell and the optical sensor according to claim 1, wherein the solar cell is an optical sensor. At least a thin film containing one kind of reactive functional group is used as the organic thin film covalently bonded to the surface, and each layer is cured and formed into a layer by crosslinking the reactive functional group with a crosslinking agent. The solar cell and the optical sensor according to claim 1, wherein the solar cell is an optical sensor. The solar cell and the optical sensor according to claim 1, wherein the mixed layer is formed using silicon fine particles having different particle diameters. N or p covered with an organic film containing a first reactive functional group covalently bonded to the surface and n or p-type silicon fine particles covered with an organic film containing a second reactive functional group covalently bonded to the surface Forming a first n-type or p-type silicon fine particle paste by mixing type silicon fine particles in an organic solvent;
P or n covered with an organic film containing a first reactive functional group covalently bonded to the surface and p or n type silicon fine particles covered with an organic film containing a second reactive functional group covalently bonded to the surface Forming a second p-type or n-type silicon fine particle paste by mixing type silicon fine particles in an organic solvent;
Mixing a first n or p-type silicon fine particle paste and a second p or n-type silicon fine particle paste to produce a third mixed paste containing p-type silicon fine particles and n-type silicon fine particles;
The three types of pastes are sequentially applied to the substrate surface in the first, third, second, or second, third, and first order, and the first reactive functional group and the second reactive functional group are applied. And a step of curing the group by reacting with each other, and a method for producing a solar cell and an optical sensor. The method for manufacturing a solar cell and an optical sensor according to claim 6, wherein functional groups that react with each other are used as the first reactive functional group and the second reactive functional group, respectively. An n- or p-type silicon fine particle covered with an organic film containing a third reactive functional group covalently bonded to the surface and a crosslinking agent containing a plurality of fourth reactive functional groups are mixed in an organic solvent to form a fourth. Forming a n-type silicon fine particle paste or a fifth p-type silicon fine particle paste;
Mixing the fourth n-type silicon fine particle paste and the fifth p-type silicon fine particle paste to produce a sixth mixed paste containing n and p-type silicon fine particles;
The two kinds of pastes are sequentially applied to the substrate surface in the fourth, sixth, fifth, fifth, sixth, fourth order, and the third reactive functional group and the fourth reactive functional group. And a step of curing by reacting groups with each other, and a method for producing a solar cell and a photosensor. 9. The method for manufacturing a solar cell and an optical sensor according to claim 8, wherein functional groups that react with each other are used as the third reactive functional group and the fourth reactive functional group, respectively.

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