Solar cell device and preparation method based on strained heterojunction quantum dots

Abstract

The present invention relates to the field of solar cell material. Provided are a solar cell device based on strain type heterojunction quantum dots and manufacturing method thereof. The solar cell device comprises at least two Ge / Si quantum dot structural layers grown on a doped silica-based substrate (1); the Ge / Si quantum dot structural layers comprise Si film layers (3) having Ge quantum dots (2) of 2-7 nm in diameter, the innermost Si film layer (3) being 2-4 nm, and increasing incrementally therefrom; the outermost quantum dot structural layer is SiO2 cover film layer (4) filling gaps between quantum dots, forming a multi-layer structure of quantum dot array filling film; a silicon doped layer protective film (5) of 10-20 nm in thickness is grown on the cover film layer (4); electrodes (7) are grown on the outer surfaces of the silicon doped layer (5) and the silica-based substrate (1). The energy band ranges from 0.4 eV to 0.22 eV and the corresponding conversion efficiency is 55%-57%, an increase of more than 7% compared to the prior art, significantly improving the photoelectric conversion efficiency of a solar cell.

Description

technical field [0001] The invention relates to a solar cell, in particular to a solar cell device based on strained heterojunction quantum dots, and to a preparation method thereof, belonging to the field of solar cell materials. Background technique [0002] Solar energy is an inexhaustible renewable and clean energy source on the earth. The efficient use of solar energy is one of the core topics that research institutions and industries are focusing on at present, including solar cells based on photoelectric conversion effects. devices and applications. Quantum dot solar cell technology is a new generation technology of current solar cell research. [0003] Solar cells based on semiconductor quantum dots have the following characteristics: the size of quantum dots is in the scale of several nanometers, often called "artificial atoms", the energy band structure is affected by the three-dimensional quantum size effect, the energy level is discontinuous, and the scale of qu...

AI Technical Summary

Problems solved by technology

However, the strain effect and its effective utilization in solar cells have not been reported in the above-mentioned patent documents and currently known related documents.

Images