Thin-Film Amorphous Silicon Alloy Research Partnership, Phase I: Annual Technical Progress Report, 2 February 1995 - 1 February 1996

This report describes the research performed during Phase I of a three-phase, 3-year program that is intended to expand, enhance, and accelerate knowledge and capabilities for developing high-performance, two-terminal, multijunction amorphous silicon (a-Si) alloy modules. A multijunction, multibandgap approach has the potential of achieving the highest stable efficiency in a-Si alloy solar cells.In this approach, the bandgap of the materials of the component cells is varied to capture a wide spectrum of the solar photons. Significant progress has been made in the development of materials and cell design in the last few years; however, to meet the Department of Energy goal of 12% stable module efficiency by 1998, it is necessary to make further improvements in each of the component cells. New back reflectors also need to be developed to facilitate improved light-trapping performance. The aim of this program is to develop a manufacturing technology; the research work must address issues involving scale-up, reliability, and cost, and issues that encompass module interconnect and encapsulation methods, as well.