1. Singh Center for Nanotechnology, University of Pennsylvania, 3205 Walnut Street, Philadelphia, Pennsylvania 19104
2. University of Delaware Nanofabrication Facility, 221 Academy Street, Newark, Delaware 19716
3. Materials Research Institute, The Pennsylvania State University, Millennium Science Complex, University Park, Pennsylvania 16802
4. GenISys, GmbH, Eschenstr. 66, D-82024 Taufkirchen, Germany