GaAs High Breakdown Voltage Front and Back Side Processed Schottky Detectors for X-Ray Detection

Abstract

We have studied the current voltage and X-ray detection using front and back side processed, unintentionally doped bulk gallium-arsenic (GaAs) Schottky detectors and determined that GaAs detectors with a large enough thickness and low enough doping could be used for X-ray imaging, especially for medical applications. In this study, GaAs Schottky detectors were fabricated using front and back side photolithographic processing using Ti/Au for Schottky and Ge/Au/Ni/Au for ohmic contacts. A number of 2 2 mm detectors were tested. The breakdown voltage reached 600 800 V in semi-insulated (SI) GaAs Schottky front and back side processed detectors. For these detectors, the dark current was found to be between 2 90 nA. These detectors were also characterized with 150 keV, 3mA X-ray radiation and they responded well, showing more than a hundred fold increase in photocurrent due to production of electron hole pairs by the ionization processes. The processing of the detectors and the current-voltage (I-V) and X-ray characterizations are presented in this report.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 2007
Accession Number
ADA484678

Entities

People

  • Fred Semendy
  • Kara Blaine
  • Mark Litz
  • Nibir Dhar
  • Priyalal Wijewarnasuriya
  • Satpal Singh

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • Biomedical

DTIC Thesaurus Topics

  • Ceramic Materials
  • Charge Carriers
  • Chemical Vapor Deposition
  • Circuit Boards
  • Compound Semiconductors
  • Detection
  • Detectors
  • Electron Holes
  • Electrons
  • Fabrication
  • Materials
  • Metal-Semiconductor Junctions
  • Radiation
  • Semiconductors
  • Thickness
  • X Rays
  • X-Ray Detectors

Fields of Study

  • Materials science

Readers

  • Nuclear and Radiation Engineering.
  • Semiconductor Device Technology

Technology Areas

  • Microelectronics