FORMING METHOD OF TUNGSTEN PLUG IN SEMICONDUCTOR DEVICE

摘要

PURPOSE: A forming method of a tungsten plug is to prevent the occurrence of a hole recess due to excessive etching on forming the tungsten plug, thereby satisfactorily embedding a contact hole and securing the stability and easiness of the subsequent manufacturing process. CONSTITUTION: A forming method of a tungsten plug comprises the steps of: providing a semiconductor substrate(21) on which an interlayer isolated film(22) having a contact hole(23) is formed; forming a tungsten layer on the interlayer isolated layer including the contact hole; forming a photoresist pattern on the tungsten layer at the upper part of the contact hole; etching the exposed part of the tungsten layer by the described depth with an etching process using the photoresist pattern as an etching mask; and removing the photoresist pattern, followed by forming a tungsten plug(25a) having a convex surface in the contact hole by etching the whole surface of previously etched tungsten layer.