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The transdermal drug delivery device is a sophisticated system for delivering drugs continuously via the skin to the systemic circulation in the human body. Advanced technologies are needed to manufacture them at low costs in high volumes. The nanoimprint lithography (NIL) system made this possible. The system consists of NIL process to imprint a pattern on a foil with nano structure similar to a human cell structure, which covers the microneedles, and then it is followed by the laser cutting of the nanostructured foil to fit onto the microneedles device. This process ensures friendly reaction of the body cells to the external compound because the imprinted structure that covers the surface of the microneedles mimics’ cell structure. This transdermal drug delivery device has an advantage over the naked microneedles. The immune system does not respond to the system, it is painless, the system showed that the efficiency improved 200 times, and the system is sufficiently flexible and deformable, which permits the device to maintain agent-transmitting relationship upon such sensitive areas as the skin. Biosensor devices are another application that can be manufactured using NIL technology in low cost, high throughput, and low-energy consumption.

"Block X," located in offshore Sabah is operated by JX Nippon Oil & Gas Exploration (Deepwater Sabah) Limited., which had drilled several exploration wells and acquired extensive wireline and LWD information to evaluate the block for further exploration and future development. Drilling exploration wells in a deepwater environment can lead to drilling difficulties. For example, a very narrow safe mud weight window was encountered in the discovery Well X and subsequent drilling difficulties delayed the well delivery. In orderto minimize the drilling risk for upcoming prospects, detailed petrophysical, geological and geomechanical studies have been conducted based on extensive evaluation of wireline and LWD data. Determination of horizontal stress directions and magnitudes are an important part of building the 1D mechanical earth model, which allows optimizing perforation and completion design, and production planning. Knowledge of the stress directions also helps to optimize well trajectory design so that wellbore instability can be minimized. Several methods for identifying stress directions are available and investigated, including borehole breakout orientation and shear sonic anisotropy information. For complementing the existing drilling data (leak-off and formation integrity tests), the horizontal stress magnitudes are determined using the dipole radial profiles and the sonic anisotropy using acoustoelasticity theory. The variation in shear sonic slowness within the elastic region of the rock is compared to the stress distribution caused by the presence of the wellbore. The relationship between shear slowness (modulus) and stress is then established to provide the acoustoelastic coefficient and horizontal stress magnitudes (both minimum and maximum) are then determined. These results were used to reduce uncertainty in the state of stress, and used in optimizing the wellbore trajectories for future development wells. In the current study, besides conventional stress calibration data such as LOT/FIT and calliper information, advanced sonic information helped to calibrate further the stress profile, which resulted in a comprehensive understanding of the stress regime of the study area. These results are utilized to better design the mud weight program for the drilling of future Deepwater prospects in Block X.

We report on the fabrication, integration, and simulation, both optical and optoelectrical, of two-dimensional photonic nanostructures for advanced light trapping in thin crystalline silicon (c-Si) solar cells. The photonic nanostructures are fabricated by the combination of various lithography (nanoimprint, laser interference, and hole mask colloidal) and etching (dry plasma and wet chemical) techniques. The nanopatterning possibilities thus range from periodic to random corrugations and from inverted nanopyramids to high aspect ratio profiles. Optically, the nanopatterning results in better performance than the standard pyramid texturing, showing a more robust behavior with respect to light incidence angle. Electrically, wet etching results in higher minority carrier lifetimes compared to dry etching. From the integration of the photonic nanostructures into a micron-thin c-Si solar cell certain factors limiting the efficiencies are identified. More precisely: (a) the parasitic absorption is limiting the short circuit current, (b) the conformality of thin-film coatings on the nanopatterned surface is limiting the fill factor, and (c) the material damage from dry etching is limiting the open circuit voltage. From optical simulations, the optimal pattern parameters are identified. From optoelectrical simulations, cell design considerations are discussed, suggesting to position the junction on the opposite side of the nanopattern.

