1) Can I get nanoimprint polymer solutions for other film thicknesses?

Apart from the standard nanoimprint polymer and resist solutions (see product listings) micro resist technology GmbH provides solutions customised for other film thicknesses as special designs on request. The maximum attainable film thicknesses for each series are the following.

Nanoimprint polymer Maximum attainable film thickness at 3000 rpm
mr-I 7000R 2 µm
mr-I 8000R 2 µm
SIPOL 4 µm
mr-I T85 25 µm
mr-I PMMA 35k 3 µm
mr-I 9000M 3 µm
mr-NIL 6000E 3 µm
mr-NIL210 2 µm
mr-UVCur21-Serie 1 µm
mr-UVCur21SF 1.6 µm (same as standard)
mr-XNIL26SF 4.7 µm

2) Does micro resist technology provide solvent thinners for the nanoimprint products?

In the case that you want to dilute a nanoimprint polymer solution for yourself in order to get thinner films after spin-coating, we could provide the following solvent systems.

Nanoimprint polymer Thinner
mr-I 7000R ma-T 1050
mr-I 8000R ma-T 1050
SIPOL ma-T 1050
mr-I T85 No thinner available
mr-I PMMA 35k ma-T 1045
mr-I 9000M ma-T 1045
mr-NIL 6000E ma-T 1045
mr-NIL210 ma-T 1078
mr-UVCur21-Serie ma-T 1070
mr-UVCur21SF -
mr-XNIL26 ma-T 1050
mr-XNIL26SF ma-T 1050

Please keep in mind that you have to filter the diluted solutions again in order to avoid particle contamination and to guarantee a high film quality. Syringe filters work for that purpose.

3) Do you have processing guidelines for each product series?

You will get the processing guidelines with the delivery of the product. Please contact the corresponding product manager, if you need further processing details before.

4) Do I have to apply a release agent on my imprint mould?

We strongly recommend to apply a release agent on the imprint mould in order to generate a high adhesion contrast between mould and substrate. The formed anti-sticking layer (ASL) prevents defects caused by sticking of the nanoimprint polymer on the mould. The most common release agent for silicon or silicon dioxide stamps is “F13-TCS” (1H,1H,2H,2H-perfluorooctyl-trichlorosilan, CAS number [78560-45-9],available from common specialty chemicals suppliers). 

The processing of F13-TCS for Si- and SiO2 moulds is described in: M. Beck et al., Improving Stamps for 10 nm Level Wafer Scale Nanoimprint Lithography, Microel. Eng. 61-62 (2002), 441-448; H. Schift et al., Controlled co-evaporation of silanes for nanoimprint stamps, Nanotechnology 16 (2005), S171-S175. 
Methods to deposit release agents on Nickel are described in S. Park, Anti-adhesive layers on nickel stamps for nanoimprint lithography, Microel. Eng. 73-74 (2004), 196-201; M. Keil, Process development and characterization of antisticking layers on nickel-based stamps designed for nanoimprint lithography, J. Vac. Sci. Technol. B22 (2004), 3283-3287.

5) What is the difference between the products mr NIL 6000E, mr-UVCur21, and mr-NIL210?

mr-NIL210 and mr-UVCur21 are UV-curable and liquid polymer systems for UV-based nanoimprint lithography. The spin-coated liquid films are cured by UV exposure at room temperature. There is no need for baking after the imprint step.

mr-NIL 6000E is a curing resist for thermal nanoimprint lithography, which forms a solid film after spin coating and prebake. It exhibits a low glass transition temperature (Tg) of about 40 °C. Thus, it can be imprinted at temperatures as low as 80 – 100 °C. But this epoxy-based material has to be cured by UV exposure and baking (comparable to the post exposure bake of chemically amplified resists). Otherwise there would be a reflow of the imprinted patterns on subsequent annealing. Curing can beneficially be done during imprinting in the imprint tool (if the machine has an exposure unit).

6) Do I have to use adhesion promoters on my substrates?

The use of adhesion promoters depends on the product series you want to use.

  • mr-I 7000E, mr-I 8000E, mr-I 7000R, mr-I 8000R: No adhesion promoter necessary on silicon, SiO2, aluminium, or chromium surfaces.
  • mr-I T85: No adhesion promoter necessary on silicon or SiO2 surfaces.
  • mr-I PMMA 35k: No adhesion promoter necessary on silicon, SiO2 or aluminium surfaces.
  • mr-I 9000M: No adhesion promoter necessary on silicon or SiO2 surfaces.
  • mr-NIL 6000E: No adhesion promoter necessary on silicon or SiO2 surfaces.
  • mr-NIL210, mr-UVCur21, and mr-XNIL26: For improving the polymer film adhesion to Si or SiO2 substrates it is advisable to apply an adhesion promoter on the substrate. We recommend the micro resist technologyproduct mr-APS1.Omnicoat (Microchem Corp., USA) works as an adhesion promoter, too. HMDS (Hexamethyl-disilazan) is not suitable.