In this paper, we report a general method for imprinting nanometer-scale features in low-viscosity photosensitive hydrogels using conventional optical mask aligner technology. We call this method flash imprint lithography using a mask aligner (FILM). The FILM process makes it possible to fabricate nanometer-scale features in ultraviolet (UV)-curable hydrogels quickly, inexpensively and reproducibly. We believe that the FILM process will be useful in many areas of research but is particularly applicable to tissue engineering. Accordingly, we demonstrate the FILM process by imprinting dense arrays of nanostructures in polyethylene glycol dimethacrylate (PEGDMA), a material commonly utilized as a substrate in micro-and nanoscale tissue scaffolds; finite element modeling and contact angle analysis are employed to characterize pattern transfer of low-viscosity polymers (e.g. PEGDMA) in the FILM process.

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Although the diffusion control and dopant activation of Ge p-type junctions are straightforward when using B+ implantation, the use of the heavier BF2+ ions or even BF+ is still favored in terms of shallow junction formation and throughput—because implants can be done at higher energies, which can give higher beam currents and beam stability—and thus the understanding of the effect of F co-doping becomes important. In this work, we have investigated diffusion and end-of-range (EOR) defect formation for B+, BF+, and BF2+ implants in crystalline and pre-amorphized Ge, employing rapid thermal annealing at 600 °C and 800 °C for 10 s. It is demonstrated that the diffusion of B is strongly influenced by the temperature, the presence of F, and the depth of amorphous/crystalline interface. The B and F diffusion profiles suggest the formation of B–F complexes and enhanced diffusion by interaction with point defects. In addition, the strong chemical effect of F is found only for B in Ge, while such an effect is vanishingly small for samples implanted with F alone, or co-implanted with P and F, as evidenced by the high residual F concentration in the B-doped samples after annealing. After 600 °C annealing for 10 s, interstitial-induced compressive strain was still observed in the EOR region for the sample implanted with BF+, as measured by X-ray diffraction. Further analysis by cross-sectional transmission electron microscopy showed that the {311} interstitial clusters are the majority type of EOR defects. The impact of these {311} defects on the electrical performance of Ge p+/n junctions formed by BF+ implantation was evaluated.

We report the use of Step & Flash Imprint Lithography reverse tone (SFIL-R TM ) and liftoff technique to fabricate sub-100nm metal nano-wires as the electrodes for Room Temperature Single Electron Transistors (RT-SET). The optimized process flow was performed on approximately 300 imprints, for a total of 714,000 devices. Each imprinted device contains Drain/Source/Gate electrodes. Multiple electrode geometries were designed to explore the impact of device parameters. Following electrode formation, Tungsten quantum dots (QD) were formed using a novel Focus Ion Beam (FIB) deposition technique, resulting in room temperature single electron transistor (RT-SET) devices. The RT-SET devices are tested using a Keithley 4200-SCS semiconductor parametric analyzer.

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