JPH1126786A - Integrated optical power generating element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent drop of optical electromotive force occurring at another element even if one element is hidden with sun shadow, by comprising a difference optical power generating element and a plurality of optical power generating elements of such shape as subordinate to it, and electrically connecting together the optical power generating elements while a desired electro motive force is generated. SOLUTION: An optical power generating element 1 of annular shape is defined as a reference element. A plurality of optical power generating elements 2 subordinate to the optical power generating element 1 are provided. Here, the optical power generating elements 2 are in such an annular state as with concentric position relation ship. Here, the requires numbers of optical power generating elements 2 for generating a desired electro motive force are provided. Adjoining elements are electrically connected together at connection parts 3. Further, on the optical power generating element 2 wherein a + terminal 4 is set on the farthest side or the optical power generating element 1, a - terminal is provided. Even if such 3 shadow as only-element is hidden takes place, drop of optical electromotive force is prevented by preventing phenomenon wherein an optical electromotive force generated at an irradiated element is also decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an integrated photovoltaic element having a semiconductor layer as a photovoltaic layer.

[0002]

2. Description of the Related Art FIG. 2 is a plan view of an integrated photovoltaic element already in practical use, and FIG. 3 is a cross-sectional view taken along a solid line AB in the plan view 2.

In FIG. 3, a semiconductor layer 13 is a power generation layer made of amorphous silicon. The amorphous silicon layer further has a three-layer structure composed of a P-type semiconductor, an intrinsic semiconductor, and an N-type semiconductor.

Here, when light is incident from the glass substrate 11 side, the incident light passes through the lower electrode 12 which is a transparent conductive film and reaches the semiconductor layer 13. In the intrinsic semiconductor layer in the semiconductor layer 13, holes and electron pairs are generated by photoexcitation,
After this is amplified by the P and N semiconductors in contact with both sides of the intrinsic semiconductor layer, holes are introduced into the lower electrode 12 and electrons are introduced into the upper electrodes 14a and 14b.
Is positively charged, and the upper electrodes 14a and 14b are negatively charged.

Further, the lower electrode 12 of the element 7 and the upper electrode 14 of the element 6 are in electrical contact at the connection 8. Therefore, the element 7 and the element 6 are connected in series with each other. Similarly, in the plan view 2, all the adjacent elements are connected in series, so that a desired photoelectromotive force can be extracted. become.

By the way, the amorphous silicon forming the semiconductor layer 13 has a low resistivity during light irradiation and becomes a low-resistivity body through which a relatively large amount of current flows. As a result, the current hardly flows as a high resistivity body.

For this reason, the photocurrent generated in the intrinsic semiconductor layer moves relatively easily through the semiconductor layer during light irradiation, whereas the resistivity rapidly increases during non-irradiation, making it extremely difficult to move the current. Become.

Further, in the plan view 2, all photovoltaic elements are connected in series with each other. Therefore, even when only one photovoltaic element is in the non-irradiated state, for example, the shade portion 17 having a shape as shown in FIG.
6 is completely covered, the photovoltaic element 16
Is a very high-resistivity resistor, which also causes a reduction in the photovoltaic power generated by the other three photovoltaic elements connected in series.

As a result, a phenomenon occurs in which the photovoltaic power generated in the entire integrated photovoltaic element is greatly reduced even though only a part of the integrated photovoltaic element is not irradiated. Will be.

[0010]

SUMMARY OF THE INVENTION The present invention reduces the photovoltaic power generated by other photovoltaic elements, even though only one element is hidden by the partially generated shade. Trying to solve the problem.

[0011]

In order to achieve the above object, an integrated photovoltaic device of the present invention employs the following structure. The integrated photovoltaic device of the present invention includes a photovoltaic device 1 as a reference and a plurality of photovoltaic devices 2 having a shape dependent on the photovoltaic device 1 as a reference. And a desired electromotive force is generated.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A photovoltaic element 1 as a reference and a plurality of photovoltaic elements 2 having a shape dependent on the photovoltaic element 1 as a reference are electrically connected to each other. And an integrated photovoltaic element, which generates a desired electromotive force.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the shape of an integrated photovoltaic element according to an embodiment of the present invention will be described in detail with reference to plan views 1, 5, 6 and a sectional view taken along a solid line CD in FIG. Will be described. First, the planar structure will be described. In the plan view 1,
The ring-shaped photovoltaic element 1 is determined as a reference element. Next, a plurality of photovoltaic elements 2 dependent on the photovoltaic element 1 are installed. At this time, the photovoltaic element 2 has a ring shape having a concentric positional relationship with the photovoltaic element 1.

At this time, the photovoltaic elements 2 are provided in a number sufficient to generate a desired electromotive force. Adjacent elements are electrically connected to each other at the connection portion 3. Further, a positive terminal 4 is provided on the photovoltaic element 1 serving as a reference, and a negative terminal 5 is provided on the photovoltaic element 2 provided at the outermost side.

