Electrical contact structure and methods for forming the same

An electrical contact structure disposed on a thin film material layer on a substrate, comprising:

• a first barrier layer disposed on the substrate and covering a sidewall and a top surface of the thin film material layer, wherein the sidewall of the thin film material layer is at an end of the thin film material layer, and the first barrier layer has an upper portion and a lower portion, wherein the upper portion is directly above and in contact with the thin film material layer, and the lower portion is longer than the upper portion;
• a metal pattern disposed on the first barrier layer, wherein the first barrier layer has a protrusion part exceeding a sidewall of the metal pattern;
• and
• wherein the thin film material layer comprises a thin film resistance material or a thin film material of a magnetoresistance element, and the thin film resistance material comprises SiCr, NiCr or TaN, the magnetoresistance element comprises an anisotropic magnetoresistance element or a giant magnetoresistance element, and the thin film material of the magnetoresistance element comprises NiFe, CoFe, CoFeB, Cu, PtMn or IrMn.