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Herein, we present the results of a systematic material development study we carried out in order to obtain a new positive tone resist for high resolution electron-beam lithography. Several acrylic copolymer materials with different mass fractions of the comonomers, different molecular weights and similar molecular weight distributions were synthesized and - as resist solutions - evaluated in terms of electron-beam lithography performance. On the one hand, within the ranges investigated, it was shown that the lithographic sensitivity is significantly influenced by the composition rather than by the molecular weight or molecular weight distribution. On the other hand, the etch resistance of the materials remains unaffected by changes of these parameters. The resist material exhibiting the best combination of the desired properties, mr-PosEBR, is 2 times more sensitive than PMMA (495kDa) and performs comparably to the known high resolution resist ZEP520A. For example, a grating pattern with 29nm wide lines with a period of 100nm could be generated in films of mr-PosEBR with an area dose of 100µC/cm2. In terms of resolution, single lines of only 35nm width could be fabricated via metal lift-off using 100kV EBL. Furthermore, the dry etch stability of mr-PosEBR in a reactive-ion etching (RIE) process (etch gases: CF4/SF6) is similar to the one of ZEP520A (etch rates, mr-PosEBR: 190nm/min, ZEP520A: 150nm/min, silicon: 440nm/min). Moreover, high resolution nanopatterns in mr-PosEBR could be smoothly transferred into the underlying Si substrate by a RIE process. Display Omitted A new resist material for high resolution electron-beam lithography is presented.The resist was developed by the systematic variation of its copolymeric composition.The new material provides high sensitivity, high resolution and high etch stability.

This work presents a new type of high-resolution dry-film resist laminates for the fabrication of extremely thick epoxy based polymer structures. Via a lamination process a resist thickness of up to d=360@mm can be applied by one single process step. Afterwards, the dry-film resist is patterned by standard UV-lithography. An epoxy based resist mixture which contains epoxy resins, reactive diluents, additives, and a photo acid generator is deposited onto a PET supporting film by doctor blading for fabrication of the resist film. The films can be cut defect-free into favoured sheet sizes. Currently, dry-film resists with a layer thickness of up to 400@mm can be produced reproducible. With the tested d=360@mm thick dry-film resist an aspect ratio of 15:1 (height:width) has been achieved. By lamination and UV-patterning of two layers resist a master for 700@mm thick electroplated Nickel structures was fabricated. Thereby, steep side walls with an angle deviation of @a

There are two basic types of nanoimprint lithography: hot embossing using thermoplastic or thermosetting polymers and UV-based nanoimprint lithography (UV-NIL) using UV-curable polymer systems. Since the interest in UV-NIL has been constantly increasing within the last years, the need of suitable low-viscosity resists has increased, too. The availability of such materials is one key element of the UV-NIL technology. In this contribution a novel, spin-coatable polymer system for UV-NIL is presented. Suitable polymer components were evaluated using photoDSC analysis. Their ratio was adjusted in such a way that the overall dynamic viscosity of the mixture remained low which was beneficial for the flow behaviour. Film thicknesses in the range of 150-500nm could be obtained by spin-coating. The new polymer system was characterised in UV-NIL processes and in plasma etching investigations. Imprinted micrometer as well as nanometer scale patterns with feature sizes in the range of 30nm to several microns are shown.

The use of working stamps for nanoimprint lithography is highly interesting for a number of reasons like an increased lifetime and often a better manufacturability of the master stamp. We present results on the use of Ormostamp as a material for working stamps in UV-NIL. Imprinting properties and anti-sticking treatments have been investigated. So far a minimum feature size of 50nm can be achieved.

Transparent stamps are an integral and crucial part of the UV-imprinting. Time consuming fabrication of quartz stamps increases the price of the technology. In the presented work a thermally stable transparent imprint stamp made of a novel hybrid polymer system is demonstrated. As a low-cost and highly efficient alternative the hybrid polymer stamp contributes to the acceptance and application of the nanoimprint technology. By using the UV-patternable inorganic-organic hybrid polymer quartz stamps might become superfluous in the UV-imprint process entirely, because transparent working stamps can be manufactured also with use of opaque silicon master stamps.