Electrostatic clamp with lip seal for clamping substrates

An electrostatic clamping apparatus with lip seal for holding substrates in a vacuum processing chamber. The apparatus includes an electrostatic clamp, a sealing member surrounding the electrostatic clamp, and an edge ring surrounding the sealing member and holding the sealing member in place against the electrostatic clamp. The sealing member provides a seal between the electrostatic clamp and the substrate. This seal prevents the leakage of temperature control gas into the processing chamber and prevents process gas from reaching the electrostatic clamp and/or causing arcing in the chamber. In addition, by leaving a small gap between the sealing surface of the resilient sealing member and the edge of the electrostatic clamp, a helium distribution channel is created outside the electrostatic clamp top surface thus maximizing available contact area between the substrate and the clamp.