| 摘要 |
PURPOSE:To prevent the corrosion by a method wherein Ti is made to adhere to an Al wiring layer and etched, then it is heat treated after the removal of a cracked portion on the Ti film, and a Ti-Al alloy or TiAl3 film is formed while Ti which has not reacted yet is removed. CONSTITUTION:Al 3, Ti 4 are laminated on an Si substrate through an oxidized film 2. After adding a photoresist mask 8 and etching Ti, Al gradually in an etching liquid specified, a Ti layer 4a having the shape of a canopy is produced. Since this portion 4a will cause the abnormal growth of the portion when covering it with PSG later, it is etched in a liquid of ethylene diamine quatriacetic acid-NH4OH- H2O2-H2O series. After removing a mask 8 and heating treating it in H2+N2, a thin layer 5 of TiAl2 or Ti-Al alloy. Next Ti 4 which has not reacted yet is also etched in the same liquid. Then if PSG6 is piled, cracking of the PSG based on the hillock of the Al layer is not produced because of the layer 5, thus preventing the corrosion of Al 3. An opening is made in the PSG 6 to provide Al wiring. |
