Wet chemical cleaning process of GaAs substrate for ready-to-use

• Published in: Journal of crystal growth Vol. 264; no. 1; pp. 98 - 103
• Main Authors: Song, J.S., Choi, Y.C., Seo, S.H., Oh, D.C., Cho, M.W., Yao, T., Oh, M.H.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.03.2004; Elsevier
• Subjects: A1. Surface processes; B1. Semiconducting gallium arsenide; Clean metal, semiconductor, and insulator surfaces; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Electron and ion emission by liquids and solids; impact phenomena; Exact sciences and technology; Interface structure and roughness; Photoemission and photoelectron spectra; Physics; Solid surfaces and solid-solid interfaces; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); B1. Semiconducting gallium arsenide; A1. Surface processes; 81.65.cf; 81.05.Ea; Atomic force microscopy; Gallium arsenides; Inorganic compounds; Photoluminescence; Roughness; Binary compounds; Experimental study; Ellipsometry; Thickness; 81.65.cf A1. Surface processes; Wet cleaning; III-V semiconductors; X-ray photoelectron spectra
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2003.12.063

We investigate the wet chemical cleaning process of GaAs substrate for ready-to-use. To prepare epi-ready GaAs wafer, we used NH 4OH mixture to remove particles and metals as a first step of wet-chemical cleaning and acidic peroxide mixture to remove residual metallic contaminants and control the components of oxide layer as a second step of wet-chemical cleaning. The particle-free, metal-free, and thin As-oxide rich surface is achieved by the proposed ratio of NH 4OH mixture followed by HCl mixture among the second step of wet-chemical cleaning solution used in this experiment. Metal-contamination was analyzed by total reflection X-ray fluorescence spectroscopy. Characterization of the oxide composition was carried out by X-ray photoelectron spectroscopy. Surface morphology and thickness of oxide layer were observed by atomic force microscopy and ellipsometer, which show very flat surface roughness of 0.95 nm, and uniform oxide thickness of about 2 nm, respectively.