Processing system architecture with single load lock chamber
View Patent ↗A substrate processing system architecture includes an MOCVD reactor processing module coupled to a single three-level load lock chamber. The load lock has a heater at a first stationary location, a cold plate at a second secondary location, and a three-level transport system between the heater and cold plate. The transport system has two-position carrier transfer assembly with upper and lower stages, where the upper stage may move between an intermediate transfer level and an upper level proximate to the heater while the lower stage moves between a lower level proximate to the cold plate and the transfer level. The choreography of substrate transport between external loader, load lock and reactor allows substrates to be processed in the reactor while other substrates are post-process cooled, unloaded, and a new substrate loaded and preheated.
1. A wafer preheating and conditioning load lock chamber coupled to a processing module in a wafer processing system, the load lock chamber comprising:
a heater at a first stationary location within the load lock chamber;
a cold plate at a second stationary location within the load lock chamber in vertical relation to the heater; and
a three-level transport system located between the heater and cold plate and adapted to receive a wafer carrier at an intermediate transfer level and vertically move the carrier into a selected upper or lower level in proximity with one of the heater and cold plate, the three-level transport system having a two-position carrier transfer assembly with upper and lower stages, wherein in a lower position of the transfer assembly the upper stage is at the intermediate transfer level and the lower stage is at the lower level in proximity to the cold plate, and wherein in an upper position of the transfer assembly the lower stage is at the intermediate transfer level and the upper stage is at the upper level in proximity to the heater, wherein when the lower stage is at the intermediate transfer level it is at the same position as the upper stage when the upper stage is at the intermediate transfer level.
2. The load lock chamber as in claim 1 , wherein coupling between one or more external motors and internal rollers in the stages of the carrier transfer assembly is provided by an electromagnetic clutch.
3. The load lock chamber as in claim 1 , wherein internal rollers for each one of the upper and lower stages of the carrier transfer assembly are mechanically coupled, and the rollers of each stage are respectively driven by a single dedicated motor.
4. The load lock chamber as in claim 1 , wherein a cooled reflector plate is provided as thermal isolation in the carrier transfer assembly and located between the upper and lower stages thereof.
5. The load lock chamber as in claim 1 , wherein a surface of the cold plate has raised portions fitting within corresponding openings in an underside of a received wafer carrier when moved to the lower level proximate to the cold plate.
6. The load lock chamber as in claim 1 , wherein the load lock chamber includes a first door interfacing with an external environment and a second door interfacing with a processing module.