Research Of Nano-grating Fabrication Based On PDMS

As a very important optical component,grating is widely used in the field of integrated optical circuit, optical communications, optical interconnects, optical information processing, optical measurement,etc.. At present, the application of the grating are concentrated at the nanometer scale.Therefore,the study on nano-grating fabrication has a very important significance.Currently, the method of nano-grating production varies. However, existing nano-gratingprocessing, such as holographic lithography, electron beam lithography, ion beam lithography, X-ray lithography etc., always require expensive equipment, complex and difficult controling, harsh processing conditions,and long cycle.The femtosecond laser direct writing, dual-beam interference method can be also used to produce the grating with a period of a few hundrednanometers.But it is hard to obtain a satisfactory straightness using these methods.At the sametime,they also demand complex optical circuits and precise controling.To solve these problems, this paper presents a novel nanoscale grating processing. First,a micronscale grating is fabricated using conventional photolithographic methods.Then molding it with PDMS and stretching the PDMS membrane along the direction of the grating lines to reduce the period of grating.And transfer the grating pattern from the PDMS membrane to PMMA.Nano-grating can be obtained by repeating the steps for sevaral times.The grating has been tested and performs well.Using this method,nano-grating can be processing with low cost and short cycle.The process is simple and easy to control,particularly suitable for the production of a large area of thegrating structure.