Abstract: An electronic device and method of making same wherein the device includes a substrate (e.g., a printed wiring board or semiconductor chip) having a circuit thereon, a first non-photosensitive layer (e.g., polyimide resin) positioned on the substrate and over the substrate's circuit, a second, photosensitive layer (e.g., epoxy resin) positioned on the first layer, and an electrically conductive layer positioned on the first, non-photosensitive layer and electrically coupled to the circuit through a hole in the first layer.

Abstract: An electronic device and method of making same wherein the device includes a substrate (e.g., a printed wiring board or semiconductor chip) having a circuit thereon, a first non-photosensitive layer (e.g., polyimide resin) positioned on the substrate and over the substrate's circuit, a second, photosensitive layer (e.g., epoxy resin) positioned on the first layer, and an electrically conductive layer positioned on the first, non-photosensitive layer and electrically coupled to the circuit through a hole in the first layer.

Abstract: To provide a bump structure for soldering by forming a solder layer on the chip surface while keeping the space between a package substrate and a semiconductor chip large. Form a bump structured in double layers at a chip 1 and connect it to an electrode 11 of a package substrate 10 by soldering. The lower layer 3a in the double-layer structure does not fuse in soldering, and a definite distance between the substrate and the chip can be maintained. The upper layer 3b actually fuses in soldering and operates to electrically connect the bump to the electrode on the package substrate. The melting point of the lower layer is preferably at least 20° C. higher than that of the upper layer.

Abstract: A metal bump structure constituted by forming a second metal layer on a first metal layer is used which meets the conditions that the first metal layer is not melted at the time of reflow heating for connecting a substrate with a semiconductor chip and the second metal layer is made of a metal producing no composition causing the reliability to deteriorate between the second metal layer and a solder portion formed on the substrate at the time of reflow heating for connecting the substrate with the semiconductor chip.