{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T12:54:24Z","timestamp":1770555264583,"version":"3.49.0"},"reference-count":33,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2017,8,22]],"date-time":"2017-08-22T00:00:00Z","timestamp":1503360000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, an electrical-based NH3 sensor with an Al\/p-Si\/Al structure is reported. The p-Si substrate is microstructured by fs-laser irradiation and then etched by 30% alkaline solution. This sensor works well at room temperature with fast response\/recovery for NH3 gas at 5\u2013100 ppm concentration. However, when the sensor is annealed in N2\/H2 forming gas or short-circuited for Al\/Si electrodes, its sensitivity decreases drastically and almost vanishes. Further I-V and FT-IR results show that the two back-to-back Schottky diodes on the device play a key role in its sensing performance.<\/jats:p>","DOI":"10.3390\/s17081929","type":"journal-article","created":{"date-parts":[[2017,8,22]],"date-time":"2017-08-22T11:08:25Z","timestamp":1503400105000},"page":"1929","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Fast Room Temperature NH3 Sensor Based on an Al\/p-Si\/Al Structure with Schottky Electrodes"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0618-2517","authenticated-orcid":false,"given":"Suwan","family":"Zhu","sequence":"first","affiliation":[{"name":"Collaborative Innovation Center of Advanced Microstructures, State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaolong","family":"Liu","sequence":"additional","affiliation":[{"name":"Shanghai Ultra-Precision Optical Manufacturing Engineering Center and Department of Optical Science and Engineering, Fudan University, Shanghai 200433, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Zhuang","sequence":"additional","affiliation":[{"name":"Shanghai Ultra-Precision Optical Manufacturing Engineering Center and Department of Optical Science and Engineering, Fudan University, Shanghai 200433, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Li","family":"Zhao","sequence":"additional","affiliation":[{"name":"Collaborative Innovation Center of Advanced Microstructures, State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,8,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"666","DOI":"10.1016\/j.snb.2004.11.054","article-title":"Ammonia sensors and their applications\u2014A review","volume":"107","author":"Timmer","year":"2005","journal-title":"Sens. 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