Electrical analyses of GaN PIN diodes grown on patterned sapphire substrates

In this article, the authors report the fabrication and characterization of quasivertical GaN p-i-n diodes with a 3 mu m I-layer grown on different sizes of patterned sapphire substrates (PSSs). The diodes were characterized by current-voltage, capacitance-voltage, and deep-level transient spectroscopy. The PIN diodes grown on the smaller-size PSS showed a reverse breakdown voltage of similar to 610V and a defect concentration of 1.0 x 10(16) cm(-3), both of which are superior to the corresponding measurements of similar to 410V and 1.4 x 10(17) cm(-3) for the diodes grown on the larger-size PSS. These results indicate that the GaN PIN diodes grown on smaller-size PSS have a better quality of epitaxial layers than those grown on larger-size PSS. (C) 2017 American Vacuum Society.