Incubation effect during laser micromachining of GaN films with femtosecond pulses

Author(s)

Almeida, G. F. B. ; Nolasco, L. K. ; Barbosa, G. R. ; Schneider, A. ; Jaros, A. ; Clavero, I. Manglano ; Margenfeld, C. ; Waag, A. ; Voss, T. ; Mendonca, C. R.

• Document type: Journal article
• Source: JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS; v. 30, n. 18, p. 6-pg., 2019-09-01.

Abstract

We studied the evolution of the incubation effect during fs-laser micromachining of gallium nitride films with the number of laser pulses applied per sample surface area. The damage threshold fluence was measured using the zero-damage method and reduced from (0.61 +/- 0.01) J/cm(2) to (0.05 +/- 0.03) J/cm(2) when increasing the number of applied laser pulses from single-shot excitation to 10(5) pulses per spot, respectively. By applying the exponential defect accumulation model to the experimental incubation data, we determined a small value for the incubation parameter of (0.011 +/- 0.001), indicating that gallium nitride has slow incubation dynamics. This information is important to achieve the desired control and high efficiency of fs-laser processing of gallium-nitride-based samples. (AU)

• FAPESP's process: 18/11283-7 - Nonlinear photonics: spectroscopy and advanced processing of materials
• Grantee: Cleber Renato Mendonça
• Support Opportunities: Research Projects - Thematic Grants