The shared facilities of the NSEC serve NSEC related researchers, other internal users at UW, and external users from academia and industry. A central feature of these facilities is the availability and use of synchrotron light for nanotechnology applications. The core capabilities relate to patterning large areas at the scale of ten nanometers and above, combined with the capabilities of measuring, characterizing, transferring, and replicating the structures so produced. Surface-sensitive characterization techniques based on synchrotron radiation compliment the advanced lithographic facilities. As the dimensions of material systems shrink to the nanoscale, surface and interfacial phenomena play increasingly dominant roles in determining material properties. The key instrumentation that is being developed in keeping with these objectives includes: 1) a new insertion device (undulator) at the Synchrotron Radiation Center (SRC) and associated beamlines for a cluster of extreme ultra violet (EUV) exposure stations capable of patterning dense features at a resolution of 18 nm and less, and 2) a near-edge x-ray absorption fine structure (NEXAFS) end station for use with existing beamlines/monochromators at the SRC for the exquisite characterization of the chemical composition, bonding environment, and molecular and atomic-level structure of surfaces. The shared experimental facilities of the proposed NSEC will be collaborative with and leverage existing state-of-the-art instrumentation, human resources, and user networks of three organizations of national and international reputation at UW: the SRC, the NSF MRSEC, and the Center for NanoTechnology (CNTech). Supporting infrastructure will also be provided by the Wisconsin Center for Applied Microelectronics (WCAM) and the UW Materials Science Center (MSC). We have also built new research and user network partnerships with other universities (Cornell), national laboratories (Argonne National Laboratory, Lawrence Berkeley National Laboratory), international laboratories (Paul Scherrer Institute - Switzerland, University of Melbourne - Australia) and industry (Intel, Sematech, JSAL). The shared facilities are anticipated to serve as a starting point for start -up companies, and serve existing companies in nanotechnology (nPoint; nanotube AFM probe tips) and in the biological area (NimbleGen; gene synthesis, Platypus Technologies; biosensors).

We will utilize the new undulator as a source to offer one of the few EUV exposure facilities in the U.S. (EUV lithography is currently the leading candidate to replace optical lithography as critical patterning dimensions reach 50 nm and below.) Recently a robust interferometric exposure configuration has been developed in collaboration with the Paul Scherrer Institute. The tool offers reproducible and unprecedented patterning of dense features with dimensions as small as 18 nm over areas of approximately 50 x 400 μm2. A schematic of the EUV interferometer using a transmission-grating mask is shown in Figure 1 along with patterns that have been printed in photoresist using two and four diffraction gratings. The NSEC procures and maintains EUV masks such that the full range of nanoscale features can be patterned with EUV interferometric lithography.

Patterning capabilities beyond the EUV tool that will be part of the NSEC shared facilities will be leveraged by internal and external collaborative instrumentation. The NSEC will partially support additional exposure stations operated by CNTech that provide the most advanced x-ray lithography facilities in the U.S., including two steppers capable of processing up to six-inch wafers with sub-70nm overlay, and extremely high resolution. Binary masks allow patterning of structures down to dimensions of 35 nm, and the development of x-ray phase mask technology permits patterning of structures down to dimensions of 20 nm. The NSEC procures and maintains x-ray masks with input from current and future internal and external users to meet the research community needs. The NSEC also partially supports an operating 50 KeV electron-beam writing system capable of writing masks and small areas containing prototypical structures or devices with dimensions down to 40 nm.

The advanced lithographic patterning tools are supported on-site by process clean rooms and a full array of sample preparation, metrology, surface characterization, and pattern transfer tools. For metrology, the NSEC shared facilities in collaboration with CNTech offers scanning electron microscopes (2 nm resolution) with elemental detection systems and multiple types of scanning probe microscopes, some equipped with high-resolution nanotube tips. Collaborative pattern transfer equipment (CNTech, WCAM, MRSEC) includes recently purchased inductively coupled plasma etchers for dielectrics, metals, and semiconductors, a high aspect ratio plasma etcher for silicon, and a new nanoimprint lithographic tool for embossing and molding nanofabricated structures from rigid masters.

The SRC synchrotron Aladdin, operating at 800-1000 MeV electron energies, is ideally suited for exploring surface and interfacial phenomena of materials, and for providing information that is not possible to obtain with more commonly assessable tools such as electron microscopes or scanning probes. In addition to the proposed NEXAFS end station, the SRC offers beamlines and instrumentation for many surface characterization techniques using IR, VUV and soft X-ray synchrotron radiation. Also existing at SRC is a PEEM program (photoemission electron microscopy) with the capability of achieving materials analysis at sub-10 nm resolutions.

Synchrotron Radiation Center
http://www.src.wisc.edu

NSF-UW MRSEC
http://www.mrsec.wisc.edu/Facilities.php

Center for Nanotechnology (CNTech)
http://www.nanotech.wisc.edu/facilities/facilities.html

Wisconsin Center for Applied Microelectronics (WCAM)
http://www.engr.wisc.edu/centers/wcam/

UW Materials Science Center
http://msc.engr.wisc.edu

Paul Scherrer Institute
http://www.psi.ch/forschung/benutzerlabor_e.shtml

University of Melbourne
http://www.unimelb.edu.au