Accession Number : ADA192752

Title :   An In-Situ Ellipsometric Study of Aqueous NH4OH Treatment of Silicon.

Descriptive Note : Interim technical rept.,

Corporate Author : NORTH CAROLINA UNIV AT CHAPEL HILL DEPT OF CHEMISTRY

Personal Author(s) : Gould, G ; Irene, E A

PDF Url : ADA192752

Report Date : 25 Mar 1988

Pagination or Media Count : 30

Abstract : In-situ ellipsometry is used to analyze silicon surfaces in an aqueous ammonium hydroxide ambient. The ellipsometric data indicate that a surface which is optically quite similar to bare silicon is obtained when the native silicon dioxide film is etched from a Si substrate by aqueous NH4OH. In contrast, the surface obtained by etching the native oxide in aqueous buffered hydrogen fluoride leads to formation of a residual film on the Si substrate. Roughening of sample surfaces treated with either aqueous NH4OH or BHF is observed by microscopy. The high degree of roughness obtained following NH4OH treatment appears to influence ellipsometric measurements on samples, but this influence is not observed following BHF exposure where less roughness is noted.

Descriptors :   *AMMONIUM COMPOUNDS, *HYDROXIDES, *SILICON, ELLIPSOMETERS, ETCHING, FILMS, LIQUIDS, MICROSCOPY, OXIDES, RESIDUALS, ROUGHNESS, SILICON DIOXIDE, SUBSTRATES, SURFACES

Subject Categories : Inorganic Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE