METHOD FOR FABRICATING SEMICONDUCTOR DEVICE HAVING TUNGSTEN GATE ELECTRODE

摘要

A method for manufacturing a semiconductor device with a tungsten gate electrode is provided to improve thickness uniformity of the tungsten gate by using an alpha carbon layer as a hard mask. A poly gate including a gate oxide layer(11), a polysilicon layer and a nitride layer is formed on a substrate(10). A spacer(18a) is formed at both sidewalls of the poly gate. A sacrificial nitride layer(19) and an interlayer dielectric(20) are sequentially formed on the resultant structure. The sacrificial nitride layer is removed to expose the nitride layer by polishing. The exposed nitride layer is removed and the upper of the sacrificial nitride layer is simultaneously removed. Then, an insulating spacer(22) is formed at the exposed sides, and an insulating layer is filled. A tungsten gate is formed in the removing portion of the nitride layer.