The continuing trend toward higher circuit density in microelectronic devices has motivated research efforts in varieties of high-resolution lithography techniques, including electron beam (EB), X-ray, and deep UV irradiation. Use of ultra-thin films and new materials have been proposed as approaches to improve resolution in lithography. The Langmuir-Blodgett (LB) technique is very effective method used to prepare well-defined ultra-thin film with controlled thickness and orientation at a molecular level. Therefore, LB films are expected to realize ultra-high resolution photolithography [1-4].
In previous studies, [5-7] we have found that N-octadecylacrylamide forms a uniform LB film with a highly ordered structure, and yielded a fine negative pattern by photopolymerization. Furthermore, we have also succeeded in the preparation of preformed polymer LB film that has a cross-linking group . By the cross-linking reaction with deep UV and electron beam irradiation we obtained a fine negative pattern consisting of two-dimensional network. All of these polymer LB films resulted in negative-tone photopatterns. On the other hand, we also obtained positive type photopatterns using poly(N-tetradecylmethacrylamide)(p(TDMA)) LB films without any development process (self-development) [9, 10]. It was found that the higher sensitivity could be obtained by changing the alkyl side chain to the short-branched type . In addition, the deprotection reaction of t-butoxycarbonyloxy group has also been used in positive patterning of polymer LB films [12-14]. Combining these interesting properties, the improvement of not only the sensitivity but also the imaging quality can be expected. In this work, we prepared the copolymers of photodegradable N-tetradecylmethacrylamide (TDMA) with t-butyl 4-vinylphenyl carbonate (tBVPC) (Figure 1) aiming at the fabrication of a new type of positive resist taking place both main chain scission and polarity change caused by t-butoxycarbonyloxy group deprotection.
Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously
17.01.2017 | Sonderforschungsbereich 668
Manchester scientists tie the tightest knot ever achieved
13.01.2017 | University of Manchester
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.
The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
17.01.2017 | Earth Sciences
17.01.2017 | Materials Sciences
17.01.2017 | Architecture and Construction