High-Temperature Annealing of Sputter-Deposited AlN on Diamond Substrate

Diamond is an attractive widegap semiconductor for power devices due to the bandgap of 5.5 eV and high hole conductivity. Quantum sensing by nitrogen-vacancy (NV) centers has also been focused on in recent years. On the other hand, (Al, Ga)N has been extensively studied for deep ultraviolet LEDs and high electron mobility transistors, whereas the poor p-type conductance limits the performance of bipolar devices. Hence, the heterogeneous integration of diamond and (Al, Ga)N is expected to realize efficient carrier injection into widegap bipolar devices.