FIELD OF INVENTION

The disclosure generally relates to apparatus for gas-phase processes. More particularly, exemplary embodiments of the present disclosure relate to radiation shields and apparatus including the shields that can be used in gas-phase reactors.

BACKGROUND OF THE DISCLOSURE

A gas-phase reactor often includes a reaction chamber, a susceptor to support one or more substrates within the reaction chamber, a gas distribution system, and an opening, such as gate valve, to allow loading and unloading of the substrates into or out of the reaction chamber and sealing of the reaction chamber during processing. During various gas-phase processes, the substrates can be heated to facilitate a reaction on a surface of the substrates—especially relative to the reaction on a surface of the reaction chamber—by heating the susceptor heater assembly. The substrates can be heated using a susceptor heater assembly that includes the susceptor and a heating device, which can be embedded in a portion of the susceptor. A reactor in which the substrates are heated, but in which the reaction chamber walls are not heated or are heated to a much lesser degree, is often referred to as a cold-wall reactor.

Cold-wall reactors can suffer from uneven heat distribution across a surface of a susceptor heater assembly and consequently across one or more substrates on the susceptor heater assembly. The uneven heat distribution can lead to temperature difference across a substrate during processing, which in turn, can lead to uneven film deposition, etch, clean, or the like processing on the substrate surfaces. At least part of the reason for the uneven heat distribution can arise from uneven heat flux from the susceptor heater assembly. Accordingly, improved apparatus and methods for providing heat across a surface of a susceptor heater assembly and across surfaces of one or more substrates on the susceptor heater assembly, while reducing uneven heat flux from the susceptor heater assembly and/or substrate, are desired.

SUMMARY OF THE DISCLOSURE

Various embodiments of the present disclosure provide an improved method and system for mitigating variances in heat flux from a susceptor heater assembly. By mitigating the variance of the heat flux, a variance of temperatures on a substrate residing on the susceptor heater assembly can be reduced, and therefore, process variation (e.g., deposition rate, etch rate, clean rate, or the like) across a substrate surface and/or across multiple substrate surfaces processed at one time can be reduced. As a result, a quality of substrate processing can be increased.

In accordance with at least one exemplary embodiment of the disclosure, a radiation shield for use in a reaction chamber of a reactor is provided. An exemplary radiation shield includes a plate comprising a first section and a second section, wherein the first section comprises an annular disc having an inner perimeter and an outer perimeter, and wherein the second section comprises a hollow frusto shape. The device further includes an attachment device for attaching the plate to a susceptor heater assembly within the reaction chamber. In accordance with various aspects of these embodiments, the inner diameter ranges from about 80 mm to about 90 mm, about 160 mm to about 170 mm, or about 240 mm to about 250 mm. In accordance with further aspects, the outer diameter ranges from about 300 mm to about 400 mm, about 450 mm to about 550, or about 500 to about 600. In accordance with further aspects, the inner perimeter does not contact the susceptor heater assembly when the radiation shield is placed in a position for processing substrates. In accordance with further aspects, the attachment device includes a slidable member to facilitate easy installation and/or removal of the radiation shield. The slidable member can include a structure, such as a block or a rivet to receive a fastener, such as a threaded fastener (e.g., a bolt or a screw) or other form of fastener. The slidable member can include one or more recesses to receive an alignment pin and/or a fastener, such as a threaded fastener. The slidable member can be attached to the plate at one end and to the susceptor heater assembly at the other end. In accordance with yet additional aspects, the radiation shield includes an alignment pin to align the attachment device relative to the susceptor heater assembly.

In accordance with another embodiment of the disclosure, a radiation includes a substantially planar, substantially annular plate. An inner diameter of the plate can range from about 80 mm to about 90 mm, about 160 mm to about 170 mm, or about 240 mm to about 250 mm. The outer diameter ranges from about 300 mm to about 330 mm, about 450 mm to about 550, or about 500 to about 600. In accordance with various aspects of this embodiment, the annular plate includes one or more protrusions extending from the outer diameter. The protrusions can be used to attach the annular plate to, for example, a flow control ring, as discussed in more detail below.

In accordance with further exemplary embodiments of the disclosure, the radiation shield is coupled to a portion of a susceptor heater assembly and/or a flow control ring that is coupled to the susceptor heater assembly. When the radiation shield is attached to the susceptor heater assembly and/or a flow control ring, the shield can travel with the susceptor heater assembly as the susceptor heater assembly moves within the reactor—e.g., from a load/unload position to a processing position—while maintaining a desired position relative to the susceptor. The combination of the radiation shield and the susceptor heater assembly and/or a flow control ring can be configured to provide desired heat flux patterns and/or gas flow patterns within the reactor.

In accordance with additional exemplary embodiments of the disclosure, an apparatus for supporting a substrate during a reaction process includes a susceptor heater assembly, including a body including an outer surface, a radiation shield, and optionally a flow control ring. The radiation shield can be attached to the outer surface and/or to the flow control ring that is attached to the outer surface. The radiation can be the same or similar to those described above and elsewhere in this disclosure. The apparatus can further comprise a cap overlying a top surface of the susceptor heater assembly. Additionally or alternatively, the apparatus can include one or more lift pins. The lift pins can be received within a space of the radiation shield that is defined by the inner perimeter of a plate and can be received within the susceptor heater assembly. The susceptor heater assembly can further include an inner region that includes a stem. In accordance with various aspects of these embodiments, the radiation shield does not contact the inner region or stem when the radiation shield is placed in a position for processing substrates. In accordance with further aspects, the inner perimeter does not contact the susceptor heater assembly when the radiation shield is placed in a position for processing substrates. In accordance with yet further aspects, the outer surface comprises a ledge. The radiation shield can be engaged with and/or rest on the ledge.

In accordance with at least one further exemplary embodiment of the disclosure, a method of using a radiation shield within a reaction chamber of a reactor includes the steps of providing a susceptor heater assembly having an outer surface comprising a ledge, attaching or otherwise engaging a radiation shield to the ledge, using a tool to measure a distance between an outer perimeter of the radiation shield and an interior surface of a reaction chamber, and adjusting placement of the radiation shield based on the measurement.

In accordance with another exemplary embodiment of the disclosure, a method of using a radiation shield within a reaction chamber of a reactor includes the steps of providing a susceptor heater assembly having an outer surface, providing a flow control ring coupled to the outer surface, and attaching or otherwise engaging a radiation shield to the flow control ring.

In accordance with yet additional exemplary embodiments of the disclosure, a method includes the steps of supporting a susceptor on a heater assembly, moving the susceptor heater assembly from a first position to a second position, processing a substrate, and moving the susceptor heater assembly from the second position to the first position.

Both the foregoing summary and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure or the claimed invention.

