Laser induced damage characteristics of optical thin film with ion assisted planarization and annealing

ORAL

Abstract

Ion beam sputtering growth of amorphous oxides coupled with processing using Ar ion assist is termed \textit{planarization}. This process was introduced by our team reducing defect cross-section on pre-patterned substrates by up to 90{\%} and increasing laser damage performance by 10x The effects of SiO$_{\mathrm{2}}$ planarization processing on the laser damage resistance of single, bilayers, and multilayer coatings of HfO$_{\mathrm{2}}$ and SiO$_{\mathrm{2}}$ is investigated at pulse durations of 9ps and 220ps. Planarized samples experience a large increase in absorption loss at 1\textmu m wavelength, which is reduced after in-air annealing suggesting presence of oxygen point defects. It is shown the laser damage threshold reduces with planarized SiO$_{\mathrm{2}}$ layers directly implemented compared to control samples at both pulse durations. In-air annealing instead shows a recovery of the laser damage threshold.

*Lawrence Livermore National Laboratory Subcontract No. B623169; and U.S. Department of Energy Accelerator Stewardship program under award DE-SC0016136.

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Authors

  • Hanchen Wang

    • Department of Physics, Colorado State University
    • Physics Department, Colorado State University, Fort Collins, Co 80525
    • Colorado State Univ

  • Travis Day

    • Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Co 80525

  • Elizbieta Jankowska

    • Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Co 80525

  • Breandan Reagan

    • Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Co 80525

  • Jorge Rocca

    • Physics Department, Colorado State University, Fort Collins, Co 80525

  • Christopher Stolz

    • Lawrence Livermore National Lab. (United States)

  • Paul Mirkarimi

    • Lawrence Livermore National Lab. (United States)

  • James Folta

    • Lawrence Livermore National Lab. (United States)

  • John Roehling

    • Lawrence Livermore National Lab. (United States)

  • Carmen Menoni

    • Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Co 80525