Improvement in GaAs Device Yield and Performance through Substrate Defect Gettering.
Abstract
The use of mechanically produced back-surface-damage as a means of gettering impurities and defects in GaAs wafers has been investigated. Comparative analyses have been done on both ion implantation and mechanical back-surface-damage gettering techniques. The increased thermal stability of mechanically produced damage has shown ion implantation techniques to be less effective for gettering over long anneal periods at elevated temperatures. For anneals at 800 C for periods less than 5 hrs, stress gradients produced by graded dislocation distributions produce reductions in front surface defect concentrations and effective gettering of Au and Cr at the back surface. For anneal times exceeding the thermal stability time reverse gettering or impurity detrapping occurs at the back surface. Front-surface encapsulating layers have also been shown to exercise a small but perceptible effect related in part to the concentration of As and/or Ga vacancies in the interfacial region. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1978
- Accession Number
- ADA060728
Entities
People
- Jing Peng
- Jonathan Hong
- R. A. Armistead
- T. J. Magee