| 摘要 |
A method for fabricating a semiconductor device is provided to stably perform a silicide process by forming a T-shaped gate electrode so that the upper width of the gate electrode is broadened. A first buffer oxide layer is formed on a semiconductor substrate(1) having an underlying structure. The first buffer oxide layer is etched to expose the substrate. A gate oxide layer is formed on the exposed substrate. A first polysilicon layer(7) is formed to bury a portion from which the first buffer oxide layer is removed. The surface of the first polysilicon layer is planarized to expose the first buffer oxide layer. A second polysilicon layer(8) is formed on the first buffer oxide layer including the first polysilicon layer. The second polysilicon layer and the first buffer oxide layer are simultaneously etched to form a T-shaped gate electrode(10). A second buffer oxide layer(11), a nitride layer(12) and an oxide layer are sequentially formed on the resultant structure. The oxide layer, the nitride layer and the second buffer oxide layer are sequentially etched to form a gate spacer(13'). A metal silicide layer(14a,14b) is formed on the gate electrode and the substrate. The first buffer oxide layer can be used as a planarization stop layer in a process for planarizing the first polysilicon layer.
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