Patent ID: 7557328

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 first set-point temperature; selecting a second set-point temperature; selecting a first PID parameter set including a first proportional constant K P1 , a first integral constant K I1 and a first derivative constant K D1 ; selecting a second PID parameter set including a second proportional constant K P2 , a second integral constant K I2 and a second derivative constant K D2 ; placing said substrate on said substrate holder; adjusting the temperature of said substrate to said first set-point temperature; processing said substrate for a first period of time at said first set-point temperature; changing the temperature of said region of said substrate from said first set-point temperature to said second set-point temperature using said first PID parameter set for a first ramp period of time and continuing to change the temperature of said region of said substrate from said first set-point temperature to said second set-point temperature using said second PID parameter set for a second ramp period of time, said second ramp period of time following said first ramp period of time; and processing said substrate for a second period of time at said second set-point temperature.