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Title: Distribution of free carriers near heavily-doped epitaxial surfaces of n-type Ge(100) upon HF and HCl treatments

Carrier distributions near n-type epitaxially-grown Ge(100) surfaces with high impurity concentrations (1 × 10{sup 20} cm{sup −3}) were studied using high resolution electron energy loss spectroscopy (HREELS) upon surface treatments in aqueous solutions of HF and HCl. After surface treatments with HCl and HF, the molecular vibration modes distinctly showed either chloride or hydride terminations of Ge surfaces with negligible oxidation. The free-carrier concentration profile was inferred from the conduction band plasmon measurements as a function of the incident electron energies employing a dielectric theory simulation with a 4-layer structure and an effective electron mass of 0.02m{sub 0}. A carrier-free layer of 40 and 24 Å were derived for HCl- and HF-treated Ge(100), respectively. The surface band bending was estimated to be 0.32 eV for HF-treated Ge. HCl-treated Ge surfaces showed a band bending of 0.91 eV attributed to the strong effect of the surface Cl-Ge dipole.
Authors:
; ; ;  [1]
  1. Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8562 (Japan)
Publication Date:
OSTI Identifier:
22492155
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 5; Journal Issue: 10; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AQUEOUS SOLUTIONS; CONCENTRATION RATIO; DIELECTRIC MATERIALS; DOPED MATERIALS; ELECTRONS; ENERGY-LOSS SPECTROSCOPY; EPITAXY; EV RANGE; GERMANIUM; HYDRIDES; HYDROCHLORIC ACID; HYDROFLUORIC ACID; LAYERS; N-TYPE CONDUCTORS; OSCILLATION MODES; OXIDATION; SURFACE TREATMENTS; SURFACES