Laser Annealing System
Laser annealing is the modification of the surface layer such as an amorphous Si film formed on a wafer or glass substrate to poly-Si by laser. Annealing system using solid-state laser has little downtime and supports system from 4 inch wafer to G6 substrate.
By using UV-SLA, laser annealing with a flat top profile with a large DoF like the profile on the left can be performed. By using this top flat profile, high-speed scanning of 20 mm / s and periodic pattern structure (LIPPS) of poly-Si thin film can be obtained. Since the speed can increase the production tact time, the periodic pattern structure contributes to the speed improvement of the device. UV-SLA enables high throughput and low cost of ownership (40-50% of ELA).
The photo on the left is a SEM image of a thin film after laser annealing in which amorphous silicon is poly-siliconized with a flat top profile by VOLCANO®100UV SLA, a system that uses a UV solid-state laser. Each cell has an irregular shape, but has a regular grain structure as a whole. This period is almost equal to the wavelength of 343 nm of UV solid state laser.