Quantum structures for next-generation solar cells

Abstract

Recently, quantum dots have attracted significant attention as a possible means of exploiting below-bandgap photons to generate additional photocurrents beyond those corresponding to band-to-band transitions in the bulk, and hence obtain higher efficiencies in solar cells. In order to achieve this goal, a fabrication technique in order to obtain a sufficiently high density as well as good size homogeneity of quantum dots is a prerequisite. It has been known for some time that multilayer stacking of self-organized quantum dots is a promising way of increasing the total dot density. Our aim is to realize multilayer InAs quantum dot superlattice structures by a strain compensation growth technique, and integrate the dot structure into solar cells.