The governing pressure equations for Coulomb and J-R chucks were presented, and for the nominal parameters used, the J-R chuck was capable of producing significantly higher pressures for the same applied voltage in the contact (pin) regions. Due to the J-R chuck dependence on contact to initiate charge accumulation, the J-R chuck pressure is spatially nonuniform and restricted to the contacting regions. However, due to the Coulomb chuck having a spatially uniform pressure distribution, it could cause some reticle distortion between pins. A desirable attribute of a Coulomb chuck is that the pressure is not highly dependent on gap and therefore would not change appreciably due to the presence of a particle. If relatively tall pins are required to minimize particle effects, the force in a Coulomb chuck could be significantly reduced while the pressure in a J-R chuck would change a negligible amount. However, what still needs to be determined is how a J-R chuck will perform with a particle between a pin and the backside of the reticle. Additionally, in-plane distortion of the reticle surface was not included in this study.
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