Fabrication of photonic crystal structures on light emitting diodes by nanoimprintlithography

Abstract

Photonic crystal (PC) structures on green light emitting diodes (LED) were successfullyfabricated using nanoimprint lithography. The stamp, with a two-dimensionalpillar structure, was fabricated using laser interference lithography through adouble exposure technique. To achieve PC structures with a precise dimension,thermal treatment of the photoresist was employed during stamp fabrication; thisproved to be effective for the control of the diameter and shape of the hole. Thetwo-dimensional PC structures, with a period of 295 nm, diameter of 180 nm anddepth of 100 nm, on the green LEDs resulted in nine-fold enhancement of thephotoluminescence intensity compared to the as-deposited samples without PC structures.