A simple method for replicating metallic stamp from original masters via combined nanoimprint and electroforming is presented. In this work we demonstrate the generality of the method by replicating structures with dimensions ranged from several microns to sub-100nm in large patterned area. The structures were transferred first into an intermediate polymer sheet (IPS) with good uniformity and high structural fidelity, and then this IPS was used as the galvano-template for nickel electroforming. The major advantage of the method relies on the pattern transfer occurred between a soft polymer and the hard master, thereby the risk of damaging the mold is extremely low.

Nanoimprint lithography (NIL) has developed from an emerging nanoreplication technology into a mature and industrially viable manufacturing technology. It is now by far the fastest and most cost-efficient nanoreplication method available. This technology has been successfully implemented in the manufacturing of High Brightness LED's. However, manufacturing of HBLED's in high volume using nanoimprint lithography faces a few particular challenges. Perhaps the most significant is to produce perfectly imprinted nanostructures on the epitaxially grown substrates with high quality and yield. This is especially important since the substrates are expensive and since the imprint step is close to the end of the production process. This means that the value of the processed substrates is very high. In this work, 8000 imprints were produced. Measured data from the imprinted substrates shows consistent results. It is also shown that the 8000 imprints have been performed using the same stamp without significant degradation. After 8000 imprints, the yield from the nanoimprint lithography step is 99.15%.

Real Time Drilling Geomechanics (RTDG) provides relevant real time information and integrated workflow to help clients in reducing operational risk and nonproductive time (NPT) through drilling in marginal economical and technically challenging environments. Dulang-B field is a technical challenge due to its complex structural geological environment. All the existing wells failed to penetrate into deep reservoir F40 sands due to wellbore instabilities issues. Overpressure in F-sands remains always the main concern and challenge which led to unsafe drilling environment and significant nonproductive time in the field. Avoiding drilling surprises means more than being prepared for problems when they occur; it means averting them in the first place. Appropriate safe mud weight to drill each formation, must be defined to overcome different overpressure zones and identify the best position for casing seat of each hole section of the well. With the knowledge acquired through pore pressure and fracture gradient modeling, well behavior could be foretold with enough advance notice to allow drilling team to calmly make technically sound operational decisions that lead to optimal drilling performance. This study presents the challenges and the main results of the collaborative drilling approach via RTDG (Real Time Drilling Geomechanics) operation in well DL-B28 ST2. This study focuses on the overpressure and narrow safe mud weight window as well as level of uncertainty over prognosis formation tops which has to be managed by integrating LWD seismicVISION* and RTDG which had clear impacts on decision making process. The real time measurement approach by utilizing actual well data provided the best solution to accurately constrain pre-drill pore pressure and fracture gradient model.

A complete nanobiosensor structure consisting of a 200 @mm x 200 @mm area containing 100 nm sized interdigitated nanoelectrodes with varied interelectrode distances has been fabricated using nanoimprint lithography (NIL) in combination with UV-lithography. The complete structure has been characterized with admittance spectroscopy. In the paper are discussed the needs and key issues for nanosensors and the capability offered by using NIL for fabrication of such sensors.

Nano Imprint Lithography (NIL) is a promising technology that combines low costs with high throughput for fabrication of sub 100 nm scale features. One of the first application areas in which NIL is used is manufacturing of various types of LED's. The wafers used for producing LED's are typically III/V semiconductor materials grown with epitaxial processes. These types of substrates suffer from growth defects like hexagonal spikes, vpits, waferbowing, atomic steps and surface corrugations on a scale of few 10 μm or even large islands of irregularities. The mentioned irregularities are particularly disturbing when NIL based processes are utilized to create patterns onto the wafer surface. The nanopatterns created by NIL can be applied to control metal organic vapour phase epitaxy (MOVPE) growth of GaN nanorods. This paper will show that NIL is an excellent technology to produce nanopatterned GaN substrates highly suitable to grow defect free arrays of positioncontrolled nanorods for ultrahigh brightness LED applications.

