In-situ cryogenic measurement of low emissivity substrates

Abstract

A system for degassing a substrate provides a reduced infrared source in a degassing chamber. In some embodiments, the system includes: a degassing chamber having a microwave source and an infrared temperature sensor positioned in a bottom of the degassing chamber; at least one cuff having an annular shape, the at least one cuff configured to support or raise the substrate and formed of at least one first material, the at least one first material being opaque to microwaves and having an emissivity of 0.1 or less; and at least one actuator having a movable vertical shaft. Each of the at least one actuator is attached beneath one of the cuffs at an outer periphery of the cuffs. A portion of the movable vertical shaft exposed to microwaves from a microwave source in the degassing chamber is formed of at least one second material that is opaque to microwaves and has an emissivity of 0.1 or less.

Description

Technical Field

[0001] Embodiments of the present principles relate generally to semiconductor processing of semiconductor substrates. Background Art

[0002] During substrate processing, such as degassing, the temperature of the substrate being processed may be monitored. The temperature is then used to control the process, which may include heating the substrate to certain temperatures at certain points within the process. A proportional-integral-derivative or PID controller may be used to interpret the incoming substrate temperature in order to adjust one or more parameters of the process to a specific set point. If the temperature information of the substrate is incorrect, the PID controller will not be aware and will incorrectly set the parameters during the process, resulting in substandard performance of the substrate during downstream processing. The inventors have observed that during processing in a degas chamber, the PID controller will often establish incorrect set points for the degassing process of low emissivity substrate materials, thereby reducing process performance, and in turn, substrate performance during downstream processing.

[0003] Accordingly, the inventors provide an apparatus for ensuring correct in-situ temperature readings of low-emissivity substrates during processing. Summary of the invention

[0004] An apparatus for improving in-situ low-emissivity substrate temperature monitoring is provided herein.

[0005] In some embodiments, a system for degassing a substrate may include: a degassing chamber having a microwave source and an infrared temperature sensor positioned in a bottom of the degassing chamber; at least one hoop configured to support or elevate a substrate, wherein the at least one hoop has an annular shape and is formed of at least one first material that is opaque to microwaves and has an emissivity of 0.1 or less; and at least one actuator having a movable vertical axis, wherein each of the at least one actuator is attached below one of the at least one hoop at an outer periphery of the at least one hoop, wherein at least a portion of the movable vertical axis exposed to microwaves from the microwave source in the degassing chamber is formed of at least one second material that is opaque to microwaves and has an emissivity of 0.1 or less.

[0006] In some embodiments, the system may further include: wherein the at least one first material comprises a first coating applied to the at least one hoop, the first coating being opaque to microwaves and having an emissivity of 0.1 or less, wherein the first coating is a silver-based material or an aluminum-based material on a core material of stainless steel, wherein the at least one second material comprises a second coating applied to at least the portion of the movable vertical shaft member exposed to microwaves from the microwave source in the degassing chamber, and wherein the second coating is opaque to microwaves and having an emissivity of 0.1 or less, wherein the second coating is a silver-based material or an aluminum-based material on a core material of stainless steel, and wherein the silver-based material or the aluminum-based material has an emissivity of 0.1 or less, wherein the movable a movable vertical axis comprising an upper portion of a third material and a lower portion of a fourth material, the third material being opaque to microwaves and having an emissivity of 0.1 or less, wherein the movable vertical axis is formed of an aluminum-based material, the aluminum-based material being opaque to microwaves and having an emissivity of 0.1 or less, a proportional-integral-derivative (PID) controller, the PID controller communicating with the infrared temperature sensor and the microwave source, wherein the PID controller is configured to control a processing temperature of the substrate based on readings from the infrared temperature sensor and adjustments of the microwave source, wherein one of the at least one hoop is configured to support the substrate during processing in the degas chamber, and / or wherein one of the at least one hoop is configured to elevate the substrate before and after processing in the degas chamber.

[0007] In some embodiments, a component for a degassing chamber may include: a movable vertical shaft configured to be installed in the degassing chamber, wherein the movable vertical shaft has a bottom end configured to be attached to an actuator and a top end configured to be attached to a hoop, the hoop being configured to support or elevate a substrate, wherein when installed in the degassing chamber, an upper portion of the movable vertical shaft is exposed to the internal environment of the degassing chamber, and wherein the movable vertical shaft is formed of at least one material that is opaque to microwaves and has an emissivity of 0.1 or less.

