{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T03:51:07Z","timestamp":1773373867319,"version":"3.50.1"},"posted":{"date-parts":[[2026]]},"group-title":"SSRN","reference-count":34,"publisher":"Elsevier BV","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Germanium\u2013antimony\u2013telluride (GST) and selenium-doped GST (GSST) alloys are widely investigated as phase-change materials for photonic and memory applications due to their tunable crystallization and optical properties. While encapsulation is commonly employed to mitigate degradation, the chemical and structural instability of uncapped GST and GSST thin films, particularly at high temperatures, remains poorly quantified. In this work, we investigate the thermal stability, crystallization behavior, and optical response of thermal evaporated GST and GSST films with different selenium contents annealed at 200 \u00b0C and 350 \u00b0C under low-vacuum (LV) and high-vacuum (HV) conditions. Thickness measurements, energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and optical transmittance were used to decouple thermal effects from oxygen-assisted degradation mechanisms. LV annealing promotes significant thickness loss, stoichiometric drift\u2014dominated by tellurium depletion, and disrupted crystallization, especially at 350 \u00b0C. In contrast, HV annealing strongly suppresses chemical instability, preserves film thickness within densification limits, and restores crystallization behavior consistent with intrinsic phase evolution. Although GSST films exhibit higher optical transmittance than GST after crystallization, selenium incorporation does not prevent degradation under oxygen-accessible conditions at high-temperature. These results highlight the critical role of the annealing environment in controlling the stability and performance of uncapped GST-based films at high temperatures.<\/jats:p>","DOI":"10.2139\/ssrn.6402404","type":"posted-content","created":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T17:43:10Z","timestamp":1773337390000},"source":"Crossref","is-referenced-by-count":0,"title":["Impact of different annealing conditions on the physical and optical properties of GST and GSST thin films"],"prefix":"10.2139","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-5697-2688","authenticated-orcid":true,"given":"R.  J.","family":"Machado","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3285-9306","authenticated-orcid":true,"given":"J.  M.","family":"Borlido","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8198-6024","authenticated-orcid":true,"given":"E.  M. F.","family":"Vieira","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2527-5006","authenticated-orcid":true,"given":"J.  A.","family":"Rodrigues","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5991-1069","authenticated-orcid":true,"given":"Jos\u00e9","family":"Correia","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0009-0003-8990-8145","authenticated-orcid":true,"given":"Filipa  Carvalho","family":"Mota","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6318-9021","authenticated-orcid":true,"given":"Diogo  E.","family":"Aguiam","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0009-0002-1701-3396","authenticated-orcid":true,"given":"B.  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