Research on Stable, High-Efficiency, Amorphous Silicon Multijunction Modules: Final Subcontract Report, 1 May 1990 - 30 June 1993

This report describes work performed during the period 1 July 1992 through 30 June 1993. During this period, major improvements were achieved in the stabilized conversion efficiency of triple-junction modules. These resulted in the demonstration of triple-junction initial conversion efficiency of 11.3% and stabilized conversion efficiency of approximately 9%. Significant advances were made in thedeposition of a-Si:H intrinsic layers that led to higher open-circuit voltage and improved stability. Thin microcrystalline n-layers were developed and scaled up for the recombination junctions in triple-junction modules that resulted in higher open-circuit voltage and fill factors. These improvements resulted in the demonstration of a-Si/a-Si/a-SiGe triple-junction modules with initialconversion efficiencies as high as 11.35% and 'stabilized' efficiencies of about 9%.