Electronically Controlled Chemical Stability of Compound Semiconductor Surfaces

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalNot applicablepeer-review

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Author(s)

  • Junning Gao
  • Yeonbae Lee
  • Kin Man Yu
  • Samuel S. Mao
  • Wladek Walukiewicz

Related Research Unit(s)

Detail(s)

Original languageEnglish
Pages (from-to)32543-32551
Journal / PublicationACS applied materials & interfaces
Volume11
Issue number35
Online published13 Aug 2019
Publication statusPublished - 4 Sep 2019

Abstract

Effects of a humid environment on the degradation of semiconductors were studied to understand the role of the surface charge on material stability. Two distinctly different semiconductors with the Fermi level stabilization energy EFS located inside the conduction band (CdO) and valence band (SnTe) were selected, and effects of an exposure to 85 °C and 85% relative humidity conditions on their electrical properties were investigated. Undoped CdO films with bulk Fermi level EF below EFS and positively charged surface are very unstable. The stability greatly improves with doping when EF shifts above EFS, and the surface becomes negatively charged. This charge-controlled reactivity is further confirmed by the superior stability of undoped p-type SnTe with EF above EFS. These distinct reactivities are explained by the surface attracting either the reactive OH- or passivating H+ ions. The present results have important implications for understanding the interaction of semiconductor surfaces with water or, in general, ionic solutions.

Research Area(s)

  • CdO, Fermi stabilization energy, moisture degradation, semiconductor stability, SnTe, surface charge determined stability, surface charge layer

Citation Format(s)

Electronically Controlled Chemical Stability of Compound Semiconductor Surfaces. / Gao, Junning; Lee, Yeonbae; Yu, Kin Man; Mao, Samuel S.; Walukiewicz, Wladek.

In: ACS applied materials & interfaces, Vol. 11, No. 35, 04.09.2019, p. 32543-32551.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalNot applicablepeer-review