摘要 |
A method for forming a contact plug formed of polysilicon and a method for manufacturing a semiconductor device using the same are provided. The contact plug is formed by etching back polysilicon which fills a contact hole and is deposited on an interlayer dielectric film using a gas mixture of SF6, CHF3, and CF4, thus planarizing the polysilicon. Also, the contact plug can be made protrude above the interlayer dielectric film by etching the entire surface of the exposed interlayer dielectric film around the polysilicon contact plug formed by etching back the polysilicon. According to the present invention, the degree of planarization of the polysilicon contact plug is improved by etching back the polysilicon using the gas mixture of SF6, CHF3, and CF4. Furthermore, it is possible to prevent contact failure due to the depression of the contact plug by etching the entire surface of the interlayer dielectric film thus causing the contact plug to protrude above the interlayer dielectric film, thereby increasing the plug's contact area and reducing the contact failure.
|