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Fabrication of magnesium-doped gallium nitride nanorods and microphotoluminescence characteristicsKinetics of low-temperature activation of acceptors in magnesium-doped gallium nitride epilayers grown by metal-organic vapor-phase epitaxy Electrical characteristics of lateral p ϩ n diodes made from gallium nitride epitaxial layers on sapphire substrates are reported. The current-voltage characteristics are observed to have several distinct regions in which a tunneling current has been identified at low forward bias in addition to the conventional temperature-dependent diffusion current observed at moderate forward bias. A tunneling behavior indicates the presence of deep-level traps at the junction, which alter the electrical behavior of these junctions compared to the conventional behavior. In addition, space-charge-limited currents are found to influence these junctions at large forward and reverse bias.

The present status of plasma etching of refractory gates is reviewed in the context of high resolution patterning. Etching of various refractory metals (cf. Mo, W) and metal silicides (cf. MoSi2 , WSi2 , TaSi2 ) is particularly emphasized and discussed in terms of etch rate, anisotropy, etch selectivity over SiO2 , resist, and other thin film materials. Key issues addressed include choice of etchant (cf. CF4 , NF3 , CCl4 ), additive gas ( O2 , Ar, He), and reactor configuration (planar plasma, RIE, flexible diode, triode). Factors influencing the control of edge profiles in single‐level and composite gate structures are described. End‐point detection of these plasma processes is reviewed and compared with that developed for silicon etching. Also, basic mechanisms in these processes, such as desorption of reaction products, are discussed with respect to their effect on the etching characteristics of these refractory materials.

In this paper, we have investigated the high temperature characteristics of monolithically integrated LED and MOSchannel HEMT in GaN. The monolithically integrated LED/MOSC-HEMT was implemented by using a selective epi removal approach. The temperature dependence of optical and electrical characteristics of the integrated LED is found to be comparable to that of discrete GaN based LEDs.On-resistance of the MOSC-HEMT shows gradual increase with temperature (~1.6Â increase from 25 8C to 225 8C) whereas LED LOP shows rapid decrease with temperature (~6Â decrease from 25 8C to 225 8C). Light output of the integrated LED is modulated by the MOSC-HEMT gate bias up to 225 8C.