Method of producing Josephson tunnel barrier.

摘要

A method of producing a Josephson tunnel barrier is disclosed which comprises a first step of forming a first layer containing at least a lower layer superconducting film (12) on a substrate (11), a second step of selectively removing the surface portion of said first layer except for a predetermined portion to a preselected first depth and a third step of forming a first insulating film (14) at the removed portion of said first layer (12) in a thickness such that the surface of said first insulating film becomes substantially equal to the surface of said predetermined portion. This said second step can include a step of forming a mask (13) on said predetermined portion and then partially removing said lower layer superconducting film (12) to said first depth and said third step can include a step of depositing said first insulating film (14) by a film-forming method having high directivity on the surface of the left portion of said first layer (12) except said predetermined portion and on said mask and a step of removing said mask (13). The method can furthermore comprise a forth step of forming a tunnel barrier (15) on said predetermined portion of said lower layer superconducting film (12) and a fifth step of forming an upper layer superconducting film (16) on the surface of said first insulating film (14) and on said tunnel barrier (16).