| 摘要 |
A source/drain structural configuration suitable for metal-oxide semiconductor field-effect transistors is provided, having a wedge-shaped configuration with a thickness that increases in the direction from its end near to one the channel of the transistor toward the other end. The source/drain configuration includes a shallow junction advantageously formed to reduce sheet resistance and prevent the hot carrier punchthrough effect. The wedge-shaped source/drain configuration is fabricated by depositing a dielectric layer, which is flowable under thermal treatment, after the formation of a polysilicon gate electrode. After annealing, the dielectric layer is etched to form a wedge-shaped mask. The resulting mask has a thickness that decreases in the direction from its one end near the gate electrode toward the other end. The presence of the wedge-shaped shielding masks facilitates the formation of a pair of wedge-shaped source/drain regions on the substrate via implementation of an ion implantation procedure. The wedge-shaped mask also assists in achieving improved step coverage for the deposition of the pre-metal dielectric layer.
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