Oxidized Porous Silicon Based SOI: untapped resources

This paper discusses new potentialities of oxidized porous silicon (PS) based SOI structures that have hitherto escaped attention of the researchers. Oxidized PS (OPS) has the property of controlling its characteristics depending on regimes of formation of PS layer and its further oxidation. The manner by which electrical and optical properties of the OPS layer may be varied with oxidation regimes of PS layers with various porosities is presented. It is of great importance that oxidized PS regions of different characteristics (porosity, thickness etc.) may be formed simultaneously within the same wafer. The paper points out the meaning of oxidized PS. It is emphasized, by one way or another, that oxidized PS involves a whole series of dissimilar materials. PS may be oxidized either completely or partially and the formed OPS layer will have its properties depending on both the oxidizing regimes and the parameters of initial PS. The kinetics of PS oxidation and densification, the electrical and optical parameters of the material obtained and the feasibility to dope OPS with a desirable dopant are presented. Dopants in OPS are considered on the example of rare-earth elements. In addition, consideration is given to the ideas of on-chip integration PS-based SOI with different PS-based micro- and optoelectronic devices.