| 摘要 |
PURPOSE: To feed an appropriate inert gas such as argon or a mixture of an inert gas and a reaction gas, such as argon and hydrogen to the back side of a wafer, treated in a CVD reaction chamber at the time of forming films of tungsten or another metal, metal nitride and metal silicide, so as to prevent adhesion of a substance onto the rear side of the wafer. CONSTITUTION: Each processing station has a gas dispersion head laid out above a platen. A vacuum chuck having a number of radial grooves and circular grooves provided on the upper surface of the platen holds a wafer at a predetermined position. A platen heater is provided on the lower side of the platen, and a rear side gas is heated within a bottom section of the platen and on the periphery thereof and is fed through the circular grooves into a peripheral region on the outside of the outermost groove of the vacuum chuck. In the peripheral region, the pressure of the rear side gas is maintained at a level higher than the pressure of a CVD reaction chamber, and the rear side gas flows out from the lower side of an edge portion of the wafer onto the platen and prevents a process gas from contacting the rear side of the wafer. |
