TY - JOUR
T1 - Enhanced performances of AlGaN/GaN HEMTs with dielectric engineering of HfZrOx
AU - Cui, Xiao
AU - Cheng, Weijun
AU - Hua, Qilin
AU - Liang, Renrong
AU - Hu, Weiguo
AU - Wang, Zhong Lin
N1 - Publisher Copyright:
© 2019 Elsevier Ltd
PY - 2020/2
Y1 - 2020/2
N2 - III-nitrides based high electron-mobility transistors (HEMTs) are well-known excellent candidates for high-power, radio-frequency (rf) and high-temperature applications. However, HEMTs have to face the essential issues of high gate leakage current and drain current collapse (gate-lag), which inevitably limits the device performances and reliability. Here, we fabricate an optimized AlGaN/GaN metal-oxide-semiconductor high electron mobility transistor (MOS-HEMT), by using HfZrOx (HZO) as a gate dielectric, that can improve the interfacial and transport properties. Compared to the conventional high permittivity (high-κ) gate dielectric HfO2 which has attracted wide attention in recent years, the concentrations of interface traps and the inside fixed oxide defects are obviously reduced by using high quality HZO layer. Through the dielectric engineering of HZO, the MOS-HEMT with HZO dielectric shows an enhanced DC output performance with an increase of 54% at the optimal working condition, which is indeed much higher than that of the HfO2 MOS-HEMT (40%). And the HZO MOS-HEMT exhibits a higher Ion/Ioff ratio of 106, an excellent subthreshold swing (SS) of 85 mV/decade, and a higher voltage swing (GVS). The gate leakage is reduced by nearly 8 orders of magnitude compared to the conventional unpassivated HEMTs (conv. HEMT) at the gate voltage of −5 V. These results are mainly caused by the replacement of the low-height Schottky barrier (SB) and the reduction of interface traps density. In order to further investigate the interfacial and electric properties of HZO MOS-HEMT, the dynamic gate/drain voltage and high-frequency capacitance-voltage (C–V) measurements are both applied. Remarkably, no measurable current collapse and C–V hysteresis are clearly observed, showing the enhanced interfacial and electric performances of the MOS-HEMT with dielectric engineering of HZO.
AB - III-nitrides based high electron-mobility transistors (HEMTs) are well-known excellent candidates for high-power, radio-frequency (rf) and high-temperature applications. However, HEMTs have to face the essential issues of high gate leakage current and drain current collapse (gate-lag), which inevitably limits the device performances and reliability. Here, we fabricate an optimized AlGaN/GaN metal-oxide-semiconductor high electron mobility transistor (MOS-HEMT), by using HfZrOx (HZO) as a gate dielectric, that can improve the interfacial and transport properties. Compared to the conventional high permittivity (high-κ) gate dielectric HfO2 which has attracted wide attention in recent years, the concentrations of interface traps and the inside fixed oxide defects are obviously reduced by using high quality HZO layer. Through the dielectric engineering of HZO, the MOS-HEMT with HZO dielectric shows an enhanced DC output performance with an increase of 54% at the optimal working condition, which is indeed much higher than that of the HfO2 MOS-HEMT (40%). And the HZO MOS-HEMT exhibits a higher Ion/Ioff ratio of 106, an excellent subthreshold swing (SS) of 85 mV/decade, and a higher voltage swing (GVS). The gate leakage is reduced by nearly 8 orders of magnitude compared to the conventional unpassivated HEMTs (conv. HEMT) at the gate voltage of −5 V. These results are mainly caused by the replacement of the low-height Schottky barrier (SB) and the reduction of interface traps density. In order to further investigate the interfacial and electric properties of HZO MOS-HEMT, the dynamic gate/drain voltage and high-frequency capacitance-voltage (C–V) measurements are both applied. Remarkably, no measurable current collapse and C–V hysteresis are clearly observed, showing the enhanced interfacial and electric performances of the MOS-HEMT with dielectric engineering of HZO.
KW - AlGaN/GaN
KW - Dielectric
KW - HEMT
KW - HfZrO
KW - High-κ
UR - http://www.scopus.com/inward/record.url?scp=85076134985&partnerID=8YFLogxK
U2 - 10.1016/j.nanoen.2019.104361
DO - 10.1016/j.nanoen.2019.104361
M3 - Article
AN - SCOPUS:85076134985
SN - 2211-2855
VL - 68
JO - Nano Energy
JF - Nano Energy
M1 - 104361
ER -