A GaN/4H-SiC heterojunction bipolar transistor with operation up to 300°C

We report on the fabrication and characterization of GaN/4H-SiC n-p-n heterojunction bipolar transistors (HBTs). The device structure consists of an n-SiC collector, p-SiC base, and selectively grown n-GaN emitter. The HBTs were grown using metalorganic chemical vapor deposition on SIC substrates. Selective GaN growth through a SiO2 mask was used to avoid damage that would be caused by reactive ion etching. In this report, we demonstrate common base transistor operation with a modest de current gain of 15 at room temperature and 3 at 300 degrees C.