Semiconductor device and method for manufacturing the same

A method for manufacturing a semiconductor device, the method comprising:

• sequentially forming a gate oxide layer, a gate polysilicon layer, and a capping oxide layer on a semiconductor substrate;
• forming a photoresist pattern on the capping oxide layer;
• sequentially etching the capping oxide layer, the gate polysilicon layer, and the gate oxide layer using the photoresist pattern as an etch mask;
• implanting first ions into the semiconductor substrate using the photoresist pattern as an ion implantation mask;
• forming spacers on lateral sides of the etched capping oxide layer, the etched gate polysilicon layer, and the etched gate oxide layer;
• performing a thermal diffusion process on the semiconductor substrate into which the ions have been implanted to form source/drain regions;
• removing the capping oxide layer and portions of the spacers to expose the gate polysilicon layer;
• implanting second ions into the gate polysilicon layer;
• and
• depositing a first metal on the gate polysilicon layer, then forming a metal silicide from the metal and the gate polysilicon layer.