Thermal simulation of KrF excimer laser doping into β-Ga ₂ O ₃ based on TCAD

Abstract We present a thermal simulation study of the KrF excimer laser doping of Sn into β-Ga 2 O 3 (010) from a SnO 2 top layer. Under various conditions, the laser doping experiments and technology computer-aided design (TCAD) simulations were executed, and their results were comparatively analyzed. The transient temperature-field analysis revealed that each laser pulse induced an intense but transient (~ 100 ns) temperature peak confined to a shallow surface region (sub-μm). At a high repetition frequency of 1000 Hz, the incomplete cooling between pulses causes significant heat accumulation at the surface, resulting in enhanced Sn diffusion at 0.3 J/cm 2 , whereas it was negligible at 100 Hz. The diffusion lengths were estimated from the simulated temperature results, and they showed good agreement with the Sn depth profiles. These results demonstrate that TCAD-based thermal simulation is effective for describing the temperature field and the dopant diffusion in excimer laser doping of β-Ga 2 O 3 .