Apparatus and method for controlling temperature uniformity of substrates

An apparatus for controlled heating of a substrate in a chemical vapor deposition reaction chamber comprising:

• a carrier for holding at least one substrate in the reaction chamber, said carrier including a first zone and a second zone;
• means for heating said carrier;
• means for measuring a process temperature by measuring the temperature of at least one of said one or more substrates;
• means for providing a first zone signal representing a parameter related to temperature of said first zone of the carrier and a second zone signal representing a parameter related to temperature of said second zone of the carrier;
• and
• means for controlling said heating means so as to maintain said process temperature at a target temperature based at least in part upon comparison of said measured process temperature with a setpoint temperature and maintain temperature uniformity between said zones of said carrier based at least in part upon comparison of said zone signals.

A method of controlling the temperature of a substrate in a chemical vapor deposition apparatus comprising:

• providing a carrier for supporting said substrate in said chemical vapor deposition apparatus;
• heating said carrier and said substrate;
• measuring the temperature of said substrate;
• obtaining indications of a parameter related to carrier temperature from at least two zones of said carrier;
• comparing said parameter indications from said at least two zones to obtain a difference signal;
• and
• adjusting heat transfer to said zones responsive to said measured temperature and said difference signal so as to maintain said measured temperature at a setpoint and so as to maintain said difference signal at a preselected level.

A method of thermally processing one or more semiconductor wafers in a chemical vapor deposition apparatus comprising:

• providing a carrier supporting said one or more semiconductor wafers in said chemical vapor deposition apparatus;
• heating said one or more semiconductor wafers on said carrier to a target operating temperature;
• measuring the temperature of said semiconductor wafer using an emissivity compensated pyrometer;
• providing a difference signal related to the temperature difference between at least two zones on said carrier;
• and
• adjusting the temperature in one of the at least two zones of said carrier based at least in part upon said difference signal.