Electrode design and planar uniformity of anodically etched small area porous silicon

Abstract

Porous silicon layer microstructure is sensitive to many parameters, which need to be controlled during etching. These include not only anodization time, current density, applied potential and electrolyte composition but also the structure of electrodes. In the electrochemical formation cell of porous silicon the structure of electrodes greatly influences the planar uniformity of the porous silicon layer. In this paper a systematic study of the planar uniformity of small area porous silicon layer formed by different electrode structure is reported based on photoluminescence. A new design of the electrode structure is developed for achieving satisfactory planar uniformity of small area porous silicon layer.