[0008] In some embodiments, the assembly may further include: wherein the at least one material includes a coating applied to at least the upper portion of the movable vertical shaft, at least the upper portion of the movable vertical shaft is exposed to the internal environment of the degassing chamber when the movable vertical shaft is installed in the degassing chamber, and wherein the coating is opaque to microwaves and has an emissivity of 0.1 or less; wherein the coating is a silver-based material or an aluminum-based material on a core material of stainless steel, and wherein the silver-based material or the aluminum-based material has an emissivity of 0.1 or less; wherein the movable vertical shaft includes the upper portion and the lower portion, wherein the upper portion is removable from the lower portion, and wherein the upper portion is formed of a material that is opaque to microwaves and has an emissivity of 0.1 or less, and the lower portion is formed of stainless steel; wherein the upper portion and the lower portion are pressed together, welded together, threaded together, or bolted together; and / or wherein the movable vertical shaft is formed of an aluminum-based material that is opaque to microwaves and has an emissivity of 0.1 or less.

[0009] In some embodiments, a component for a degassing chamber may include: a hoop configured to support or elevate a substrate in the degassing chamber, wherein the hoop has an annular shape having an area configured to be attached to a movable shaft member, the movable shaft member being connected to an actuator, wherein the hoop is formed of at least one material that is opaque to microwaves and has an emissivity of 0.1 or less.

[0010] In some embodiments, the assembly may further include: wherein the at least one material includes a coating applied to an outer surface of the hoop, wherein the coating is opaque to microwaves and has an emissivity of 0.1 or less, wherein the coating is a silver-based material or an aluminum-based material on a core material of stainless steel, and / or wherein the hoop is configured to support the substrate during processing in the degassing chamber, or is configured to elevate the substrate before and after processing in the degassing chamber.

[0011] Other and further embodiments are disclosed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Embodiments of the present principles, briefly summarized above and discussed in more detail below, may be understood by referring to the illustrative embodiments of the present principles depicted in the accompanying drawings. However, the accompanying drawings illustrate only typical embodiments of the present principles and are therefore not to be considered limiting of scope, as the present principles may admit to other equally effective embodiments.

[0013] Figure 1 A graph depicting a first run of substrates in an unprocessed degas chamber, according to some embodiments of the present principles.

[0014] Figure 2 A diagram depicting a second run of substrates in a processed degas chamber, according to some embodiments of the present principles.

[0015] Figure 3 Materials with high emissivity that are transparent to or absorb microwaves, in accordance with some embodiments of the present principles are depicted.

[0016] Figure 4 Depicted are materials with low emissivity that are opaque to microwaves, in accordance with some embodiments of the present principles.

[0017] Figure 5 Depicted is a degassing chamber with a high emissivity chamber assembly, according to some embodiments of the present principles.

[0018] Figure 6 Depicted is a degas chamber having a low-emissivity chamber assembly including a low-emissivity collar and a low-emissivity shaft material for an actuator assembly of the degas chamber, according to some embodiments of the present principles.

[0019] Figure 7 Depicted is a degas chamber having a low-emissivity chamber assembly including a low-emissivity collar and a low-emissivity two-piece shaft for an actuator assembly of the degas chamber, according to some embodiments of the present principles.

[0020] Figure 8 Depicted is a low emissivity shaft for an actuator assembly of a degas chamber, according to some embodiments of the present principles.

[0021] Fig. 9 Depicted is a low-emissivity collar of a degassing chamber, according to some embodiments of the present principles.

[0022] To facilitate understanding, the same reference numerals are used where possible to indicate the same elements common to the drawings. The drawings are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be beneficially incorporated into other embodiments without further description. DETAILED DESCRIPTION

[0023] The method and apparatus provide a chamber environment that facilitates determination of in-situ substrate temperature of substrate materials having low emissivity at low temperatures (less than 200 degrees Celsius). Infrared (IR) temperature sensors installed in chambers such as degas chambers often "misread" substrate low emissivity materials such as silicon. Erroneous readings can result in improper control of the degas process by a PID controller. By reducing the emissivity of components within the degas chamber, more accurate substrate readings are possible, significantly improving quality control of the process and producing higher performance substrates in downstream processing.

