We present a method for integrating an isolated cell membrane patch into a semiconductor device. The semiconductor is nanostructured for probing native cell membranes for scanning probe microscopy in situ. Apertures were etched into suspended silicon-nitride layers on a silicon substrate using standard optical lithography as well as electron-beam lithography in combination with reactive ion etching. Apertures of 1 mu m diam were routinely fabricated and a reduction in size down to 50 nm was achieved. The stable integration of cell membranes was verified by confocal fluorescence microscopy in situ. (C) 2000 American Institute of Physics. [S0003-6951(00)01834-9].