摘要 |
<p>An optimized narrow band gap alloy which is especially useful in tandem photovoltaic devices is formed from germanium, tin and or lead and at least one density of states reducing element. The depositing species are activated in a UHV, contaminant-free environment and deposited to form a contaminant-free, substantially tetrahedrally co-ordinated alloy material with hydrid orbitals. Fluorine is preferably added to the alloy material to (1) reduce the density of state through compensation, and (2) promote and expand elements with which it bonds into tetrahedral co-ordinatior whereby heretofore unavailable orbitals may be utilized.</p> |