[0024] In industries that use high temperatures (e.g., 500 degrees Celsius to 700 degrees Celsius, etc.), degassing chambers have been used for drying and degassing substrates. At high temperatures, substrate materials (such as, for example, silicon) exhibit higher emissivity characteristics. However, with the introduction of polymer materials as part of semiconductor manufacturing, high temperatures can deform and damage polymer materials. When the degassing chamber is operated at low temperatures (less than 200 degrees Celsius), the emissivity of the substrate material changes, and in the case of silicon, it becomes a low emissivity substrate material of 0.1 or less. The processing of polymer materials brings about low temperature degassing, which presents the problem of reading substrate materials with low emissivity characteristics at low temperatures. The inventors have observed that substrates are not completely dried and / or degassed at low temperatures. Increasing the degassing time for each substrate is unacceptable because the throughput of the degassing process will be significantly reduced. Therefore, the inventors have identified the root cause and provided a solution to achieve accurate IR temperature readings, and subsequently produced degassing processes with higher quality and yield. The method and apparatus disclosed herein provide a solution for low temperature IR readings of low emissivity materials and can be used in other types of chambers besides degassing chambers.

[0025] In an example using, but not limited to, a degassing chamber, the inventors have discovered that microwaves used to dry and degas substrates by heating the substrates will also heat high emissivity chamber components, which will then emit IR, effectively overpowering the IR temperature sensor readings of the substrates. The IR temperature sensor begins reporting the temperature of the heated chamber components to the process controller, rather than the substrate temperature. The process controller then incorrectly changes the amount of microwave power required to reach the temperature set point. The inventors have discovered that as subsequent substrates are processed in the chamber, less heating of the substrate will occur because the degassing chamber retains the heat in the high emissivity components. The incorrect readings can lead to increased moisture / gas retention in the substrate, which causes delamination and other defects during subsequent substrate processing for plasma vapor deposition (PVD) metal films. The inventors have discovered that by using chamber components that do not readily absorb microwave energy and transmit microwave energy via IR radiation, the IR sensor readings can be substantially improved.

[0026] The inventors have discovered that by creating a chamber with a low emissivity component of 0.1 or less at low temperature, low emissivity substrate materials can be accurately monitored. In the case of a degassing chamber, the inventors have also discovered that accurate reporting of the in-situ temperature of the substrate can be substantially improved by specifically reducing the emissivity of the lifting and supporting hoop assembly and the actuator shaft assembly that controls the movement of the hoop. The inventors have further discovered that low emissivity can be achieved by replacing existing high emissivity materials used to form components with low emissivity materials. However, in some cases, low emissivity materials may not have the structural rigidity necessary to perform components made of higher emissivity materials. The inventors have discovered that a low emissivity coating can be used on the high emissivity material of the component to form a component with high rigidity and also low emissivity. The thickness of the low emissivity coating or plating is determined by the penetration depth or skin effect of microwaves. The thickness is selected to be greater than the penetration depth or skin effect based on the microwave frequency and the coating material so that the microwave energy is not absorbed and radiated from the component in IR form (the coating or plating is thick enough to reflect or absorb the microwave energy before the energy can be transmitted and absorbed by the underlying material / materials).

[0027] In the example of a degassing chamber, an IR temperature sensor is typically mounted on the bottom of the degassing cavity and used as the primary or sole substrate temperature monitoring sensor. The degassing chamber contains at least one hoop assembly and an actuator shaft assembly for supporting and conveying the substrate. The inventors have found that if the hoop assembly and the actuator shaft assembly are made of low emissivity materials, temperature reporting errors will be substantially reduced. When using low emissivity materials, the substrate is heated but the hoop assembly and the actuator shaft assembly generate negligible IR energy from microwaves, thereby reducing the IR noise obtained by the IR temperature sensor. However, the lifting hoop assembly needs to be structurally rigid to provide support without vibration, and can be coated or plated with a low emissivity material (such as silver or aluminum, etc.) on a high emissivity material (such as stainless steel, etc.). The actuator shaft assembly can also be coated or plated with a low emissivity material on a high emissivity material (such as stainless steel, etc.). The actuator shaft assembly can also be formed by an actuator shaft extension of a low emissivity material (such as aluminum and / or ceramic, etc.). The actuator shaft extension may include only the portion of the actuator shaft that is exposed to the chamber processing environment, thereby allowing the remainder to be made of stronger and higher emissivity materials, such as stainless steel, etc. The inventors have discovered that silver or aluminum plating on stainless steel provides a low emissivity component for low temperature, low emissivity material substrate processing. The inventors have also discovered that ceramic, polyetheretherketone (PEEK) materials, and / or cross-linked polystyrene microwave stable materials can be used to form chamber components and / or as a coating for stainless steel components and other structural rigid materials. Rhodium can also be applied to the silver coating / plating to prevent the silver coating / plating from tarnishing.

