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Thermodynamical Analysis of the Formation of α-Si Ring Structures on Silicon Surface.

ABSTRACT: Superficial modifications on silicon wafers produced by single-shot focused femtosecond laser irradiation having a 1030 nm wavelength and 300 fs pulse duration were experimentally and theoretically analyzed. The laser fluence window when the amorphous silicon phase develops, resulting in a ring-like modification shape, was experimentally estimated to be between 0.26 J/cm2 and 0.40 J/cm2 and was independent of the silicon dopant type and laser focusing conditions; however, the window was narrower when compared to results reported for shorter pulse durations. In addition, we present a simplified numerical model that can explain and predict the formation of these patterns based on the caloric coefficients of silicon and the energy distribution of the deposited material.

SUBMITTER: Jarutis V

PROVIDER: S-EPMC10058774 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Thermodynamical Analysis of the Formation of α-Si Ring Structures on Silicon Surface.

Jarutis Vygandas V Paipulas Domas D Jukna Vytautas V

Materials (Basel, Switzerland) 20230309 6

Superficial modifications on silicon wafers produced by single-shot focused femtosecond laser irradiation having a 1030 nm wavelength and 300 fs pulse duration were experimentally and theoretically analyzed. The laser fluence window when the amorphous silicon phase develops, resulting in a ring-like modification shape, was experimentally estimated to be between 0.26 J/cm2 and 0.40 J/cm2 and was independent of the silicon dopant type and laser focusing conditions; however, the window was narrower ...[more]

PMID: 36984084

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