Electron and hole dynamics in amorphous silicon

Journal Article · Fri Jul 01 04:00:00 EDT 1988 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.341465· OSTI ID:5184660

Werner, A; Kunst, M

Charge carrier dynamics in doped and undoped hydrogenated amorphous silicon (a-Si:H) films is studied by contactless time-resolved photoconductivity measurements. Subband-gap and above band-gap excitation are used to generate excess mobile charge carriers. In undoped a-Si:H the electron decay at charge carrier concentrations larger than 10/sup 16/ cm/sup -3/ is mainly due to an electron-hole recombination which is controlled by hole dispersion. n doping introduces hole traps which increase the effective electron lifetime drastically as they quench this electron-hole recombination channel. At high n-doping levels the electron decay becomes faster due to an increase of the concentration of recombination centers upon doping. In lightly doped p-type samples the transient photoconductivity reflects the interaction of mobile holes with states in the valence-band tail. In heavily doped p- and n-type films the majority carriers decay by a second-order recombination process with trapped minority charge carriers. The transport parameters deduced agree with time-of-flight data.

• Research Organization: Hahn-Meitner-Institut, Bereich Strahlenchemie, D-1000 Berlin 39, Federal Republic of Germany
• OSTI ID: 5184660
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 64:1; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
AMORPHOUS STATE
CHARGE CARRIERS
CHEMICAL REACTIONS
DATA
DYNAMICS
ELECTRON MOBILITY
ELECTRON-HOLE COUPLING
ELEMENTS
EXPERIMENTAL DATA
FILMS
HEATING
HOLE MOBILITY
HYDROGENATION
INFORMATION
LASER-RADIATION HEATING
LASERS
MECHANICS
MEDIUM TEMPERATURE
MOBILITY
NEODYMIUM LASERS
NUMERICAL DATA
PARTICLE MOBILITY
PLASMA HEATING
SEMIMETALS
SILICON
SOLID STATE LASERS
THIN FILMS