THIS PROJECT WILL FOCUS ON DE-RISKING SINGLE-CRYSTAL CDTE SOLAR CELLS GROWN ON INEXPENSIVE SILICON TEMPLATES WITHOUT POST-GROWTH HALIDE TREATMENTS AS A PROTOTYPE TO MORE STABLE, HIGH EFFICIENCY CDTE SOLAR CELLS. HIGH DEPOSITION RATE BY CLOSE-SPACE SUBLIMATION (CSS) OF SINGLE-CRYSTAL CDTE ON A SILICON SUBSTRATE IS THE FIRST KEY OBJECTIVE TOWARD LOW COST TANDEM SOLAR CELLS. IN PARALLEL, MOLECULAR BEAM EPITAXY (MBE) GROWTH OF SINGLE-CRYSTAL CDTE ON SILICON SUBSTRATES WILL PROVIDE A BASELINE FOR THE FINAL SOLAR CELL ARCHITECTURE AND ACHIEVABLE DOPING. THE TEAM WILL EXPLORE DOPING THE CSS-GROWN CDTE BY POST-DEPOSITION DIFFUSION DOPING AND IN SITU CSS DOPING WITH A MULTI-SOURCE DEPOSITION SYSTEM. THE PROJECT DURATION IS A 12-MONTH, SINGLE BUDGET PERIOD.