| 摘要 |
PURPOSE:To prevent short of metal wiring in uppermost layer of multilayer wiring by forming a silica film layer on interlayer insulating film right under the uppermost wiring layer in advance of coating of ground metallic film for gold plating. CONSTITUTION:Lower layer wiring 1 is formed on an insulating film 5 and interlayer insulating film 2 covers whole surface of said film 5. Next, silica film solution is dropped in a wafer and a silica film 7 is formed by high-speed rotation, resulting in alleviation of steepness of the wiring 1 and structure of cut surface with a gentle slope. Then a through hole 8 is opened through a layer 7 and the film 2. Next, a ground metallic film for gold plating 3 covers the whole surface and a region except a gold plating wiring pattern part of the upper layer is covered with photoresist and then an exposed film 3 is plated with gold. After that, the photoresist is removed and the film 3 remained between th gold-plated pattern part and the gold-plated wiring pattern part is irradiated with Ar ion. At that time, a stepped part of the film 3 forms a cut surface having a gentle slope tereby enabling perfect removal of a ground metal. |
