JP2000307141A - Functional part and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a bulge from being generated in a plasma CVD film forming region on an organic flexible substrate by a method wherein a functional part with a plasma CVD film is provided on an inorganic insulating layer on the organic flexible substrate. SOLUTION: An inorganic insulating layer 3, a lower electrode 4, a photoelectric conversion layer 5, and an upper electrode 6 are formed in this sequence on an organic flexible substrate 2 for the formation of a solar cell. It is preferable that the inorganic insulating layer 3 contains at least an element selected out of Si and Al and another element selected from oxygen, nitrogen, and carbon. It is preferable that the inorganic insulating layer is formed as thick as 0.7 to 1 μm. Light is incident on the front surface of the organic flexible substrate 2, so that the lower electrode 4 is usually formed of metal. The photoelectric conversion layer 5 is formed of a plasma CVD film, and the plasma CVD film may be amorphous or fine crystalline. The photoelectric conversion layer 5 is formed of a single crystal silicon, a fine crystal silicon or an amorphous silicon possessed of a pn junction or a pin junction, preferably a pin junction. The upper electrode 6 is formed of transparent conductive material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a plasma C on a flexible organic flexible substrate.
The present invention relates to a functional component having a VD film and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, an organic flexible substrate is used in a thin film laminated device such as a solar cell. Since the organic flexible substrate has flexibility and can be wound up and developed, it has the following advantages in production. When manufacturing a thin film laminated device, a step of laminating many functional thin films by a vacuum process, a step of patterning wiring electrodes, interlayer insulating films and the like by a screen printing method or the like to form them on the surface of the functional thin film, A step of providing a protective layer on the outermost surface of the multilayer device is provided. In each of these steps, if a long organic flexible substrate is used in a roll-to-roll manner, that is, the substrate is wound, and the functional thin film, electrode, and insulating film are formed on the substrate while being fed and wound. By forming the above, the tact time can be reduced, and it is not necessary to carry the substrate,
There is an effect that the handling of the substrate becomes easy, and the throughput can be improved. Similar effects can be obtained even when the degree of integration of the thin film stacked device is improved and large-scale mass production is attempted.

[0003]

In a solar cell, a photoelectric conversion layer containing Si as a main component is usually provided on an organic flexible substrate. This photoelectric conversion layer is generally formed by a plasma CVD method. In the plasma CVD method, a substrate temperature is set to 160 to form a high-performance thin film.
It is necessary to raise to about 200 ° C. Since the organic flexible substrate and the photoelectric conversion layer, which is an inorganic film, have different thermal expansion coefficients, the thermal shrinkage in the cooling process after film formation is different.
Therefore, if patterning is performed using a mask when the photoelectric conversion layer is formed by plasma CVD, the organic flexible substrate slides and deforms in the photoelectric conversion layer formation region, and the organic flexible substrate in the patterning portion (plasma CVD film formation region) It rises like a drum. Such swelling tends to be more remarkable when a polymer material having a glass transition point (Tg) is used for the substrate.

When a bulge occurs in a patterning portion, it becomes difficult to perform positioning during patterning using a mask, so that it is difficult to form a multilayered patterning film. In addition, there is also an aesthetic problem that the appearance is poor when applied to a clock or a remote control when there is a climax. If a plasma CVD film is formed on the entire surface of the substrate without performing patterning, such a problem can be avoided.
In that case, a plasma CVD film is formed up to an unnecessary region, which leads to an increase in cost. Further, when the film is formed on the entire surface, it is necessary to perform patterning by laser processing or the like after the formation of the plasma CVD film. Processing costs increase.

SUMMARY OF THE INVENTION It is an object of the present invention to suppress a rise of an organic flexible substrate in a plasma CVD film forming region in a functional component having a plasma CVD film formed by mask formation on an organic flexible substrate.

[0006]

The above object is achieved by the following (1).
This is achieved by the present invention according to (10). (1) having an inorganic insulating layer on an organic flexible substrate,
A functional component having a plasma CVD film on the inorganic insulating layer. (2) The functional component according to the above (1), wherein the plasma CVD film is patterned using a mask. (3) The functional component according to the above (1) or (2), wherein the thickness of the inorganic insulating layer is 50 nm to 10 μm. (4) The sheet resistance of the inorganic insulating layer is 100 kΩ / □
The functional component according to any one of (1) to (3) above. (5) The above (1), wherein the inorganic insulating layer contains at least one of Si and Al and at least one of oxygen, nitrogen and carbon, or contains diamond-like carbon.
To (4). (6) The functional component according to any one of (1) to (5), wherein the plasma CVD film contains silicon. (7) The functional component according to any one of (1) to (6), wherein the organic flexible substrate is made of polyethylene naphthalate, polyether sulfone, polyimide, polyamide, or polyimide amide. (8) A method for producing a functional component, comprising the steps of: forming an inorganic insulating layer on the entire surface of an organic flexible substrate; and patterning the inorganic insulating layer with a mask using a mask to laminate a plasma CVD film. (9) The method for producing a functional component according to the above (8), wherein a plasma beam method is used for forming the inorganic insulating layer. (10) The method for producing a functional component according to the above (8) or (9), wherein the functional component according to any one of the above (1) to (7) is obtained.

[0007]

Function and Effect The functional component of the present invention has an inorganic insulating layer on an organic flexible substrate, and has a plasma CVD film on the inorganic insulating layer.

By forming an inorganic insulating layer on the organic flexible substrate, preferably on the entire surface thereof, it is possible to suppress the above-mentioned swelling of the patterned portion. As a result, even when patterning using a mask is used, the plasma CVD film can be multi-layered, and the appearance of the functional component is improved, and the design is improved.