Next, the sectional structure of the photovoltaic elements 1 and 2 and the connecting portion 3 will be described with reference to FIG. First, in the cross-sectional view of FIG.
Is formed. At this time, the lower electrode 21 is formed of two regions, a region of the photovoltaic device 1 and a region extending from the connection portion 3 to the photovoltaic device 2. A gap of the order is provided. The material of the lower electrode 21 made of a transparent conductive film is an indium tin oxide film (ITO), and the film thickness is 1
It is 200 μm.

Further, in the photovoltaic elements 1 and 2, a semiconductor layer 22 is formed above the lower electrode 21. The semiconductor layer 22 is made of amorphous silicon (a-Si), and further includes a P-type semiconductor (P layer) and an intrinsic semiconductor (I-Si).
Layer) and an N-type semiconductor (N layer). The thickness of each layer was 300 ° and 6000, respectively.
４００, 400 μm.

Next, an upper electrode 23 is formed on the semiconductor layer 22.
Is formed. The upper electrode 23 has a two-layer structure made of different metal species. The metal layer 23a which is in direct contact with the semiconductor layer 22 is made of 300 μm thick Ti, and the upper electrode 23b is made of 2000 μm thick Al. Is used.

At this time, the upper electrode 23 laminated on the photovoltaic element 1 has a shape extending to the lower electrode 21 of the photovoltaic element 2 which protrudes long toward the photovoltaic element 1, and accordingly, 1 and 2 are electrically contacted at the connection portion 3.

Similarly, all adjacent photovoltaic elements in the plan view 1 are connected at the connection portion 3.

According to the above arrangement, the photovoltaic power generated by the other illuminated element is obtained despite the shade that only one element is hidden, as seen in the conventional type. Can be prevented.
The mechanism will be described below in comparison with the conventional type.

As described above, in the conventional integrated type photovoltaic device, when the shade as shown in FIG. 4 is generated, the photovoltaic power is significantly reduced. However, when the integrated photovoltaic element according to the present invention is used, even when the shade portion 26 having the shape as shown in FIG. 8 covers the cell, both the element 24 and the element 25 are completely covered by the shade. It won't. Therefore, in each element, a part of the element always receives light irradiation.

If the amorphous silicon layer in the light-irradiated state receives even part of the light, the resistivity of that part decreases, and the generated photocurrent easily flows through the low-resistance part. Will be able to Therefore,
It is not possible to prevent the phenomenon that a completely shaded element becomes a resistor and lowers the photovoltaic power generated by other elements, as was the case with conventional integrated photovoltaic elements. become able to.

[0023]

According to the conventional integrated type photovoltaic element, even though only a part of the photovoltaic element has become non-irradiated due to the partial shading, the photovoltaic element is irradiated. The phenomenon that the photovoltaic power that has been generated is also reduced has been observed. However, according to the present invention, it has become possible to secure a stable photovoltaic power without lowering the photovoltaic power.

[Brief description of the drawings]

FIG. 1 is a plan view showing a photovoltaic device according to an embodiment of the present invention.

FIG. 2 is a plan view showing a conventional photovoltaic element.

FIG. 3 is a sectional view showing a conventional photovoltaic element.

FIG. 4 is a plan view showing a conventional photovoltaic element.

FIG. 5 is a plan view of a photovoltaic device according to an embodiment of the present invention.

FIG. 6 is a plan view of a photovoltaic device according to an embodiment of the present invention.

FIG. 7 is a sectional view of a photovoltaic device according to an embodiment of the present invention.

FIG. 8 is a plan view of a photovoltaic device according to an embodiment of the present invention.

[Explanation of symbols]

 1, 2 photovoltaic element 3, 8 connecting part 4, 9 + terminal 5, 10 − terminal 11, 20 glass substrate 12, 21 lower electrode 13, 22 semiconductor film 14a, 14b upper electrode 15 irradiated photovoltaic element 16 Non-irradiated photovoltaic element 17, 26 Shade 18 Date display window 19 Second hand

Claims (4)

[Claims] 1. A reference photovoltaic device and a plurality of photovoltaic devices having a shape dependent on the reference photovoltaic device, wherein the photovoltaic devices are electrically connected to each other, and An integrated photovoltaic element, which generates a desired electromotive force. 2. The integrated photovoltaic device according to claim 1, wherein
Reference photovoltaic element 1 and reference photovoltaic element 1
Wherein the plurality of photovoltaic elements 2 each having a shape dependent on (1) are ring-shaped. 3. The integrated photovoltaic device according to claim 1, wherein
An integrated photovoltaic device, wherein the photovoltaic device has a shape in which an opening is provided in a part thereof. 4. The integrated photovoltaic device according to claim 1, wherein
An integrated photovoltaic element, wherein the photovoltaic element has a shape in which the photovoltaic element is partially omitted.