Patent ID: 7049606

Claim:
An electron beam treatment apparatus that comprises: (a) a chamber comprising: (i) a cathode having an exposed surface capable of producing electrons; (ii) an anode having holes, the anode spaced apart from the cathode by a working distance that is greater than a mean free path of the electrons produced by the cathode; (iii) a wafer holder facing the anode; and (iv) a gas inlet to admit gas into the chamber at a gas introduction rate; (b) a pump to exhaust gas from the chamber at a gas exhaust rate, the gas introduction rate and the gas exhaust rate providing a gas pressure in the chamber; (c) a source of negative voltage whose output is applied to the cathode to provide a cathode voltage; and (d) a source of voltage whose output is applied to the anode; wherein values of the cathode voltage, gas pressure in the chamber, and working distance are such that there is no arcing between the cathode and anode at the working distance that is greater than the mean free path of the electrons from the cathode.