The effect of the present invention is realized by interposing an inorganic insulating layer between the organic flexible substrate and the plasma CVD film. Therefore, it is not necessary to form an inorganic insulating layer on the opposite surface of the organic flexible substrate, that is, on the surface on which the plasma CVD film is not formed. However, when an inorganic insulating layer is formed on an organic flexible substrate, the edge of the substrate (four sides of the substrate) may be bent and curling may occur. In addition, oligomers may be deposited on the exposed surface (the opposite surface) of the organic flexible substrate due to heating during the formation of the plasma CVD film. A model number or the like is often printed on the opposite surface of the substrate. However, if the oligomer is deposited, the adhesion of the ink is reduced, which is not preferable. In order to prevent such a phenomenon, it is preferable to form an inorganic insulating layer on the opposite surface of the substrate.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a partial sectional view showing an example of the structure of a solar cell which is an example of a functional component according to the present invention. The solar cell shown in FIG. 1 includes an inorganic insulating layer 3, a lower electrode 4, a photoelectric conversion layer 5, and an upper electrode 6 on an organic flexible substrate 2.
In this order.

The illustrated solar cell has a configuration in which a plurality of solar cells each having a light receiving surface are connected in series.
A collection / wiring electrode 11 is provided on the upper electrode 6 of each cell. The illustrated collecting / wiring electrode 11 is a connecting portion between the collecting electrode and the wiring electrode. The collecting electrode is an electrode for collecting the electric power generated in each cell from the surface of the upper electrode 6 having a relatively high specific resistance. The wiring electrode is an electrode for connecting the collection electrode of each cell to the lower electrode of an adjacent cell. In the illustrated example, the collecting / wiring electrode 11
, A connection conductor 12 extends through the upper electrode 6 and the photoelectric conversion layer 5 and is connected to the lower electrode 4 of an adjacent cell, whereby the adjacent cells are connected in series. An interlayer insulating layer 9 exists at a part between the upper electrode 6 and the photoelectric conversion layer 5, and the upper electrode 6
The separator insulating layer 10 exists between the two. In the illustrated example, the separator portion 101 of the separator insulating layer 10 extends through the upper electrode 6, the photoelectric conversion layer 5, and the lower electrode 4, and insulates the lower electrodes of adjacent cells. The separator part 101 is a wall-shaped body that also extends in the depth direction in the figure.

Although not shown, a positive electrode and a negative electrode are provided at both ends of the series connection.

Although not shown, a sealing member is preferably provided at least on the surface of the illustrated solar cell where the upper electrode 6 is formed, in order to suppress mechanical damage, oxidation, corrosion and the like of the solar cell. Further, such a sealing member is preferably provided also on the back surface side of the substrate 2.

Hereinafter, the configuration of each unit will be described in detail.

Organic Flexible Substrate The organic flexible substrate 2 only needs to have flexibility.
The constituent material is not particularly limited, but preferably, polyethylene naphthalate (PEN), polyether sulfone (PES), polyimide, polyamide, or polyimide amide is used, and particularly, PEN or PES is preferably used. These include heat resistance during plasma CVD film formation, heat resistance during long-term use, Young's modulus (stiffness),
It has excellent performance in terms of mechanical properties and the like. PEN and PES are also excellent in transparency. In addition to these, for example, polyarylate is also preferable.

When the present invention is applied to a solar cell having a configuration in which light is incident from the organic flexible substrate side, the organic flexible substrate needs to have translucency. In this case, the light transmittance of the organic flexible substrate at a wavelength of 550 nm is preferably 85% or more, more preferably 90% or more.
% Or more.

The melting point of the organic flexible substrate is preferably 260 ° C. or higher, and the upper limit is not particularly limited, but is usually about 330 ° C. The glass transition point of the organic flexible substrate is preferably 70 ° C. or higher, particularly preferably 100 ° C. or higher. The upper limit is not particularly limited, but is usually about 115 ° C. It is not necessary to have a glass transition point like polyimide. Further, the heat resistant temperature or the continuous use temperature is preferably 130 ° C. or more, particularly preferably 160 ° C. or more, and the upper limit is not particularly limited, but is usually about 210 ° C.

The thickness of the organic flexible substrate may be appropriately determined according to the required strength, bending rigidity and the like, but is usually preferably from 25 to 100 μm. If the substrate is too thin, handling becomes difficult, and defective products due to breakage of the substrate may occur. On the other hand, when the substrate is too thick, the amount of light transmission is reduced when light is incident through the substrate, and the solar cell characteristics deteriorate.

MOR (Molecula) of an organic flexible substrate
r Orientation Ratio) is preferably 1.0 to 3.
0, more preferably 1.0 to 2.0, especially 1.0 to 1.
8 is preferred. MOR is a value serving as an index of molecular orientation, and if the MOR is within the above range, the organic flexible substrate is less likely to be deformed. For MOR, see, for example, Compartec 1998.3, “Quality Control of Films and Sheets Applying Microwave Molecular Orientation Meter,” Shigeyoshi Ohsaki, Seikei
-Kakou Vol.7 No.11 1995 "Molecular orientation behavior with biaxial extension" is described in the literature of Yasunobu Zushi, Takahiro Niwa, Sadao Hibiki, Shinichi Nagata, Tachi, etc. The larger the MOR is, the larger the anisotropy is. When the MOR is 1.0, the MOR is not oriented and is random. MO of organic flexible substrate
If R is in the above range, that is, if the anisotropy is small,
Since the difference in the amount of expansion and contraction depending on the direction is reduced, the displacement of the thin film formed on the substrate can be reduced.

The MOR may vary depending on the position in one resin film. In particular, in a resin film manufactured by using the biaxial stretching method, the degree of orientation tends to increase near the end portion gripped during the stretching.
Therefore, even if the resin is generally excellent in the degree of molecular orientation, it is preferable to use the resin after examining the degree of molecular orientation for each part of the resin film to be used and confirming that the degree of orientation is within the above degree of orientation. .

