Hello,

  I am currently trying to simulate the vibrations of rectangular and circular
 thin film membranes, made of SiO2 (the thickness of the film is around 1um and
 the dimensions of the membranes are in the order of 1-1.5 milimeteres)

  Can anybody tell me the requiered formulas for calculation of the deflection
 of the membrane and the amount of stress in different parts of it?

  Thanks in advance,
  Behraad Bahreyni