Print Email Facebook Twitter Enhanced Sensitivity Pt/AlGaN/GaN Heterostructure NO Sensor Using a Two-Step Gate Recess Technique Title Enhanced Sensitivity Pt/AlGaN/GaN Heterostructure NO Sensor Using a Two-Step Gate Recess Technique Author Sun, J. (TU Delft Electronic Components, Technology and Materials; Tsinghua University) Zhan, Teng (Chinese Academy of Sciences) Sokolovskij, R. (Southern University of Science and Technology) Liu, Zewen (Tsinghua University) Sarro, Pasqualina M (TU Delft Electronic Components, Technology and Materials) Zhang, Kouchi (TU Delft Electronic Components, Technology and Materials) Date 2021 Abstract 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. The sensitivity and current change of the AlGaN/GaN heterostructure to 1-200 ppm NO2/air are increased up to about 20 and 12 times compared to conventional gate device, respectively. The response time is also reduced to only about 25 % of value for conventional device. The sensor has a suspended circular membrane structure and an integrated micro-hotplate for adjusting the optimum working temperature. The sensitivity (response time) increases from 0.75 % (1250 s) to 3.5 % (75 s) toward 40 ppm NO2/air when temperature increase from 60°C to 300°C. The repeatability and cross-sensitivity of the sensor are also demonstrated. These results support the practicability of a high accuracy and fast response gas sensor based on the suspended gate recessed AlGaN/GaN heterostructure with an integrated micro-heater. Subject AlGaN/GaNNOgas sensorgate recess To reference this document use: http://resolver.tudelft.nl/uuid:d975bb25-2946-42ee-8efe-23f2fc1203a4 DOI https://doi.org/10.1109/JSEN.2021.3082205 Embargo date 2021-11-30 ISSN 1530-437X Source IEEE Sensors Journal, 21 (15), 16475-16483 Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2021 J. Sun, Teng Zhan, R. Sokolovskij, Zewen Liu, Pasqualina M Sarro, Kouchi Zhang Files PDF Enhanced_Sensitivity_Pt_A ... hnique.pdf 2.65 MB Close viewer /islandora/object/uuid:d975bb25-2946-42ee-8efe-23f2fc1203a4/datastream/OBJ/view