Regenerator for forestage heating

Abstract

Semiconductor processing systems and system components for providing regenerative heating to forestage components are described. A system includes a plasma-based processing chamber. The processing chamber includes one or more fluid paths configured to circulate a heat transfer fluid. The system also includes one or more vacuum systems configured to discharge process gases from the process chamber, the one or more vacuum systems including one or more vacuum pumps and a foreline vent. The system includes a forestage regenerator. The forestage regenerator includes a regenerator housing at least partially surrounding the forestage vent, the regenerator housing including a heat transfer fluid input and a heat transfer fluid output, where the heat transfer fluid input is coupled to an output of the processing chamber.

Description

TECHNICAL FIELD

[0001] This specification relates to semiconductor systems, processes, and apparatuses. BACKGROUND

[0002] Plasma etching can be used in semiconductor processing to fabricate integrated circuits. Integrated circuits can be formed from a layer structure that includes a plurality of (e.g., two or more) layer compositions. Different etching gas chemistries (e.g., different mixtures of gases) can be used to form a plasma in a processing environment, such that a given etching gas chemistry can have increased precision and higher selectivity for a layer composition to be etched. Plasma etching is typically performed within a low pressure processing chamber. One or more vacuum pumps exhaust gas molecules from the processing chamber through a foreline. SUMMARY

[0003] This specification describes techniques for using excess thermal energy from a heat transfer fluid used to heat a plasma processing chamber to heat foreline components of a plasma-based processing system. The plasma-based processing system generates a plasma within a processing region to perform a particular process, such as a plasma etch of a substrate held within a processing chamber. The processing chamber is coupled to a foreline that provides an exhaust path when a vacuum is generated and maintained within the processing chamber. Maintaining the vacuum includes evacuating byproducts generated by the plasma etch process. The byproducts can include various polymers. The foreline is heated to a temperature similar to the temperature of the processing chamber to prevent the exhausted byproducts from precipitating on or adhering to an inner liner of the foreline. If allowed to accumulate, the polymers can eventually adversely affect the performance of the plasma-based processing system.

[0004] To maintain a desired temperature within the processing chamber, the processing chamber is heated by circulating a high temperature heat transfer fluid that transfers heat to the chamber and away from the processing chamber. This specification describes techniques for directing the heated heat transfer fluid that exits the processing chamber to a foreline regenerator housing prior to transferring the fluid to a heat exchanger. Thus, the foreline is heated using a regenerative heater that utilizes waste heat retained by the heat transfer fluid to provide heating.

[0005] Generally speaking, an innovative aspect of the objects described herein can be embodied in a system for semiconductor processing. The system includes a plasma-based processing chamber comprising one or more fluid paths configured to circulate a heat transfer fluid. The system also includes one or more vacuum systems configured to exhaust process gases from the processing chamber, the one or more vacuum systems comprising one or more vacuum pumps and a foreline vent. The system further includes a foreline regenerator comprising a regenerator housing at least partially surrounding the foreline vent. The regenerator housing includes a heat transfer fluid input and a heat transfer fluid output. The heat transfer fluid input is coupled to the output of the processing chamber.

[0006] Generally speaking, one innovative aspect of the objects described herein can be embodied in a pre-stage regenerator comprising a housing surrounding at least a portion of a pre-stage vent of a plasma-based processing system. The housing is configured to provide a gap between an outer surface of the pre-stage vent and an inner surface of the housing. The pre-stage regenerator also comprises a heat transfer fluid input port configured to receive a heat transfer fluid and input the heat transfer fluid into the gap. The pre-stage regenerator also comprises a heat transfer fluid output port configured to output the heat transfer fluid from the gap.

[0007] Generally speaking, one innovative aspect of the objectives described herein can be embodied in a method for heating a front-end component. The method includes receiving a heat transfer fluid output from a plasma-based substrate processing chamber at an input port of a regenerator. The method further includes flowing the heat transfer fluid between the input port of the regenerator and an output port of the regenerator to heat the front-end component. Flowing the heat transfer fluid includes transferring the heat transfer fluid from the input port to a regenerator housing. The regenerator housing includes a housing that at least partially surrounds the front-end component, the housing providing a fluid path within a space between an outer surface of the front-end component and an inner surface of the housing. The method includes outputting the heat transfer fluid from the output port of the regenerator.

