Acquisition Proposal: Laboratory for Large Scale Integration of Nanostructures

California Institute Of Technology, Pasadena CA

Investigators

Abstract

0116776 Roukes Major advances have recently been made at California Institute of Technology (Caltech) in developing and employing what are, largely, individual nanometer-scale structures for applications ranging from fundamental science to technological applications. Within the research groups of the co--P1's, Professor Scherer and Professor Roukes, who have worked together on nanofabrication for the past fifteen years, electron beam lithography techniques have been developed and used for the construction of a wide range of functional nanometer-scale devices. Lateral dimensions below 10 nm are routinely obtained, and students in these groups have developed both expertise in the requisite electron-beam-control code and an in-depth understanding of the specialized resist processing and pattern transfer techniques enabling ultrahigh resolution. The time is now ripe to exploit these advances by creating nanosystems - i.e. advanced structures that comprise coherently coupled arrays of the individual nanoscale elements the authors are perfecting. This equipment acquisition proposal, if funded, would enable such research. Nanodevice arrays are emerging as a priority in nanoscale science and technology. As detailed in this proposal (and its accompanying letters of support), nanoscale arrays will find immediate applications within the proposers' research programs. These currently involve 13 Caltech professors, in disciplines spanning fundamental physics, chemistry, biology, and engineering and materials science. Among the specific topics currently being pursued are: quantum optics, quantum computation, nanophotonics, spin electronics, nanomechanics, neurophysiology, biotechnology, electrochemistry and molecular electronics. These applications require fabrication of structures spanning a hierarchy of size scales -from the smallest dimensions accessible via state-of-the-art nanofabrication techniques, to the millimeter to centimeter domain of integrated, chip-based systems. Fabrication of these complex nanoscale arrays requires multiple, successively-aligned steps of large-field electron beam lithography over the wafer scale. A second important research thrust would be enabled by the proposed instrumentation. This focuses upon future technological applications requiring nanometer-scale features produced lithographically en masse. This scale is far below the dimensions currently accessible via deep ultraviolet lithography, the current industry standard for state-of-the-art commercial production lines. To address this technological need, much recent effort world-wide has focused upon development of new, high-resolution, high-throughput lithographic methods. Projection x-ray lithography, shaped electron beam lithography, and mechanical transfer methods (embossing, molding, or stamping) all have evolved as principle contenders for the definition of sub-I 100nm structures over large areas. All of these techniques, however, have in common the need for wafer-scale high-resolution masks. These are normally generated by vector-scanned electron beam lithography. There are currently no alternative lithographic tools which offer comparable flexibility, resolution and placement accuracy for this purpose as state-of-the-au commercial electron beam writers. Student access to such an instrument would greatly enhance research and training in the proposers' university setting. An entirely new level of instrumentation is required to successfully initiate these proposed endeavors. Specifically, the capability of writing large (wafer scale) fields of features at the sub-5Onm scale is absolutely crucial. This can only be done with a state-of-the-art electron beam writer; however the acquisition of such an instrument is significantly beyond the scope of most funding programs. Here the PIs propose to purchase an electron-beam lithography system for this laboratory. The cost for this instrument will be shared by Caltech ($l.5M), the NSF ($1.OM), and DARPA/DURINT ($l.OM). The laboratory established with these funds will constitute an interactive, "expert" facility within the larger efforts of the PI's. This select, focused group of researchers will include undergraduate and graduate students, staff and faculty members. This group will be collectively dedicated to establishing routes to next-generation structures involving large arrays of nanoscale elements.