Fabrication of Silicon Surface Grating Structures by Maskless Laser Beam Lithography
International Journal for Research in Applied Science and Engineering Technology
I report on the mask-less fabrication of grating structures on silicon surface with pulsed laser beam exposure. The mask-less fabrication of grating structures has been carried out with two-beam holographic exposure of fourth harmonic wavelength (266 nm) of Nd: YAG laser. I have investigated the grating surface by Fourier method to understand the effect of number of laser pulses on patterned surface. The root mean square (RMS) roughness, power spectral density (PSD) and crosssectional analysis
... sectional analysis have been carried out to understand the effect of increasing number of shots. It has been observed that with increasing the number of shots, valley depth of grating pattern increases which leads to many spatial frequency components other than the fundamental frequency of the structure due to increase in extreme amount of interfacial roughness. The influence of number of laser shots on the periodicity of grating structures is reported.