Study of Grown-In Defects Verses Growth Parameters in GaAs and Al(x)Ga(1-x)AS Epitaxial Films Grown by LPE and MOCVD Techniques.
Abstract
A model for describing the physical origins of the EL2 center in the GaAs is presented based on the kinetic reaction equations and the analysis of electric-field enhanced emission rates for the four different types of potential well. It has been shown that the EL2 center may be ascribed to two different types of native defect: One level (E sub c-0.83 eV) attributing to the antisite defect, As sub Ga or the antisite cluster, As sub Ga-As4 is designated as the EL2a electron trap, and the other level ( E sub c-0.76 eV) attributing to the antisite-vacancy complex, As sub Ga-VAs is designated as the EL2b electron trap. The EL2a electron trap was found to be strongly dependent on the growht condition, e.g.,AsH3/TMGa ratio, growth temperature growth rate(mainly at lower growth rate) and buffer layer. Second, the final transition state of electron emission from the DX center to the nonspherical conduction band minima in A1xGa1-xAs has been studied by capacitance-Voltage measurement and Deep level Transient Spectroscopy experiment. The results indicate that the conduction band minimum associated with the electron emission is the L band instead of the band which is the lowest conduction band. Analysis of th eelectric-field enhanced emission rate applied to the Coulombic and Yukawa potential well has further supported the fact that emission and capture of electron from the DX center is related to the L minimum in the conduction band.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 15, 1985
- Accession Number
- ADA173736
Entities
People
- Shengsan Li
Organizations
- University of Florida