Method for preparing photoresist grating masks

A method was developed for preparing photoresist masks with a specified period and gap between the grooves. An analysis was made of the conditions determining the exposure time, development time, and developer concentration necessary to produce a mask with a given gap width. The proposed method was developed basically for masks with gaps equal to the width of a groove on any substrate. The limits of suitability of the method for preparing masks with a specified groove profile were established. All the experiments were carried out on photoresist films made of FP-RN-7 on glass substrates. Photoresist masks of two types were prepared with periods 0.4, 0.6, and 0.74 $\mu m$; this was done for two film thicknesses. The deviation of the mask parameters from the calculated values did not exceed 20%.