The MOR can be determined, for example, by measuring the transmitted microwave intensity while rotating the sample. Since the interaction between the microwave electric field of a certain frequency and the dipole that constitutes the polymer substance is related to the inner product of the two vectors, rotating the sample in the microwave polarized electric field causes the dielectric constant to increase. The intensity of the transmitted microwave changes due to the anisotropy, and as a result, the degree of molecular orientation can be known. The frequency of the microwave used for the measurement is not particularly limited, but is usually 4 GHz or 12 GHz. As a measuring instrument to which such a principle is applied, for example, a molecular orientation meter MOA-5001A, 5012 manufactured by Shin-Oji Paper Co., Ltd.
A, 3001A and 3012A. Also, MOR
Can also be determined by an X-ray diffraction method, an infrared dichroism method, a polarization fluorescence method, an ultrasonic method, an optical method, an NMR method, or the like.

Inorganic Insulating Layer The inorganic insulating layer preferably contains at least one kind of Si and Al and at least one kind of oxygen, nitrogen and carbon, especially silicon oxide, silicon nitride, silicon carbide and aluminum oxide. It is preferable to contain at least one of the following. The inorganic insulating layer having such a composition,
It is inexpensive, and if these are used, the effects of the present invention are sufficiently realized. These compounds are usually present in a stoichiometric composition in the inorganic insulating layer, but may be slightly biased. When two or more of these compounds are used in combination,
The ratio is arbitrary.

The thickness of the inorganic insulating layer is preferably from 50 nm to
It is 10 μm, more preferably 300 nm to 10 μm, and still more preferably 0.7 to 1 μm. If the inorganic insulating layer is too thin, the effect of the present invention of suppressing the drum-shaped swelling of the patterning portion becomes insufficient. On the other hand, if the inorganic insulating layer is too thick, cracks occur in the inorganic insulating layer,
The inorganic insulating layer is easily separated from the organic flexible substrate. Further, in the case where light is incident through the organic flexible substrate, if the inorganic insulating layer is too thick, the amount of light transmission is reduced, so that the solar cell characteristics are deteriorated.

When applied to a solar cell having a configuration in which light is incident through an organic flexible substrate, the light transmittance of the inorganic insulating layer at a wavelength of 550 nm is preferably 80% or more, particularly preferably 90% or more.

The inorganic insulating layer needs to have an insulating property so as not to cause a short circuit between the lower electrodes 4 divided into cell units of the solar cell. The sheet resistance of the inorganic insulating layer is 100
It is preferably at least kΩ / □, particularly preferably at least 1 MΩ / □.

The inorganic insulating layer is formed at least by plasma CVD.
The same pattern may be provided in the region where the film (photoelectric conversion layer 5) is formed. However, if the pattern includes this pattern, the pattern may be larger than this pattern, or may be formed over the entire surface of the organic flexible substrate. Good.

The inorganic insulating layer may be formed by a plasma CVD method, a sputtering method, an electron beam evaporation method, a plasma beam method, or the like. In the case where the inorganic insulating layer is formed using the above-described roll-to-roll method, Is preferably an electron beam evaporation method or a plasma beam method, particularly preferably a plasma beam method. In the plasma beam method, the deposition rate can be as high as, for example, about 5 to 12 nm / s. In addition, the organic flexible substrate is roll-to-
When a roll is used, the traveling speed of the substrate can be reduced, so that the inorganic insulating layer having a required thickness can be formed in one pass. Therefore, it is not necessary to reciprocate the organic flexible substrate many times. Further, the adhesion strength of the inorganic insulating layer to the substrate is higher than that of the electron beam evaporation method.

In the plasma beam method, evaporation is performed by heating an evaporation source with plasma. Since plasma is used for heating the evaporation source, a film can be formed at a higher speed than when heating is performed using an electron beam or an ion beam. When the plasma beam method is used for forming the inorganic insulating layer, preferable conditions are a film forming pressure of 1.3 × 10 ^{−3 to} 0.6 Pa, a plasma generation current of 100 to 200 A, and a substrate traveling speed of 0.2 to 1 m / min.
It is.

Although the film forming conditions when using the electron beam evaporation method are not particularly limited, the film forming pressure is set to 1 × 10 ⁻³ to
1.3 × 10 ⁻⁴ Pa and the traveling speed of the substrate is 30 to 50
m / min is preferable. In electron beam evaporation,
Usually, the organic flexible substrate is reciprocated a plurality of times to obtain an inorganic insulating layer having a desired thickness.

The inorganic insulating layer formed by each of the above methods is usually in an amorphous state.

The inorganic insulating layer containing a metal oxide as a main component is
It can also be formed by a so-called sol-gel method. In the sol-gel method, various metal alkoxides or oligomers thereof are condensed to obtain a metal oxide. The sol-gel method is particularly suitable for forming an inorganic insulating layer containing silicon oxide as a main component.

When the inorganic insulating layer containing silicon oxide as a main component is formed by a sol-gel method, the raw material compound is not particularly limited, but preferably a siloxane oligomer shown in the following (A) is used, and this is condensed. It is preferable to use a polysiloxane represented by the following (B).

[0033]

Embedded image

In each of the above (A) and (B), R represents an alkyl group or an aryl group. The carbon number of R is preferably 1 to 10, more preferably 1 to 6, and may be linear or branched. Specific examples of R include a methyl group, an ethyl group, (n,
i) -Propyl group, (n, i, sec, tert) -butyl group, phenyl group and the like, among which methyl group and phenyl group are preferable. In the above (B), black dots are Si atoms, and white circles are oxygen atoms.

The number average molecular weight (Mn) of the siloxane oligomer shown in (A) is preferably from 10 ³ to 10
⁶ In addition, the terminal of a siloxane oligomer is usually Si-OH.

When forming the inorganic insulating layer by the sol-gel method, first, a siloxane oligomer is dispersed in a solvent to form a coating solution. There is no particular limitation on the solvent used for preparing the coating solution. For example, when the siloxane oligomer shown in the above (A) is used, the solvent may be a water alcohol-based solvent.
An alcohol solvent, an aromatic solvent, an ester solvent, or the like, preferably an alcohol solvent may be used.

In the coating solution, a curing agent such as a chelate complex of aluminum, titanium or zirconium or a trialkyltin oxide may be added. When adding a curing agent, siloxane oligomer / curing agent (weight ratio)
Is preferably 90/10 to 99/1.

