Abstract: A method of tuning a microwave integrated circuit by trimming desired film-type circuit patterns included therein by a cold-pressure bonding technique is disclosed. More specifically, intercoupled circuit patterns are formed on a semi-insulating substrate with some circuit patterns having impedance characteristics of a desired nominal value. Each circuit pattern may comprise a plurality of conductive paths of malleable metal. Gaps are provided at appropriately chosen places in the conductive paths of predetermined circuit patterns. Selected ones of the gaps of the conductive paths are bridged to adjust the impedance characteristics of the associated predetermined circuit pattern by wiping with a probe the malleable metal of the conductive path at one end of the gap, across the gap to make contact with the malleable metal of the conductive path at the other end of the gap.