Sensitization of Porous Silicon with Germanium Quantum Dots for Up-Conversion of Low Energy Photons via Intermediate Band for Third Generation Solar Cells

摘要

Incorporation of germanium quantum dots (QDs) in porous silicon (PS) promises foundation of efficient intermediate band (IB) within the bandgap of the host material. We have developed the idealized model for such material system intended to be used for third generation solar cells. We solved Schrodinger equation for a chain of Ge nanodots embedded in a pore of columnar porous silicon material. We have shown that holes induce narrow energy band lined up with the forbidden band gap of Si and spreads over some distance from the chain into Si. The last feature is very desirable for efficient operation of IB structure associated with PS solar cells.