On Optimization Design And Manufacturing Technology For GaInP/Ga(In)As/Ge Triple-junction Solar Cells

The third generation of solar cells, GaInP/Ga(In)As/Ge triple-junction solar cells have been focused in reason of high efficiency, desirable temperature characteristics, strong anti-radiation etc. in concentrator photovoltaics and aerospace areas. However, the domestic triple-junction solar cells industry of upstream epitaxial chip is still weak now. The solar cells performance need to be further enhanced in order to reduce the cost of concentrator photovoltaics and enhance the reliability and lifetime of the space solar-cells.The purpose of this paper is to produce highly efficient triple-junction solar cells. By increasing cells efficiency and improve cells performance tunnel-junction, improved cells at higher times the condenser performance conditions, we obtained a 750-fold concentration production efficiency of 40.7% for the concentrator photovoltaics solar cells. The anti-radiation structure of space triple-junction solar cells is designed, which is based on analysis of the irradiated damage characteristics by experiments, efficiency of remaining increased 2.3%. The efficiency of triple-junction solar space cells with 31% are fabricated through optimizing epitaxial structure and chip structure.First, the key technologies and key parameters involved in the epitaxial growth and chip production are given. To optimize the epitaxial growth, the epitaxial growth equipment MOCVD and characterization of epitaxial material properties testing equipment have been analyzed and summarized. In order to research and optimize cells performance which provides data feedback at debug, chip key production processes and cell performance tests is analyzed. With the control experiments, the GalnP material properties of distortion are studied, and it gives a different effect on the growth parameters characteristic of disordered GalnP material and the physical mechanism. Although the doping technology and the pn junction interface processing solve the difficulties to the epitaxial growth of light transmissive n++ GaInP/p++ AlGaAs tunnel junction, we completed optimization from 500-fold to 750-fold concentrator cells by temperature and surfactants integrated parameter adjustment and optimization antireflection film. For the cells technology development and the environment used in aerospace, attenuation characteristics of the cells and loss mechanism are researched, the design of anti-radiation structure is finished by the TFCalc optical design software. Then by epitaxial growth and comparison, we verify that the excellent performance of anti-radiation structure, combining with optimized chip AR film, extension of the high light transmission tunnel junction and the disordered GaInP top cell and integrated debugging, gives the final completion of the large-size space-efficient triple junction solar cells.