Dual Current and Voltage Sensitivity Temperature Sensor Based on Lateral p-GaN/AlGaN/GaN Hybrid Anode Diode
Xing Wei, Xiaodong Zhang, Xin Zhou, Yongjian Ma, Wenbo Tang, Tiwei Chen, Weining Liu, Wenxin Tang, Guohao Yu, Yaming Fan, Kai Fu, Yong Cai, Baoshun Zhang
Abstract
In this work, a p-GaN/AlGaN/GaN hybrid anode diode (HAD) temperature sensor was fabricated by using hydrogen plasma treatment. The zero-temperature coefficient (ZTC) is about 0.7 V from the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}$ </tex-math></inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}$ </tex-math></inline-formula> characteristics measured at various temperatures. At the forward region below the ZTC bias point, the anode voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{{\mathrm {A}}}$ </tex-math></inline-formula> ) at a specific anode current density ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{{\mathrm {A}}}$ </tex-math></inline-formula> ) decreases linearly with the increase of temperature, resulting in a sensitivity ranging from 1.64 mV/K (10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−5</sup> mA/mm) to 0.69 mV/K (10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−2</sup> mA/mm). The leakage current at the reverse bias also presents a temperature-dependent behavior with a sensitivity ranging from 16.76 mA/K (−100 V) to 27.94 mA/K (−5 V). The experimental results can be interpreted well by the two-dimensional variable range hopping model.