Buried channel normally-off AIGaN/GaN MOS-HEMT with a p-n junction in GaN buffer

Soman, Rohith and Sharma, Manish and Ramesh, Nayana and Nath, Digbijoy and Muralidharan, R and Bhat, KN and Raghavan, Srinivasan and Bhat, Navakanta (2018) Buried channel normally-off AIGaN/GaN MOS-HEMT with a p-n junction in GaN buffer. In: SEMICONDUCTOR SCIENCE AND TECHNOLOGY, 33 (9).

PDF Sem_Sci_Tec_33-9_095006_2018.pdf - Published Version Restricted to Registered users only Download (1MB) | Request a copy

Abstract

A buried channel normally-off AlGaN/GaN MOS-HEMT with gate recess etching is reported. The buried channel operation is achieved by in situ doping of GaN to introduce a p-n junction in the GaN buffer. The fabricated buried channel MOS-HEMT with 12.5 nm atomic layer deposition (ALD) Al2O3 gate dielectric featured a threshold voltage of 1.3 V with a drain saturation current of 287 mA mm(-1) for a device with 3.5 mu m long gate length and 11 mu m sourcedrain spacing. The field effect mobility improved from 25 cm(2)/Vs for a reference device to 142 cm(2)/Vs for the buried channel device. Due to the presence of the p-n junction depletion region in the GaN buffer, the leakage in the off state decreased by about 4 orders of magnitude (4 nA mm(-1) compared to 76 uA mm(-1) for the reference device). The buried channel device also gives better breakdown characteristics, with a breakdown voltage of 158 V compared to 98 V for the reference device.

Item Type:	Journal Article
Publication:	SEMICONDUCTOR SCIENCE AND TECHNOLOGY
Publisher:	IOP PUBLISHING LTD, TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
Additional Information:	Copyright of this article belong to IOP PUBLISHING LTD, TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
Department/Centre:	Division of Chemical Sciences > Materials Research Centre Division of Electrical Sciences > Electrical Communication Engineering Division of Interdisciplinary Sciences > Centre for Nano Science and Engineering
Date Deposited:	20 Aug 2018 15:36
Last Modified:	25 Feb 2019 11:19
URI:	http://eprints.iisc.ac.in/id/eprint/60464

Actions (login required)

View Item