Abstract: A topcoat material for applying on top of a photoresist material is disclosed. The topcoat material comprises at least one solvent and a polymer which has a dissolution rate of at least 3000 ?/second in aqueous alkaline developer. The polymer contains a hexafluoroalcohol monomer unit comprising one of the following two structures: wherein n is an integer. The topcoat material may be used in lithography processes, wherein the topcoat material is applied on a photoresist layer. The topcoat material is preferably insoluble in water, and is therefore particularly useful in immersion lithography techniques using water as the imaging medium.

Abstract: A sample of amniotic fluid containing cells may be taken out from the amniotic cavity by penetrating the wall of the amniotic cavity by means of a hollow needle (15) through which a volume of the amniotic fluid may be withdrawn. Outside the amniotic cavity the cells or part thereof are separated from the amniotic fluid which is immediately thereafter returned to the amniotic cavity. This means that it is possible to withdraw a relatively large amount of cells without considerably reducing the total volume of the amniotic fluid present in the amniotic cavity. Therefore, it is possible to take out a sample at an early stage of pregnancy period. The sample may, for example, be withdrawn by means of a sampling device comprising a one-way valve (16, 17) including a cell filter (17). The sampling device may further comprise a syringe with cylinder (10) and a piston (11) movably arranged therein.