9 - Porous Silicon

Abstract

This chapter focuses on the light-emitting aspect of PSi that has been explored since 1990. Visible luminescence in PSi is basically due to quantum confinement, however, oxygen complexes also contribute significantly. The morphology maybe improved by reducing the etching rate. Silicon can be epitaxially grown on PSi. The chapter argues that the possibility of embedding luminescent QDs of CdSe or PbS into high-porosity PSi, sealed off by epitaxial silicon growth, offers the best chance for electronic and optoelectronic applications. The possibility of introducing luminescent QDs, even with a periodic pattern, into PSi followed by epitaxial Si growth maybe useful in optoelectronic applications. And replacing luminescent QDs by wide-gap QDs may serve as a gate capacitor to control source–drain current in a field effect transistor. Therefore, the capability of epitaxial growth on PSi has enormous device potential.