The solid content concentration in the coating solution is not particularly limited, but is preferably 10 to 30%, particularly preferably 20 to 30%. The viscosity of the coating solution is not particularly limited.
The viscosity at ℃ is usually 60 mPa · s or less, preferably 5 to 50 mPa · s.

The application means is not particularly limited, and a coating film may be formed on the substrate by a known method such as roll coating, spin coating, dipping, spraying and the like. In addition,
The rotation speed during spin coating is preferably 100 to 20.
00 rpm, more preferably 100 to 1000 rpm.

After the coating film is formed, it is subjected to a heat treatment and dried and cured. The heat treatment temperature may be selected at a temperature that the organic flexible substrate can withstand, but is usually selected from the range of 120 to 300 ° C.

The polysiloxane produced in this way has excellent durability.

The coating solution containing the siloxane oligomer shown in the above (A) is, for example, a ceramic coating material Glaska (HPC70 manufactured by JSR Corporation).
03, HPC7004, HPC7516), which can be preferably used in the present invention.

The inorganic insulating layer containing silicon oxide as a main component may contain an inorganic component other than silicon oxide in order to adjust the coefficient of thermal expansion. As such an inorganic component, for example, at least one of aluminum oxide, titanium oxide, zirconium oxide, zinc oxide and tin oxide is preferable. These contents in the inorganic insulating layer may be appropriately determined so as to obtain a desired coefficient of thermal expansion. In order to contain these inorganic components, a metal alkoxide containing a metal element to be added, such as Al or Ti, may be mixed with a siloxane oligomer and used.

Further, when it is necessary to increase the thermal expansion coefficient to adjust the thermal expansion coefficient, the inorganic insulating layer may contain a heat-resistant resin. As the heat-resistant resin in this case, polyetherketone or polyethersulfone is preferable. A commercially available heat-resistant resin can be used. For example, as polyether ketone, ICI company: “VICTREX PEEK”, “Victrex PEK”, Amoco company: “Kedell”, D
uPon: "PEEK", BASF: "Ultrapec", Hoechs: "Hostatec PEK", and the like. As polyether sulfone, Sumitomo Chemical Co., Ltd .: "VICTREXPES", Am
oco: "Kedell A", BASF: "Ultrason E" and the like can be used.

The content of the heat-resistant resin in the inorganic insulating layer is preferably 50% by weight or less, more preferably 5 to 30% by weight, based on the inorganic component such as silicon oxide.

In the present invention, the inorganic insulating layer may be composed of diamond-like carbon. Diamond-like carbon (DL
The C (Diamond Like Carbon) film is sometimes called a diamond-like carbon film, an i-carbon film, or the like. Regarding the diamond-like carbon film, see, for example,
646, JP-A-62-145647, NewD
iamond Forum, Vol. 4, No. 4 (October 25, 1988), Japanese Patent Application Laid-Open No. 11-158631, Japanese Patent Application Laid-Open
-44160, JP-A-10-190031, JP-A-10-275308, JP-A-10-2
89419 and the like. DLC, as described in the above document (New Diamond Forum),
In Raman spectroscopic analysis, a peak of a broad (1520~1560cm ^-1) Raman absorption at 1550 cm ^-1. That is, in Raman spectroscopy, 1333 cm ⁻¹
Diamond having a sharp peak at 1581 cm.sup.1, and graphite having a sharp peak at 1581 cm.sup.- ¹ are substances having structures distinctly different from each other. The DLC film is an amorphous thin film containing carbon and hydrogen as main components, and sp ³ bonds between carbon atoms are randomly present in the film. The atomic ratio C: H in DLC is usually about 95-60: 5-40. The DLC film, as shown in the above publications,
In addition to carbon and hydrogen, various elements such as Si, N,
At least one of O and F may be contained. DL
The C film can be formed by a plasma CVD method, an ionization vapor deposition method, a sputtering method, or the like.

[0047] In the lower electrode Figure 1, since the light from the surface of the organic flexible substrate 2 (upper side in the figure) is configured to incident normally constitute the lower electrode 4 from the metal. The metal constituting the lower electrode is not particularly limited. For example, Al or stainless steel may be used, but Al is preferably used. Since Al has a low specific resistance, deterioration due to energy loss and heat generation is small. By the way, in the solar cell, the light reflected by the lower electrode through the photoelectric conversion layer enters the photoelectric conversion layer again, and this reflected light is also converted into electric energy. Therefore, it is preferable that the lower electrode has a high reflectance, but Al having a high light reflectance is also excellent in this respect. Further, Al has high thermal conductivity, and
It has good corrosion resistance and is inexpensive. The thickness of the lower electrode made of metal is not particularly limited, but is preferably 0.01 to 10 μm.

On the other hand, when light is incident through the organic flexible substrate 2, the lower electrode 4 is made of a transparent conductive material. The transparent conductive material to be used is not particularly limited, but tin oxide, ITO (indium tin oxide), and ZnO are preferable because they have good transparency and conductivity. The thickness of the lower electrode made of a transparent conductive material is usually preferably 10 to 100 nm.

The lower electrode is preferably formed by a vapor phase growth method such as a sputtering method.

Diffusion-preventing layer Between the lower electrode 4 and the photoelectric conversion layer 5, stainless steel, stainless steel, and the like are used to prevent the lower electrode constituent components from diffusing into the photoelectric conversion layer and to lower the interface between them. It is preferable to provide a diffusion prevention layer made of a metal such as Ti or Cr. The thickness of the diffusion preventing layer is preferably 3 to 5 nm. The diffusion preventing layer may be usually formed by a vapor deposition method such as a sputtering method.

