DIRECT PHOTOETCHING OF SINGLE-CRYSTAL SIC BY VUV-266 NM MULTIWAVELENGTH LASER-ABLATION

Single crystal SiC substrate was successfully photoetched at a remarka bly high etch rate of 35 nm/s by VUV (133, 141, 150, 160, 171 and 184 nm)-266nm multiwavelength laser ablation, combined with a chemical pos t-treatment in a solution of HCl : H2O2 : H2O and HF: H2O. The analysi s of the etched samples by scanning electron microscopy (SEM) and scan ning probe microscopy (SPM) indicates that an array of square holes ha ving well-defined patterned structures and clean substrate surfaces we re obtained. The X-ray photoelectron spectroscopy (XPS) analysis indic ates that the SiC samples etched by VUV-266 nm multiwavelength laser h ave a similar stoichiometry after chemical post-treatment as the virgi n SiC. The mechanism of high-duality ablation using VUV-266 nm multiwa velength laser is discussed in comparison with ablation using 266 nm s ingle wavelength. The chemical post-treatment contributes to removing the residues from the laser photolysis of SiC.