Non-chemically amplified positive resists

1 Non-chemically ampliflied positive resists based on functional group polarity switch 

The roots of DNQ-novolac resists stretches all the way back to the ozalid process, mentioned above, which dates to the invention around 1917 of the process for making architectural blueprint papers by Gustav Kogel (1882-1945) and 

The diazoquinone-novolac positive plates were only a moderate commercial success, but interest in the diazoqunone-novolac systems was revived in the 1970s when the resolution requirements of the semiconductor industry outpaced the capabilities of the negative bis-azide resists then in use. It was during this time that the diazoquinone resists established themselves as nonswelling, high-resolution imaging materials in the semiconductor industry. 

Sometime between 1930 and 1940, Oskar Siiss of the Kalle Company invented the DNQ/novolac resist system, spurred on perhaps by the motivation of combining the two functional groups involved in the azocoupling reaction of their blueprint chemistry into one molecule.  

Willson, R.A. Dammel, and A. Reiser, Photoresist materials a historical perspective, Proc. SPIEiQSQ, 38 51 (1997). 

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Non-chemically amplified positive resists based on main chain scission... 

In a positive tone resist, the areas that are exposed to the radiation develop away into solvent faster than unexposed areas, resulting in a positive tone image of the mask. The majority of commercial, positive tone, non-chemically amplified resists used today are variations on... 

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