Silicon grating foil used to analyze the image transfer function in XUV radiography system
The image transfer function is used to judge the precision of XUV radiography system and silicon grating foils are prepared to measure the image transfer function. Using photoetching and ion beam etching processes, the silicon grating foils with check and stripe pattern were prepared on thin silicon foil. The thickness of thin silicon foil was 3 to 4 μm and the pattern's etching depth was about 1 μm. The size of check pattern was 25 μm×25 μm and the width of stripe pattern was 5 μm. The parameters of photoetching and ion beam etching processes were studied to control the precision of patterns. And silicon grating foils were used to measure the image transfer function by XUV radiography system on "Shenguang Ⅱ" high power laser facility in 2000.