Photoelectric Conversion Layer In the illustrated solar cell, the photoelectric conversion layer 5 is the plasma CVD film of the present invention. First, the plasma CVD film of the present invention will be generally described. In the present invention, the plasma CVD film may be in contact with the inorganic insulating layer, or another layer may be interposed between the inorganic insulating layer and the plasma CVD film. In any case, swelling of the organic flexible substrate in the patterning film formation region is suppressed. In the present invention, the swelling of the patterning film formation region can be easily suppressed to 100 μm or less,
It can be suppressed to 50 μm or less.

In the plasma CVD method, an AC plasma is usually used, and the frequency can be from a few hertz to a microwave.

In forming a plasma CVD film, a source gas corresponding to the film composition is used.
00 ° C, operating pressure 1.3 ~ 266Pa, input power 30
What is necessary is just to about 600 mW / cm < ² > (frequency 13.56MHz).

The thickness of the plasma CVD film may be determined as needed. The plasma CVD film may be composed of only one layer or two or more layers. However, the bulge of the organic flexible substrate generated during the formation of the plasma CVD film is generally increased as the plasma CVD film is thicker. The present invention is particularly effective when at least one relatively thick plasma CVD film is included. The relatively thick plasma CVD film has a thickness of, for example, about 400 nm or more. Although there is no particular upper limit on the thickness of the plasma CVD film, it is usually about 4 μm. Even when the plasma CVD film is so thick, the effects of the present invention are sufficiently realized.

The plasma CVD film may be in an amorphous state or a microcrystalline state.

Next, the photoelectric conversion layer 5 will be specifically described. The photoelectric conversion layer 5 is preferably made of single-crystal silicon, microcrystalline silicon, or amorphous silicon having a pn junction or a pin junction, preferably a pin junction. A pn junction or a pin junction can be formed by adding a predetermined impurity when forming the photoelectric conversion layer.

Hereinafter, as a preferred combination example, an n-type semiconductor layer composed of microcrystalline silicon, a photovoltaic layer (i-layer) composed of amorphous silicon, and a p-type semiconductor layer composed of microcrystalline silicon are laminated. The photoelectric conversion layer described above will be described.

The p-type semiconductor layer contains B or the like as an impurity. The impurity content is preferably 1 to 2 atomic%. Preferably, the thickness is between 20 and 30 nm. p
The mold semiconductor layer uses SiH ₄ , H ₂ , B ₂ H ₆ or the like as a source gas, a substrate temperature of 110 to 130 ° C., and a film forming pressure of 133 to 130 ° C.
266 Pa, input power 100 to 300 mW / cm ² (frequency 1
The film may be formed at about 3.56 MHz).

The i-layer preferably has a thickness of 400 to 800 nm. The i-layer uses SiH ₄ , H _2, or the like as a source gas, a substrate temperature of 160 to 180 ° C., and a deposition pressure of 66.5 to 66.5.
133 Pa, input power 60 to 150 mW / cm ² (frequency 1
The film may be formed at about 3.56 MHz).

The n-type semiconductor layer contains P and the like as impurities. The impurity content is preferably 1 to 2 at%. Preferably, the thickness is between 20 and 40 nm. The n-type semiconductor layer uses SiH ₄ , H ₂ , PH ₃ or the like as a source gas, a substrate temperature of 160 to 200 ° C., and a film forming pressure of 66.5 to 65 °
200 Pa, input power 60 to 150 mW / cm ² (frequency 1
The film may be formed at about 3.56 MHz).

[0061] The upper electrode Figure 1, since the light from the surface of the organic flexible substrate 2 (upper side in the figure) is configured to incident the upper electrode 6,
What is necessary is just to comprise from the above-mentioned transparent conductive material. When light is incident through the organic flexible substrate 2, the upper electrode 6 may be made of an opaque conductive material such as a metal.

Interlayer insulation layer, separator insulation layer Interlayer insulation layer 9 and separator insulation layer 1 in the illustrated example
The material constituting 0 is not particularly limited as long as it has an insulating property and can form the structure shown in the figure, but it is usually preferable to use an insulating resin. As the insulating resin, for example, a urethane resin, a phenoxy resin, or the like is preferable. The interlayer insulating layer 9 and the separator insulating layer 10
May be composed of the same material or different materials.

The thickness of the interlayer insulating layer 9 is preferably 5 to 40 μm, and the thickness of the flat portion of the separator insulating layer 10 is preferably 5 to 10 μm.

The interlayer insulating layer and the separator insulating layer may be usually formed by a coating method such as screen printing.
Interlayer insulating layer 9 and separator insulating layer 1 in the illustrated example
0 is usually formed by the following procedure. First, after forming the photoelectric conversion layer 5, the interlayer insulating layer 9 is formed in a predetermined pattern by screen printing or the like. Next, the interlayer insulating layer 9
After the upper electrode 6 is formed thereon, a groove penetrating the upper electrode 6, the interlayer insulating layer 9, the photoelectric conversion layer 5, and the lower electrode 4 is formed by, for example, laser processing. The stacked body from the lower electrode 4 to the upper electrode 6 is divided by the groove and separated into cells. Next, the separator insulating layer 1 is formed on the upper electrode 6.
0 is formed in a predetermined pattern by screen printing or the like. At this time, the insulating material penetrates into the groove, and the separator part 101 is formed.

The interlayer insulating layer 9 is provided in order to prevent a short circuit between the upper electrode 6 and the lower electrode 4 when the separator portion 101 is formed. In addition, the interlayer insulating layer 9 also has a function of improving the breakdown voltage of the solar cell. For example, if a minute defect or inhomogeneity exists in the photoelectric conversion layer 5, the lower electrode 4 is located at that position.
Although a short circuit may occur between the capacitor and the upper electrode 6, the provision of the interlayer insulating layer 9 forms a capacitor having a relatively high capacitance, so that such a dielectric breakdown can be prevented.

The constituent materials of the collecting / wiring electrode and the connecting conductor collecting / wiring electrode 11 are not particularly limited.
Usually, it is preferable to use Ag. The thickness of the collecting / wiring electrode is preferably 5 to 10 μm.

