Abstract: A method and an apparatus for removing particulate contaminant are provided in order to ensure high purity during a tungsten suicide deposition process. The method for removing particulate contaminant in tungsten silicide deposition process using SiH4 as silicon source gas and NF3 as cleaning gas, includes purging a carrier gas line for an SiH4 silicon source gas to remove the contaminant in the chamber and carrier gas line when the carrier gas is supplied with the chamber, and the NF3 cleaning gas is supplied to the chamber to form plasma. After a plasma cleaning, the gas line flowing reaction gas responding to the SiH4 is purged to remove the contaminant in the chamber and the reaction gas line. As a result, any particulate contaminant is removed or remains at a minimum level that has no effect on the tungsten silicide deposition process.

Abstract: A clamp holds a semiconductor wafer during an Al reflow process. The clamp is made of a ceramic material, and thereby clamp surface roughening which damages semiconductor wafers and other damaging of the wafer caused by the deformation of the clamp are avoided. A sloped surface of the clamp pad can also reduce the damage on the wafer by reducing the contact area between the clamp pad and the wafer. In addition, the clamp has several features that can reduce heat dissipation from the wafer to outside during the Al reflow. Slots formed on the pad reduce the amount of heat conduction through the clamp, and the polished inner surface of the clamp cap reflects the heat radiated from the wafer back to the wafer.