[0008] The objectives described in this specification can be achieved in these and other embodiments to realize one or more of the following advantages. Heating the foreline prevents process byproducts in the exhaust from adhering to the inner surface of the foreline. A regenerative heating process using a heat transfer fluid that circulates from the processing chamber allows the foreline to be heated to substantially the same temperature as the processing chamber, which prevents precipitation of byproducts. Using waste heat from the processing chamber eliminates the need for one or more separate electric heaters positioned around the foreline. This reduces manufacturing and operating costs. In addition, as opposed to separate electric heaters, using heat from the heat transfer fluid can eliminate the need to regulate the heater temperature because the processing chamber provides the heat transfer fluid at a constant temperature. In addition, using waste heat allows for an environmentally friendly and sustainable solution that does not require excess electricity.

[0009] While the remaining disclosure will describe the innovative technology in the context of a particular type of plasma-based processing chamber in which the disclosed technology is used, it will be readily understood that the systems and methods are equally applicable to various other types of plasma-based substrate processing chambers. As such, the technology should not be considered so limited as to only be used with the etch-based processes described. Prior to describing the methods or operations of the systems and example process sequences according to some embodiments of the technology, the present disclosure will discuss a possible system and chamber that can be used with the technology. It will be understood that the technology is not limited to the equipment described, and the processes discussed can be performed in any number of processing chambers and systems. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 A schematic cross-sectional view of an example processing chamber is illustrated.

[0011] Figure 2 A schematic view of an example heat transfer loop for a plasma-based processing system is illustrated.

[0012] Figure 3 A schematic cross-sectional view of an example foreline having a regenerative heater housing is illustrated.

[0013] Figure 4 A cross-sectional view of the example regenerative foreline along line A-A is illustrated. Figure 3 A cross-sectional view of the example regenerative foreline is illustrated.

[0014] Figure 5 A flowchart of an example process for heating a foreline is illustrated.

[0015] Like reference numbers and designations in the various drawings indicate like elements. DETAILED DESCRIPTION

[0016] The present specification describes technology for heating foreline components of a plasma-based processing system using excess heat from a plasma processing chamber. A foreline is coupled to one or more vacuum components of a plasma-based processing system and is used to exhaust gases and byproducts pumped from a processing chamber. At least a portion of the foreline is enclosed by a regenerator housing. A high-temperature heat transfer fluid exiting the processing chamber is circulated within the regenerator housing to provide heating to the foreline. The heating prevents process byproducts from adhering to the interior walls of the foreline.

[0017] Figure 1A schematic cross-sectional view of an example processing chamber 100 suitable for etching one or more material layers disposed on a substrate 103 (also referred to as a "wafer") in the processing chamber 100 (e.g., a plasma processing chamber) is shown. The processing chamber 100 includes a chamber body 105 that defines a chamber volume 101 in which a substrate can be processed. The chamber body 105 has a sidewall 112 and a bottom 118 coupled to a floor 126. The sidewall 112 can include a liner 115 for protecting the sidewall 112 and extending the time between maintenance cycles of the plasma processing chamber 100. The chamber body 105 supports a chamber lid 110 to enclose the chamber volume 101. The chamber body 105 can be fabricated, for example, from aluminum or other suitable material. A substrate access port 113 is formed through the sidewall 112 of the chamber body 105, which can facilitate the transfer of the substrate 103 into and out of the plasma processing chamber 100. The access port 113 can be coupled with a transfer chamber and / or other chambers (not shown) of a substrate processing system, for example, for performing other processes on the substrate. A pumping port 145 is formed through the bottom 118 of the chamber body 105 and is connected to the chamber volume 101. A pumping device can be coupled to the chamber volume 101 through the pumping port 145 to evacuate and control the pressure within the processing volume. The pumping device can include one or more vacuum pumps and throttle valves that output gas and processing byproducts to a foreline.

