Antireflection Micro Patterning using EB-Lithography

This paper describes the fabrication of near infra-red (NIR) antireflective micro structures on a phosphorus doped Si-wafer by direct write EB- lithography followed by RIE-etching. The Fourier transform infra-red (FTIR) measurement done from the structured surface clearly shows a reflection dip at 1.42 mum and 2.5 mum respectively. It is also found that a change in pattern size, shape and its periodicity results a shift in reflection dip accordingly. This dip in reflection spectra is caused by the surface plasmon excitation due to interaction between the incoming photon and surface plasmon resonance. Its application in the frequency selective surfaces (FSS) such as antireflection surface for effective solar radiation absorption can be realized.