Apparatus and methods for managing the temperature of a substrate in a high vacuum processing system

Abstract

Apparatus and methods for improving the control of the temperature of a supported member, such as a substrate, in high vacuum processing systems, such as ion beam etch (IBE) systems. The apparatus includes thermoelectric devices that transfer heat from a support member supporting the supported member to a liquid-cooled heat exchange member to regulate the temperature of the support member. The method includes cooling the support member with thermoelectric devices that transfer the heat to the liquid-cooled heat exchange member.

1 . An apparatus for controlling the temperature of a supported member exposed to a treatment that heats the supported member, the apparatus comprising:
 a support member having a surface configured to support the supported member, said support member receiving heat from the supported member transferred to said surface;   a heat transfer member coupled with said support member, said heat transfer member including a channel configured for a flow of a temperature control liquid;   a supply passageway extending through said support and heat transfer members to communicate with a heat transfer gas space defined between said surface of said support member and the supported member; and   a plurality of thermoelectric devices disposed between said support and heat transfer members, each of said thermoelectric devices having a first side contacting said support member proximate to said surface and a second side contacting said heat transfer member proximate to said channel, and each of said thermoelectric devices transferring heat between said first and second sides to regulate the temperature of said support member.   
   
   
       2 . The apparatus of  claim 1  further comprising:
 at least one temperature sensor for detecting a temperature of said support member and generating electrical signals related to said detected temperature.   
   
   
       3 . The apparatus of  claim 2  further comprising:
 a temperature control unit coupled to said temperature sensor for receiving said electrical signals and coupled with said thermoelectric devices, said temperature control unit adapted to regulate power delivered to said thermoelectric devices based upon said electrical signals for controlling the temperature of said support member.   
   
   
       4 . The apparatus of  claim 3  wherein said thermoelectric devices are connected in series with the temperature control unit. 
   
   
       5 . The apparatus of  claim 3  wherein said thermoelectric devices are connected in parallel with the temperature control unit. 
   
   
       6 . The apparatus of  claim 1  wherein said thermoelectric devices are positioned between said surface of said support member and said channel in said heat transfer member. 
   
   
       7 . The apparatus of  claim 1  wherein said first side of each of said thermoelectric devices is a cold side and said second side of each of said thermoelectric devices is a hot side for transferring heat from said cold side to said hot side to cool the support member. 
   
   
       8 . The apparatus of  claim 1  wherein said support and heat transfer members bound a plurality of compartments, each of said compartments receiving a corresponding one of said thermoelectric devices. 
   
   
       9 . The apparatus of  claim 8  wherein said support member comprises a peripheral rim and a grid of ribs circumscribed by said peripheral rim for defining said compartments. 
   
   
       10 . The apparatus of  claim 8  wherein said compartments are arranged such that said thermoelectric devices are disposed in a plane substantially parallel with said surface of said support member. 
   
   
       11 . The apparatus of  claim 1  further comprising:
 a drain passageway communicating with said heat transfer gas space, said drain passageway permitting a flow of heat transfer gas from said supply passageway to said drain passageway.   
   
   
       12 . The apparatus of  claim 1  wherein said support member is separated from said heat transfer member by a gap that limits direct heat transfer between the first and heat transfer members. 
   
   
       13 . The apparatus of  claim 12  wherein said thermoelectric devices separate said first and heat transfer members to define the gap. 
   
   
       14 . A method for controlling the temperature of a supported member, the method comprising:
 exposing the supported member to an ion beam that heats the supported member;   transferring heat from the supported member with a backside gas in a heat transfer gas space between a backside of the supported member and a surface of a support member;   cooling the support member with a plurality of thermoelectric devices that transfer the heat from the support member to a heat exchange member; and   cooling the heat exchange member with a flow of a thermally conductive liquid.   
   
   
       15 . The method of  claim 14  further comprising:
 specifying a reference temperature to which the supported member is to be cooled while exposed to the ion beam;   measuring a temperature representative of the temperature of the supported member; and   regulating the operation of the thermoelectric devices to compensate for a difference between the reference and measured temperatures.   
   
   
       16 . The method of  claim 15  wherein measuring the temperature representative of the temperature of the supported member further comprises:
 measuring the temperature of the support member.   
   
   
       17 . The method of  claim 15  further comprising:
 increasing the power delivered to the supported member by the ion beam; and   reducing the representative temperature to compensate for the increased delivered power.   
   
   
       18 . The method of  claim 14  further comprising:
 heating the support member with the thermoelectric devices; and   venting a vacuum vessel housing the support member to atmospheric pressure.