The collecting / wiring electrodes may be usually formed by a coating method such as screen printing. In the illustrated example, the collecting / wiring electrode 11 is usually formed in the following procedure. First, after forming the separator insulating layer 10, the collecting / wiring electrode 11 is formed in a predetermined pattern by screen printing or the like. Next, in a region where the interlayer insulating layer 9 does not exist, the collecting / wiring electrode 11 is perforated by, for example, laser processing, and the lower electrode 4 penetrates the upper electrode 6 and the photoelectric conversion layer 5.
To form holes. At the time of this perforation, the constituent material of the collecting / wiring electrode 11 is melted and penetrates into the hole, and the connection conductor 12 is formed.

Sealing Member A resin film is preferably used as a sealing member for suppressing mechanical damage, oxidation, corrosion and the like. The resin film may be formed by coating or sticking. The sealing member is preferably provided at least on the surface on the upper electrode 6 side, and more preferably on the back surface side of the organic flexible substrate 2.

Hereinafter, an example of a method for forming a resin film by sticking will be described. In this example, a sealing member in which a buffer adhesive layer containing a thermosetting resin is provided on at least one surface of a resin base material having a light transmitting property and a heat resistance property is used.

The resin base material has a glass transition point Tg of 65 ° C.
Or the heat-resistant temperature (or continuous use temperature) is 80
C. or higher, or a resin film that satisfies both of these conditions and has translucency. Such a resin film does not deteriorate in performance even when it is directly exposed to a light source such as sunlight and heated.

As a resin-made base material having a glass transition point Tg of 65 ° C. or higher and / or a heat-resistant temperature of 80 ° C. or higher, a polyethylene terephthalate film (Tg6
9 ° C), polyethylene naphthalate heat-resistant film (Tg
113 ° C.); ethylene trifluorochloride resin [PCTFE:
NEOFLON CTFE (manufactured by Daikin Industries, Ltd.)] (heat-resistant temperature 150 ° C.), polyvinylidene fluoride [PVDF:
Denka DX film (manufactured by Denki Kagaku Kogyo Co., Ltd.)] (heat-resistant temperature 150 ° C .: Tg 50 ° C.), polyvinyl fluoride [P
VF: Tedlar PVF film (manufactured by DuPont)] (heat-resistant temperature: 100 ° C.) or a fluoride homopolymer or ethylene tetrafluoride-perfluorovinyl ether copolymer [P
FA: Neoflon: PFA film (manufactured by Daikin Industries, Ltd.)] (heat resistant temperature: 260 ° C.), ethylene tetrafluoride-hexafluoropropylene copolymer [FEP: Toyofuron film FEP type (manufactured by Toray Industries, Inc.)] ° C), tetrafluoroethylene-ethylene copolymer [ETFE: Tefzel ETFE film (manufactured by DuPont) (heat resistant temperature 150
° C), AFLEX film (manufactured by Asahi Glass Co., Ltd .: Tg83)
℃)] or other fluorine-based film; aromatic dicarboxylic acid-bisphenol copolymerized aromatic polyester [PAR: casting (ELMEC manufactured by Kaneka Chemical Co., Ltd.)] (heat-resistant temperature: 290 ° C .: Tg 215 ° C.) Acrylate film; polysulfone [PSF:
Sumilite FS-1200 (Sumitomo Bakelite)
(Tg 190 ° C.), polyether sulfone [PES: Sumilite FS-1300 (Sumitomo Bakelite)] (Tg
Polycarbonate film [PC: Panlite (manufactured by Teijin Chemicals Ltd.)]
(Tg 150 ° C); functional norbornene resin [ARTON (manufactured by JSR)] (heat-resistant temperature 164 ° C:
Tg 171 ° C.); polymethyl methacrylate (PMM
A) (Tg 93 ° C); olefin-maleimide copolymer [TI-160 (manufactured by Tosoh Corporation)] (Tg 150 ° C or more), para-aramid [Aramica R: manufactured by Asahi Kasei Corporation] (heat-resistant temperature 200 ° C), fluorinated polyimide (heat-resistant) Temperature 200 ° C
Above), polystyrene (Tg 90 ° C), polyvinyl chloride (Tg 70-80 ° C), cellulose triacetate (Tg
g 107 ° C).

Among these, the polyethylene naphthalate heat-resistant film (Tg 113 ° C.) has a higher heat resistance (Tg), heat resistance during long-term use, Young's modulus (stiffness), breaking strength, and heat shrinkage rate than the polyethylene terephthalate film. , Low oligomers, excellent gas barrier properties, hydrolysis resistance, water vapor transmission rate, thermal expansion coefficient, physical property deterioration due to light, etc., and breaking strength compared to other polymers , Heat resistance, dimensional stability, moisture permeability,
Because it is excellent in terms of total balance such as cost,
preferable.

The glass transition point Tg of the resin substrate is preferably at least 65 ° C., more preferably at least 70 ° C., further preferably at least 80 ° C., particularly preferably at least 110 ° C. Although the upper limit of Tg is not particularly limited, it is usually 130 ° C.
It is about. Further, the heat resistant temperature or the continuous use temperature is preferably 80 ° C. or more, more preferably 100 ° C. or more, and further preferably 110 ° C. or more. The higher the heat resistance temperature or the continuous use temperature, the better, and the upper limit is not particularly limited, but is usually about 250 ° C.

The thickness of the resin substrate may be appropriately determined according to the structure of the solar cell, the strength and the bending rigidity required for the resin substrate, etc., and is usually 5 to 100 μm.

The transmissivity of the resin substrate is preferably such that 70% or more, particularly 80% or more of the light in the visible light region is transmitted.

The buffer adhesive layer preferably contains a thermosetting resin component and an organic peroxide before thermocompression bonding.

As the thermosetting resin component, ethylene-vinyl acetate copolymer [EVA (vinyl acetate content of 15 to
About 50%)].

