- document
-
Yang, Chenyang (author), Sun, Jianwen (author), Zhang, Yulong (author), Tang, Jingya (author), Liu, Zizheng (author), Zhan, Teng (author), Wang, Dian-Bing (author), Zhang, Kouchi (author), Liu, Zewen (author), Zhang, Xian-En (author)The COVID-19 pandemic has highlighted the need for rapid and sensitive detection of SARS-CoV-2. Here, we report an ultrasensitive SARS-CoV-2 immunosensor by integration of an AlGaN/GaN high-electron-mobility transistor (HEMT) and anti-SARS-CoV-2 spike protein antibody. The AlGaN/GaN HEMT immunosensor has demonstrated the capability to detect...journal article 2024
- document
-
Sun, J. (author), Zhan, Teng (author), Sokolovskij, R. (author), Liu, Zewen (author), Sarro, Pasqualina M (author), Zhang, Kouchi (author)Based on our proposed precision two-step gate recess technique, a suspended gate-recessed Pt/AlGaN/GaN heterostructure gas sensor integrated with a micro-heater is fabricated and characterized. The controllable two-step gate recess etching method, which includes O2 plasma oxidation of nitride and wet etching, improves gas sensing performance....journal article 2021
- document
-
Sun, J. (author), Hu, D. (author), Liu, Zewen (author), Middelburg, L.M. (author), Vollebregt, S. (author), Sarro, Pasqualina M (author), Zhang, Kouchi (author)A micro-scale pressure sensor based on suspended AlGaN/GaN heterostructure is reported with non-linear sensitivity. By sealing the cavity, vacuum sensing at various temperatures was demonstrated. To validate the proposed concept of the AlGaN/GaN vacuum sensor, a 700 µm diameter circular membrane was electrically characterized under applied...journal article 2020
- document
-
Zhang, Jian (author), Sokolovskij, R. (author), Chen, Ganhui (author), Zhu, Yumeng (author), Qi, Yongle (author), Lin, Xinpeng (author), Li, Wenmao (author), Zhang, G. (author), Jiang, Yu-Long (author), Yu, Hongyu (author)In this paper, a method to extend the detection range of hydrogen sulfide (H<sub>2</sub>S) gas sensor is demonstrated. The sensor is based on AlGaN/GaN high electron mobility transistors (HEMTs) with Pt gate. It is observed that the as-fabricated devices exhibited sensing signal saturation at 30 ppm H<sub>2</sub>S exposure in dry air. A pre...journal article 2019
- document
-
Sun, J. (author), Sokolovskij, R. (author), Iervolino, E. (author), Santagata, F. (author), Liu, Zewen (author), Sarro, Pasqualina M (author), Zhang, Kouchi (author)A suspended AlGaN/GaN high electron mobility transistor (HEMT) sensor with a tungsten trioxide (WO 3 ) nanofilm modified gate was microfabricated and characterized for ppm-level acetone gas detection. The sensor featured a suspended circular membrane structure and an integrated microheater to select the optimum working temperature. High working...journal article 2019
- document
-
Sokolovskij, R. (author), Zhang, Jian (author), Iervolino, E. (author), Zhao, Changhui (author), Santagata, F. (author), Wang, F. (author), Yu, Hongyu (author), Sarro, Pasqualina M (author), Zhang, Kouchi (author)AlGaN/GaN high electron mobility transistor (HEMT)-based sensors with catalytic platinum gate were micro-fabricated on commercially available epitaxial wafers and extensively characterized for ppm level hydrogen sulfide (H<sub>2</sub>S) detection for industrial safety applications. High operating temperature above 150 °C enabled large signal...journal article 2018
- document
-
Precision Recess of AlGaN/GaN with Controllable Etching Rate Using ICP-RIE Oxidation and Wet EtchingSokolovskij, R. (author), Sun, J. (author), Santagata, F. (author), Iervolino, E. (author), Li, S. (author), Zhang, G.Y. (author), Sarro, Pasqualina M (author), Zhang, Kouchi (author)A method for highly controllable etching of AlGaN/GaN for the fabrication of high sensitivity HEMT based sensors is developed. The process consists of cyclic oxidation of nitride with O<sub>2</sub> plasma using ICP-RIE etcher followed by wet etching of the oxidized layer. Previously reported cyclic oxidation-based GaN etching obtained very...journal article 2016