Direct-Write Ion Beam Lithography

Patterning with a focused ion beam (FIB) is an extremely versatile fabrication process that can be used to create microscale and nanoscale designs on the surface of practically any solid sample material. Based on the type of ion-sample interaction utilized, FIB-based manufacturing can be both subtractive and additive, even in the same processing step. Indeed, the capability of easily creating three-dimensional patterns and shaping objects by milling and deposition is probably the most recognized feature of ion beam lithography (IBL) and micromachining. However, there exist several other techniques, such as ion implantation- and ion damage-based patterning and surface functionalization types of processes that have emerged as valuable additions to the nanofabrication toolkit and that are less widely known. While fabrication throughput, in general, is arguably low due to the serial nature of the direct-writing process, speed is not necessarily a problem in these IBL applications that work with small ion doses. Here we provide a comprehensive review of ion beam lithography in general and a practical guide to the individual IBL techniques developed to date. Special attention is given to applications in nanofabrication

National Center for Advanced Information Components Manufacturing. Program summary report, Volume II

The National Center for Advanced Information Components Manufacturing focused on manufacturing research and development for flat panel displays, advanced lithography, microelectronics, and optoelectronics. This report provides an overview of the program, program history, summaries of the technical projects, and key program accomplishments

A system for automatic positioning and alignment of fiber-tip interferometers

The research described in this thesis involves the design, development, and implementation of an automated positioning system for fiber-optic interferometric sensors. The Fiber-Tip Interferometer (FTI) is an essential component in the proven Thermo-Acousto-Photonic NDE technique for characterizing a wide range of engineering materials including polymers, semiconductors and composites. The need to adapt the fiber-optic interferometric system to an industrial environment and to achieve precision control for optimizing interferometric contrast motivated the development of an automated, self-aligning FTI system design. The design enables high-resolution positioning and alignment by eliminating manual subjectivity and allows significantly improved repeatability and accuracy to be attained. Opto-electronic and electromechanical devices including a GRIN lens, 2x2 fused bi-conical taper couplers, photodiodes, motor-controlled tip/tilt stages, oscilloscopes, and a PCI card, constitute a closed-loop system with a feedback controller. The system is controlled by and communicates with a computer console using LabVIEW, a graphical language developed by National Instruments. Specifically, alignment is quantified by scanning the voltage readings at various orientations of the GRIN lens. The experimental setup specific to achieving maximum interferometric contrast intensity when interrogating silicon wafers with various surface depositions is discussed. Results corresponding to the interferometric contrast data obtained at several different standoff distances (Fizeau Cavity magnitudes) demonstrate the robustness of the novel design