MI-AlxGa 1-xAs/GaAs太阳电池中界面势的构成及其界面复合分析

在MIp-AlxGa1-xAs结构的I层表面上，引入固定负电荷，并用减反射膜覆盖。将p-Al1-xGaxAs层中的空穴感应至界面，可建立界面电子感应势垒，并将其构成MIp-AlxGa1-xAs/p-n-n^ -GaAs太阳电池。通过求解泊松方程，理论上分析了界面感应势的高度、宽度与p-AlxGa1-xAs层掺杂浓度及减反射膜中固定负电荷面密度的关系，以及该感应势的建立对电池界面复合速度的影响。结果表明，p-AlxGa1-xAs层掺杂浓度的降低以及固定负电荷面密度的增高，都将导致界面感应势的高度与宽度的增加，从而能有效降低电池界面复合速度几个量级，相应地可大大提高电池的开路电压。

COMPOSING OF INTERFACE POTENTIAL IN MI-AlxGal-xAs/GaAs SOLAR CELL AND ANALYSIS OF INTERFACE RECOMBINATION

By introducing fixed negative charges on the surface of insulation layer of MIp Al x Ga 1 x As which were covered by anti reflection coating, the holes in p Al x Ga 1 x As layer were induced to interface, and the induced potential of electrons on interface was established. Then the MIp Al x Ga 1 x As/ p n n + GaAs solar cell was formed. In this paper, by means of finding the solution of the Poisson equation, the effect of the doping concentration of p Al x Ga 1 x As and the area density of fixed negative charges in anti reflection coating on the height and width of interface induced potential, and the influence on interface recombination speed of solar cell were theoretically investigated. The result shows that, the decrease of doping concentration of p Al x Ga 1 x As and the increase of area density of fixed negative charges would lead to the increasing of the height and width of interface induced potential. And it would be good for reducing the interface recombination velocity. Then the open circuit voltage should rise greatly.