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Nanoimprint lithography (NIL) can generate well defined nanostructures with high efficiency and at very low cost. Molecular imprinting (MIP) is a "bottom-up" technique creating a polymer layer exhibiting structures with a molecular selectivity. Such polymer structures may be employed as molecular recognition sites for sensing applications. In this work, the authors combine NIL with MIP and they are able to obtain micro- and nanopatterns of polymer with features down to 100 nm that show high molecular selectivity., QC 20140922

The objective of this benchmarking is to establish a comparison of several tools and processes used in thermal NIL with Si stamps at the nanoscale among the authors' laboratories. The Si stamps have large arrays of 50 nm dense lines and were imprinted in all these laboratories in a similar to 100 nm thick mr-18010E film. Other materials, such as mr-17010E, were also tested. Good patterns were obtained and some limitations were identified. Reducing the pressure to 15 bars enables the printing of 50 nm structures without pulling them off. At higher pressures, some bending effects resulting in pattern deformation were observed. It was proven that a pressure of 1.5 bars is sufficient to imprint perfect 50 nm lines. The influence of the antiadhesive layer and mold design has been characterized by the demonstration of pulled off lines in some cases. Moreover, it has been shown that the scatterometry method is particularly useful for the characterization of 50 nm lines and that the residual layer thickness corresponds to the theoretical estimate as long as the lines are well defined. One process was demonstrated which combines high reproducibility with high throughput, achieving a cycle time of 2 min.

Nanomechanical resonators have been monolithically integrated on preprocessed complementary metal-oxide-semiconductor (CMOS) chips. Fabricated resonator systems have been designed to have resonance frequencies up to 1.5 MHz. The systems have been characterized in ambient air and vacuum conditions and display ultrasensitive mass detection in air. A mass sensitivity of 4 ag/Hz has been determined in air by placing a single glycerine drop, having a measured weight of 57 fg, at the apex of a cantilever and subsequently measuring a frequency shift of 14.8 kHz. CMOS integration enables electrostatic excitation, capacitive detection, and amplification of the resonance signal directly on the chip. (c) 2005 American Institute of Physics.

Utgivare: International Congress of Biological Physics, Plats: Gothenburg, Sweden, August 23-27 , Sidor: [invited lecture]

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Utgivare: MicroTas, Plats: Malmö, Sweden, September 26-29, Sidor: [invited lecture]

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Utgivare: European Muscle Conference, Plats: Elba, Italy, September 19-24, Sidor: [invited lecture]

Utgivare: NANO-8, Plats: Venice, Italy, June 28 - July 2, Sidor: [lecture]

Forskningsområdet Robusta inbyggda system bytte namn till Forskningsmiljö Material och tillverkning – Ytteknik 2011-01-01 Research area Robust Embedded Systems changed its name to Research area Materials and manufacturing - Surface technology 01-01-2011

A dry release method for fabrication of suspended nanostructures is presented. The technique has been combined with an anti-stiction treatment for fabrication of nanocantilever based nanoelectromechanical systems (NEMS). The process combines a dry release method, using a supporting layer of photoresist which is removed using oxygen ashing in a reactive ion etcher (RIE), with CHF3 plasma induced deposition of an fluorocarbon (FC) film acting as an antistiction coating. All in a single RIE sequence. The dry release process is contamination free and batch process compatible. Furthermore, the technique enables long time storage and transportation of produced devices without the risk of stiction. By combining the dry release method with a plasma deposited anti-stiction coating both fabrication induced stiction, which is mainly caused by capillary forces originating from the dehydration of meniscuses formed between suspended structures and the substrate during processing, as well as in-use stiction, occurring during mechanical operation of the system, are avoided. (C) 2004 Elsevier B.V. All rights reserved.

We have demonstrated the successful integration of a cantilever based mass detector with standard CMOS circuitry. The purpose of the circuitry is to facilitate the readout of the cantilever's deflection in order to measure resonant frequency shifts of the cantilever. The principle and design of the mass detector are presented showing that miniaturization of such cantilever based resonant devices leads to highly sensitive mass sensors, which have the potential to detect single molecules. The design of the readout circuitry used for the first electrical characterization of an integrated cantilever is described in detail. The integration of the cantilever is a post processing module and the full process sequence is discussed. One of the main challenges during the fabrication of the cantilevers is sticktion of the cantilever to the bottom substrate after underclothing. Two dry release techniques were used to solve the problem, namely freeze-drying and resist-assisted release. The fabrication results of cantilevers defined by laser and E-beam lithography are shown. Finally, an AFM based characterization setup is presented and the electrical characterization of a laser-defined cantilever fully integrated with CMOS circuitry is demonstrated. The electrical characterization of the device shows that the resonant behavior of the cantilever depends on the applied voltages, which corresponds to theory.

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