Promising low-damage fabrication method for the photonic crystals with hexagonal or triangular air holes: selective...

The photonic band diagrams of the photonic crystal slabs (PCSs) with various structural air holes were calculated by plane wave expansion method with super cell method. The calculated results indicate that the PCSs with hexagonal or triangular air holes have enough large photonic band gaps in the guided mode spectrum, hence they are good candidates to be used for the PC devices. The PCs with hexagonal or triangular air holes were fabricated successfully on n-type GaAs (111)B substrate by selective-area metal organic vapor phase epitaxy (SA-MOVPE). Vertical and smooth facets are formed and the uniformities are very good. The same process was also used to fabricate hexagonal air hole arrays with the width of 100 nm successfully. A procedure was proposed and utilized to fabricate the air-bridge PCS with normal hexagonal air holes. The fabricated hexagonal air holes are very uniform and the sidewalls are smooth and vertical. Our experimental results indicate that SA-MOVPE growth is a promising low-damage fabrication method for PC devices and photonic nano-strucutres.