| 1. |
- Pfeiffer, K, et al.
(author)
-
Polymer stamps for nanoimprinting
- 2002
-
In: Microelectronic Engineering. - 1873-5568. ; 61-2, s. 393-398
-
Journal article (peer-reviewed)abstract
- Stamp fabrication for nanoimprinting can be significantly simplified, when specialized crosslinking polymers are applied to pattern definition. The polymer patterns can be used as stamps themselves. Two possibilities are reported: (1) An e-beam sensitive resist was developed, which enables the fabrication of polymer-on-silicon stamps. Patterns with a feature size of 70 nm could be created. (2) Full plastic stamps were obtained by a casting-moulding technique, which enable pattern transfer from any conventional mould. The quality of the two stamp variants were proved by imprinting experiments. (C) 2002 Elsevier Science B.V. All rights reserved.
|
|
| 2. |
- Ameen, Carly, et al.
(author)
-
Specialized sledge dogs accompanied Inuit dispersal across the North American Arctic
- 2019
-
In: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 286:1916
-
Journal article (peer-reviewed)abstract
- Domestic dogs have been central to life in the North American Arctic for millennia. The ancestors of the Inuit were the first to introduce the widespread usage of dog sledge transportation technology to the Americas, but whether the Inuit adopted local Palaeo-Inuit dogs or introduced a new dog population to the region remains unknown. To test these hypotheses, we generated mitochondrial DNA and geometric morphometric data of skull and dental elements from a total of 922 North American Arctic dogs and wolves spanning over 4500 years. Our analyses revealed that dogs from Inuit sites dating from 2000 BP possess morphological and genetic signatures that distinguish them from earlier Palaeo-Inuit dogs, and identified a novel mitochondrial clade in eastern Siberia and Alaska. The genetic legacy of these Inuit dogs survives today in modern Arctic sledge dogs despite phenotypic differences between archaeological and modern Arctic dogs. Together, our data reveal that Inuit dogs derive from a secondary pre-contact migration of dogs distinct from Palaeo-Inuit dogs, and probably aided the Inuit expansion across the North American Arctic beginning around 1000 BP.
|
|
| 3. |
- Carlberg, Patrick, et al.
(author)
-
Nanoimprint in mr-L 6000.1 XP/PMMA resist system
- 2002
-
In: 7th International Conference on Nanometer-Scale Science and Technology and 21st European Conference on Surface Science.
-
Conference paper (peer-reviewed)abstract
- Use of the new resist system mr-L 6000.1 XP in combination with PMMA is demonstrated to give sub-100 nm resolution in nanoimprint lithography. Low glass transition temperature in combination with high plasma stability makes this resist suitable for achieving desirable resist profiles after the imprint process. Imprint conditions for mr-L 6000.1 XP/PMMA resist system as well as imprint results are described and discussed
|
|
| 4. |
- Finder, C, et al.
(author)
-
Fluorescence microscopy for quality control in nanoimprint lithography
- 2003
-
In: Microelectronic Engineering (Proceedings of the 28th International Conference on Micro- and Nano-Engineering). - 0167-9317 .- 1873-5568. ; 67-8, s. 623-628
-
Conference paper (peer-reviewed)abstract
- Fluorescence microscopy is introduced as a low cost quality control process for nanoimprint lithography. To depict imprinted structures down to 1 mum lateral size and to detect residues down to 100 nm lateral size, the standard printable polymer mr-18000 is labelled with less than 0.1 wt.% fluorescent dye. Three different types of stamps are used to determine the dependence of the shape and size of stamp features in a series of imprints. The quality of a stamp is given by the sticking polymer residues per unit area. Fluorescence light images as well as visible light images are analysed. Changes in the area of the stamp covered with polymer as a function of the number of imprints is summarised in a statistical process chart. Adhesion was artificially induced in order to observe self cleaning of virgin stamps. They were detected and monitored, suggesting that this method is a suitable technique for quality control and that it could be easily adapted to the nanoimprint process. (C) 2003 Elsevier Science B.V. All rights reserved.
|
|
| 5. |
- Maximov, Ivan, et al.
(author)
-
New high resolution negative resist mr-L 6000.1 XP for electron beam and nanoimprint lithography
- 2002
-
In: 7th International Conference on Nanometer-Scale Science and Technology and 21st European Conference on Surface Science.
-
Conference paper (peer-reviewed)abstract
- We present the characterization results of a new high resolution negative electron beam resist mr-L 6000.1 XP. The resist can also be used as imprintable polymer in nanoimprint lithography with sub-100 nm resolution. The feature size achieved after e-beam exposure was about 50 nm with sensitivity of 2-4 μC/cm2. Studies of the resist properties as a function of chemical composition and development conditions are also presented
|
|
| 6. |
- Pfeiffer, K, et al.
(author)
-
A comparison of thermally and photochemically cross-linked polymers for nanoimprinting
- 2003
-
In: Microelectronic Engineering. - 1873-5568. ; 67-8, s. 266-273
-
Journal article (peer-reviewed)abstract
- The characteristics and benefits of two types of cross-linking prepolymers with low glass transition temperature (T-g) for nanoimprinting are reported. They are soluble in organic solvents and their solutions can be processed like those of common thermoplastics. The imprinted patterns receive high thermal and mechanical stability through cross-linking polymerization. The course of the polymerization was investigated to determine the appropriate conditions for the imprint process. In thermally cross-linked polymers mr-I 9000, the cross-linking occurs during imprinting. Process time and temperature depend on the polymerization rate. Volume shrinkage during the polymerization does not adversely affect imprinting. Photochemically cross-linked polymers mr-L 6000 make possible imprint temperatures below 100 T and short imprint times. The T-g of the prepolymer determines the imprint temperature. The cross-linking reaction and structural stabilization is performed after imprinting. 50-nm trenches and sub-50-nm dots confirm the successful application of the polymers.
|
|
