Method of tunnel containing structures

A tunnel containing structure which is capable of functioning as a magnetic memory device, a circuit device, such as a fluid circuit device, or the like and which is primarily constructed from photo-resist materials using photographic techniques. The tunnel containing structure is made by depositing a photo-resist coating on a substrate surface, partially exposing the resist coating to radiation having a proper spectral distribution and thereafter immediately depositing an additional coating on the first named coating so that the two become firmly bonded together. By exposing the second coating through a mask having selected spaced apart transparent areas and developing the latter coating in response to the exposure it is possible to produce channels in the second coating. A cover member is then bonded to the upper surface of the second coating through an additional layer of photo-resist material to form the tunnels. The structure can be used in the fabrication of magnetic storage devices, for example, by inserting driving wires in the tunnels and including conductive lines such as word straps on the substrate and the cover member.