3.2 mΩcm² enhancement‐mode GaN MOSFETs with breakdown voltage of 800 V

Abstract

Enhancement‐mode GaN metal‐oxide‐semiconductor field‐effect transistors (MOSFETs) have been reported. We utilized the atomic layer deposition (ALD) method for the fabrication process of the gate dielectric, in order to suppress plasma damage and obtain high‐quality dielectric film. In the fabricated devices, the specific on‐state resistance of 3.2 mΩcm2 and the breakdown voltage of 800 V were achieved. Moreover, a 10‐year lifetime with a cumulative failure rate of 0.1% was guaranteed at over 20 V. This voltage was twice the operation voltage of 10 V. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Design and demonstration of EID MOS-HEMTs on Si substrate with normally depleted AlGaN/GaN epitaxial layer

“…To realize E-mode operations in AlGaN/ GaN HEMTs, which are depletion-mode (D-mode) transistors, [1][2][3][4][5][6][7][8] various structures have been proposed recently. [9][10][11][12][13][14][15][16][17][18][19][20][21] One such structure employs a p-type (Al)GaN layer under a gate contact and has already been commercialized. [9][10][11][12] However, the fabrication processes of these HEMTs require dry etching processes for p-(Al)GaN layers.…”

“…22) Another candidate for E-mode HEMTs with a recessed gate structure also faces similar degradation and nonuniformity because they are fabricated using dry etching processes. [13][14][15][16][17][18] Although inducing negative fluorine charges under gate contacts is another technique for realizing E-mode operation, [19][20][21] the stabilities of the resulting HEMTs may be deteriorated by traps that are unintentionally generated by the irradiation using fluorine gas plasma. 23) Therefore, current applications of E-mode GaN HEMTs are limited to relatively low-power fields such as AC/DC adapters for compact appliances.…”

Suppression of short-channel effects in normally-off GaN MOSFETs with deep recessed-gate structures

“…In normally-off GaN MOSFETs, the recessed-gate structure has been studied by removing the AlGaN barrier layer under the gate. [12][13][14][15][16][17] This structure may have the problem of high channel resistance (R ch ), due to low electron mobility in the recessed region. Since the shorter gate-length (L g ) structure is proposed to reduce R ch , there are concerns regarding degradation of drain-induced barrier lowering (DIBL) and subthreshold swing (SS) and the potential for negative threshold voltage (V th ) shift owing to short-channel effects (SCEs).…”

Improvement of Channel Mobility of GaN‐MOSFETs With Thermal Treatment for Recess Surface

“…Recessed‐gate GaN‐MOSFETs is one of the attracting structures in order to achieve enhancement‐mode operation. There are some reports on the recessed‐gate MOSFETs with several gate dielectric materials . This structure has some advantageous features.…”