Support assembly for substrate backside discoloration control

A processing chamber for semiconductor processing, the processing chamber comprising:

• a chamber body having an interior volume;
• a support shaft assembly disposed in the interior volume, the support shaft assembly comprising:
• a support shaft system, the support shaft system comprising:
• a shaft;
• and
• a plurality of arms, each arm having a first end and a second end, the first end of each arm coupled to the shaft;
• a disc shaped heat plate supported by the support shaft system, the disc shaped heat plate having a top surface further comprising a plurality of grooves, wherein the disc shaped heat plate comprises:
• a first surface;
• a second surface;
• a third surface opposite the first surface and the second surface, the first surface vertically lower than the second surface;
• a plurality of holes, each hole of the plurality of holes has a top opening and a lower opening, the lower opening exposed to an interior volume of the processing chamber, the plurality of holes formed through the disc shaped heat plate, wherein a first group of the plurality of holes extends from the first surface to the third surface, and a second group of the plurality of holes extends from the second surface to the third surface;
• and
• a ring shaped susceptor having a plurality of fins, the plurality of fins disposed within the plurality of grooves of the disc shaped heat plate such that there is a gap between the disc shaped heat plate and the ring shaped susceptor, wherein the ring shaped susceptor has a plurality of susceptor holes formed therein, the plurality of susceptor holes align with the first group of the plurality of holes.

A method for processing a substrate in a processing chamber, the method comprising:

• flowing a process gas into the processing chamber, the processing chamber further comprising:
• a chamber body having an interior volume;
• a support shaft assembly disposed in the interior volume, the support shaft assembly comprising:
• a support shaft system comprising:
• a shaft;
• a plurality of arms, each arm having a first end and a second end, the first end of each arm coupled to the shaft, the second end of each arm having a pin receiving recess;
• and
• a plurality of removable support pins, each pin placed within a respective end of the pin receiving recess;
• a disc shaped heat plate supported by the support shaft system, the disc shaped heat plate having a top surface further comprising a plurality of grooves, wherein the disc shaped heat plate comprises:
• a first surface;
• a second surface;
• a third surface opposite the first surface and the second surface, the first surface vertically lower than the second surface;
• a plurality of holes, each hole of the plurality of holes has a top opening and a lower opening, the lower opening exposed to an interior volume of the processing chamber, the plurality of holes formed through the disc shaped heat plate, wherein a first group of the plurality of holes extends from the first surface to the third surface, and a second group of the plurality of holes extends from the second surface to the third surface;
• and
• a ring shaped susceptor supported by the plurality of removable support pins in the support shaft system such that there is a gap defined between the disc shaped heat plate and the ring shaped susceptor, wherein the ring shaped susceptor has a plurality of susceptor holes formed therein, the plurality of susceptor holes align with the first group of the plurality of holes;
• and
• flowing a purge gas out from beneath the substrate, through the gap formed between the disc shaped heat plate and the ring shaped susceptor.