{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T08:48:47Z","timestamp":1769071727251,"version":"3.49.0"},"reference-count":31,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T00:00:00Z","timestamp":1633824000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Research Council of Science &amp; Technology","award":["CRC-19-02-ETRI"],"award-info":[{"award-number":["CRC-19-02-ETRI"]}]},{"name":"the National Research Foundation of Korea","award":["2021R1A2C2014098"],"award-info":[{"award-number":["2021R1A2C2014098"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>To realize high-resolution thermal images with high quality, it is essential to improve the noise characteristics of the widely adopted uncooled microbolometers. In this work, we applied the post-metal annealing (PMA) process under the condition of deuterium forming gas, at 10 atm and 300 \u00b0C for 30 min, to reduce the noise level of amorphous-Si microbolometers. Here, the DC and temperature coefficient of resistance (TCR) measurements of the devices as well as 1\/f noise analysis were performed before and after the PMA treatment, while changing the width of the resistance layer of the microbolometers with 35 \u03bcm or 12 \u03bcm pixel. As a result, the microbolometers treated by the PMA process show the decrease in resistance by about 60% and the increase in TCR value up to 48.2% at 10 Hz, as compared to the reference device. Moreover, it is observed that the noise characteristics are improved in inverse proportion to the width of the resistance layer. This improvement is attributed to the cured poly-silicon grain boundary through the hydrogen passivation by heat and deuterium atoms applied during the PMA, which leads to the uniform current path inside the pixel.<\/jats:p>","DOI":"10.3390\/s21206722","type":"journal-article","created":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T21:37:49Z","timestamp":1633901869000},"page":"6722","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Noise Improvement of a-Si Microbolometers by the Post-Metal Annealing Process"],"prefix":"10.3390","volume":"21","author":[{"given":"Jaesub","family":"Oh","sequence":"first","affiliation":[{"name":"Division of Nano Convergence Technology, National NanoFab Center, Daejeon-si 34141, Korea"}]},{"given":"Hyeong-sub","family":"Song","sequence":"additional","affiliation":[{"name":"Foundry Business, Samsung Electronics Co., Suwon-si 18448, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4606-0036","authenticated-orcid":false,"given":"Jongcheol","family":"Park","sequence":"additional","affiliation":[{"name":"Division of Nano Convergence Technology, National NanoFab Center, Daejeon-si 34141, Korea"}]},{"given":"Jong-Kwon","family":"Lee","sequence":"additional","affiliation":[{"name":"Division of Energy and Optical Technology Convergence, Cheongju University, Cheongju-si 28503, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1016\/j.infrared.2010.12.003","article-title":"Recent progress in infrared detector technologies","volume":"54","author":"Rogalski","year":"2011","journal-title":"Infrared Phys. 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