Annealing behavior of the hydrogen-vacancy complex in bulk indium phosphide crystals
- Lawrence Berkeley National Lab., CA (United States). Materials Sciences Div.
- Air Force Rome Lab., Hanscom AFB, MA (United States)
In order to explain the effects of hydrogen on the electrical properties of bulk indium phosphide crystals, they have performed a series of high temperature annealing studies with both undoped and iron-doped indium phosphide crystals. The samples were annealed at 900 C for 6, 36, and 72 hours, respectively, under a phosphorus overpressure of five atmospheres. Samples were characterized at 10 K by Fourier transform infrared absorption spectroscopy which allowed us to measure the concentrations of both the Fe{sup 2+} and V{sub In}-H{sub 4} defects simultaneously. Undoped samples were further characterized by the Hall effect measurements. The authors find in the iron-doped samples that the [Fe{sup 2+}]/[Fe{sup 3+}] ratio decreases gradually with increasing annealing time, indicating a reduction in the number of donors in the samples. In the undoped samples, annealing leads to a reduction of the free electron concentration accompanied by an increase in the 77 K mobility. The increase of the sample`s mobility eliminates the possibility that the reduction of the free electron concentration is due to an increase in the concentration of the compensating acceptors. The explanation for the observed behavior in all samples is that hydrogen acts as a donor and it diffuses out of the crystal during the annealing process. Based on the experimental data, they propose a calibration equation of [V{sub In}-H{sub 4}] = 4.2 {times} 10{sup 16} cm{sup {minus}1} {times} Absorbance (cm{sup {minus}1}) which is used to correlate the hydrogen-vacancy complex concentrations with the changes of the V{sub In}-H{sub 4} absorption peak in both the iron-doped and the undoped samples. Their results confirm the donor nature of the hydrogen-vacancy complex and provide strong evidence regarding the reduction mechanism of free carrier concentrations in bulk indium phosphide crystals during high temperature annealing under a phosphorus atmosphere.
- Sponsoring Organization:
- Department of the Air Force, Washington, DC (United States); USDOE Office of Energy Research, Washington, DC (United States)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 308114
- Report Number(s):
- CONF-980405-; TRN: IM9907%%40
- Resource Relation:
- Conference: Spring meeting of the Materials Research Society, San Francisco, CA (United States), 13-17 Apr 1998; Other Information: PBD: 1998; Related Information: Is Part Of Hydrogen in semiconductors and metals; Nickel, N.H. [ed.] [Hahn-Meitner-Inst., Berlin (Germany)]; Jackson, W.B. [ed.] [Xerox Palo Alto Research Center, CA (United States)]; Bowman, R.C. [ed.] [Jet Propulsion Lab., Pasadena, CA (United States)]; Leisure, R.G. [ed.] [Colorado State Univ., Fort Collins, CO (United States)]; PB: 469 p.; Materials Research Society symposium proceedings, Volume 513
- Country of Publication:
- United States
- Language:
- English
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