Single wafer cleaning tool
The Raider platform of the company Semitool is an automatic single wafer cleaning tool which can handle 200 and 300mm wafers. It consists of 4 reactors, 2 reactors for each size and is configured for 2 main applications.:
Pre epitaxial clean
This process is used for surface preparation prior epitaxial growth of Si based materials. The goal of the process is to produce a hydrophobic water mark free surface state of the wafer. To achieve the objective the natural oxide is completely etched back with either liquid or gaseous HF.
Pre high-k deposition clean
After the complete removal of the native SiO2, it is possible to build up a new chemical SiO2 with ozone. This oxidation process is self-limited leading to an oxide thickness of about 1nm. By etching back the new grown SiO2 even ultrathin SiO2 layers with a thickness of 0,5nm can be produced which can be used as a substrate for high k deposition processes.