 Abstract femtosecond laser ablation has been demonstrated to be a versatile tool for producing micro-slash nanoscale, features with high precision and accuracy. However, when using high laser fluences, unwanted effects such as redeposited debris, recast layers, and heat-affected zones may occur. To overcome these limitations, a thin frost layer was used to form a condensed water vapor from the air onto the exposed surface, whose temperature is below the freezing point. This frost layer helps to boost ablation efficiency, suppresses the recast layer, and reduces the heat-affected zone, while the remaining frost layer prevents abrasion debris from sticking to the target surface. The frost-assisted strategy allows for high-quality surface micro-slash nanostructures to be achieved at high laser fluences, and the mechanism behind the formation of high spatial frequency, HSF, laser-induced periodic surface structures, Lipses, on silicon is discussed. This article was authored by Wen Haigao, Kai Zhang, Yang Liao, and others. We are article.tv, links in the description below.