The history of imprint technology as lithography method for pattern replication can be traced back to 1970’s but the most significant progress has been made by the research group of S. Chou in the 1990’s. Since then, it has become a popular technique with a rapidly growing interest from both research and industrial sides and a variety of new approaches have been proposed along the mainstream scientific advances. Nanoimprint lithography (NIL) is a novel method for the fabrication of micro/nanometer scale patterns with low cost, high throughput and high resolution. Unlike traditional optical lithographic approaches, which create pattern through the use of photons or electrons to modify the chemical and physical properties of the resist, NIL relies on direct mechanical deformation of the resist and can therefore achieve resolutions beyond the limitations set by light diffraction or beam scattering that are encountered in conventional lithographic techniques. The ability to fabricate structures from the micro- to the nanoscale with high precision in a wide variety of materials is of crucial importance to the advancement of micro- and nanotechnology and the biotech- sciences as a whole and will be discussed in this paper. Nanoimprinting can not only create resist patterns, as in lithography, but can also imprint functional device structures in various polymers, which can lead to a wide range of applications in electronics, photonics, data storage, and biotechnology.
The NILaustria research project cluster consists of 8 individual research projects and aims to improve nanoimprint
lithography in an application driven approach. The cluster is presented as well as highlights from the projects, e.g. the
replication of 12.5nm half pitch features using working stamp copies, topics from organic electronics, metamaterials and
SiGe technology. An outlook on the new activities is given.
Nanoimprint technology already demonstrated high resolution capability using hard master stamps in the mid 90's.
Considering this as a well known technology, there are still restrictions making nanoimprint lithography (NIL) a
competitive "next generation lithography" technique. This paper will address limitations in regard to large area master
stamp manufacturing, resolution and lifetime using soft UV-NIL imprint lithography on stamps fabricated by massively
parallel ion beam lithography provided by the CHARPAN tool. It provides detailed information of sub- 15 nm (dots,
grids and lines) replication processes at master fabrication, working stamp replication and imprinting.
Nanoimprint Lithography (NIL) is a high throughput replication technology for structures ranging from micrometer
down to few nanometers. NIL can be divided into UV-Nanoimprint (UV-NIL) and Hot embossing (HE). The main
difference between these two techniques are the material types of both template and resist, i.e transparent templates
and photosensitive resists for UV-NIL and non transparent templates and thermoplastic resists for HE. Hot
embossing is a low-cost, high throughput fabrication technique of disposable, polymer based devices needed for
emerging point-of care diagnostic or bio-sensing applications. This paper describes the technology for imprinting of
polymer substrates as well as spin-on polymers by using soft working stamp materials on a fully automated hot
embossing system, the EVG<sup>R</sup>750, built to use this rapid replication processes. Soft working stamps demonstrate the possibility to replicate both, high-aspect ratio features in thermoplastic materials as needed for microfluidic lab-on-chip applications as well as high resolution features down to 50 nm in polymers that can be used as templates for pattern transfer in the fabrication of plasmonic substrates for biosensing applications.
There are several applications either currently in production or in late stage R&D, for
UV-based Nanoimprint Lithography (UV-NIL) and Hot Embossing (HE) that require a
full-field imprint technology in order to make these processes either feasible or costeffective.
These applications cover a wide range of features sizes from the millimeter
range down to sub-100 nm. Because of the total thickness variation (TTV) associated
with the imprinted substrates, full-field imprinting requires fabrication of a "soft" or
"working" stamp from a "hard" stamp usually made from materials such as nickel, quartz
or silicon. Several materials and processes have previously been identified that allow for
full-field imprinting, however, these materials all have drawbacks associated with them
that hinder their movement into High Volume Manufacturing (HVM) environments. EV
Group Inc (EVG) has, in cooperation with our NILCOM<sup>TM</sup> partners, identified a novel set
of polymeric materials and stamp fabrication processes that allow for full-field imprinting
solutions suitable for these HVM environments. These materials have proven effective
for imprinting at both millimeter feature sizes all the way down to 50 nm - full field.
These materials, and the processes associated with their fabrication into working/soft
stamps, should allow for a superior cost-of-ownership benefit and facilitate the movement
of imprint lithography into industrial applications.