Multistep profiles by mix and match of nanoimprint and UV lithography

Abstract

Driven by the steadily increasing scale of integration in microelectronics much effort has been made in recent years to establish the technique of nanoimprint lithography (NIL) as a promising approach to time and cost-effective fabrication of nanometer scale patterns. NIL enables high throughput for mass fabrication in a simple way. Experiments have revealed that nanoimprint of small and periodic patterns in the nm range is much easier obtained than for μm scale patterns due to polymer transport phenomena. Thus a combination of NIL with optical lithography is considered to be advantageous for the definition of small patterns adjacent to large patterns. The multifunctionality of the material within one layer offers new routes in device design, in particular as multistep profiles are obtainable. In this contribution a combination of NIL and UV lithography is reported using polymers which are both imprintable and photosensitive. Based on an epoxy type negative tone chemically amplified resist system patterns were easily obtained using both techniques. In the first step a pattern relief was produced through imprinting. In the second step this relief was UV exposed in a contact printer and then developed. In this way three-step profiles could be generated within one single polymer layer.