Patent ID: 6901804

Claim:
A method of manufacturing a membrane sensor, comprising selecting into use a layer-structured preform comprising a first layer, a second layer made of conductive material, and an insulating layer between the first and second layers; removing material from the first layer by etching a cavity in the first layer, the cavity extending through the first layer as far as to the insulating layer; growing a membrane of conductive material on the insulating layer through the cavity formed in the first layer, the membrane joining to the walls of the cavity, forming a dense wall in the cavity; removing material from the second conductive layer by etching perforations in the second conductive layer, the perforations extending through the second conductive layer as far as to the insulating layer and being situated in a finished membrane sensor at the point of the cavity but on the side opposite to the insulating layer; and removing the insulating layer from the area between the perforations and the cavity.