The effect of etching with glycerol, and the interferometric measurements on the interface roughness of porous silicon

✍ Scribed by Kan, P. Y. Y. ;Foss, S. E. ;Finstad, T. G.

• Book ID: 105363150
• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 253 KB
• Volume: 202
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200461173

✦ Synopsis

Abstract

We have carried out interferometric measurements of interface roughness in‐situ during electrochemical etching of p‐type porous silicon (PS) at room temperature. We found that at a certain porosity (∼70%) and with an electrolyte where a low fraction (10%) of the ethanol was replaced with glycerol, there was a significant decrease of the interface roughness. However, a higher content of glycerol (>10%) increased the surface roughness. We have varied the current density in the electrolytic cell and the HF concentration of the electrolyte. We also found that the porosity of the PS varied only slightly when glycerol at various concentrations was used. This investigation shows that an interferometric technique could be a useful tool for measuring the etch rate and the interface roughness of the PS. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)