Wireless hydrogen sensor network using AlGaN/GaN high electron mobility transistor differential diode sensors

Recent advances in wide bandgap semiconductor biological and gas sensors

“…These sensors are required to detect hydrogen near room temperature with minimal power consumption and weight and with a low rate of false alarms. Due to their low intrinsic carrier concentrations, GaN-and SiC-based wide band gap semiconductor sensors can be operated at lower current levels than conventional Si-based devices and offer the capability of detection to $600°C [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36].…”

A new type photodiode: p-Si/GaN pn junction in series with GaN/Ag Schottky diode

“…Gallium nitride (GaN), a wide direct band gap semiconductor, has attracted considerable academic as well as industrial attention for their potential applications in light-emitting devices, high mobility transistors, field effect transistors [1][2][3][4][5]. The junction properties of these devices depends on several parameters such as surface properties of the GaN film, formation of insulating layer between GaN and silicon wafer, doping level of semiconductors, density of interface states and defects.…”

Moisture Insensitive PMMA Coated Pt-AlGaN/GaN Diode Hydrogen Sensor and Its Thermal Stability

“…25 The AlGaN/GaN heterostructure based Schottky diodes have low concentration detection sensitivities (hundreds of ppm at room temperature), which is well below the concentration at which hydrogen is combustible in the air (4.65%). 3,7,16,17,24 The role of the catalytic metal is to dissociate molecular hydrogen to atomic form, leading to an adsorbed dipole layer at the metal-semiconductor interface. 8,10,15,[26][27][28][29] This leads to a reduction of the Schottky barrier height, which in turn modulates the current flowing in the device at a fixed operating voltage.…”