{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T00:29:55Z","timestamp":1772756995773,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,8,3]],"date-time":"2025-08-03T00:00:00Z","timestamp":1754179200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Astrometric Reference Frame project","award":["NO. JZZX-01"],"award-info":[{"award-number":["NO. JZZX-01"]}]},{"name":"Astrometric Reference Frame project","award":["NO. CX-500"],"award-info":[{"award-number":["NO. CX-500"]}]},{"name":"Astrometric Reference Frame project","award":["2020244"],"award-info":[{"award-number":["2020244"]}]},{"DOI":"10.13039\/501100015491","name":"Innovation Special Project of SITP","doi-asserted-by":"publisher","award":["NO. JZZX-01"],"award-info":[{"award-number":["NO. 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JZZX-01"]}],"id":[{"id":"10.13039\/501100004739","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004739","name":"Youth Innovation Promotion Association, CAS","doi-asserted-by":"publisher","award":["NO. CX-500"],"award-info":[{"award-number":["NO. CX-500"]}],"id":[{"id":"10.13039\/501100004739","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004739","name":"Youth Innovation Promotion Association, CAS","doi-asserted-by":"publisher","award":["2020244"],"award-info":[{"award-number":["2020244"]}],"id":[{"id":"10.13039\/501100004739","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Potassium bromide (KBr) thin films were deposited by resistive thermal evaporation at substrate temperatures ranging from 50 \u00b0C to 250 \u00b0C to systematically elucidate the temperature-dependent evolution of their physical properties. Structural, morphological, and optical characteristics were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and Fourier transform infrared spectroscopy (FTIR). The results reveal a complex, non-monotonic response to temperature rather than a simple linear trend. As the substrate temperature increases, growth evolves from a mixed polycrystalline texture to a pronounced (200) preferred orientation. Morphological analysis shows that the film surface is smoothest at 150 \u00b0C, while the microstructure becomes densest at 200 \u00b0C. These structural variations directly modulate the optical constants: the refractive index attains its highest values in the 150\u2013200 \u00b0C window, approaching that of bulk KBr. Cryogenic temperature (6 K) FTIR measurements further demonstrate that suppression of multi-phonon absorption markedly enhances the infrared transmittance of the films. Taken together, the data indicate that 150\u2013200 \u00b0C constitutes an optimal process window for fabricating KBr films that combine superior crystallinity, low defect density, and high packing density. This study elucidates the temperature-driven structure\u2013property coupling and offers valuable guidance for optimizing high-performance infrared and cryogenic optical components.<\/jats:p>","DOI":"10.3390\/ma18153644","type":"journal-article","created":{"date-parts":[[2025,8,4]],"date-time":"2025-08-04T15:30:06Z","timestamp":1754321406000},"page":"3644","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Effect of Substrate Temperature on the Structural, Morphological, and Infrared Optical Properties of KBr Thin Films"],"prefix":"10.3390","volume":"18","author":[{"given":"Teng","family":"Xu","sequence":"first","affiliation":[{"name":"Shanghai Key Laboratory of Optical Coatings and Spectral Modulation, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"School of Physical Science and Technology, ShanghaiTech University, Shanghai 200031, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6973-6604","authenticated-orcid":false,"given":"Qingyuan","family":"Cai","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Optical Coatings and Spectral Modulation, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"School of Optoelectronics, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-3904-1061","authenticated-orcid":false,"given":"Weibo","family":"Duan","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Optical Coatings and Spectral Modulation, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"School of Optoelectronics, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kaixuan","family":"Wang","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Optical Coatings and Spectral Modulation, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"School of Optoelectronics, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-7471-6960","authenticated-orcid":false,"given":"Bojie","family":"Jia","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Optical Coatings and Spectral Modulation, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"School of Optoelectronics, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haihan","family":"Luo","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Optical Coatings and Spectral Modulation, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"School of Optoelectronics, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0628-9055","authenticated-orcid":false,"given":"Dingquan","family":"Liu","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Optical Coatings and Spectral Modulation, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"School of Physical Science and Technology, ShanghaiTech University, Shanghai 200031, China"},{"name":"School of Optoelectronics, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2157","DOI":"10.1364\/AO.36.002157","article-title":"Optical and Durability Properties of Infrared Transmitting Thin Films","volume":"36","author":"Kruschwitz","year":"1997","journal-title":"Appl. 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