An electrical interconnection for a highly integrated semiconductor device includes a first insulation layer having at least a first recessed portion on a substrate. The first recessed portion is filled with metal to form a first metal pattern. A diffusion barrier layer including aluminum oxide of high light transmittance is provided on the first insulation layer and the first metal pattern for preventing metal from diffusing. An insulating interlayer including a second recessed portion for exposing an upper surface of the first metal pattern is provided on the diffusion barrier layer. The second recessed portion is filled with metal to form a second metal pattern. The electrical interconnection may be used with an image sensor. The metal may be copper. High light transmittance of the diffusion barrier layer ensures external light reaches the photodetector. The aluminum oxide of the diffusion barrier layer reduces parasitic capacitance of the electrical interconnections.