The Semiconductor Lithographic Process

And the atoms that compose this radiance do not travel as isolated individuals but linked and massed together. 

The object of semiconductor lithography is to transfer patterns of ICs drawn on the mask or reticle to the semiconductor wafer substrate. The transfer is carried out by projecting the image of the reticle with the aid of appropriate optical elements of an exposure tool onto a radiation-sensitive resist material coated on the semiconductor wafer, typically made of silicon, and stepping the imaging field across the entire wafer to complete a layer. The shape of the IC pattern transferred to the wafer substrate is dependent entirely on the wafer layer being patterned. Examples of patterns include gates, isolation trenches, contacts, metal interconnects, and vias to interconnect metal layers. An advanced CMOS (complementary 

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Figure 11.1 Steps of the semiconductor lithographic process. The adhesion promotion step is often skipped when a BARC is applied to the wafer substrate before the resist application step.

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