The Design And Fabrication Of Phase Mask

The fabrication and characteristics of phase mask are investigated theoretically and experimentally in the paper. The main contents are as follows: The significance of the research of the phase mask and the progress abroad and home of the research on phase mask are presented. The meanings of ion-beam etching for the fabrication of phase mask are discussed, and the progress of the research on ion-beam etching are introduced.According to the different require of the phase mask, the holographic recording method for the design of linearly chirped phase mask is studied in this paper. The fringe formed by the interference of two spherical waves, whose density varies linearly with space, is used to record the chirped phase mask. The two design schemes proposed in this paper are analyzed and compared, and the experimental results are given. Some linearly chirped phase mask are fabricated.The diffraction efficiency of phase mask is discussed by using rigorous coupled-wave theory. The results are useful for fabrication of phase mask. And the diffraction efficiency of linearly chirped phase mask is discussed, it presents require of ion-beam etching. The theory of ion-beam etching and ion sources are reviewed. The classification of ion-beam etching are introduced. According to the mechanism that ion sputtering leads to faceting, trenching, reflection and redeposition, some relative solutions are put forward. The feasibility that Kaufman ion source is applied in reactive ion beam etching is discussed. Etching characteristics of materials, including PR ,Cr ,quartz, are investigated. The etch rate and mechanisms of such materials are measured and analyzed as a function of ion energy, ion beam density and ion incidence angle in pure Ar and CHF3,respectively.The etch rate has shown a square root dependence on variation versus. It offers useful...