In order to realize industrial level manufacturing using Nano Imprint Lithography, one of the key challenges is to supply stamps for the high volume machines. The master stamp is typically time consuming to produce and thus very expensive. It is therefore preferable to produce the maximum amount of replicated stamp from a master and to ensure that each stamp replica can deliver as many imprints as possible without losing yield. Currently, stamp replication is an area of intense development. How to produce a replicated a stamp and how many replicas that can be achieved from each master depend both on feature sizes, pattern density as well as aspect ratio of the structures. Several different techniques can be combined in order to obtain a large number of stamp replicas from each master. The ability to combine several different techniques enables the choice of the ideal technique suited for each structure type. This paper will focus on how to address stamp replication challenges in order to secure an adequate supply of stamps to enable high volume manufacturing with Nano Imprint Lithography. Results will be presented on the number of stamps that can be manufactured from each master as well as the lifetime of each individual stamp.

Introduction Thoracoabdominal aortic aneurysms usually present in elderly patients with serious renal, pulmonary, cerebral, or cardiac comorbidities that pose a great challenge to the attending surgeon. Endovascular techniques for the treatment of thoracoabdominal aneurysms are not yet widely used due to limitations associated with them, such as spinal and visceral ischemia. Case presentation An 87-year-old Caucasian man with a symptomatic Crawford type I thoracoabdominal aortic aneurysm was treated successfully with a long tube stent graft using endovascular techniques and without any complication in follow-up examinations. The stent was placed distal to the left subclavian artery, and proximal to the celiac axis. Conclusion The use of endovascular stents for long segment thoracoabdominal aortic aneurysms needs to undergo clinical investigation to determine whether this procedure decreases morbidity and mortality rates.

This study investigates a non-destructive optical metrology technique, that furnishes measurement solutions for hard drive discrete track recording (DTR) and bit patterned media (BPM) templates and imprints. From the measurement and analysis of polarized reflectance and transmittance, feature height and profile of DTR and BPM templates and imprints, as well as residual layer thickness of imprints, are accurately determined, and uniformity maps of these parameters are produced in a fraction of a minute. Simulations of theoretical polarized reflectance and transmittance, relating to next generation structures, demonstrate that the optical metrology solution has capability for future products.

The increased requirement e.g. resolution in multimedia displays creates the need for more storage capacity in both optical discs as well as hard drives. Blu-Ray-ROM and particularly future optical media formats require the employment of new lithography technologies. Today's magnetic media technology is facing difficulties to continue to higher surface densities and larger capacities due to the superparamagnetic limit. By using isolated magnetic domains to store the data, making it possible to get beyond 500 Gbits/in 2 densities. The approach we describe uses a unique direct-write electron beam lithography system for lithography on a rotating substrate and creates a patterned master disc, which can be used as a mold in replication of final disks by imprint lithography. The imprint process replicates the original pattern with an exceptionally fast turn around time, making mass production of optical and magnetic media possible. However, realization of these new technologies offers challenges in implementation.

Nanoimprint lithography (NIL) is a very interesting technique for biotechnological applications due to the fact that nanostructures can reproducible be formed at a low cost. The real massive exploration of nanotechnology in biotechnological applications has not been hindered by lack of ideas of what to do but more about how to get it done at a sufficiently low cost. Biotechnology has for many years taken up technologies from microelectronics when their life time in the microelectronics arena has been completed. However, with the introduction of nanoimprint lithography a new scenario is established and it is possible for the biotechnological community to produce various kinds of advanced nanostructured surfaces without the need to build up a complete nanotechnology process line and without the need to take over used equipment from the microelectronics labs. Nevertheless, the NIL technique has not yet been widely adapted by the biotechnology community. The reason for this is first of all being due to small exposure of this technique to the biocommunity. This is however rapidly changing right now thanks to the worldwide boost of nanotechnology that presently is taking place, partly due to the US Nanotechnology Initiative that in turn made Asian and European governments and research organizations to launch similar kind of large programs devoted to nanotechnology and -science.

