High-Power High-Temperature Heterobipolar TransistorWith Gallium Nitride Emitter

300°C GaN/AlGaN Heterojunction Bipolar Transistor

A GaN/AlGaN heterojunction bipolar transistor has been fabricated using Cl2/Ar dry etching for mesa formation. As the hole concentration increases due to more efficient ionization of the Mg acceptors at elevated temperatures (> 250°C), the device shows improved gain. Future efforts should focus on methods for reducing base resistance, which are briefly summarized.

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 dc current gain of 15 at room temperature and 3 at 300°C.

A Review of Dry Etching of GaN and Related Materials

The characteristics of dry etching of the AlGaInN materials system in different reactor types and plasma chemistries are reviewed, along with the depth and thermal stability of etch-induced damage. The application to device processing for both electronics and photonics is also discussed.

The Evolution of Nitride Semiconductors

The great scientific and commercial success of the group-III nitrides in recent years is the result of persistent fundamental research over a time span of three decades. In the late 60's and in the early 70's the very heart of gallium nitride research was located in J.I. Pankove's laboratory at RCA. There the first single crystalline GaN was grown by Maruska and Tietjen and the very first GaN light emitting diodes were produced by Pankove in September 1971, 26 years ago. Since then the community of nitride research has come a long and troublesome way, but it has succeeded. This 1997 Fall Meeting Symposium on Nitride Semiconductors of the Materials Research Society is dedicated to Professor J.I. Pankove for his outstanding and groundbreaking contributions in the early development of group-III nitride research. This paper reports a historical summary of the evolution of the field summarizing the landmark contributions that have led to the current status of success.