UV source for solar cell processing and scatterometry

Activity: Talks and presentationsConference presentations

Description

Gas-filled hollow core fibers are promising and unique platform for generation of ultrafast and wavelength-tunable UV light. We present our recent advances from lab experiments focused towards two industrial applications: scatterometry and laser processing of solar cells, requiring vastly different spectral characteristics. Scatterometry necessitates a broadband, flat, and low noise spectrum, which we achieve through pump modulation. By periodically modulating the power of the individual pulses, we create a low noise pseudo-supercontinuum spanning 250 nm to 860 nm with less than 15 dB variation in power spectral density. Processing of solar cells, in particular laser scribing through ablation, requires high fluence (~1 J/cm2) and benefits from short pulses thus limiting thermal effects. However, for thin film solar cells the bandgap variation of each layer giving a transparency to the visible light might result in unwanted absorption in subsurface layers. Operating at wavelengths with high absorption and low transmission of the top layer can potentially alleviate such unwanted effects, but requires a wavelength tunable source to target the individual layers. We present preliminary results of such an approach using our UV source.
Period30 Jan 20241 Feb 2024
Event titlePhotonics West Exhibition: PWE 2024
Event typeExhibition
LocationSan Francisco, CA, United States, CaliforniaShow on map
Degree of RecognitionInternational