MICROFABRICATION OF HOLOGRAPHIC BLAZED GRATING BY REACTIVE ION BEAM ETCHING.

The SiO//2 holographic blazed grating with good quality and high diffraction efficiency has been developed by reactive ion beam etching and holographic grating mask made by lensless Fourier transform holography recording. The authors investigated the techniques of the photoresist coating, holographic exposure and development so that the mask pattern of the AZ1350 photoresist holographic grating should be made suitable for reactive ion beam etching. Then, the SiO//2 holographic blazed gratings with space frequency of 1000 lines/mm are microfabricated by CF//4 ion beam etching. The etching rate of SiO//2 and AZ1350 photoresist has been determined. The blazed angle of gratings can be controlled by varying the incident angle of the ion beam. The advisable etching technology parameters have been chosen and the experimental results of the SiO//2 holographic blazed grating with 67% diffraction efficiency have been achieved.