Title :
Microwave Power Performance N-Polar GaN MISHEMTs Grown by MOCVD on SiC Substrates Using an
Etch-Stop Technology
Author :
Kolluri, Seshadri ; Keller, Stacia ; DenBaars, Steven P. ; Mishra, Umesh K.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of California, Santa Barbara, CA, USA
Abstract :
This letter presents the RF power performance of N-polar AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MISHEMTs) grown by metal-organic chemical vapor deposition (MOCVD) on semi-insulating SiC substrates at 10 and 4 GHz. Additionally, an Al2 O3-based etch-stop technology was demonstrated for improving the manufacturability of N-polar GaN HEMTs with SixNy passivation. The reported output power densities of 16.7 W/mm at 10 GHz and 20.7 W/mm at 4 GHz represent the highest reported values so far for an N-polar device, at both of these frequencies. The improvements achieved in the RF output power density when compared with previously reported N-polar MISHEMTs can be attributed to high breakdown voltage of N-polar devices grown by MOCVD and high thermal conductivity of the SiC substrate.
Keywords :
MOCVD; aluminium compounds; gallium compounds; high electron mobility transistors; passivation; semiconductor device breakdown; silicon compounds; thermal conductivity; wide band gap semiconductors; Al2O3; AlGaN-GaN; GaN; MOCVD; N-polar MISHEMT; N-polar metal-insulator-semiconductor high-electron-mobility transistors; RF power performance; breakdown voltage; etch-stop technology; frequency 10 GHz; frequency 4 GHz; metal-organic chemical vapor deposition; passivation; semi-insulating substrates; thermal conductivity; Aluminum gallium nitride; Gallium nitride; HEMTs; Logic gates; MOCVD; Performance evaluation; Substrates; C-band; GaN; N-polar; X-band; high-electron-mobility transistor (HEMT); metal–organic chemical vapor deposition (MOCVD);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2011.2173458