Wet chemical cleaning of plasma oxide grown on heated (001) InP surfaces

Published

August 1, 2004

Author(s)

Bogdan Lita, O Pluchery, R L. Opila, Y J. Chabal, G. Bunea, J P. Holman, E J. Bekos

Abstract

Wet chemical cleaning is performed prior to most semiconductor processing steps, including epitaxial growth, metal and dielectric film deposition, and diffusion, with the purpose of removing unwanted chemical species that reside on the wafer surface. In this article, we report the results of our investigations of a specific type of residue that is formed due to the interaction between CF_4/Od2 plasmas and heated (001) InP surfaces. Our studies indicate that these residues are homogeneous oxides, about 10 nm thick, and that they impede wafer processing. In addition, these "plasma oxides" do not show significant growth after removing the wafer from the plasma and storing it in ambient. Moreover, we identify several aqueous solutions, such as HF and HNO_{3 that can be used for the removing the plasma residues at room temperature. For example, HNO}d3 and dilute HF solutions are shown to be effective in removing the plasma oxide and likely induce re-growth of oxides similar to those found on "epi-ready"-like surfaces. In general, chemical cleaning in aqueous acidic solutions tends to stabilize the surface, with little further growth of oxide in the hours following the wet chemical cleaning.

Citation

Journal of Vacuum Science and Technology B

Volume

22

Issue

4

Pub Type

Journals

Keywords

acidic solution, etching, III-V semiconductors, indium compounds, oxidation, plasma processing, surface cleaning

Citation

Lita, B. , Pluchery, O. , Opila, R. , Chabal, Y. , Bunea, G. , Holman, J. and Bekos, E. (2004), Wet chemical cleaning of plasma oxide grown on heated (001) InP surfaces, Journal of Vacuum Science and Technology B (Accessed April 26, 2024)