[0028] Figure 1100A and 100B are first graphs 102 versus temperature 104 and second graphs 100B of time 122 versus microwave power 124 for a first run of substrates in a degassing chamber where the assembly is not processed for reduced infrared transmission. The inventors have found that for the first few substrates, the actual substrate temperature 114 reaches 110 the desired substrate temperature, allowing a high quality degassing operation to be performed. As additional substrates are processed, the idle temperature 108 read by the IR temperature sensor increases, resulting in a reduced difference 112 between the idle temperature 108 and the desired substrate temperature 106. As depicted in the second graph 100B, when the idle temperature 108 is low, the microwave power 130 initially applied to the initial substrate is high (as indicated by the microwave power curve 128), meeting the desired power level 126 and raising the actual substrate temperature 114 to the desired substrate temperature 106. When the idle temperature 108 is high (reduced difference 112), the subsequently applied microwave power 132 is very low (as indicated by the microwave power curve 128), resulting in poor substrate degassing because the low applied power is insufficient to bring the substrate to the desired substrate temperature 106 (the actual substrate temperature 114 for substrates later in a run is much lower than the initial substrate).

[0029] The inventors have discovered that the PID controller uses the idle temperature as the preheat substrate state and determines the microwave power required to heat the substrate from the idle temperature 108 to the desired substrate temperature 106 (PID set point), resulting in insufficient heating of the substrate (the substrate is actually at a much lower temperature, see Figure 1 The inventors further discovered that during processing, microwaves are heating components (e.g., supports, actuators, etc.) in the degas chamber along with the substrate, causing the chamber components to radiate IR that masks the IR that the IR temperature sensor is attempting to read from the substrate. Although at the initial start of a run, the chamber components contribute little IR noise to the IR temperature sensor reading, after processing a few substrates, the IR noise from the chamber components increases to a level that nearly masks the IR emitted by the substrate. The problem is further exacerbated by the low emissivity of the substrate material (e.g., 0.1 emissivity silicon) at the low temperatures (e.g., less than 200 degrees Celsius) that the IR sensor reads.

[0030] The inventors determined that the hoops used to transport and support the substrates, along with the shafts exposed to the chamber environment, contribute the majority of the emitted IR within the degas chamber components. The inventors found that by reducing the emissivity of certain chamber components to an emissivity of 0.1 or less, the idle temperature within the degas chamber was substantially reduced, resulting in substrates being heated to a desired temperature and higher quality processing. Figure 22 is a third graph 200A of time 102 versus temperature 104 and a fourth graph 200B of time 122 versus microwave power 124 for a second run of substrates in a degas chamber in which certain chamber components were treated to reduce infrared emissions. The inventors discovered that using the ferrules and shafts treated to reduce IR emissions, the idle temperature 108A was substantially reduced, allowing the PID controller to correctly determine the microwave power required to heat the substrate to the desired substrate temperature 106 (the difference between the idle temperature 108A and the non-idle temperature is exaggerated in the third graph 200A to be more easily discerned and understood). The inventors discovered that the actual substrate temperature 114A of the second run of substrates substantially reached 112A the desired substrate temperature 106 because the idle temperature 108A was reduced to an insignificant level, allowing a high quality degas operation to be performed, increasing the degas process throughput (the difference between the actual substrate temperature 114A and the desired substrate temperature 106 is exaggerated in the third graph 200A to be more easily discerned and understood). Using an IR temperature sensor with the ability to correctly read IR from the low emissivity material of the substrate, the PID controller is able to correctly apply power to the microwave source, in order to heat the substrate to the desired substrate temperature 106. After processing, the second subsequently applied microwave power 132A is substantially the same as the initially applied microwave power 130, resulting in proper heating of the substrate throughout the second pass of the substrate.

