| 摘要 |
PURPOSE:To make a tungsten film fine so as to improve the oxidation resistance of the film in the air by setting the partial pressure of the fluoride gas of a high- melting point metal within a prescribed range and making the gas to react with a material containing silicon within a prescribed temperature range, and then, controlling the substituent of silicon by the high-melting point metal. CONSTITUTION:The substituent of silicon by a high-melting point metal is controlled by setting the partial pressure of the fluoride gas of the metal which is used as a gaseous starting material within a range from 1X10<-6>Torr to 1X10<-1>Torr and making the material to react with a material which has a controlled surface impurity concentration and contains silicon. A polycrystalline silicon 103 is first deposited to a thickness of about 0.5mum on an insulating layer 102 formed on a semiconductor substrate 101 by a chemical vapor deposition method. Then polycrystalline silicon 103 is patterned as wiring by a lithographic method. The substrate 101 is heated to 250 deg.C and a silicon reducing reaction is performed for 10 minutes by controlling WF6 partial pressure to, for example, 0.5mTorr by using WF6 and Ar gas so as to make a tungsten film compacter by introducing silane gas into the reaction chamber after the polycrystalline silicon 103 is substituted by tungsten 104. Finally, an interlayer insulating film is formed on the tungsten film. |
