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半导体生产中的光刻工艺要求使用能确定器件某种特征的高质量的掩模材料。除了要求掩模材料能阻挡光刻操作所必需的光化辐射外(主要是紫外线),对掩模材料的要求可能是完全不同的。对各类掩模的基本要求是薄膜要耐用、耐划、热稳定性好、与玻璃的粘附性好、以及能抵抗有机清洗剂或溶剂的浸蚀,没有针孔等。最通用的材料是在钠钙玻璃或硼硅玻璃板上的700～1000埃厚的铬。铬掩模较早地取代了照相乳剂掩模,因为不透光层较薄、较硬,以及线条清晰。超大规模集成电路(VLSI)微型化的趋势,结合由电子束制造主掩模和投影复印,也已增加了对掩模材料的要求。发展 VLSI 的重点放在低缺陷密度和无针孔的材料上。增加图形的复杂性和使用正性抗蚀剂导致了大量掩模的大范围不透明,因此定位更
Photolithography processes in semiconductor manufacturing require the use of high quality masking materials that can determine certain features of a device. In addition to requiring the mask material to block the actinic radiation necessary for lithographic operations (primarily UV), the requirements for the mask material may be quite different. The basic requirements for all types of masks are durability, scratch resistance, good thermal stability, good adhesion to glass, and resistance to organic cleaning agents or solvents, no pinholes, etc. The most common material is 700-1000 Angstroms thick chrome on soda lime glass or borosilicate glass. Chromium masks earlier replaced photographic emulsion masks because the opaque layer was thinner, harder, and the lines clear. The trend toward miniaturization of very large scale integrated circuits (VLSIs), coupled with the fabrication of master masks and projection copies by electron beams, has also increased the need for masking materials. The focus of VLSI development is on low defect density and pinhole-free materials. Increasing the complexity of the graphics and the use of positive resists have led to the widespread opacity of a large number of masks, so positioning