[0031] In general, microwaves can be transmitted (through the material), reflected (from the surface of the material), and / or absorbed (which can cause heating of the material). Although metal materials reflect a substantial portion of microwaves, microwaves can also pass through metal materials if the metal material is thin enough. The thickness and type of material affects the amount of microwaves transmitted, reflected, and absorbed. Figure 3 , a first view 300A depicts a first material 302A that transmits and absorbs microwaves 304. As the microwaves 304 pass through the first material 302A, some of the microwave energy is absorbed and the first material 302A is heated, resulting in IR noise 306 being emitted from an exposed surface 310 of the first material 302A. Figure 3 In the second view 300B of , a second material 302B that is opaque to microwaves and absorbs microwaves 304 is depicted. When the microwaves 304 are absorbed into the second material 302B, the microwaves heat the second material 302B, resulting in IR noise 306 being emitted from an exposed surface 312 of the second material 302B. The inventors have discovered that both a first material 302A that is microwave transparent and a second material 302B that absorbs microwaves are problematic because IR noise 306 is emitted from both types of materials and results in incorrect IR temperature sensor readings. The inventors have discovered that a material that is opaque to microwaves and has a low emissivity of 0.1 or less provides the best material for reducing the emitted IR noise. Figure 4, the first view 400A depicts a third material 402A that is opaque to microwaves 304 (microwaves 304 are mostly reflected 304A by the third material 402A) and has a low emissivity (emissivity of 0.1 or less) of IR noise 306. Types of materials that possess such properties may be, but are not limited to, silver, aluminum, ceramic, polyetheretherketone (PEEK), and / or cross-linked polystyrene microwave stable materials, etc. The lower the emissivity, the less IR noise is emitted, and the more accurately the IR temperature sensor reads the substrate temperature.

[0032] Some materials, such as PEEK, silver, and polystyrene, although good at absorbing microwaves while emitting low IR noise levels, are not suitable for use as structural components due to the softness of the materials. However, the inventors have discovered that the materials can still be used as coatings for use as structural component materials. Figure 4 , a second view 400B depicts a structural material 402B, such as, but not limited to, a stainless steel material coated with a microwave opaque material 404 having a low emissivity of 0.1 or less. By combining multiple types of materials, structural rigidity is maintained while reducing IR noise emissions, allowing for more accurate IR temperature sensor readings. The thickness 406 of the microwave opaque material 404 or coating should be sufficient to prevent any skin depth effects from allowing microwaves to be transmitted through the material (different microwave wavelengths used in a given chamber may require different thicknesses, etc.). In some embodiments, the coating may be applied via a coating process such as electroplating (e.g., electroplating silver on stainless steel, etc.). In some embodiments, an optional rhodium layer 408 may be applied to the silver coating to prevent tarnishing on the outer surface of the silver coating.

[0033] exist Figure 5 500, a degassing chamber 502 with a high emissivity chamber assembly is depicted. The degassing chamber 502 has a microwave source 504 having a guide opening 506 into a processing volume 550 of the degassing chamber 502. In some embodiments, the degassing chamber 502 may have a lifting hoop 522 with a lifting rod 524, and the lifting hoop 522 is attached to a first actuator 530 via a first actuator shaft 526. The lifting hoop 522 lifts and transports the substrate 508 in and out of the degassing chamber 502. The first actuator shaft 526 passes through a first bellows 528, which bends when the first actuator shaft 526 moves 532 to prevent the processing volume 550 from being exposed to the external environment. The first actuator shaft 526 moves 532 in response to the movement 534 of the first actuator 530. In some embodiments, the first actuator 530 and the first actuator shaft 526 may also rotate 566 about a central axis 564 of the first actuator shaft 526. In some embodiments, the degas chamber 502 may have a substrate support collar 510 attached to the second actuator 516 via a second actuator shaft 512.

[0034] The substrate support hoop 510 supports the substrate 508 during degassing of the substrate 508. The second actuator shaft 512 passes through a second bellows 514, which bends when the second actuator shaft 512 moves 518 to prevent the processing space 550 from being exposed to the external environment. The second actuator shaft 512 moves 518 in response to the movement 520 of the second actuator 516. In some embodiments, the second actuator 516 and the second actuator shaft 512 can also rotate 562 around the central axis 560 of the second actuator shaft 512. The IR temperature sensor 536 is positioned in the bottom 570 of the degassing chamber 502. The IR temperature sensor 536 reads the temperature of the substrate 508 based on the radiation IR emitted from the substrate 508. A controller 538 having a central processing unit (CPU) 540 , memory 542 , and supporting circuits 544 may be configured to operate as a PID controller that interfaces with the IR temperature sensor 536 and the microwave source 504 to facilitate regulating the temperature of the substrate 508 during processing in the degas chamber 502 .

