US Patent 10021781 Thin circuit board having wall for solder material

A thin circuit board such as a flexure has a metal support layer forming a substrate, a base insulating layer provided on the metal support layer, a wiring layer being wiring traces provided on the base insulating layer, a cover insulating layer covering the wiring layer, internal terminals provided to the respective wiring traces and sequentially arranged side by side, each one internal terminal of said internal terminals used to be solder-bonded to a corresponding external terminal through solder material, and a wall provided for the solder material on at least any one of adjacent internal terminals of said internal terminals.