Functional polymeric films with antireflective and hydrophobic properties have been widely used for electronic device displays. However, the design of such functional films with an antimicrobial characteristic has been a challenge. We designed a nanostructured surface using a rigorous coupled-wave analysis to obtain a period of 300 nm and an aspect ratio of 3.0 on a flat poly(methyl methacrylate) film. The fabricated nanostructure was hydrophobic and exhibited the desired optical characteristics with a reflectance of less than 0.5% over the visible wavelength range. Furthermore, the nanoimprinted polymer film exhibited antimicrobial characteristics and low adhesion when compared with the corresponding flat surface. The results suggest that the nanostructured surface designed in this study is multifunctional and should be suitable for the production of protective optical and hygienic polymer films for the displays of portable electronic devices.

https://pubs.acs.org/doi/pdf/10.1021/am506254r

Nanostructured Multifunctional Surface with Antireflective and Antimicrobial Characteristics

Double patterning technology (DPT) is a most likely lithography solution for 32/22 nm technology nodes as of 2008 due to the delay of extreme ultra violet lithography. However, it should hurdle two challenges before being introduced to mass production, layout decomposition and overlay error. In this paper, we present the first detailed routing algorithm for DPT to improve layout decomposability and robustness against overlay error, by minimizing indecomposable wirelength and the number of stitches. Experimental results show that the proposed approach improves the quality of layout significantly in terms of decomposability and the number of stitches with 3.6x speedup, compared with a current industrial DPT design flow.

/pdf/double-patterning-technology-friendly-detailed-routing-4yzh93t5gd.pdf

Double patterning technology friendly detailed routing

As technology continues to scale to 14nm node, Double Patterning Lithography (DPL) is pushed to near its limit. Triple Patterning Lithography (TPL) is a considerable and natural extension along the paradigm of DPL. With an extra mask to accommodate the features, TPL can be used to eliminate the unresolvable conflicts and minimize the number of stitches, which are pervasive in DPL process, and thus smoothen the layout decomposition step. Considering TPL during routing stage explores a larger solution space and can further improve the layout decomposability. In this paper, we propose the first triple patterning aware detailed routing scheme, and compare its performance with the double patterning version in 14nm node. Experimental results show that, using TPL, the conflicts can be resolved much more easily and the stitches can be significantly reduced in contrast to DPL.

Triple patterning aware routing and its comparison with double patterning aware routing in 14nm technology

Double patterning technology (DPT) has emerged as the most hopeful candidate for the next technology node of the ITRS roadmap [1]. The goal of a DPT decomposer is to decompose the entire layout on each layer onto two masks. It assigns two features to different masks if their spacing is less than a predefined threshold. Besides, some features must be sliced and put onto two masks so that there would be a feasible solution for mask assignment. Such slicing will cause stitches that affect yield. So decomposer needs to minimize their number. In this paper, we formulate the DPT decomposition problem as a maximum cut problem. We propose an extremely efficient two-stage decomposition algorithm called GREMA. The first stage of GREMA generates a set of candidate stitches to ensure that feasible solutions exist for DPT decomposition. The second stage uses maximum cut to find the minimal set of stitches. Our decomposer is able to solve much larger realistic design problems. Experiments demonstrated that GREMA achieved great performance on resolving conflicts with greatly reduced runtime.

GREMA: graph reduction based efficient mask assignment for double patterning technology

Double Patterning Lithography (DPL) is one of the few hopeful candidate solutions for the lithography for CMOS process beyond 45nm. DPL assigns the patterns less than a certain distance from each other on each layer onto two masks instead of one mask in traditional lithography. In this paper, we prove that the conflict graph used to model DPL conflicts in layout is a planar graph. Based on the planarity of the conflict graph, we propose a new face merging based framework which formulates DPL decomposition as a problem of pairing odd faces to simultaneously inimize the number of stitches generated and conflicts to eliminate. We employ partitioning and simplification techniques to reduce the problem size and use an O(n3) time maximum weighted matching algorithm to generate an optimal DPL decomposition.

