Projection printing positive resists

Figure 3.29. (top) Positive and (bottom) negative images projection printed in a polyijp-formyloxystyrene) resist. Reproduced from reference 103. Copyright 1984 American Chemical Society.)... 

Figure 3.30. SEMs of (top) positive and (bottom) negative J- xm images projection printed in a tertiary butyl ester-onium salt resist. Reproduced with permission from reference 105. Copyright 1986 Electrochemical Society.)...

The photoresists are exposed through a mask by contact or projection printing with the 3650, 4050, and 4350A° mercury lines. Electron beams 5-30KV and x-rays 2-lOA have also been employed. The positive resist reproduces the mask or image in a direct positive replication while a negative resist reproduces an image reversal of the opaque portions of the mask. 

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