| 摘要 |
PROBLEM TO BE SOLVED: To increase the operating speed of a semiconductor device by reducing the wiring capacity of the device and to make a redundancy process easier, and then to stabilize the threshold voltage of a MOSFET by providing a wiring layer, consisting of a lower layer composed of polysilicon non-doped or having a resistivity of a specific value or higher and an upper layer composed of a metal silicide. SOLUTION: A first wiring layer, consisting of a lower layer composed of polysilicon 63 and 64 containing impurities at high concentrations and an upper layer composed of a metal silicide 11 having a first film thickness, is formed in the first area of a semiconductor substrate 1 with an insulating film in between. In addition, a second wiring layer consisting of a lower layer, composed of polysilicon 6 non-doped or having a resistivity of 10Ω.cm or higher and an upper layer composed of a metal silicide 10 having a second thickness thicker than the first film thickness is formed on the second area of the substrate 1 with an insulating film 5 in between. The silicide layer 10 formed on the non-doped polysilicon 6 grows to a thick flat layer, since no such impurity that suppresses silicification exists in the polysilicon 6. |
