Patent ID: 8084720

Claim:
A method for controlling the temperature of a substrate in a substrate processing system, the substrate processing system including a substrate holder for supporting said substrate and having a temperature sensor reporting a temperature at a region of said substrate and a heating element heating said region, said heating element being controlled by a temperature control system to control the temperature of said substrate using a PID control algorithm, the method comprising: selecting a plurality of set-point temperatures; selecting a plurality of PID parameter sets, each PID parameter set in said plurality of PID parameter sets including a proportional constant K P1 , an integral constant K I1 , and a derivative constant K D1 ; placing said substrate on said substrate holder; adjusting the temperature of said substrate to a set-point temperature provided in said plurality of set-point temperatures; processing said substrate for a period of time at said set-point temperature; changing the temperature of said region of said substrate from said set-point temperature to another set-point temperature provided in said plurality of set-point temperatures using a PID parameter set provided in said plurality of PID parameter sets for a ramp period of time and continuing to change the temperature of said region of said substrate from said set-point temperature to said another set-point temperature using each of the remaining PID parameter sets provided in said plurality of PID parameter sets in sequence for another ramp period of time, said another ramp period of time following said ramp period of time; and processing said substrate for another period of time at said another set-point temperature.