Nano silicon window layer with gradient band gap characteristic and preparation method thereof

Abstract

The invention relates to a nano silicon window layer with the gradient band gap characteristic, which is formed by depositing on the surface of a sample to be processed, wherein the surface of the sample to be processed is sequentially stacked with a metal back electrode M, a transparent conductive back electrode T1, an n-type Si-based thin film N and an intrinsic Si-based thin film I. The nano silicon window layer is formed by sequentially stacking a silicon thin film P1, a silicon thin film P2 and a silicon thin film P3. A preparation method of the nano silicon window layer comprises the following steps: depositing the p-type silicon thin film P1 with small thickness under a low glow power; then gradually raising the power and depositing the thin film P2; and finally, and completing the window layer P3 under a high power. The nano silicon window layer has the advantages that when the nano silicon window layer is applied to the window layer of an n-i-p-type silicon-based thin film solar cell, high electric conductance and wide band gap can be acquired, the bombardment of a solar cell i / p interface can be effectively reduced, the band gap matching between an intrinsic layer and the window layer can be implemented and the filling factor, the open-circuit voltage and the spectral response of the solar cell are obviously improved, so that the silicon-based thin film solar cell with high photoelectric conversion efficiency is obtained.

Description

technical field [0001] The invention relates to a silicon-based solar cell preparation process, in particular to a nano-silicon window layer with gradient band gap characteristics and a preparation method thereof. Background technique [0002] Solar cells are one of the effective ways to solve the increasingly severe environmental problems and energy supply problems. Due to the wide application of silicon materials in the semiconductor industry, and people have a very clear understanding of the various characteristics of silicon materials. Therefore, silicon-based solar cells occupy a very important position in all solar cells, among which solar cells related to amorphous silicon include amorphous silicon-based thin-film solar cells (including microcrystalline silicon and amorphous silicon germanium, etc.), and amorphous silicon-based solar cells HIT type heterojunction solar cells composed of crystalline silicon / monocrystalline silicon. [0003] Among silicon-based thin-f...

AI Technical Summary

Problems solved by technology

If the glow power is low, it is difficult to obtain a wide band gap; if the glow power is high, it is easy to cause bombardment damage to the interface, causing damage to the i / p interface in n-i-p amorphous silicon solar cells, reducing the solar cell performance

[0007] From the above analysis, it can be seen that p-type nano-silicon (nc-Si:H) as the window layer of amorphous silicon solar cells must solve two problems: 1) damage caused by high-energy particle bombardment during high-glow power deposition; 2) ) bandgap matching and bandgap transition between the wide bandgap window layer and the lower bandgap intrinsic layer

Images