A novel method to prepare a passive integrated low-pass filter is described. The filter device is based on the layer sequence of a metal-insulator-semiconductor (MIS) structure. In contrast to the standard MIS system, the metal electrode of the filter device is structured to gain a local variation of its lateral resistance. The lateral resistance forms, together with the capacitance of the insulating film, a ladder filter RC network with low-pass characteristic. Devices with filter characteristics of fourth order and maximal attenuations of -110 dB have been realized until now. The cut-off frequencies have been varied between about 25 muHz and 1 kHz. To prepare MIS filters with cut-off frequencies in the sub-millihertz region, it is necessary to deposit metal electrodes with very high sheet resistances (up to 10(15) Ohm/square). These sheet resistances Could be achieved by evaporation of very thin metal films with a granular, disordered morphology. Because of their granular structure, the thin films reveal a thermally activated conductivity. (C) 2003 Elsevier Ltd. All rights reserved.