高压GaAs微型太阳电池阵列的制备

Fabrication of High Voltage GaAs Micro-Solar Cell Arrays

为了提高GaAs微型太阳电池的输出性能,对微型太阳电池阵列的主要工艺进行了研究和改进。通过对帽层、背电极层和台面的选择性/非选择性湿法腐蚀工艺的探索,实现了对最佳腐蚀液的配比、腐蚀时间和温度的控制。采用侧壁钝化工艺和聚酰亚氨(PI)/SiO2/TiAu/SiO2新型互连结构,不仅确保了电池单元之间有效的隔离和互连,而且极大地降低了侧壁载流子复合电流,同时这种新型互连结构可有效防止由于衬底光敏现象引起的漏电流。经过上述器件工艺改进,获得了高集成度GaAs微型太阳电池阵列。电流-电压(JSC-VOC)测试结果显示,器件的开路电压达到84.2V,填充因子为57%。

The main fabrication processes were investigated and improved in order to improve the output performance of GaAs micro-solar cells.The selective/unselective etching was carried out for the cap layer,back cathode layer and mesa of the cell,and the control of the optimum et-ching solution ratio,etching time and temperature was obtained by exploring the wet etching process.The sidewall passivation process and the novel interconnected structure of polymide（PI）/SiO2/TiAu/SiO2 were proposed to ensure the effective insulation and interconnection be-tween the cell units,greatly reduce the carriers recombination current of the sidewall and prevent the substrate leakage current due to the photosensitivity of the SI-GaAs substrate.By improving the fabrication technology mentioned above,the GaAs micro-solar cell array with high integration level was fabricated.The result of the current-voltage measurement shows that the open-circuit voltage of 84 V and the fill factor of 57% were achieved.