| 摘要 |
PURPOSE:To obtain a Schottky barrier diode having desired forward voltage and stable characteristics by silicifying a plural kind of metals in succession so that the depth of the interfaces among silicides and Si differs. CONSTITUTION:A window is bored to a thermal oxide film 12 on an Si substrate 10 and Pt 14 is applied, a PtSi layer 16 is formed through heat treatment and used as interface depth d1, and Pt 14 not reacted is removed through etching. A resist mask 18 is shaped and a window is bored at a position different from the layer 16 and Ti 20 is applied, and a TiSi layer 22 in interface depth of d2<d1 is formed through heat treatment. A third silicide layer 24 by a reaction with Ti 20 is shaped onto the PtSi layer 16 at that time, but the silicide layer 24 reaches up to the deepest section of the PtSi layer 16 and the change of barrier height can be prevented when the thickness of Ti 20 is set previously so that d1>d2 holds. A section not reacted in Ti 20 is removed through etching. Accordingly, Schottky barrier diodes at different forward voltage are respectively obtained between the layer 16 and the substrate 10, and the layer 22 and the substrate 10, and lastly Al wirings 26, 28 are attached, thus completing a semiconductor device. |
