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Title: Properties of GaP(001) surfaces treated in aqueous HF solutions

Abstract

Chemically cleaned GaP(001) surfaces in aqueous HF solutions have been studied using spectroscopic ellipsometry (SE), ex situ atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS), wettability, and photoluminescence (PL) measurements. The SE data clearly indicate that the solutions cause removal of the native oxide film immediately upon immersing the sample ({<=}1 min). The SE data, however, suggest that the native oxide film cannot be completely etch-removed. This is due to the fact that as soon as the etched sample is exposed to air, the oxide starts to regrow. The SE estimated roughness is {approx}1 nm, while the AFM roughness value is {approx}0.3 nm. The XPS spectra confirm the removal of the native oxide and also the presence of regrown oxide on the HF-etched GaP surface. The wettability measurements indicate that the HF-cleaned surface is hydrophobic, which is in direct contrast to those obtained from alkaline-cleaned surfaces (hydrophilic). A slight increase in the PL intensity is also observed after etching in aqueous HF solutions.

Authors:
;  [1]
  1. Department of Electronic Engineering, Faculty of Engineering, Gunma University, Kiryu-shi, Gunma 376-8515 (Japan)
Publication Date:
OSTI Identifier:
20979413
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 11; Other Information: DOI: 10.1063/1.2737781; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AIR; ATOMIC FORCE MICROSCOPY; ELLIPSOMETRY; ETCHING; FILMS; GALLIUM PHOSPHIDES; OXIDES; PHOTOLUMINESCENCE; ROUGHNESS; SEMICONDUCTOR MATERIALS; SOLUTIONS; SURFACE TREATMENTS; SURFACES; WETTABILITY; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Morota, Hiroaki, and Adachi, Sadao. Properties of GaP(001) surfaces treated in aqueous HF solutions. United States: N. p., 2007. Web. doi:10.1063/1.2737781.
Morota, Hiroaki, & Adachi, Sadao. Properties of GaP(001) surfaces treated in aqueous HF solutions. United States. doi:10.1063/1.2737781.
Morota, Hiroaki, and Adachi, Sadao. Fri . "Properties of GaP(001) surfaces treated in aqueous HF solutions". United States. doi:10.1063/1.2737781.
@article{osti_20979413,
title = {Properties of GaP(001) surfaces treated in aqueous HF solutions},
author = {Morota, Hiroaki and Adachi, Sadao},
abstractNote = {Chemically cleaned GaP(001) surfaces in aqueous HF solutions have been studied using spectroscopic ellipsometry (SE), ex situ atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS), wettability, and photoluminescence (PL) measurements. The SE data clearly indicate that the solutions cause removal of the native oxide film immediately upon immersing the sample ({<=}1 min). The SE data, however, suggest that the native oxide film cannot be completely etch-removed. This is due to the fact that as soon as the etched sample is exposed to air, the oxide starts to regrow. The SE estimated roughness is {approx}1 nm, while the AFM roughness value is {approx}0.3 nm. The XPS spectra confirm the removal of the native oxide and also the presence of regrown oxide on the HF-etched GaP surface. The wettability measurements indicate that the HF-cleaned surface is hydrophobic, which is in direct contrast to those obtained from alkaline-cleaned surfaces (hydrophilic). A slight increase in the PL intensity is also observed after etching in aqueous HF solutions.},
doi = {10.1063/1.2737781},
journal = {Journal of Applied Physics},
number = 11,
volume = 101,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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