Title :
Mobility-lifetime products for electrons and holes in 1.75 eV-1.95 eV a-SiC:H films
Author :
Mohring, H.-D. ; Schumm, G. ; Bauer, G.H.
Author_Institution :
Inst. fuer Phys. Elektronik, Stuttgart Univ., Germany
Abstract :
Intrinsic a-SiC:H thin films with optical bandgaps Eg⩽1.95 eV have been prepared by SiH4/CH4 DC glow discharge in an ultra-high-vacuum deposition system [(total leak+desorption rate)/(gas flow)⩽2×10-8] with power densities below 50 mW/cm 2. The deposition process has been optimized with respect to maximum network relaxation indicated by minimum PDS Urbach energy E 0. It is shown that the carbon induced slight decrease of hole μτ product (factor 5) reflects the enlarged density of recombination centers whereas the strong decrease of electron μτ product (factor 50) is due to the additionally enhanced density of deep electron traps
Keywords :
amorphous semiconductors; carrier lifetime; carrier mobility; electrical conductivity of amorphous semiconductors and insulators; electron traps; electron-hole recombination; hydrogen; plasma deposition; semiconductor doping; semiconductor thin films; silicon compounds; vacuum deposition; 1.75 to 1.95 eV; SiC:H; amorphous semiconductor thin films; deep electron traps; electrons; glow discharge; holes; mobility-lifetime products; network relaxation; optical bandgaps; plasma deposition; power densities; recombination centers; vacuum deposition; Bonding; Charge carrier processes; Conductivity; Electron mobility; Optical buffering; Optical films; Photoconductivity; Photonic band gap; Pollution measurement; Steady-state;
Conference_Titel :
Photovoltaic Specialists Conference, 1991., Conference Record of the Twenty Second IEEE
Conference_Location :
Las Vegas, NV
Print_ISBN :
0-87942-636-5
DOI :
10.1109/PVSC.1991.169429
