Ultraviolet antireflective porous nanoscale periodic hole array of 4H-SiC by Photon-Enhanced Metal-assisted chemical etching

Benefitting from the outstanding stability and suitable bandgap energy, silicon carbide (SiC) shows promising applications especially for ultraviolet light detection in harsh environments. Traditionally, 4H-SiC surface antireflection textures which boost light harvesting have been realized by plasma dry etching due to its chemical inertness, nevertheless causing surface damage which is detrimental to device performance. This paper presents 4H-SiC porous nanoscale periodic hole array with outstanding ultraviolet antireflection capability by highly efficient plasma-free photon-enhanced metal-assisted chemical etching. Its formation process is carefully monitored with etching mechanism explained by carrier generation and mass transport. Effect of pattern dimension on etching is also investigated, which is closely related with catalyst coverage. The 4H-SiC porous nanoscale periodic hole array by photon-enhanced metal-assisted chemical etching sheds light on novel applications in ultraviolet light harvesting and detection.