Cleaning of GaN surfaces

L. L. Smith, S. W. King, Robert Nemanich, R. F. Davis

Research output: Contribution to journalArticle

103 Citations (Scopus)

Abstract

The work described in this paper is part of a systematic study of surface cleaning and ohmic contact strategies for GaN. The goal of this investigation was to determine the most effective methods of wet chemical and thermal desorption cleaning for the removal of oxygen (O) and carbon (C) prior to metallization. Hydrochloric (HCl) and hydrofluoric (HF) acid-based cleaning treatments were compared, and thermal desorption as a function of temperature was characterized by sequential heating under ultra high vacuum (UHV) conditions. Auger electron spectroscopy (AES) analysis was used to monitor the presence of surface O and C throughout the study. For the removal of surface oxide, HCl-based solutions were found to be most effective; under as-cleaned, air-exposed conditions, HCl:DI H2O (1:1) solution resulted in the lowest levels of residual O and C. However, HF-based solutions resulted in more effective thermal desorption of C from the surfaces. In contrast to the results typically observed in the thermal desorption cleaning of GaAs, complete removal of oxygen and carbon from airexposed GaN surfaces was not seen using vacuum heating alone, even to temperatures where GaN decomposition occurs (>800-900°C). The results of this study indicate that the presence of oxygen and carbon on the GaN surface is persistent even to high temperatures, and that further in-situ cleaning methods must be added to obtain spectroscopically clean GaN surfaces.

Original languageEnglish (US)
Pages (from-to)805-810
Number of pages6
JournalJournal of Electronic Materials
Volume25
Issue number5
StatePublished - May 1996
Externally publishedYes

Fingerprint

cleaning
Cleaning
Thermal desorption
desorption
Carbon
Oxygen
carbon
Hydrofluoric Acid
oxygen
Surface cleaning
Heating
Hydrofluoric acid
Hydrochloric Acid
Ohmic contacts
Ultrahigh vacuum
Auger electron spectroscopy
Hydrochloric acid
heating
Metallizing
hydrochloric acid

Keywords

  • Auger electron spectroscopy (AES)
  • Gallium nitride
  • Metallization
  • Ohmic contacts
  • Surface analysis
  • Surface cleaning
  • Thermal desorption

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Materials Science(all)
  • Electronic, Optical and Magnetic Materials
  • Physics and Astronomy (miscellaneous)

Cite this

Smith, L. L., King, S. W., Nemanich, R., & Davis, R. F. (1996). Cleaning of GaN surfaces. Journal of Electronic Materials, 25(5), 805-810.

Cleaning of GaN surfaces. / Smith, L. L.; King, S. W.; Nemanich, Robert; Davis, R. F.

In: Journal of Electronic Materials, Vol. 25, No. 5, 05.1996, p. 805-810.

Research output: Contribution to journalArticle

Smith, LL, King, SW, Nemanich, R & Davis, RF 1996, 'Cleaning of GaN surfaces', Journal of Electronic Materials, vol. 25, no. 5, pp. 805-810.
Smith LL, King SW, Nemanich R, Davis RF. Cleaning of GaN surfaces. Journal of Electronic Materials. 1996 May;25(5):805-810.
Smith, L. L. ; King, S. W. ; Nemanich, Robert ; Davis, R. F. / Cleaning of GaN surfaces. In: Journal of Electronic Materials. 1996 ; Vol. 25, No. 5. pp. 805-810.
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