Movable liner assembly for a deposition zone in a CVD reactor
View Patent ↗A chemical vapor deposition (CVD) reactor comprises a deposition zone, a substrate carrier and a liner assembly. The deposition zone is constructed so as to have a positive pressure reactant gases fixed showerhead introducing reactant gas supporting thin film CVD deposition. The substrate carrier movably supports a substrate and the liner assembly within the deposition zone and is heated so as to be subjected to a CVD process. The liner assembly partly encloses selected portions of the deposition zone, particularly portions of the substrate carrier and thereby enclose a hot zone surrounding a substrate to be processed so as to retain heat in that zone but allows gas flow radially outwardly toward walls of a surrounding cold-wall reactor with exhaust ports surrounding the deposition zone that exhaust spent reactant gases. The liner assembly is a sink for solid reaction byproducts while gaseous reaction byproducts are pumped out at the exhaust ports. The liner assembly is linearly movable away from the fixed showerhead.
1. A chemical vapor deposition (CVD) reactor, comprising:
a CVD deposition zone in a reaction chamber having a fixed showerhead assembly introducing CVD reactive gases under positive pressure into a deposition zone within the CVD deposition zone;
a heated and movable substrate carrier beneath the showerhead assembly in the reaction chamber constructed to support and transport at least one substrate within the reaction chamber so as to be subjected to a CVD process by CVD reactive gases; and
a liner assembly shrouding the deposition zone and including at least one partial enclosure around the deposition zone isolating the deposition zone and the substrate carrier, and surrounding the at least one substrate so as to retain heat in the deposition zone and allow gas to flow radially outwardly, wherein the at least one partial enclosure of the liner assembly includes:
a chamber lid liner and a showerhead liner in a shape of an outer tunnel enclosure of the deposition zone, the chamber lid liner including a plate and a pair of legs that are directly disposed on the substrate carrier at lateral sides of the plate, the plate extending from the legs along a length perpendicular to the legs and parallel to a length of the substrate carrier, the showerhead liner surrounded by the plate and overlaying a substrate processing location, and the outer tunnel enclosure adapted to minimize heat loss from regions receiving the CVD reactive gases, and
a deposition liner within and beneath the outer tunnel enclosure formed by the chamber lid liner and the showerhead liner, the deposition liner separate from the chamber lid liner and the showerhead liner, walls of the deposition liner being directly positioned on a susceptor held by the substrate carrier and surrounding all sides of the substrate, thereby protecting portions of the substrate carrier around the substrate, the outer tunnel enclosure allowing gas to flow radially outwardly, and the liner assembly mounted on the substrate carrier for motion with the substrate carrier.
2. A CVD reactor as in claim 1 , wherein at least a selected portion of the liner assembly is in thermal communication with a heat source so as to be maintained at an elevated temperature higher than the heated substrate, the heat source in a first environment.
3. A CVD reactor as in claim 1 , wherein material for at least a portion of the liner assembly is one of quartz, a ceramic, or graphite.
4. A CVD reactor as in claim 1 , wherein selected portions of the deposition zone include gas curtain regions surrounding outlets of the showerhead assembly.
5. A CVD reactor as in claim 1 , wherein selected portions of the substrate carrier include a gas exhaust region immediately surrounding a perimeter of each substrate.
6. A CVD reactor as in claim 1 , further comprising a lamp source of radiant energy directed through a radiant energy transmissive substrate carrier.
7. A CVD reactor as in claim 1 , wherein the substrate carrier is provided with rollers for linear motion.
8. A CVD reactor as in claim 7 , wherein the liner assembly is selectively removable from the reaction chamber upon said rollers.
9. A CVD reactor as in claim 1 , wherein the deposition liner is selectively removable from the reaction chamber along with the at least one substrate after the at least one substrate is subjected to the CVD process.
10. A CVD reactor as in claim 1 , wherein a location, a size, and a shape of the showerhead liner are configured to correspond to a gas inlet of the showerhead assembly.
11. A CVD reactor as in claim 1 , wherein the pair of legs of the chamber lid liner are directly disposed on the substrate carrier at locations outside where the walls of the deposition liner are directly positioned on the susceptor held by the substrate carrier.
12. A CVD reactor as in claim 1 , wherein the deposition liner is removable along with the substrate and the susceptor after each substrate is processed.