Low-oxygen micro/nanostructured grooves in 4 H-SiC by femtosecond-laser grooving and finishing

Silicon carbide (SiC) is a wide-bandgap semiconductor valued for durability and high performance, enabling advanced applications. This study investigates femtosecond-laser grooving of 4 H-SiC to assess the effects of incident face and crystallographic direction on groove morphology, and demonstrates a finishing step using the same laser source to reduce oxides on in-groove nanostructures. V-shaped grooves with in-groove nanostructures were obtained. A subsequent secondary finishing step, implemented with the same laser source, reduced the oxygen content of the nanostructures, yielding micro/nanostructured grooves with reduced oxygen content. These results show that, under the tested conditions, femtosecond-laser grooving produced crack-free grooves, and that the finishing step reduced the oxygen content of in-groove nanostructures.