Nanoimprint lithography (NIL) got large attention when it was introduced 1, 2 since it de-scribed the possibility for a low cost parallel nanotechnology. It got even larger attention when it was reported that sub 10 nm features on a Si stamp could be replicated into a resist layer, which in turn had a profile allowing a lift-off process to be possible.3,4 More reports about NIL technology followed and soon also devices were reported made with NIL. 5, 6, 7 This development inspired a few research groups to initiate projects around NIL technology. Also related techniques such as micro contact printing and its relatives were further developed at this time. 8, 9 Several different nanoimprint machines, set-ups and processes were reported. Examples of this rich development are for instance the roller imprint, 10 Step and flash imprint lithography, 11 described multi-layer resist methods. 12 An interesting observation is that in most of the works reported so far (except the early works in ref. 2,3 above) the feature sizes have rather been closer to the 100 nm domain than to the 10 nm domain. Furthermore in most of the NIL experiments reported the de-scribed were made with stamps having areas of only one or a few square centimetre(s).1, 2, 3, 4, 5, 6, 7 In order to meet the demand from industries, there was thus a need to develop a large area NIL process.13 Here two alternatives exists, either use a full wafer single printing step procedure 14, 15, 16 or to utilize a step & repeat procedure.17 Still up to now, more than seven years ago after its introduction, very few reports of real large wafer scale NIL exists. The largest size of the wafers successfully printed is 6 inch 14, 15 and for these experiments two kinds of stamps has been used. The stamp was either a metal CD-master stamp or an de-scribed defined electroplated metal stamp having regions with lines at the nanometer scale distributed at few locations over the wafer. The printed pattern definition in the resist to be accurate.

Nanoimprint lithography over 2 inch wafers with a patterned area of 40,000 micrometer squared consisting of interdigitated lines of 100 nm width with varying distance between the lines has been performed. By performing metal lift-off and subsequent UV-lithography for definition of contact regions and pads, complete metal arrays have been fabricated. The structure is electrically characterized by admittance spectroscopy. In this paper we describe the design and realization of a compact nanoimprint lithography system. Furthermore, various aspects of nanoimprint lithography are discussed, and nanoimprint lithography is compared with other nanostructuring technologies.

Nanoimprint lithography (NIL) is a nonconventional lithographic technique that promises low-cost, high-throughput patterning of structures with sub-10 nm resolution. Contamination of nanoimprint stamps is one of the key obstacles to industrialize the NIL technology. Here, we report two efficient approaches for removal of typical contamination of particles and residual resist from stamps: thermal and ultraviolet (UV) imprinting cleaning-both based on the self-cleaning effect of imprinting process. The contaminated stamps were imprinted onto polymer substrates and after demolding, they were treated with an organic solvent. The images of the stamp before and after the cleaning processes show that the two cleaning approaches can effectively remove contamination from stamps without destroying the stamp structures. The contact angles of the stamp before and after the cleaning processes indicate that the cleaning methods do not significantly degrade the anti-sticking layer. The cleaning processes reported in this work could also be used for substrate cleaning.

We demonstrate the nanoimprint lithography (NIL) technique with sub 100 nm resolution, on 6 in. Si substrates. The pattern transfer is performed using a specially designed NIL machine optimized to achieve a very high degree of parallelism between stamp and substrate. The stamp is made with the help of electron beam lithography and Ni electroplating achieving features below 100 nm in size. The nanoimprint process is done in a single layer as well as in a multilayer resist scheme with subsequent O2-plasma etching and metal lift-off.

Nanoimprint lithography is a promising technique for fabrication of nanometer-sized structures with an eventual throughput capacity similar to UV-lithography based production of integrated circuits. In this article we address the possibility for wafer scale nanoimprint lithography, and the results presented here are all obtained from 2 in. sized substrate and stamp wafers. Our nanoimprint lithography equipment is described and some of its characteristics are discussed. These include ultrafast imprint cycle times of less than 2 min, good temperature monitoring, and control possibility of the substrate temperature. We show complete results after imprint, removal of remaining resist, and liftoff for 2 in. wafers. Furthermore, in this article the relation between polymer sticking to the stamp applied pressure, stamp depth, etc. is studied in detail.