GaN HEMTs on low resistivity Si substrates with thick buffer layers for RF signal amplification and power conversion

Wenjie Song*, Jie Zhang, Zheyang Zheng, Sirui Feng, Xuelin Yang, Bo Shen, Kevin J. Chen*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)

Abstract

We report GaN high-electron-mobility transistors (HEMTs) with a thick (7.7 μm) GaN buffer on a Czochralski low resistivity Si (LRS) substrate. The GaN HEMTs exhibit high performance for both radio-frequency (RF) amplification and power conversion. The thick GaN buffer was grown by means of vacancy engineering, delivering a low dislocation density of ∼1.6 × 108 cm-2, contributing to suppressed RF signal coupling to the lossy Si substrate and a high vertical voltage blocking capability. For RF performance, GaN HEMTs with a 650 nm gate exhibit an fT/fMAX value of 25.1/32.3 GHz and a maximum output power POUT of 2.2 W/mm at 4 GHz with a drain voltage VDS of 20 V, which is comparable with the performance of RF GaN HEMTs on a high-resistivity silicon substrate without the existence of the field plate. For power performance, the vertical breakdown voltage of the wafer is 1160 V, and the three-terminal lateral breakdown voltage is 885 V in a GaN HEMT with a gate-to-drain distance of 8 μm. The thick GaN layer on the LRS substrate scheme thus provides a compelling platform for monolithic integration of high-performance RF devices and high-voltage power devices.

Original languageEnglish
Article number045125
JournalAIP Advances
Volume12
Issue number4
DOIs
Publication statusPublished - 1 Apr 2022
Externally publishedYes

Fingerprint

Dive into the research topics of 'GaN HEMTs on low resistivity Si substrates with thick buffer layers for RF signal amplification and power conversion'. Together they form a unique fingerprint.

Cite this