/pdf/a-matching-based-decomposer-for-double-patterning-1hr8vzhpby.pdf

A matching based decomposer for double patterning lithography

PROBLEM TO BE SOLVED: To provide an imprint method and an imprint device capable of satisfying a transfer environment with specific gas suitable for transfer by suppressing volatilization of a photo-curing resin coated on a transferred substrate by an inkjet method, excellently holding wet spread of the resin during transferring, and maintaining cleanliness of the transfer environmentSOLUTION: Disclosed is an imprint method in which, using a template having an uneven pattern formed thereon, the pattern of the template is imprinted on and transferred to a photo-curing resin on a transferred substrate During standby when an imprint is not performed, to a space part in which the template and the photo-curing resin come into contact with each other, clean air is sent from a blow port, and during imprinting, flow rate of clean air in the space part is reduced or the clean air is prevented from being sent

Imprint method and imprint device

PROBLEM TO BE SOLVED: To provide an imprinting method and an imprinting device attaining stable imprinted transcription of high definition.SOLUTION: In the supply step, a resin material 5 is supplied to at least one of a surface 1a having a rugged structure region 1A of a mold 1 and a filling base material 11, in the filling step, the resin material 5 is filled between the surface 1a of the mold 1 and the filling base material 11, in the separating step, the filling base material 11 is separated from the mold 1 so as to remain the resin material 5 on the mold 1 side, in the pushing step, an imprinting substrate 7 is brought into contact with the resin material 5, in the mold-releasing step, the mold 1 is pulled apart from the resin material 5, so as to establish a relation θk<θm<θj among the contact angle θm of the resin material 5 to the mold 1, the contact angle θj of the resin material 5 to the filling base material 11, and the contact angle θk of the resin material 5 to the imprinting substrate 7.

Imprinting method and imprinting device

Provided are: an imprinting method which suppresses volatilization of a photocurable resin applied on a transfer-receiving substrate by an inkjet method, satisfactorily maintains the wet-spreading property of the resin at the time of transfer, maintains cleanness of the environment for transfer, and can fill the environment for transfer with a particular gas appropriate for transfer; and an imprinting apparatus. Disclosed is an imprinting method of using a template having a concavo-convex pattern formed thereon, and transferring the pattern of the template by imprinting to a photocurable resin on a transfer-receiving substrate, characterized in that, in a space where the template and the photocurable resin are brought into contact, clean air is sent to the space through an air blowing port during a standby mode of not performing imprinting, and the flow rate of clean air in the space is reduced or clean air is not sent during an imprinting mode.

Imprinting method and imprinting apparatus

PROBLEM TO BE SOLVED: To provide a mold for imprinting, an alignment method, an imprinting method, and an imprinting device capable of performing alignment with high accuracy by making it possible to directly and optically recognize an alignment mark made of the same material as a mold material without requiring a complicated process for manufacturing the mold.SOLUTION: In step and repeat type imprinting, an alignment mark on the mold side is formed at a position parted from a groove structure on the same plane as the transcription region of the mold, and is not aligned with the substrate side alignment mark in a transcribed region where imprinting is performed, but is aligned with the transcribed region vertically, horizontally, and diagonally brought into contact with the transcribed region.

Mold for imprinting, alignment method, imprinting method, and imprinting device

Double patterning technology (DPT) is one of the most practical candidate technologies for 45nm half-pitch or beyond
while conventional single exposure (SE) is still dominant with hyper NA avoiding DPT difficulties such as split-conflict
or overlay issue. However small target dimension with hyper NA and strong illumination causes OPC difficulty and
small latitude of lithography and photomask fabricated with much tight specification are required for SE. Then there
must be double patterning (DP) approach even for SE available resolution.
In this paper DP for SE available resolution is evaluated on lithography performance, pattern decomposition, photomask
fabrication and inspection load.
DP includes pattern pitch doubled of SE, then lithography condition such as mask error enhancement factor (MEEF) is
less impacted and the lower MEEF means less tight specification for photomask fabrication.
By using Synopsys DPT software, there are no software-induced conflicts and stitching is treated to be less impact. And
also this software detects split-conflicts such as triangle or square placement from contact spacing.
For estimating photomask inspection load, programmed defect pattern and circuit pattern on binary mask are prepared.
Smaller MEEF leads less impact to defect printing which is confirmed with AIMS evaluation. As an inspection result,
there are few differences of defect sensitivity for only dense features and also few differences of false defect counts
between SE and DP with less NA. But if higher NA used, DP's inspection sensitivity is able to be lowered Then
inspection load for DP would be lighter than SE.

Takaharu Nagai

Papers

Imprint method and imprint device

Imprinting method and imprinting device

Imprinting method and imprinting apparatus

Mold for imprinting, alignment method, imprinting method, and imprinting device

Decomposition difficulty analysis for double patterning and the impact on photomask manufacturability