| 摘要 |
PURPOSE:To realize a metal gate semiconductor device, which has excellent element characteristics and can be operated at high speed, by holding a conductive material such as titanium nitride between a high melting-point metallic layer and a polycrystalline silicon layer and forming three layers. CONSTITUTION:With a gate for an MISFETQ1, a polycrystalline silicon layer 4 is formed to a lower layer and a molybdenum layer 6 to an upper layer in thickness of approximately 2,000-3,000Angstrom respectively, and a thin titanium nitride layer in approximately 500Angstrom is held between the polycrystalline silicon layer 4 and the molybdenum layer 6 in a sandwich shape. Titanium nitride is a thermally and chemically extremely stable metal, and has not a poroperty of which it reacts with molybdenum and polycrystalline silicon. Consequently, boundary surfaces between the titanium nitride layer and the molybdenum layer and between the titanium nitride layer and the polycrystalline silicon layer are stabilized. Accordingly, the gate is stabilized electrically, and can be brought into ohmic- contact with an silicon substrate easily. |
