Temperature Dependencies of Free-Carrier-Absorption Lifetime in Fluorescent 6H-SiC Layers

EMRS 2013 Spring Meeting, Symposium G: Alternative approaches of SiC and related wide bandgap materials in light emitting and solar cell applications

Manolis, G.^1 ; Gulbinas, K.^1 ; Grivickas, V.^1 ; Jokubaviius, V.^2 ; Linnarsson, M.K.^3 ; Syväjärvi, M.^2

Institute of Applied Research, Vilnius University, Saultekio av. 10, LT-10223 Vilnius, Lithuania^1

Department of Physics, Chemistry and Biology, Linköping University, Linköping, SE-58183, Sweden^2

School of Information and Communication Technology, Royal Institute of Technology, SE-16440 Kista, Sweden^3

关键词: Free carrier absorption;    Hole recombination;    Nonradiative decays;    Recombination channels;    Temperature dependencies;    Thermal activation;    Visible emissions;    Wide temperature ranges;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/56/1/012006/pdf
DOI  :  10.1088/1757-899X/56/1/012006

来源: IOP

【 摘 要 】

The nonradiative decay of majority electrons has been studied over a wide temperature range from 80 K to 600 K using the time-resolved free-carrier-absorption (FCA) technique. At high injection level of the highly-luminescent N-B codoped 6H-SiC epilayer, we revealed three main relaxation components of injected free electrons over ps-to-ms time ranges. By means of temperature dependency, two components can be ascribed to thermal activation of holes from a shallow (200 meV) and a deep (500 meV) acceptor. The third one, which has a hundred us-time scale, we attribute to minority hole recombination from the valance band into the electron trap (53 meV). This recombination channel seems to compete with the deep-acceptor (Boron) to-donor (Nitrogen) pair visible emission at and below 300 K.