[0035] The inventors have discovered that for low emissivity substrate materials, having an emissivity of approximately 0.1 or less at low temperatures (approximately 200 degrees Celsius or less), it is difficult for the IR temperature sensor 536 to determine the actual temperature of the substrate 508 because the IR noise emitted by other chamber components within the processing volume 550 is stronger than the IR emitted from the substrate 508. Initial substrates in a round of substrates may be processed correctly, but subsequent substrates in the round do not reach a high enough temperature to be acceptably degassed because components within the degas chamber 502 absorb energy from the microwaves over time and emit greater amounts of IR noise, thereby increasing the idle temperature of the degas chamber 502 when no substrates are in the chamber. The high idle temperature causes subsequent substrates to degas at low temperatures, resulting in poor quality degassing and performance issues in downstream processing (e.g., metal film delamination).

[0036] Since the IR temperature sensor 536 is positioned at the bottom 570 of the degas chamber 502, the inventors discovered that the first actuator shaft 526, the lift hoop 522, the second actuator shaft 512, and the substrate support hoop 510 were emitting a substantial amount of unwanted IR noise. The stainless steel material used to form the above chamber components absorbs microwaves during the degas process and has a high emissivity of over 0.2, which tends to emit IR noise (read by the IR temperature sensor 536) inside the processing volume 550, resulting in inaccurate substrate temperature readings. In order to reduce the unwanted IR noise inside the processing volume 550, the first actuator shaft 526 was replaced with a first low emissivity actuator shaft 626, the second actuator shaft 512 was replaced with a second low emissivity actuator shaft 612, the lift hoop 522 was replaced with a low emissivity lift hoop 622, and the substrate support hoop 510 was replaced with a low emissivity substrate support hoop 610, as shown in FIG. Figure 6600 is depicted in FIG.

[0037] When the chamber components are replaced with low emissivity (emissivity of 0.1 or less) components, the idle temperature of the degassing chamber 502 drops to negligible levels, allowing the IR temperature sensor 536 to read the temperature of the substrate 508 with high accuracy. The accurate temperature readings reported by the IR temperature sensor 536 to the PID controller of the controller 538 allow the PID controller to correctly control the microwave power required by the microwave source 504, which in turn heats the substrate 508 to the desired processing temperature, increasing the quality and yield of the degassing process. In some embodiments, the first low emissivity actuator shaft 626 and the second low emissivity actuator shaft 612 are formed of a low emissivity material (e.g., aluminum, etc.). The aluminum material is opaque to microwaves and has an emissivity of less than 0.1, while its structural rigidity is sufficient to meet the structural requirements of a functional actuator shaft.

[0038] In some embodiments, the first low-emissivity actuator shaft 626 and the second low-emissivity actuator shaft 612 may be a stainless steel material coated or plated with a low-emissivity material such as ceramic, aluminum, or silver. The thickness of the coating or plating should be sufficient to address the surface effects of the specific microwave wavelengths generated by the microwave source 504 entering the degassing chamber 502. Similarly, in some embodiments, the low-emissivity lifting hoop 622 and the low-emissivity substrate support hoop 610 may be formed of stainless steel and coated or plated with a low-emissivity material such as ceramic, aluminum, or silver. The thickness of the coating or plating should be sufficient to address the surface effects of the specific microwave wavelengths generated by the microwave source 504 entering the degassing chamber 502.

[0039] In some cases, the inventors have discovered that only the portion of the first actuator shaft 526 and the second actuator shaft 512 that is exposed to the processing volume 550 of the degassing chamber 502 should be low emissivity. The remaining portion of the first actuator shaft 526 and the second actuator shaft 512 is never exposed to the processing volume 550 of the degassing chamber 502, and whether the remaining portion is low emissivity has no bearing on the reading of the IR temperature sensor 536. In some embodiments, the first actuator shaft 526 and the second actuator shaft 512 may be replaced by a two-piece actuator shaft, such as a first low emissivity upper shaft extension 726 supported by a first lower shaft 760 and a second low emissivity upper shaft extension 712 supported by a second lower shaft 762, such as Figure 7700 of FIG. 700. In some embodiments, the first low-emissivity upper shaft extension 726 and the second low-emissivity upper shaft extension 712 may be formed of a low-emissivity (0.1 or lower) material, such as aluminum, while the first lower shaft 760 and the second lower shaft 762 may be formed of a stainless steel material, etc. In some embodiments, the first low-emissivity upper shaft extension 726 and the second low-emissivity upper shaft extension 712 may be formed of stainless steel and coated or plated with a low-emissivity (0.1 or lower) material, such as ceramic, aluminum, or silver, etc., while the first lower shaft 760 and the second lower shaft 762 may be formed of an uncoated stainless steel material, etc.

