The Small Business Innovation Research (SBIR) Phase I project seeks to develop significantly high-efficiency photovoltaic-cells (a.k.a. solar-cells) for clean electrical energy generation commercial applications. Conventional solar cell has the limitation in conversion efficiency, basically structured dependent. For example, it is ~18% for Si-crystal and 10% for amorphous-Si (a-Si) based Solar cell. It is required to develop solar cell utilizing material systems, which are matured, friendly to manufacturing, and can be fabricated using low-cost substrate (e.g. glass). A goal of the Phase I program is to carry on research and development of a-Si-solar cell for conversion efficiency of >25%, utilizing the glass-substrate. The design, performance simulation, and parameters optimization will be carried out during the Phase I activity period. <br/><br/>The proposed high-efficiency a-Si solar cell structure is widely applicable to next generation commercial applications. According to the recent report from the US Department of Energy (DOE), today's global market for solar cells for all commercial applications is $7-billion and it is estimated to grow with >40% per year, reaching $39-billion in 2014. Commercial applications include residential applications (on-grid/off-grid), industrial applications (both on-grid and off-grid), and consumer products (e.g. cell phones, PDAs).