Nonlinear photocarrier drift in hydrogenated amorphous silicon-germanium alloys

Journal Article · Sat Jun 15 04:00:00 EDT 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.43.13957· OSTI ID:5776026

Antoniadis, H; Schiff, E A ^[1]

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1. Department of Physics, Syracuse University, Syracuse, New York 13244-1130 (US)

We have studied nonlinear effects of an electric field on the transport of both electrons and holes in a series of undoped hydrogenated amorphous silicon-germanium alloy specimens ({ital a}-Si{sub 1{minus}{ital x}}Ge{sub {ital x}}:H; 0{lt}{ital x}{lt}0.3). We measured the transient photocurrents in {ital p}-{ital i}-{ital n} diode structures as a function of electric field (10{sup 4}--2.6{times}10{sup 5} V/cm) and temperature (90--300 K). Time-of-flight and charge-collection measurements were also conducted, from which we concluded that the quantum efficiency for photocarrier generation varied less than 10% for all specimens in this temperature and electric-field range. In all cases, transport was dispersive, but we found no evidence for a field dependence in the dispersion itself. For the hydrogenated amorphous silicon specimen ({ital a}-Si:H) a field of 2{times}10{sup 5} V/cm increased the electron drift mobility by a factor of 8 at 130 K. The characteristic electric field for the onset of nonlinear electron transport increased with Ge concentration and light soaking. In {ital a}-Si:H we found slight evidence for nonlinear transport of holes.

• OSTI ID: 5776026
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 43:17; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALLOYS
AMORPHOUS STATE
CARRIER MOBILITY
CHEMICAL REACTIONS
CURRENTS
ELECTRIC CURRENTS
ELECTRIC FIELDS
GERMANIUM ALLOYS
HYDROGENATION
LOW TEMPERATURE
MEDIUM TEMPERATURE
MOBILITY
PHOTOCURRENTS
SILICON ALLOYS
TEMPERATURE DEPENDENCE