Process chamber with rectangular temperature compensation ring

A method comprising the steps of:

• providing a vapor deposition chamber, the chamber having outer walls substantially transparent to radiation heat energy, said walls defining a gas inlet and a gas outlet, and said walls being sized to enclose a susceptor on which a wafer can be positioned between the inlet and the outlet;
• surrounding the susceptor with a ring having an outer generally rectangular perimeter and an inner circular opening sized to closely surround the susceptor, the ring being made of material which is much more heat absorbent than the chamber walls;
• radiating heat energy from a plurality of lamps in a bank sized to approximately conform to the projected shape of said perimeter so that most of the energy radiated directly into the chamber impinges on the area within said perimeter and is absorbed by the wafer, the susceptor, and the ring;
• providing a channel surrounding the circular opening in the ring, with the channel being connected to the ring;
• and
• positioning a temperature sensor in the channel to sense the temperature at a peripheral edge of the susceptor.

A method comprising the steps of:

• providing a vapor deposition chamber, the chamber having outer walls substantially transparent to radiation heat energy, said walls defining a gas inlet and a gas outlet, and said walls being sized to enclose a susceptor on which a wafer can be positioned between the inlet and the outlet;
• surrounding the susceptor with a ring having an outer generally rectangular perimeter and an inner circular opening sized to closely surround the susceptor, the ring being made of material which is much more heat absorbent than the chamber walls;
• radiating heat energy from a plurality of lamps in a bank sized to approximately conform to the projected shape of said perimeter so that most of the energy radiated directly into the chamber impinges on the area within said perimeter and is absorbed by the wafer, the susceptor, and the ring;
• and
• wherein the outer walls of the chamber include a pair of curved walls each having a convex exterior surface and a concave interior surface with the concave surfaces facing each other, and connector walls joining edges of said curved walls to create an interior space within which the wafer on the susceptor is positioned, the method further including the step of positioning the ring within an opening in a generally rectangular plate extending between and affixed to said connector walls.