[0018] The chamber volume 101 includes a processing region 107, for example, a station for processing a substrate. A substrate support 135 can be disposed in the processing region 107 of the chamber volume 101 to support the substrate 103 during processing. The substrate support 135 can include an electrostatic chuck 122 for holding the substrate 103 during processing. The electrostatic chuck ("ESC") 122 can use electrostatic attraction to hold the substrate 103 to the substrate support 135. The ESC 122 can be powered by a radio frequency ("RF") power supply 125 integrated with a matching circuit 124. The ESC 122 can include an electrode 121 embedded within a dielectric body. The electrode 121 can be coupled with the RF power supply 125 and can provide a bias to the ESC 122 and a substrate 103 disposed on the pedestal that attracts plasma ions formed from processing gases in the chamber volume 101. The RF power supply 125 can be cycled on and off, or pulsed, during processing of the substrate 103. The ESC 122 can have an isolator 128 for making the sidewalls of the ESC 122 less attractive to plasma to extend the maintenance life cycle of the ESC 122. Further, the substrate support 135 can have a cathode liner 136 for protecting the sidewalls of the substrate support 135 from the plasma gases and extending the time between maintenance of the plasma processing chamber 100.

[0019] Electrodes 121 can be coupled with a DC power source 150. Power source 150 can provide a chucking voltage of about 200 volts to about 2000 volts to electrodes 121. Power source 150 can also include a system controller for controlling the operation of electrodes 121 by directing a DC current to electrodes 121 for chucking and de-chucking substrate 103. ESC 122 can include a heater disposed within ESC 122 and connected to power source for heating the substrate, while a cooling base 129 supporting ESC 122 can include conduits for circulating a heat transfer fluid to maintain the temperature of ESC 122 and the substrate 103 disposed thereon. ESC 122 can be configured to perform in a temperature range required by the thermal budget of the elements being fabricated on substrate 103. For example, depending on the process being performed, ESC 122 can be configured to maintain substrate 103 at a temperature of about -150 °C or lower to about 500 °C or higher. A cover ring 130 can be disposed on ESC 122 and along the perimeter of substrate support 135. Cover ring 130 can be configured to confine etching gas to a desired portion of the exposed top surface of substrate 103 while shielding the top surface of substrate support 135 from the plasma environment inside plasma processing chamber 100.

[0020] A gas panel 160 (also referred to herein as a "gas distribution manifold") can be coupled with chamber body 105 through gas lines 167 through chamber lid 110 to supply process gases into chamber volume 101. Gas panel 160 can include one or more process gas sources 161, 162, 163, 164 and can additionally include inert, non-reactive, and reactive gases, as can be used for any number of suitable processes. Examples of process gases that can be supplied through gas panel 160 include, but are not limited to, hydrocarbon-containing gases, including methane, sulfur hexafluoride, silicon chloride, silicon tetrachloride, carbon tetrafluoride, hydrogen bromide. Process gases that can be supplied through the gas panel can include, but are not limited to, argon, chlorine, nitrogen, helium, or oxygen, sulfur dioxide, and any number of additional materials. Further, process gases can include gases containing nitrogen, chlorine, fluorine, oxygen, or hydrogen, including, for example, BCl3, C2F4, C4F8, C4F6, CHF3, CH2F2, CH3F, NF3, NH3, CO2, SO2, CO, N2, NO2, N2O, and H2, as well as any number of additional suitable precursors. Process gases from process gas sources (e.g., sources 161, 162, 163, 164) can be combined to form one or more etching gas mixtures. For example, gas panel 160 includes one or more process gas sources specific to oxide-based etching chemistries. In another example, gas panel 160 includes one or more process gas sources specific to nitride-based etching chemistries.

[0021] Gas panel 160 includes various valves and other components to control the flow of process gases from sources. Valves 166 can control the flow of process gases from gas sources 161, 162, 163, 164 of gas panel 160. Operation of the valves, pressure regulators, and / or mass flow controllers can be controlled by controller 165. Controller 165 can be operatively coupled to an electro-valve (EV) manifold (not shown) to control actuation of one or more of the valves, pressure regulators, and / or mass flow controllers.

