Photoquenching effect and thermal recovery process for midgap levels in GaAs: An EL2 family in GaAs

Hoon Young Cho, Eun Kyu Kim, Suk Ki Min

Research output: Contribution to journalArticlepeer-review

13 Scopus citations

Abstract

We have studied the photocapacitance quenching effect and the thermal recovery process for the EL2 family in heat-treated GaAs. During the heat treatment at 850°C with use of an infrared rapid thermal process, it was identified that EL2, as the main midgap-level defect in GaAs, does not exist alone, but three different midgap levels at 0.73, 0.81, and 0.87 eV below the conduction band coexist with it as a family in various proportions. The EL2 out-diffusion coefficient of 1.02×10-8 cm2/s indicates that EL2 should have a contribution from an interstitial arsenic atom (Asi). These three midgap levels represent a nonexponential quenching transient at 77 K and three activation energies (150, 300, and 350 meV) of the thermal recovery process. Our data indicate that three midgap levels in GaAs make up the EL2 family, each involving a different metastable state. We suggest that three kinds of EL2 could each have their own metastable states and coexist as a family. We conclude that, if EL2 has the atomic structure of AsGa+X, X might be an interstitial arsenic atom (Asi) or a vacancy complex with Asi..AE

Original languageEnglish
Pages (from-to)10376-10379
Number of pages4
JournalPhysical Review B
Volume39
Issue number14
DOIs
StatePublished - 1989

Fingerprint

Dive into the research topics of 'Photoquenching effect and thermal recovery process for midgap levels in GaAs: An EL2 family in GaAs'. Together they form a unique fingerprint.

Cite this