[0040] Figure 8 A low emissivity actuator shaft is depicted, such as low emissivity actuator shaft 820 in view 800A and a two-piece actuator shaft 808 having a low emissivity upper shaft extension 802 and a lower shaft 804. In some embodiments, the low emissivity actuator shaft 820 has an upper flange or upper mating surface 816 to interface directly with a support area of ​​a hoop, such as a lifting hoop or a substrate support hoop. In some embodiments, at least one fastening hole 806 can provide threads for a screw, bolt, or other threaded or unthreaded fastener to retain the hoop to the low emissivity actuator shaft. In some embodiments, at least one fastening hole 806 can provide a press-fit contact surface for a pin or other fastener to retain the hoop to the low emissivity actuator shaft 820. The low emissivity actuator shaft 820 has a lower flange or lower mating surface 818 to interface directly with an actuator, with the actuator providing movement to the low emissivity actuator shaft 820, which in turn provides movement to the attached hoop.

[0041] In some embodiments, as depicted in view 800B, similar upper and lower mating surfaces may be provided. The low-emissivity upper shaft extension 802 may be formed with a recess 830 to mate with an extension or protrusion 810 formed on an upper end 832 of the lower shaft 804. The recess 830 and protrusion 810 allow the low-emissivity upper shaft extension 802 to be directly internally connected to the lower shaft 804 using a press fit, or by using a connecting member 814 (such as a screw or bolt, etc.) to hold the parts together. If the connecting member 814 is to be used, a lower recess 812 may be formed into the lower shaft 804 to allow access to insert the connecting member 814. If a press fit is used, the lower recess 812 and the connecting member 814 are not required. Similarly, if welding is used for connection, the lower recess 812 and the connecting member 814 are not required.

[0042] The ferrule used in the degassing chamber has an annular shape and when more than one ferrule is used in the degassing chamber, the ferrules may have different inner diameters 922, outer diameters 924, and / or thicknesses 926. Fig. 9, view 900A depicts a top view of a low emissivity collar 902 of a degassing chamber, and view 900B depicts a cross-sectional view of a low emissivity collar 902 of a degassing chamber, according to some embodiments. The low emissivity collar 902 has a mounting or mating area 904 to directly connect with a low emissivity actuator shaft (such as a one-piece shaft or a two-piece shaft). A connecting member (not shown) may be inserted into at least one mounting hole 906. The connecting member may be a screw, bolt, pin, or the like to mate with a recess in the low emissivity actuator shaft (see Figure 8 ). If the low-emissivity hoop 902 is used as a lifting hoop, a plurality of lifter risers 908 may be attached to the low-emissivity hoop 902 to increase the vertical height of the lifter 910. If the low-emissivity hoop 902 is used as a substrate support hoop, the plurality of lifter risers 908 and lifter 910 are not attached to the substrate support hoop because the upper surface 920 provides support for the substrate. In some embodiments, the lifter risers 908 and / or lifter 910 may be formed of a low-emissivity material and / or may be coated or plated with a low-emissivity material provided by the present technology on all surfaces or surfaces exposed to the processing space environment.

[0043] Embodiments according to the present principles can be implemented in hardware, solid, software, or any combination thereof. Embodiments can also be implemented as instructions stored using one or more computer-readable media, which can be read and executed by one or more processors. Computer-readable media may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computing platform or a "virtual machine" running on one or more computing platforms). For example, a computer-readable medium may include any suitable form of volatile or non-volatile memory. In some embodiments, a computer-readable medium may include a non-transient computer-readable medium.

[0044] While the foregoing is directed to embodiments of the present principles, other and further embodiments of the present principles may be devised without departing from the basic scope thereof.

