Density-dependent electron transport and precise modeling of GaN high electron mobility transistors
Abstract
We report on the direct measurement of two-dimensional sheet charge density dependence of electron transport in AlGaN/GaN high electron mobility transistors (HEMTs). Pulsed IV measurements established increasing electron velocities with decreasing sheet charge densities, resulting in saturation velocity of 1.9 × 107 cm/s at a low sheet charge density of 7.8 × 1011 cm−2. An optical phonon emission-based electron velocity model for GaN is also presented. It accommodates stimulated longitudinal optical (LO) phonon emission which clamps the electron velocity with strong electron-phonon interaction and long LO phonon lifetime in GaN. A comparison with the measured density-dependent saturation velocity shows that it captures the dependence rather well. Finally, the experimental result is applied in TCAD-based device simulator to predict DC and small signal characteristics of a reported GaN HEMT. Good agreement between the simulated and reported experimental results validated the measurement presented in this report and established accurate modeling of GaN HEMTs.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 12, 2015
- Source ID
- 10.1063/1.4933181
Entities
People
- Eduardo M. Chumbes
- Fatih Akyol
- Jacob B Khurgin
- Omor Shoron
- Pil Sung Park
- Sanyam Bajaj
- Shahed Reza
- Siddharth Rajan
- Sriram Krishnamoorthy
- Ting-hsiang Hung
Organizations
- Johns Hopkins University
- Office of Naval Research
- Ohio State University
- RTX