Nanoimprint lithography (NIL) is a nonconventional lithographic technique for high-throughput patterning of polymer nanostructures at great precision and at low costs. Unlike traditional lithographic approaches, which achieve pattern definition through the use of photons or electrons to modify the chemical and physical properties of the resist, NIL relies on direct mechanical deformation of the resist material and can therefore achieve resolutions beyond the limitations set by light diffraction or beam scattering that are encountered in conventional techniques. This Review covers the basic principles of nanoimprinting, with an emphasis on the requirements on materials for the imprinting mold, surface properties, and resist materials for successful and reliable nanostructure replication.

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Nanoimprint Lithography: Methods and Material Requirements**

An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Semiconductor device, and manufacturing method thereof

Metasurfaces: From microwaves to visible

The ability of microto nanometer-scale patterning on flexible substrates can enable many new applications in the area of photonics and organic electronics. A major roadblock has remained for many practical applications of patterned nanostructures, which is the throughput of nanopattern replication and the associated cost issues. Among the emerging techniques, nanoimprint lithography (NIL) clearly stands out as a promising technology for high-throughput and highresolution nanometer-scale patterning, which can achieve resolutions beyond the limitations set by light diffraction or beam scattering that are encountered in other traditional techniques. Developments in this area have enjoyed great momentum in the past decade and numerous applications, such as in Si electronics, organic electronics and photonics, magnetics, and biology have been exploited by many researchers. On the other hand, the current process and throughput in NIL (on the order of a few minutes per wafer) is still far from meeting the demands of many practical applications, especially in photonics, biotechnology, and organic optoelectronics. The concept of roller imprinting has been pursued by previous investigators as a means to improve speed. However, the procedure was to imprint a small piece of Si mold onto a Si substrate, which is not too different from that of conventional NIL except that a rod is used to apply pressure rather than a flat plate. The reverse nanoimprinting or nanotransfer printing methods produce positive-tone polymer or metal patterns, which in principle can also be applied to roll-to-roll printing processes. In addition, Lee et al. proposed a bilayer transfer process from a ‘‘rigiflex’’ mold to a Si wafer, and pointed out that the process can potentially be extended to a roller bilayer transfer process. However, these are yet to be demonstrated.

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High‐Speed Roll‐to‐Roll Nanoimprint Lithography on Flexible Plastic Substrates

A system includes a semiconductor device. The semiconductor device includes a first single crystal silicon layer comprising first transistors, first alignment marks, and at least one metal layer overlying the first single crystal silicon layer, wherein the at least one metal layer comprises copper or aluminum more than other materials; and a second single crystal silicon layer overlying the at least one metal layer. The second single crystal silicon layer comprises a plurality of second transistors arranged in substantially parallel bands. Each of a plurality of the bands comprises a portion of the second transistors along an axis in a repeating pattern.

System comprising a semiconductor device and structure

We report the fabrication of a 50 nm half-pitch wire grid polarizer with high performance using nanoimprint lithography. The device is a form of aluminium gratings on a glass substrate whose size of 5.5 cm × 5.5 cm is compatible with a microdisplay panel. A stamp with a pitch of 100 nm was fabricated on a silicon substrate using laser interference lithography and sidewall patterning. The imprint and the aluminium etching processes are optimized to realize uniform aluminium gratings with aspect ratio of 4. The polarization extinction ratio of the fabricated device is over 2000, with transmission of 85% at a wavelength of 450 nm, which is the highest value ever reported. This work demonstrates that nanoimprint lithography is a unique cost-effective solution for nanopatterning requirements in consumer electronics components.

https://iopscience.iop.org/article/10.1088/0957-4484/16/9/076/pdf

Fabrication of a 50 nm half-pitch wire grid polarizer using nanoimprint lithography

Fabrication of subwavelength aluminum wire grating using nanoimprint lithography and reactive ion etching

The present invention relates to a solar cell. The solar cell includes a substrate of a first conductive type, the substrate having a textured surface on which a plurality of projected portions are formed, and surfaces of the projected portions having at least one of a plurality of particles attached thereto and a plurality of depressions formed thereon; an emitter layer of a second conductive type opposite the first conductive type, the emitter layer being positioned in the substrate so that the emitter layer has the textured surface; an anti-reflection layer positioned on the emitter layer which has the textured surface and including at least one layer; a plurality of first electrodes electrically connected to the emitter layer; and at least one second electrode electrically connected to the substrate.

Solar cell and texturing method thereof

Nanoimprint technology for nano-structured optical devices

Eine Solarzelle umfasst ein Substrat, einen Emitter-Bereich, der bei dem Substrat angeordnet ist und einen ersten Schichtwiderstand hat, einen ersten hochdotierten Bereich, der bei dem Substrat angeordnet ist und einen kleineren zweiten Schichtwiderstand als der erste Schichtwiderstand hat, eine bei dem Substrat angeordnete und mit dem Emitter-Bereich und dem ersten hochdotierten Bereich verbundene erste Elektrode, und eine bei dem Substrat angeordnete und mit dem Substrat verbundene zweite Elektrode, wobei der erste hochdotierte Bereich die erste Elektrode kreuzt und mit der ersten Elektrode verbunden ist, eine obere Oberflache des ersten hochdotierten Bereichs von einer oberen Oberflache des Emitter-Bereichs in Richtung einer lichteinfallenden Oberflache des Substrats hervorsteht, und eine untere Oberflache des ersten hochdotierten Bereichs die gleiche Hohe wie eine untere Oberflache des Emitter-Bereichs hat.

Philwon Yoon

Papers

Fabrication of a 50 nm half-pitch wire grid polarizer using nanoimprint lithography

Fabrication of subwavelength aluminum wire grating using nanoimprint lithography and reactive ion etching

Solar cell and texturing method thereof

Nanoimprint technology for nano-structured optical devices

Solarzelle und verfahren zu ihrer herstellung