METHOD FOR VAPOR DEPOSITING ALUMINUM THIN LAYER

PURPOSE:To form Al thin film easy in ultrasonic bonding and superior in adhesive property and corrosion resistance, by vapor depositing Al in gas phase by vacuum vapor depositing method firstly, successively by ion plating method, at forming Al layer on surface of metal, ceramic, organic material, etc. CONSTITUTION:An electrode 5 of metal, ceramic, organic material, e.g. IC1 and an Al electrode 3 on surface of a lead frame 2 are connected by a bonding wire 4. For forming the electrode 3 on the frame 2 surface, at first, Al is vapor deposited by >=1.5mum thickness at necessary part of said surface, by vacuum vapor depositing method. Successively, the second Al layer is formed thereon immediately by 0.5-2.0mum thickness by ion plating method, and the thickness of the first Al vacuum vapor deposited film is made to at least >=3 times as much as that of the second ion plated Al layer.