AVS 61st International Symposium & Exhibition
    Vacuum Technology Monday Sessions
       Session VT-MoA

Paper VT-MoA1
A Capacitance Diaphragm Gauge with 10 mTorr Full Scale

Monday, November 10, 2014, 2:00 pm, Room 303

Session: Vacuum Measurement, Applications of UHV and Ultraclean Processes
Presenter: Martin Wüest, INFICON Ltd., Liechtenstein
Authors: M.P. Wüest, INFICON Ltd., Liechtenstein
P. Björkman, INFICON Ab, Finland
J. Bäckman, INFICON Ab, Finland
Correspondent: Click to Email
Etching of semiconductors chips is a complex process and there are critical process steps that tend to go to lower pressures. At lower pressures scattering at the residual gas is reduced which allows obtaining narrower and deeper vias, important for three-dimensional chip structures. Many etch process pressures today are around 1 Pa and use a 13.3 Pa full scale CDG in the second measurement decade where accuracy is already lower. We use ceramic technology to build pressure sensors that measure an elastic deformation of a diaphragm under the feeble pressure forces while being highly resistant to etch chemistries. Improvements to the manufacturing process now allow us to manufacture thinner, highly elastic, leak tight membranes. We now have developed a heated capacitance diaphragm gauge with 1.33 Pa (10 mTorr) full scale. The low full scale is achieved by the deflection of a thinner membrane and focus on noise reduction and not by electronic amplification. We will present pertinent performance parameters.