Open AccessA Low Program Voltage Enabled Flash like AlGaN/GaN Stack Layered MIS-HEMTs Using Trap Assisted Technique
Author(s) -
Soumen Mazumder,
Parthasarathi Pal,
Ting Jia Tsai,
Pu Lin,
Yeong-Her Wang
Publication year - 2021
Publication title -
ecs journal of solid state science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.488
H-Index - 51
eISSN - 2162-8777
pISSN - 2162-8769
DOI - 10.1149/2162-8777/ac02a1
Subject(s) - materials science , optoelectronics , high electron mobility transistor , threshold voltage , gate dielectric , leakage (economics) , transistor , analytical chemistry (journal) , voltage , electrical engineering , economics , macroeconomics , engineering , chemistry , chromatography
In this paper, a flash like Al 2 O 3 /SiO 2 stacked layer AlGaN/GaN-based metal insulator semiconductor high electron mobility transistor (MIS-HEMT) was fabricated using trap assisted technique. The MIS-HEMT showed a large positive shifting of threshold voltage (∆V TH ) of 4.6 V after applying a low program voltage (V P ) of 3 V, resulting in a very low threshold voltage of −0.3 V with a decent maximum drain current (I DMAX ) of 575 mA mm −1 . A ultraviolet-ozone (UV/O 3 ) surface treatment was done prior to gate dielectric deposition to produce a thin gallium oxynitride (GaO X N Y ) layer at GaN/oxide interface, which correspondingly acts as a charge trapping layer, resulting in the reduction in V P . The capacitance-voltage (C–V) measurements revealed that the traps contributing to the significant positive shifting of V TH had a density of 5.7 × 10 12 cm −2 . These traps were attributed to the border or oxide defects. A significant reduction in gate leakage current (I G ) of more than three orders of magnitude was found in MIS-HEMT, due to the high quality Al 2 O 3 /SiO 2 stack gate dielectric layer compared to conventional HEMT. The flash like stack layered programmed MIS-HEMT exhibited a G MMAX of 123 mS mm −1 , on-off ratio of 1.7 × 10 7 , subthreshold slope of 121 mV dec −1 with a reduced gate leakage current of 7.5 × 10 −9 A mm −1 .