JPS5952883A - Solar battery - Google Patents

Abstract

PURPOSE:To obtain the solar battery with which energy gap can be adjusted by a method wherein each layer of amorphous semiconductor which forms the junction of the solar battery is formed by a specific element, thereby enabling to form the junction using the semiconductor of same type. CONSTITUTION:A P layer 2, an i-layer and an N layer 4 are formed on a metal substrate 1, a transparent conductive film 5 and a lattice electrode 6 are formed thereon, and the solar battery is formed. The P layer 2, i-layer 3 and N layer 4 are all amorphous semiconductor thin films consisting of the three elements of B, Si and P, and hydrogen is added to the above so that it can be used as the terminator to be used to terminate a dangling bond. The quantity of B contained in the P-layer is larger than that of P and the quantity of P contained in the N layer 4 is larger than that of B, and the control of charged particles is performed using said layers 2 and 4. On the other hand, as the quantity of B and P contained in the i-layer 3 is same or the quantity of either of B and P may be increased than that of the other for performance of compensation. This kind of semiconductor thin film can be formed simply and continuously using the same facilities by merely changing for each layer the compounding ratio of SiH4, B2H6 and PH3 as raw gas using a glow discharge decomposition method, and an excellent junction can also be obtained, thereby enabling to manufacture the solar battery of high conversion efficiency.

Description

[Detailed description of the invention] Unexploded IJ1. This invention relates to a solar cell using an amorphous semiconductor.

Since it was discovered that amorphous silicon can control charged electrons, the application of amorphous semiconductors to solar cells has attracted particular attention, and research has been conducted in various fields. Among these, from the viewpoint of effective utilization of sunlight λ, efforts have been made to use core element amorphous semiconductors made by adding other group II elements to silicon.

For example, by mixing carbon with silicon in the layer on the light incident side, the optical band gap is widened.

As a result, the amount of light reaching the current generation region made only of silicon increases.On the contrary, in the layer forming the current generation region, the forbidden band width can be reduced by mixing gel manila l with silicon. to effectively absorb solar energy. However, in these methods, the semiconductors constituting each layer are of different types, forming a heterojunction, making it technically difficult to create the junction.

In the present invention, a junction is formed from the same type of semiconductor without forming such a heterojunction, and moreover, the energy and
It is an object of the present invention to provide a solar cell in which the gap is adjustable.

The purpose of this is to ensure that each layer of the amorphous semiconductor that forms the junction of the solar cell consists of at least one identical element arranged in each of the If1, ■, and V nuclei, and an element that terminates the dangling bond. achieved by.

The present invention is based on the idea that each layer of a solar cell is formed by a composite semiconductor consisting of the same IVFZ element semiconductor and (1)-(2) compound semiconductor.

Hereinafter, an embodiment of the present invention will be described with reference to FIG. In the solar cell shown in FIG. 1, a p-layer 2 is formed on a metal substrate 1.
．． One layer 3.9 layers 4 are formed of semiconductor thin films, and a transparent conductive film 5 and a grid electrode 6 are further provided thereon. pl@2.1 layer 3. n7#4 is an amorphous semiconductor layer made of three elements, B, Si, and P, and hydrogen is added as a terminator for terminating dangling bonds. FIG. 2 shows the distribution of the content of each element in each layer of the amorphous semiconductor. P layer 2 has more B than P, 9 layers 4
contains more P or B, which controls charge electrons. On the other hand, in the j layer, the amounts of B and P may be the same, or either Bit or PJt may be larger for compensation.

The semiconductor layer IN of such a solar cell is prepared by, for example, glow discharge decomposition method using SIH' +B2H6 as a raw material gas.
,PH! By simply changing the formulation of each layer in accordance with each layer, the same general cloth can be formed continuously and extremely easily, and a good 18-layer product can be obtained. Moreover, the greatest feature of the present invention is that the energy and gap of the semiconductor can be adjusted by adjusting the ratio of the amount (s+p) to the amount of Sl. Therefore 1M3 energy gear,
Align the whelk with the maximum point of the solar energy spectrum,
It is also easy to manufacture solar cells with high conversion efficiency.

As described above, the present invention provides a thin film semiconductor solar cell which is made of the same type of semiconductor and whose characteristics can be easily adjusted. G instead of Sl as the original cable
It goes without saying that AI, In, +la can be used in addition to B as group elements, and St) + As can be used in addition to P as travel elements, and not only hydrogen but also halogen or chalcogen elements can be used as 0 terminators. Good too. “In addition to the aforementioned n-1-p structure, it can also be applied to solar cells with a Schottky barrier type structure.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a solar cell according to an embodiment of the present invention, and FIG. 2 is a view of Si in the thickness direction of the semiconductor layer. It is a distribution diagram of the content of B and P elements.

Claims (1)

[Claims] 1) Each 1- of the amorphous semiconductor forming the junction is
1. A solar cell comprising at least one element belonging to each of the VD and one flags and an element terminating a dangling bond.