InAs量子点尺寸和间距对GaInP/GaAs/GaInAs/Ge多结叠层电池的影响

A metamorphic GaInP/GaAs/GaInAs/Ge multi-junction solar cell with InAs quantum dots is investigated, and the analytical expression of the energy conversion efficiency on the multi-junction tandem solar cell is derived using the detailed balance principle and the Kronig-Penney model.The influences of interdot distance, quantum-dot size and the intermediate band location on the energy conversion efficiency are studied.This shows that the maximum efficiency,as a function of quantum-dot size and distance,is about 60.15%under the maximum concentration for only one InAs/GaAs subcell,and is even up to 39.69%for the overall cell.In addition,other efficiency factors such as current mismatch,the formation of a quasicontinuum conduction band and concentrated light are examined.     

基于均匀度和平稳度的激光光束匀化性评价

针对激光光束匀化的目的和特性,对现有的光束匀化性评价方法进行了分析,说明了这些方法的特点和存在的问题。提出了一种基于均匀度和平稳度的光束匀化性评价方法,该方法使用面阵CCD采集激光光强分布图像,通过图像处理分析光斑图像,采用均匀度和平稳度评价方法对光斑的整体能量分布和散斑进行评价。实验结果表明该评价方法可以较好地反映激光光束匀化状况。     

基于InGaAs渐变缓冲层的太阳能电池的研究

This paper uses an InGaAs graded buffer layer to solve the problem of lattice mismatch and device performance degradation. In the graded buffer layer, we choose the ＂transition layer＂ and the ＂cover layer＂ to accommodate the 3.9% mismatch. No threading dislocations were observed in the uppermost part of the epitaxial layer stack when using a transmission electron microscope （TEM）. We analyze the factors which influence the saturation current. Simulation data shows that the cells grown by metal organic vapor phase epitaxy （MOVPE） have considerable open circuit voltage, short circuit current, and photoelectric conversion efficiency. Finally we propose that InP may have great development potential as a substrate material.