In our second White Paper we focus on greyscale lithography. It is applied to manufacture complex 2.5D and freeform microstructures in photoresists. The thus obtained structures serve as master or template for different methods of pattern transfer into materials for final, permanent applications.
In this paper we describe the chemical background and processing fundamentals of typical positive photoresists used for this purpose as well as the characteristics of the ma-P 1200G resist series developed by us specifically for enabling greyscale lithography. Different patterning examples with ma-P 1200G resists are presented as well as a method to transfer such 2.5D resist patterns by UV moulding into hybrid polymers OrmoStamp® and OrmoComp® for permanent applications.
Link to the white paper