Nanoimprint and micro-contact printing tri-layer processes

Replication of patterns at a nanometer scale is a challenge for both advanced optical lithography and post-optical techniques. Considerable industrial effort has been devoted to the so-called leading-edge optical methods and the next generation lithography techniques. In parallel, a number of low-cost techniques such as nanoimprint and micro-contact printing are being investigated. In these methods, pattern replication is performed in non-conventional ways so that diffraction and scattering problems are no longer relevant. However, several other critical issues have to be studied. This paper describes two tri-layer pattern-transfer techniques, which can be used to improve the process latitude and the process compatibility. Pattern replication and lift-off transfer with feature sizes down to 30 nm and 150 nm have been achieved respectively by nanoimprint and micro-contact printing. As application examples, high-density magnetic dot structures are obtained and studied by measuring magneto-optical Kerr hysteresis loops.