Native levels and degradation in GaAs0.6P0.4 LEDs

New electron and hole traps in GaAsP alloy

“…Fig. 4 shows a comparison of the hole thermal emission activation energy of trap C and that observed by Lopez et al (1979). Our trap C was measured at a lower temperature.…”

“…Only a few reports (Forbes 1975, Lopez et al 1979, Hawkins and Forbes 1975 gave the observation of hole trap in GaAs 1-x P x . Hawkins and Forbes (1975) observed four levels at 0´43, 0´24, 0´13 and 0´003 eV from the valance band in GaAs 0´6 P 0´4 associated with copper impurities intentionally introduced in the samples.…”

“…Hawkins and Forbes (1975) observed four levels at 0´43, 0´24, 0´13 and 0´003 eV from the valance band in GaAs 0´6 P 0´4 associated with copper impurities intentionally introduced in the samples. Later, Lopez et al (1979) reported hole traps at 0´65, 0´41 and 0´01 eV above the valence band in their study of native level structure in VPE GaAs 0´6 P 0´4 LED. The 0´65 eV hole trap level which was measured at high temperature by capacitance transient techniques seemed to be related to the degradation process of the LED.…”

“…Defects in semiconductors play a particularly important role in materials and device properties, causing a decrease in light emission efficiency and degradation in device performance, mainly due to the formation of non-radiative recombination centres which may lie deep in the energy gap (Forbes 1975, Lopez et al 1979, Hawkins and Forbes 1975, Calleja et al 1983, Kaniewska and Kaniewski 1988, Henning and Thomas 1982, Tokuda 1987, Zhang et al 1990, Kaminski 1993, Chino 1986, Samuelson and Omling 1986, Omling et al 1983.…”