Characterization and Defect Analysis of Multijunction Solar Cell by Luminescence Technology
Tzu-Huan Cheng1, Chi-Chung Wu1, Chan-Peng Chang2, Hung-Pin Chen3, Chun-Ping Chen1, Wen-Jeng Ho4, Yu-Ren Chen4
1LiveStrong Optoelectronics Co., Ltd., Kaohsiung, Taiwan
/2National Applied Research Laboratories, National Space Organization, Hsinchu, Taiwan
/3Department of Optics and Photonics, National Central University ITRC, National Applied Research Lab, Hsinchu, Taiwan
/4National Taipei University of Technology, Taipei, Taiwan

Luminescence technology (electroluminescence and photoluminescence) of the space solar cell with monolithic GaInP/GaInAs/Ge triple-junction is investigated to probe each subcell quality. The luminescence from the GaInP, GaInAs, and Ge junctions are observed at the wavelengths of 0.7, 0.9, and 1.8 μm, respectively. The emission from band-to-band transition, phonon-replica emission, recombination via tunneling junction and defects are also characterized. By adjusting the excitation wavelength, photoluminescence can probe individual subcell. Electroluminescence can measure the spectral uniformity and defects of individual subcell with selected filter. The PL and EL emission are related to absorption edge and the temperature coefficient can be used to design the current match condition at operation temperature and power generation calculation as real environment.

Area: Sub-Area 5.5: Advanced Characterization of Photovoltaic Devices