Substrate having a pattern of an alloy of gold and a noble and a base metal with the pattern isolated by oxides of the noble and the base metals

Abstract

Abstract In a wired substrate, a conductive pattern is formed of an alloy of gold, a base matal, and a noble metal and is contiguous to an insulating layer of a mixture of oxides of the base and the noble metals. The alloy preferably includes the base and the noble metals to a total amount of 0.2 to 2 percent by weight. More preferably, the base metal is titanium, aluminium, or copper. The noble metal is palladium, ruthenium, rhodium, or nickel. The wired substrate is manufactured by forming a first layer of the base metal, a second layer of the noble metal, and a selectively formed gold layer successively on the substrate and by heat treating at least the first, the second, and the gold layers to convert the gold layer and those portions of the first and the second layers on which the gold layer is formed, to the conductive pattern and to concurrently convert other portions of the first and the second layers to the insulating layer. The first, the second, and the gold layers are preferably 0.025 to 0.4, 0.025 to 0.3, and 1 to 10 microns thick, respectively. When the base and the noble metals are titanium and palladium, respectively, the heat treatment is carried out in air at 850 DEG to 950 DEG for 5 to 10 minutes.

Inventors

• 👤 Akihiro Dohya

Bibliographic Details