Surface cleanness of substrate transported by XHV integrated process

The extreme high vacuum integrated process has been developed in order to t ransfer substrates among vacuum chambers without any contamination on the u ltra clean surface. The integrated process has five main line chambers, six sidetrack chambers, connector chambers and six vacuum instrument chambers for surface analyses and film preparation. Magnetic levitation transports a re installed into the line chambers because they have no sliding part to ge nerate dust particles as well as outgassing which may much damage the ultra clean substrate surfaces and environment. The levitation transports can tr ansfer a substrate among connected six chambers in the pressure change of l ess than 10(-10) Pa. Auger analysis shows that surface of a Cu coated steel substrate prepared in the film preparation chamber can be kept clean witho ut oxygen nor carbonate during the transportation from the film preparation chamber to the auger analysis chamber. (C) 2001 Elsevier Science B.V. All rights reserved.