Examples of the organic peroxide include 2,5-dimethylhexane-2,5-dihydroperoxide;
2,5-dimethyl-2,5-di (t-butylperoxy) hexane-3; di-t-butyl peroxide;
2,5-dimethyl-2,5-di (t-butylperoxy) hexane; dicumyl peroxide; α, α′-bis (t-butylperoxyisopropyl) benzene; n
-Butyl-4,4-bis (t-butylperoxy) valerate; 2,2-bis (t-butylperoxy) butane; 1,1-bis (t-butylperoxy) -3,3
5-trimethylcyclohexane; t-butylperoxybenzate; benzoyl peroxide can be used. These may be used alone or in combination of two or more, and the combination ratio when using in combination is arbitrary. The amount of the organic peroxide to be used per 100 parts by weight of the thermosetting resin component is preferably 10 parts by weight or less, more preferably 0.5 to 6 parts by weight.

The thickness of the buffer adhesive layer may be appropriately determined according to the structure of the solar cell, the use environment, and the like, but is preferably 3 to 500 μm, more preferably 3 to 50 μm, and still more preferably 10 to 40 μm. . If the buffer adhesive layer is too thin, the buffer effect will be insufficient. On the other hand, when the buffer adhesive layer is too thick, the light transmittance is reduced, and burrs are easily generated at the time of punching or the like. However, since the buffer adhesive layer has much better light transmittance than the resin base material, when used under high illuminance such as outdoors, there may be no problem even if the thickness is increased to about 10 mm.

As means for providing the buffer adhesive layer on the resin substrate, known means such as coating or extrusion coating can be used.

The buffer adhesive layer may be embossed. When laminating the sealing member to the solar cell,
If embossing is performed so that a passage for bubbles is formed, mixing of bubbles is reduced.

Next, an example of a method for forming a resin film by coating will be described. The resin film formed by the coating method is slightly inferior in terms of flatness, weather resistance, etc., compared to the resin film formed by sticking, but it is used when incorporated into equipment or used mainly for indoor use. Is no problem. In the coating method, the laminating step and the subsequent flattening step required in the above-mentioned attaching method can be omitted, so that the manufacturing cost can be reduced.

The resin used in this case has excellent transparency,
It is preferable that there is little discoloration due to aging and light deterioration, and particularly preferable is a thermosetting resin. As the thermosetting resin, for example, a fluorine resin, polyurethane, polyester, epoxy resin, and phenoxy resin can be used. The resin coating may be formed by a screen printing method, a spin coating method, or the like.

[0084]

EXAMPLE 1-1 An organic flexible substrate is 360 mm long and 460 m wide.
m, polyethylene naphthalate (PEN) with a thickness of 75 μm
A film (manufactured by Teijin, trade name Neotex) was used. This organic flexible substrate has a melting point of 273 ° C., a glass transition point of 113 ° C., and a light transmittance of 85% at a wavelength of 550 nm.
Met.

First, a 0.8 μm-thick silicon oxide (SiO ₂ ) film was formed on the entire surface of the organic flexible substrate by electron beam evaporation to form an inorganic insulating layer. The deposition pressure was 4 × 10 ⁻³ Pa. The sheet resistance of this inorganic insulating layer was 10 ² MΩ / □. The light transmittance of this inorganic insulating layer at a wavelength of 550 nm was 95%.

Next, 120 amorphous silicon (a-Si) films having a diameter of 14 mm and a thickness of 0.7 μm were formed on the inorganic insulating layer by a plasma CVD method using a mask. The raw material gas and its flow rate are SiH ₄ : 50 sccm,
H ₂ : 500 sccm, the substrate temperature was 160 ° C., the operating pressure was 133 Pa, and the input power was 100 W (13.56 MHz).

As a result, no drum-shaped swell was observed in the a-Si film forming region. And this a-Si
When a patterning film was formed on the film by film formation of a mask, the alignment of the mask was easy, and the patterning film could be laminated.

Even when the inorganic insulating layer was made of silicon nitride, silicon carbide, aluminum oxide or DLC, no swelling was observed in the patterning film (a-Si film) formation region. Similar effects were obtained when the substrate was made of polyethersulfone, polyimide, polyamide, or polyimideamide and each of the inorganic insulating layers was formed.

Example 1-2 An inorganic insulating layer was formed on the PEN organic flexible substrate used in Example 1-1 by a plasma beam method. The conditions in the plasma beam method were as follows: background pressure: 2.7 × 10 ⁻³ Pa, film formation pressure: 8.0 × 10 ⁻² Pa, Ar gas flow rate: 20 sccm, and plasma generation current: 170 A. The sheet resistance of this inorganic insulating layer is 120 MΩ /
It was □. The light transmittance of this inorganic insulating layer at a wavelength of 550 nm was 82%.

Next, an a-Si film was formed on the inorganic insulating layer in the same manner as in Example 1-1. As a result, a-Si
No drum-like swell was observed in the film-forming region.
Then, when a patterning film was formed on the a-Si film by forming a mask, the alignment of the mask could be easily performed and the patterning film could be laminated.

Example 1-3 A siloxane oligomer solution was applied on the organic flexible substrate made of PEN used in Example 1-1 by a roll coating method. Next, it was cured by holding at 220 ° C. for 20 minutes to form a 2 μm-thick inorganic insulating layer made of polysiloxane. This siloxane oligomer solution is
R Co., Ltd. ceramic coating material Glaska (H
PC7003), which contains a siloxane oligomer in which R is a methyl group in the above (A), contains an alcohol-based solvent, has a solid concentration of 20%, and a viscosity of 10 mPa · s. The sheet resistance of this inorganic insulating layer was 60 MΩ / □. The light transmittance of this inorganic insulating layer at a wavelength of 550 nm was 83%.

Next, an a-Si film was formed on the inorganic insulating layer in the same manner as in Example 1-1. As a result, a-Si
No drum-like swell was observed in the film-forming region.
Then, when a patterning film was formed on the a-Si film by forming a mask, the alignment of the mask could be easily performed and the patterning film could be laminated.

