A cost-effective method to fabricate spectral-response anti-reflective films by using silicon nano pillar

摘要

Effective harvesting light is a key factor for photoelectrical device to enhance quantum efficiency and responsitivity. Periodic nano structure has been proved and fabricated to harvest more light based on complex lithography and low efficiency e-beam lithography.Thereby, a cost-effective method of using PS sphere as hard mask was suggested to prepare sub-micro nano pillar on silicon surface as anti-reflective films.Field distribution of nano silicon pillar were simulated in FDTD software and simulation results showed that anti-reflective could be modified by changing the silicon diameter and period. The simulation results show that the center wavelength of the high-reflection film moves with the change of the nano pillar period, and the reflection intensity changes with the diameter and length of the nano pillar. Silicon nano pillar with 180nm diameter and 520nm period was determined theoretically and experimentally to be as anti-reflective films covering wavelength from 601nm to 640nm with average reflectance of less than 5%.