Abstract :
Systematic characterization of flicker noise was conducted on GaN-based metal–semiconductor–metal (MSM) interdigitated
devices. The devices were fabricated on both the regular GaN-on-sapphire (type A) and laser de-bonded films followed by layer
transfer of hydride vapor phase epitaxy-grown GaN films to Si substrates (type B). Experimental results indicated no significant
degradation in the I–V characteristics for SchottkyMSM devices fabricated on type B films compared to those fabricated on type
A films. However, substantial increase in the flicker noise level, particularly in the low-temperature regime, is observed among
the ohmic MSM devices fabricated on type B films. The experimental data suggest that material degradation occurs at the
vicinity of the GaN–sapphire interface, while in regions close to the GaN film surface there is practically no change in the film
quality. This is supported by finite element simulation of the temperature of the film during laser irradiation. The results indicate
that the temperature dropped from 1400 K at the GaN–sapphire interface to about 1000 K within 0.5 mmaway from the interface
stipulating that material degradation occurs only within 0.5 mm from the GaN–sapphire interface
