Heater for wafer processing and methods of operating and manufacturing the same

A heater for wafer processing comprising:

• a first heating unit comprising a substrate and a resistive heating element embedded in the substrate, the substrate having a top surface, a back surface, and a center area, the first heating unit generating a first temperature profile prior to operation of the heater;
• a shaft disposed proximate the back surface and the center area of the substrate, the shaft defining an inner space;
• and
• a second heating unit external to the substrate and disposed proximate the back surface of the substrate and within the inner space of the shaft,
• wherein prior to operation of the heater, the second heating unit is designed based on the first temperature profile of the first heating unit such that the second heating unit is designed to compensate for heat loss before operating the heater.

A method of operating a heater for wafer processing, the method comprising the steps of:

• providing a first heating unit comprising a substrate and a first resistive heating element embedded in the substrate, the substrate having a top surface, a back surface, and a center area, the first resistive heating element generating a first temperature profile on the top surface prior to operation of the heater;
• providing a second heating unit external to the substrate and proximate the back surface and the center area of the substrate, the second heating element generating a second temperature profile on the top surface of the substrate prior to operation of the heater;
• measuring a combined temperature profile on the top surface of the substrate prior to operation of the heater, the combined temperature profile defined by a combination of the first temperature profile and the second temperature profile;
• and
• adjusting the second temperature profile to achieve a predetermined combined temperature profile on the top surface prior to operation of the heater.

A method of manufacturing a heater for wafer processing, the method comprising the steps of:

• forming a first heating unit by hot pressing, the first heating unit defining a resistive heating element embedded in a substrate;
• forming a second heating unit by hot pressing, the second heating unit defining a resistive heating element embedded in a substrate;
• forming a shaft by sintering;
• and
• bonding the shaft and the second heating unit to a back surface of the first heating unit, the second heating unit being disposed within the shaft.