Comparative Example 1 An a-Si film was formed on the organic flexible substrate made of PEN used in Example 1-1 in the same manner as in Example 1-1. That is, no inorganic insulating layer was provided. As a result, in the a-Si film formation region, a swelling of several hundred micrometers in height was recognized in the organic flexible substrate.
Then, when an attempt was made to form a patterning film on the a-Si film by forming a mask, it was impossible to position the mask.

Example 2 A solar cell having the structure shown in FIG. 1 was manufactured in the following procedure.

An inorganic insulating layer (0.7 μm thick) made of silicon oxide (SiO ₂ ) was formed on the organic flexible substrate 2 made of PEN used in Example 1-1 by electron beam evaporation.
m) 3 was formed. The deposition pressure was 3 × 10 ⁻³ Pa. The sheet resistance of the inorganic insulating layer 3 was 80 MΩ / □.
The light transmittance of this inorganic insulating layer 3 at a wavelength of 550 nm was 93%.

Next, 120 lower electrodes 4 made of Al and having a diameter of 14.2 mm and a thickness of 0.3 μm were formed by sputtering, and further formed thereon of stainless steel having a thickness of 5 nm.
Was formed.

Next, a photoelectric conversion layer 5 was formed on the diffusion preventing layer by the following procedure. First, an n-type microcrystalline silicon layer was formed into a mask to a thickness of 20 nm by a plasma CVD method.
At this time, the raw material gas and its flow rate were: PH ₃ + H ₂ mixed gas (PH ₃ / H ₂ = 0.2%): 30 sc
cm, SiH ₄ : 5 sccm, H ₂ : 750 sccm, and other conditions were as follows: substrate temperature: 160 ° C., operating pressure: 133 Pa, input power: 100 W (13.56 MHz). Subsequently, the i-type amorphous silicon layer is
A mask was formed to a thickness of 0 nm by a plasma CVD method. At that time, the source gas and the flow rate were SiH ₄ : 50 sccm, H ₂ : 500 sccm, and other conditions were the substrate temperature: 160 ° C., the operating pressure: 133 Pa, and the input power: 100 W (13.56 MHz). Subsequently, a p-type microcrystalline silicon layer was formed as a mask to a thickness of 20 nm by a plasma CVD method. At that time, the raw material gas and its flow rate were B ₂ H ₆ + H ₂ mixed gas (B ₂ H ₆ / H ₂ = 0.2%): 20
sccm, SiH ₄ : 5 sccm, H ₂ : 950 sccm, and other conditions were as follows: substrate temperature: 110 ° C., operating pressure: 133 Pa, input power: 200 W (13.56 MHz).

Next, a urethane-based insulating resin composition was printed in a predetermined pattern on the photoelectric conversion layer 5 by a screen printing method using a 150-mesh polyester screen, and then left in an oven at 160 ° C. for 10 minutes. And heat-cured to form an interlayer insulating layer 9 having a thickness of 20 μm.

Next, a transparent electrode 6 having a thickness of 60 nm was formed by sputtering in an Ar atmosphere using ITO (indium tin oxide) as a target.

Next, a groove was formed by laser scribing, and a urethane insulating resin composition was screen-printed thereon to form a 10 μm-thick separator insulating layer 10 having a separator portion 101.

Next, the silver paste was screen-printed and cured to form a 6 μm thick collecting / wiring electrode 11.
Was formed. Finally, a silver paste was screen-printed to form a plus-side extraction electrode and a minus-side extraction electrode, thereby completing a solar cell.

The solar cell was irradiated with light using a solar simulator and the photocurrent was measured. As a result, it was confirmed that the solar cell functioned as a solar cell.

Comparative Example 2 An attempt was made to manufacture a solar cell in the same manner as in Example 2 except that the inorganic insulating layer 3 was not provided. However, the organic flexible substrate had a height of several hundred micrometers in the i-type amorphous silicon layer formation region. The excitement was recognized.
Then, when an attempt was made to form a p-type microcrystalline silicon layer on the i-type amorphous silicon layer by forming a mask, it was impossible to align the mask.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration example of a solar cell as an example of a functional component of the present invention.

[Explanation of symbols]

 Reference Signs List 2 organic flexible substrate 3 inorganic insulating layer 4 lower electrode 5 photoelectric conversion layer 6 upper electrode 9 interlayer insulating layer 10 separator insulating layer 101 separator section 11 collection / wiring electrode 12 connection conductor

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshito Yamamoto 1-13-1 Nihonbashi, Chuo-ku, Tokyo Inside TDK Corporation (72) Inventor Shinichi Tezuka 1-13-1 Nihonbashi, Chuo-ku, Tokyo Inside TDK Corporation (72) Inventor Toru Kineri Inside 13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation

Claims (10)

[Claims] 1. A functional component having an inorganic insulating layer on an organic flexible substrate and a plasma CVD film on the inorganic insulating layer. 2. The functional component according to claim 1, wherein the plasma CVD film is formed by patterning using a mask. 3. The thickness of the inorganic insulating layer is 50 nm to 10 μm.
The functional component according to claim 1, wherein m is m. 4. A sheet resistance of the inorganic insulating layer is 100 k.
The functional component according to any one of claims 1 to 3, which has an Ω / □ or more. 5. The method according to claim 1, wherein the inorganic insulating layer comprises at least one of Si and Al and at least one of oxygen, nitrogen and carbon.
The functional component according to any one of claims 1 to 4, wherein the functional component contains a seed or contains diamond-like carbon. 6. The functional component according to claim 1, wherein said plasma CVD film contains silicon. 7. The functional component according to claim 1, wherein said organic flexible substrate is made of polyethylene naphthalate, polyether sulfone, polyimide, polyamide or polyimide amide. 8. A method for manufacturing a functional component, comprising the steps of: forming an inorganic insulating layer on the entire surface of an organic flexible substrate; and patterning the inorganic insulating layer by using a mask to laminate a plasma CVD film. 9. The method according to claim 8, wherein a plasma beam method is used for forming the inorganic insulating layer. 10. The method for manufacturing a functional component according to claim 8, wherein the functional component according to claim 1 is obtained.