What is "diazonaphthoquinone"

n. (context chemistry English) A diazo derivative of naphthoquinone.

Diazonaphthoquinone (DNQ) is a diazo derivative of naphthoquinone. Upon exposure to light, it undergoes a Wolff rearrangement to form a ketene. This chemical reaction is exploited with a variety of diazonaphthoquinone derivatives in the semiconductor industry.

Diazonaphthoquinone sulfonic acid esters are commonly used as components of photoresist materials for semiconductor manufacturing. In this application DNQs are mixed with Novolac resin, a type of phenolic polymer. The DNQ functions as a dissolution inhibitor. During the masking/patterning process, portions of the photoresist film are exposed to light while others remain unexposed. In the unexposed regions of the resist film, the DNQ acts as a dissolution inhibitor and the resist remains insoluble in the aqueous base developer. In the exposed regions, the DNQ forms a ketene, which, in turn, reacts with ambient water to form a base soluble indene carboxylic acid. The exposed regions of the photoresist film become soluble in aqueous base; thus allowing the formation of a relief image during development.