[0022] Lid 110 can incorporate gas delivery nozzles 114. Gas delivery nozzles 114 can include one or more openings for introducing process gases from sources 161, 162, 163, 164 of gas panel 160 into chamber volume 101. After process gases are introduced into plasma processing chamber 100, the gases can be energized to form a plasma. An antenna 148, such as one or more inductor coils, can be provided proximate to plasma processing chamber 100. An antenna power supply 142 can power antenna 148 through a matching circuit 141 to inductively couple energy, such as RF energy, to the process gases to sustain a plasma formed from the process gases in chamber volume 101 of plasma processing chamber 100. Operation of power supply 142 can be controlled by a controller, such as controller 165, which also controls operation of other components in plasma processing chamber 100.

[0023] Although Figure 1 While an inductively coupled plasma source is shown, the general chamber and pre- line described below can be used with other types of plasma sources, including capacitively coupled plasma sources.

[0024] Controller 165 can be used to control process sequences, adjust gas flow from gas panel 160 into plasma processing chamber 100, and other process parameters. When executed by a computing device having one or more processors (e.g., central processing units (CPUs)) in data communication with one or more memory storage devices, software routines transform the computing device into a special purpose computer, such as a controller, which can control plasma processing chamber 100 such that processes in accordance with the present disclosure are performed. Software routines can also be stored and / or executed by one or more other controllers, which can be associated with plasma processing chamber 100.

[0025] In some embodiments, at the end point of the etching process for the wafer, an automated or semi-automated robotic manipulator (not shown) can be used to move the wafer from the substrate support out of the processing chamber, e.g., through the substrate access port 113. For example, the robotic manipulator can move the wafer to another chamber (or another location) to perform another step in the manufacturing process.

[0026] Although about Figure 1 While a processing chamber is described as including a substrate support disposed within a processing region of a chamber volume, two or more substrate supports may be disposed within the same chamber volume in respective processing regions (e.g., in respective processing stations). For example, processing chamber 100 may be a tandem processing chamber including two processing regions, each processing region having a respective substrate support configured to hold a respective wafer during an etching process. Processing chamber 100 may include two or more processing regions within chamber volume 101 to facilitate parallel processing of two or more substrates in the respective processing regions. The processing regions may be substantially isolated such that an etching process in a first processing region has minimal effect on an etching process in a second processing region, and vice versa. In a tandem processing chamber, there may be two separate foreline lines, one for each processing region. Each foreline may include a foreline regenerator.

[0027] Figure 2 A schematic diagram of an exemplary heat transfer loop 200 for a plasma based processing system is shown. The heat transfer loop includes a heat transfer fluid "in" path 201 and a heat transfer fluid "out" path 203.

[0028] The heat transfer fluid "in" path 201 begins at a fluid line 205 exiting a heat exchanger 202 for delivering the heat transfer fluid. In some embodiments, the heat transfer fluid exiting the heat exchanger 202 has a temperature corresponding to the designated temperature of the processing chamber. The temperature of the heat transfer fluid may be, for example, 65 degrees Celsius or 90 degrees Celsius.

[0029] The heat exchanger 202 receives a heat transfer fluid at an input port and outputs the heat transfer fluid at a specified temperature at an output port coupled to the fluid line 205. The heat exchanger 202 can be, for example, a chamber that allows heat to be transferred between a heat transfer fluid and another heat transfer fluid within the heat exchanger 202 without direct contact between the two fluids. For example, the chamber can have a path that transports the heat transfer fluid from the input port to the output port. The path can be a coil, a zigzag, or other path that extends the path of the heat transfer fluid through the chamber. The chamber can also include a second heat transfer fluid that circulates through the chamber and around the path. Heat is exchanged to achieve the desired output temperature of the heat transfer fluid.

[0030] Fluid lines 205 are coupled to, for example, a facility box 204 for a plasma-based processing system. The facility box 204 provides a manifold for connecting components of the plasma-based processing system to external components. Thus, for example, the facility box 204 allows for coupling fluid lines 205 to the plasma-based processing system. In some alternative embodiments, a heat exchanger can be integrated within the plasma-based processing system, eliminating the need for the facility box 204 to couple fluid lines to the heat exchanger.

