Improved Ultraviolet Detection and Device Performance of Al₂O₃-Dielectric In_0.17Al_0.83N/AlN/GaN MOS-HFETs

Abstract

Ultraviolet (UV) detection and electrical characteristics of In 0.17 Al 0.83 N/AlN/GaN metaloxide-semiconductor heterostructure field-effect transistors (MOS-HFETs) with Al 2 O 3 gate-dielectric and passivation formed by using ultrasonic spray pyrolysis deposition (USPD) are studied with respect to a conventional Schottky-gate HFET. The present MOS-HFET (Schottky-gate HFET) has demonstrated superior spectral responsivity (SR) of 360 (340) A/W at 350 nm at V GS = 5(3) V and V DS = 6(7) V, maximum drain-source saturation current density (I DS,max ) of 810.5 (546.6) mA/mm, maximum extrinsic transconductance of (g m,max ) of 180.4 (221.2) mS/mm, gate-voltage swing (GVS) of 2.4 (0.5) V, on/off current ratio (I on /I off ) of 5.5 × 10 8 (1.7 × 10 5 ), two-terminal off-state gate-drain breakdown voltage (BV GD ) of −158.5 (−127) V, three-terminal drain-source breakdown voltage (BV DS ) of 162 (83.4) V at V GS = −10 V, and power-added efficiency (P.A.E.) of 26.3% (16.5%) at 2.4 GHz at 300 K. In addition to the improved device performance, this paper demonstrates, for the first time, the UV sensing based on an InAlN/AlN/GaN MOS-HFET design.

Improved Electrical and Deep-UV Sensing Characteristics of Al2O3-Dielectric AlGaN/AlN/SiC MOS-HFETs

“…The obtained maximum SR of the present MOS-HFET is also superior to other devices at similar radiation wavelengths. [36][37][38][39] In addition to the g m gain provided by the present MOS-HFET design, the widegap Al…”

Analysis of High-Frequency Behavior of AlGaN/GaN HEMTs and MIS-HEMTs under UV Illumination

“…In order to avoid these drawbacks, photodetectors with HEMT and metal-insulator-semiconductor HEMT (MIS-HEMT) structures were adopted. [10][11][12] The HEMT and MIS-HEMT devices show high dc responsivity to the UV light. With a highly conductive two-dimensional electron gas (2-DEG) channel at the AlGaN/GaN interface and the associated short transit time under the gate, GaN-based HEMTs can have high internal gain compared with other UV detectors based on diode structure.…”

“…The dc and transient characteristics of GaN-based HEMTs under UV illumination have been investigated widely to demonstrate the photoconductivity and spectral responsivity as well as to explore the charge trapping phenomena in devices. [10][11][12][13][14][15] However, the highfrequency behavior of GaN-based HEMTs under UV illumination was less discussed. With the high optical response and excellent microwave performance, GaN-based devices should be suitable for using in optically controlled and optically switched integrated circuits.…”

Al0.75Ga0.25N/AlxGa1-xN/Al0.75Ga0.25N/AlN/SiC Metal–Oxide–Semiconductor Heterostructure Field-Effect Transistors With Symmetrically-Graded Widegap Channel

“…Superior SR performances of 1780 A/W and 810.2 A/W have been achieved for the deep-UV radiation wavelengths of 250 nm and 300 nm, respectively. The present UV sensing performance is superior to 360 A/W at λ = 350 nm of InAlN/AlN/GaN MOS-HFET [28], 34 A/W at λ = 367 nm of InAlN/GaN stack photodiode (PD) [31], and other PDs [32]- [33]. Excellent SR was contributed by the device gain and noise immunity of the widegap AlGaN channel of the present design.…”