Claims

1. A system for degassing a substrate, comprising: a degassing chamber having a microwave source and an infrared temperature sensor positioned in a bottom of the degassing chamber; at least one hoop configured to support or elevate the substrate, wherein the at least one hoop has an annular shape and is formed of at least one first material that is opaque to microwaves and has an emissivity of 0.1 or less; as well as at least one actuator having a movable vertical shaft, wherein each of the at least one actuator is attached below one of the at least one hoops at an outer periphery of the one of the at least one hoops, wherein at least a portion of the movable vertical shaft exposed to microwaves from the microwave source in the degassing chamber is formed of at least one second material that is opaque to microwaves and has an emissivity of 0.1 or less.

2. The system of claim 1, wherein the at least one first material comprises a first coating applied to the at least one hoop, the first coating being opaque to microwaves and having an emissivity of 0.1 or less.

3. The system of claim 2, wherein the first coating is a silver-based material or an aluminum-based material on a core material of stainless steel.

4. The system of claim 1, wherein the at least one second material comprises a second coating applied to at least the portion of the movable vertical shaft member that is exposed to microwaves from the microwave source in the degassing chamber, and wherein the second coating is opaque to microwaves and has an emissivity of 0.1 or less.

5. The system of claim 4, wherein the second coating is a silver-based material or an aluminum-based material on a core material of stainless steel, and wherein the silver-based material or the aluminum-based material has an emissivity of 0.1 or less.

6. The system of claim 1, wherein the movable vertical axis member comprises an upper portion of a third material and a lower portion of a fourth material, the third material being opaque to microwaves and having an emissivity of 0.1 or less.

7. The system of claim 1, wherein the movable vertical axis is formed of an aluminum-based material that is opaque to microwaves and has an emissivity of 0.1 or less.

8. The system of claim 1, further comprising: A proportional-integral-derivative (PID) controller is in communication with the infrared temperature sensor and the microwave source, wherein the PID controller is configured to control a processing temperature of the substrate based on readings from the infrared temperature sensor and adjustments to the microwave source.

9. The system of claim 1, wherein one of the at least one hoop is configured to support the substrate during processing in the degas chamber.

10. The system of claim 1, wherein one of the at least one hoop is configured to elevate the substrate before and after processing in the degas chamber.

11. An assembly for a degassing chamber, comprising: A movable vertical shaft configured to be installed in the degassing chamber, wherein the movable vertical shaft has a bottom end configured to be attached to an actuator and a top end configured to be attached to a hoop, the hoop being configured to support or elevate a substrate, wherein when installed in the degassing chamber, an upper portion of the movable vertical shaft is exposed to the internal environment of the degassing chamber, and wherein the movable vertical shaft is formed of at least one material that is opaque to microwaves and has an emissivity of 0.1 or less.

12. The assembly of claim 11, wherein the at least one material comprises a coating applied to at least the upper portion of the movable vertical shaft, wherein when the movable vertical shaft is mounted in the degassing chamber, at least the upper portion of the movable vertical shaft is exposed to the internal environment of the degassing chamber, wherein the coating is opaque to microwaves and has an emissivity of 0.1 or less.

13. The component of claim 12, wherein the coating is a silver-based material or an aluminum-based material on a core material of stainless steel, and wherein the silver-based material or the aluminum-based material has an emissivity of 0.1 or less.

14. The assembly of claim 11, wherein the movable vertical axis member includes the upper portion and a lower portion, wherein the upper portion is removable from the lower portion, and wherein the upper portion is formed of a material that is opaque to microwaves and has an emissivity of 0.1 or less, and the lower portion is formed of stainless steel.

15. The assembly of claim 14, wherein the upper portion and the lower portion are press-fitted together, welded together, threaded together, or bolted together.

16. The assembly of claim 11, wherein the movable vertical shaft is formed of an aluminum-based material that is opaque to microwaves and has an emissivity of 0.1 or less.

17. An assembly for a degassing chamber, comprising: A hoop configured to support or elevate a substrate in the degassing chamber, wherein the hoop has an annular shape having an area configured to be attached to a movable shaft connected to an actuator, wherein the hoop is formed of at least one material that is opaque to microwaves and has an emissivity of 0.1 or less.

18. The assembly of claim 17, wherein the at least one material comprises a coating applied to an outer surface of the ferrule, wherein the coating is opaque to microwaves and has an emissivity of 0.1 or less.

19. The assembly of claim 18, wherein the coating is a silver-based material or an aluminum-based material on a core material of stainless steel.

20. The assembly of claim 17, wherein the hoop is configured to support a substrate during processing in the degas chamber or to elevate the substrate before and after processing in the degas chamber.

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