Photomask / Direct Write Lithography Documents

The resolution of Fresnel zone plate (FZP) as X-ray lens is determined by the width of outer-most zone, and the diameter of condenser lens is desirable to be large so that bright x-ray beam is available in x-ray optical systems. As the diameter of FZPs with nm resolution reported so far is small, typically less than 0.2mm, FZPs cannot be used as effective condenser lens.

We studied various types of 2D and 3D Si-based photonic crystal structures that are promising for future photonic integrated circuit application. With regard to 2D SOI photonic crystal slabs, we confirmed the formation of a wide photonic bandgap at optical communication wavelengths, and used structural tuning to realize efficient single-mode line-defect waveguides operating within the bandgap. As regards 3D photonic crystals, we used a combination of lithography and the autocloning deposition method to realize complicated 3D structures. We used this strategy to fabricate 3D full-gap photonic crystals and 3D/2D hybrid photonic crystals.

The transmittance spectrum for an air-bridge type of AlGaAs photonic crystal (PC) slabs successfully fabricated was measured. It is found that the observed spectrum is consistent with both the theoretical band structure and the calculated one. Moreover, the transmittance due to the modes below the light line is found to be almost 100%, indicating that the guided modes should exist.

Diamond molds were fabricated by two types of fabrication processes, both of which use a conductive intermediate layer between the diamond surface and polymethylmethacrylate (PMMA) resist to prevent surface charge-up.

Nanoimprint lithography is an attractive technology for LSIs era below 40-nm critical dimension from the viewpoint of high-throughput and low-cost equipment. In order to avoid a pattern placement error due to thermal expansion in the conventional thermal imprint process, we attempted to replicate the mold pattern onto a liquid polymer, which was solidified using ultra-violet (UV) light irradiation at room temperature.

This tutorial will address key issues of nanofabrication for biocompatible substrates. A review of the nanofabrication techniques suitable for patterning biocompatible materials will be given. The emphasis will be put on the effect of controlled surface topography on cell adhesion, growth and motility. Applications including in vitro engineered tissues and bone cells optimally grown on biodegradable templates will be described. A brief introduction to emerging biochips will then be given.

New Jersey Nanotechnology Consortium

A Fresnel lens is a chromatic, but low-loss optic, that can be used as a hard x-ray focusing element. In order to maintain phase coherence across the lens for a given x-ray wavelength, and to maximize transmission, material is deleted that removes multiples of 2 pi phase-shift. Using planar micro-electronics technology we have fabricated refractive Fresnel lenses for hard X-rays in single crystal silicon, and with the ideal shape.

Zone plates are the key focusing element for many x-ray (7–20 keV) and soft x-ray (200–500 eV) applications, yet, production with electron-beam lithography poses obstacles to their widespread availability. In addition, fabrication processes to date have limited the studies of amplitude Bragg– Fresnel-type elements in the hard x-ray regime. We report new processes that couple 100 keV electron-beam lithography with established production methods to achieve two goals: (1) improving the overall yield and volume of ultrahigh-resolution soft x-ray zone plates and (2) applying deep silicon etching techniques to extend the state of the art in high aspect ratio Bragg–Fresnel optics required to create high efficiency focusing of high-energy x rays.

We evaluated the performance of 100-kV point electron-beam lithography system: JBX-9300FS and developed Mix and Match lithography process. Resolution on resist exposure is 30-nm using commercially available chemically amplified resist and is down to 10-nm-order using Calixarene resist. For high-throughput lithography, Mix-and-Match lithography process was developed including pattern preparation, and EB exposure time decreased in 1/3. These process technologies are useful for development advanced CMOS devices.