Bulk Stain Effect in Silicon Substrates HF Interaction with Boron Diffused Silicon.
Abstract
The interaction between silicon and concentrated HF has been studied using bulk silicon, discrete devices, and integrated circuits. Processed silicon wafers, when exposed to concentrated HF under illumination, form a stain of varying depth (approx. 0.1 to 3 micrometers) into the p+ regions. It has been shown that the effect is the result of an electrochemical reaction under conditions that provide an adequate flow of holes to the silicon-electrolyte interface. The free energy or the potential for the reaction is provided by two types of photovoltaic junctions, one within the semiconductor and the other at the silicon-HF interface. The reaction product is essentially silicon having an oxygen content that varies with the extent of completion of the anodization reaction. The HF-silicon reaction does not seem to depend on any bulk or process-induced defects, and no correlation with reliability or yield has been found. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1975
- Accession Number
- ADA013110
Entities
People
- J. W. Ostroski
- P. D. Blais
- P. Rai-choudhury
Organizations
- Westinghouse Electric Corporation