SOLAR CELL DEVICE BASED ON STRAIN TYPE HETEROJUNCTION QUANTUM DOTS AND MANUFACTURING METHOD THEREOF

摘要

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.