[0031] Fluid line 207 exits facility box 204 and enters process chamber 206. Process chamber 206 may be similar to Figure 1 The processing chamber 100 is heated by a heat transfer fluid to maintain a specific chamber temperature, for example, 65 degrees Celsius or 90 degrees Celsius.

[0032] The fluid "exit" path 203 begins with the heat transfer fluid leaving the processing chamber 206 and entering fluid line 209. Fluid line 209 couples the processing chamber 206 to the input of the foreline regenerator, as shown in box 208. The foreline includes a regenerator housing that at least partially surrounds the foreline so that the heat transfer fluid input to the foreline fills the space between the regenerator housing and the outer surface of the foreline. Fluid line 209 and, as appropriate, other fluid lines can be insulated to reduce heat losses over the distance from the processing chamber 206 to the foreline regenerator. Losses over short distances are negligible, so that the temperature of the heat transfer fluid entering the foreline regenerator is essentially the same as the temperature of the heat transfer fluid leaving the processing chamber 206. Thus, if the temperature of the processing chamber is maintained constant, the temperature of the heat transfer fluid is also constant.

[0033] The foreline is coupled to a flow valve 210 and a turbomolecular pump (referred to herein as a turbo pump) 212 as part of the vacuum components of the plasma-based processing system. While the flow valve 210 and the turbo pump 212 provide exhaust from the processing chamber 206, they provide input to the foreline. The foreline further includes an output vent for outputting exhaust gases and process byproducts. Figure 3 The vacuum components are further described. The output vent may be coupled to one or more other external systems that process the exhaust, such as for removing byproducts and recycling certain process gases.

[0034] The heat transfer fluid exits the regenerator into fluid line 211. Fluid line 211 couples the pre-regenerator with the utility box 204. Fluid line 213 couples the utility box 204 with the input of the heat exchanger 202, thereby completing the heat transfer circuit, eg, as a closed loop system.

[0035] Figure 3A schematic cross-sectional view 300 of an example foreline with a regenerative heater is illustrated. In particular, cross-sectional view 300 represents an enlarged view of components within block 208 of Figure 2

[0036] The regenerative foreline 302 includes a regenerator housing 304 and a foreline 306. The foreline 306 is coupled to a first isolation valve 308 and a second isolation valve 310. The first isolation valve 308 is coupled to the flow valve 210. The second isolation valve 310 is coupled to the turbo pump 212. The foreline 306 is further coupled to a vent 312. In some embodiments, process gas of a plasma processing chamber can be recovered from exhaust gas. In some embodiments, the foreline 306 is manufactured from stainless steel. For example, the foreline can be manufactured from SST 316L, which is a specific stainless steel alloy containing molybdenum and having good corrosion resistance.

[0037] During operation of a plasma processing chamber (e.g., plasma processing chamber 206), a vacuum is formed within the processing chamber. Based on the desired vacuum level, a multi-step process can be used to form the vacuum. For example, an initial roughing vacuum pump can be used to reach a first pressure level within the processing chamber, e.g., to reduce the pressure to substantially 100 mTorr. The first vacuum level created by the roughing vacuum pump is directed through the first isolation valve 308 and bypasses the turbo pump 212 to the foreline 306. During the roughing vacuum process, the first isolation valve 308 can be open, while the second isolation valve 310 can be closed. In some embodiments, the flow valve 210 is a symmetric flow valve that provides high throughput and reduces choked flow between the processing chamber and the vacuum pump.

[0038] A second vacuum phase to obtain a greater vacuum can be performed by the turbo pump 212. During the second vacuum phase, the first isolation valve 308 can be closed and the second isolation valve 310 can be open. Gas molecules from the processing chamber pass through the flow valve 210 and are output through the second isolation valve 310 to the foreline 306 by the turbo pump 212.

