{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T15:19:34Z","timestamp":1775229574780,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,10]],"date-time":"2018-10-10T00:00:00Z","timestamp":1539129600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61701044"],"award-info":[{"award-number":["61701044"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100017596","name":"Natural Science Basic Research Plan in Shaanxi Province","doi-asserted-by":"publisher","award":["Nos. 2018JQ6056 and 2018XNCG-G-01"],"award-info":[{"award-number":["Nos. 2018JQ6056 and 2018XNCG-G-01"]}],"id":[{"id":"10.13039\/501100017596","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Special Fund for Basic Scientific Research of Central Colleges","award":["No. 300103187051 and 300104283215"],"award-info":[{"award-number":["No. 300103187051 and 300104283215"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The ZnO waveguide layer for the Love wave humidity sensor was fabricated by radio frequency (RF) magnetron sputtering technique using ZnO as the target material. To investigate the effect of RF magnetron sputtering temperature on the ZnO waveguide layer and Love wave device, a series of Love wave devices with ZnO waveguide layer were fabricated at different sputtering temperatures. The crystal orientation and microstructure of ZnO waveguide was characterized and analyzed, and the response characteristics of the Love wave device were analyzed by network analyzer. Furthermore, a humidity measurement system is designed, and the performance of the Love wave humidity sensor was measured and analyzed. The research results illustrate that the performance of the ZnO waveguide layer is improved when the sputtering temperature changes from 25 \u00b0C to 150 \u00b0C. However, when the sputtering temperature increases from 150 \u00b0C to 200 \u00b0C, the performance of the ZnO waveguide layer is degraded. Compared with the other sputtering temperatures, the ZnO waveguide layer fabricated at 150 \u00b0C has the best c-axis orientation and the largest average grain size (53.36 nm). The Love wave device has the lowest insertion loss at 150 \u00b0C. In addition, when the temperature of the measurement chamber is 25 \u00b0C and the relative humidity is in the range of 10% to 80%, the fabricated Love wave humidity sensor with ZnO waveguide layer has good reproducibility and long-term stability. Moreover, the Love wave humidity sensor has high sensitivity of 6.43 kHz\/RH and the largest hysteresis error of the sensor is 6%.<\/jats:p>","DOI":"10.3390\/s18103384","type":"journal-article","created":{"date-parts":[[2018,10,10]],"date-time":"2018-10-10T11:53:13Z","timestamp":1539172393000},"page":"3384","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Study on Fabrication of ZnO Waveguide Layer for Love Wave Humidity Sensor Based on Magnetron Sputtering"],"prefix":"10.3390","volume":"18","author":[{"given":"Changbao","family":"Wen","sequence":"first","affiliation":[{"name":"Institute of Micro-Nanoelectronics, School of Electronics and Control Engineering, Chang\u2019an University, Xi\u2019an 710064, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Taotao","family":"Niu","sequence":"additional","affiliation":[{"name":"Institute of Micro-Nanoelectronics, School of Electronics and Control Engineering, Chang\u2019an University, Xi\u2019an 710064, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yue","family":"Ma","sequence":"additional","affiliation":[{"name":"Institute of Micro-Nanoelectronics, School of Electronics and Control Engineering, Chang\u2019an University, Xi\u2019an 710064, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nan","family":"Gao","sequence":"additional","affiliation":[{"name":"Institute of Micro-Nanoelectronics, School of Electronics and Control Engineering, Chang\u2019an University, Xi\u2019an 710064, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Feng","family":"Ru","sequence":"additional","affiliation":[{"name":"Institute of Micro-Nanoelectronics, School of Electronics and Control Engineering, Chang\u2019an University, Xi\u2019an 710064, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"181905","DOI":"10.1063\/1.4875981","article-title":"Evidence of a Love wave bandgap in a quartz substrate coated with a phononic thin layer","volume":"104","author":"Liu","year":"2014","journal-title":"Appl. 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