Improved light absorption in GaAs solar cell with optical structures and etching process

Abstract

In this thesis, we fabricated a flexible GaAs solar module with an active area of 43.56 cm2 using the laser-assisted-bonding(LAB) which reduces warpage and enable pitch bonding. Each cell was fabricated by the internal stress-assisted ELO process. An additional micro prism array (MPA) has been employed to improve Pout. By employing MPA structures, the Pout was enhanced by 5.6 %. Also, we fabricated GaAs solar module with an active area of 102.85 cm2. By encapsulating MPA with subwavelength structure, the Jsc was enhanced by 5%. We fabricated two types of GaAs solar cell. First type was fabricated using hybrid wet and dry etching process with glass substrate. We measured dark current of this device. Second type is GaAs solar cell with ITO all deposited on the front side to reduce series resistance. 11.3 % of efficiency was measured. For device fabrication, low surface damage dry etching method and ohmic contact formation between ITO and Al0.5In0.5P was developed.