An optimised fused silica stamp etch with 30 nm features to 200 nm depth. (SEM image: Oxford Instruments)

September 20, 2007 — Oxford Instruments and NIL Technology have collaborated to develop etch processes targeted specifically at nanoimprint lithography (NIL). NIL, a versatile, cost effective, and flexible high-throughput method for fabrication of structures as small as 10 nm, has a wide range of application within, for example, data storage, optics, and biosensors.

The collaboration combines Oxford Instruments’ process development expertise in plasma etching with NIL Technology’s experience in developing and supplying templates, stamps, and processes for NIL. Together the companies have developed processes for the etching of nanoimprinting stamps in fused silica, de-scumming of the imprinted polymer with negligible critical dimension (CD) loss, and etch of the final structure.

The etch developments were carried out using Oxford Instruments’ Plasmalab System100 inductively-coupled plasma (ICP) tool. The company says that ICP etch shows superior capabilities for etching of high performance NIL stamps with well-controlled profiles. The stable low pressure de-scum process possible with ICP effectively removes residual polymer after imprinting with minimal loss of CD; ICP is also well suited for transferring the imprinted pattern into fused silica and silicon.

“We saw an opportunity for NIL Technology and Oxford Instruments to work together to develop processes which are optimised as an overall end-to-end process rather than in individual steps,” says Brian Bilenberg, Chief Technical Officer of NIL Technology. “As we continue further work, we expect to improve the whole process of etching nanostructures created by nanoimprint lithography yet more.”