Negative photoresist commercially available

The resists employed for wet etching adhesion experiments were typical commercially available azide initiated/cyclized isoprene type negative photoresists. 

Positive and negative photoresists have their own advantages and disadvantages. General consideration of the photoresists includes its adhesion on the substrate, the minimum feature size permitted, the resistance to chemicals, the cost, and others. Most of the commercially available photoresists provide information about the properties and the suitable developers of the photoresists. 

There are many photoresists available commercially. These can be categorised into positive and negative tone resists. Various formulations of resists have differing properties (viscosity, ultimate achievable resolution, substrate adhesion etc.). Several classes of resist have thus been developed for different electronic applications. For example, high-resolution photolithography for patterning of submicron transistors requires a different resist to that needed for deep silicon etching of micro-electro-mechanical-systems (MEMS) stmctures. 

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