[0039] After a vacuum with a specified pressure is formed, the turbo pump 212 maintains the pressure in the processing chamber. As described above, in a plasma processing chamber, a processing operation can be performed using a plasma on a substrate. A specific process gas is input into the chamber. Byproducts of the input process gas are vented through the foreline 306 by the turbo pump 212 to maintain the specified pressure within the processing chamber and to prevent additional matter of the processing byproducts from interfering with the plasma processing operation.

[0040] ​A particular processing operation may be configured for a set temperature in the processing chamber, for example, 65°C or 90°C. To maintain the desired temperature, the chamber body of the processing chamber includes a fluid path through which a heat transfer fluid is continuously circulated, for example, to remove excess heat generated by the plasma processing. The heat transfer fluid may be selected based on specific performance parameters, such as the ability to operate in a specific temperature range and chemical stability. The heat transfer fluid may be, for example, a fluorinated fluid, such as one comprising PFPE is perfluoropolyether.

[0041] Without heating the foreline 306, byproducts in the hot exhaust gas passing through the foreline may cool and adhere to the inner surface of the foreline 306. The foreline 306 is thus heated to prevent the byproducts from being deposited on the inner surface of the foreline 306.

[0042] The regenerator housing 304 encloses the sidewall of the foreline 306. The regenerator housing 304 provides a space between the outer surface of the foreline sidewall and the regenerator housing 304. The inlet 316 supplies high-temperature heat transfer fluid that has exited the processing chamber to fill the space between the outer surface of the foreline sidewall and the regenerator housing 304. The heat transfer fluid entering the regenerator housing 304 can be substantially equal to the temperature of the processing chamber, for example, 65° C. or 90° C.

[0043] Figure 4 The diagram shows the Figure 3 A cross-sectional view 400 of an example regeneration foreline 302 is shown. As shown in the cross-sectional view 400, the regenerator housing 304 surrounds the foreline 306. Exhaust gas 402 passes through the foreline 306 toward the exhaust. As a heat transfer fluid 404 fills the space between the foreline 306 and the regenerator housing 304, the heat transfer fluid heats the foreline.

[0044] The high temperature heat transfer fluid fills the space formed by the regenerator housing 304 until it reaches the output port 318. The heat transfer fluid output from the regenerator housing proceeds to a heat exchanger after which the heat transfer fluid can be circulated back to the process chamber, for example, as Figure 2 Shown in.

[0045] exist Figure 3 In the example regenerator housing shown, the input port 316 is located near the second isolation valve 310. However, the input port 316 can be located in other locations, for example, near the discharge port 312. The output port 318 is shown near the first isolation valve 308 so that the entire housing can be filled with heat transfer fluid. However, in some embodiments, the output port can be located in another location.

[0046] The regenerator enclosure 304 can be a single layer of material or multiple layers. For example, the inner layer of the regenerator enclosure 304 can be metal surrounded by a layer of insulation to help maintain the heating of the foreline 306. In some implementations, the inner layer is composed of stainless steel. Alternatively, for a single layer enclosure, the entire body can be composed of stainless steel. Similar to the foreline, the regenerator enclosure can be formed of a specific stainless steel alloy, such as SST 316.

[0047] In some alternative implementations, the regenerator enclosure 304 can include an insulated enclosure layer and a coil inner tube wrapped around the foreline. A heat transfer fluid can pass through the coil from an input port to an output port, which is heated by the fluid. The heat is then transferred to the foreline.

[0048] Figure 5 is a flow diagram of an example process 500 for heating a foreline. For convenience, the process 500 will be described with respect to the system that performs the process 500, e.g., a cooling and heating system for a plasma-based processing system.

[0049] The system extracts a high temperature heat transfer fluid from a plasma-based processing chamber (502). The plasma-based processing chamber can be maintained at a particular temperature, e.g., 65°C or 90°C. A fluid line can input the heat transfer fluid to the plasma-based processing chamber. For example, the processing chamber sidewall can include a fluid path that allows the heat transfer fluid to absorb excess heat from the plasma-based processing chamber as it passes through the fluid path. The heat transfer fluid is then output from the plasma-based processing chamber.

[0050] The system supplies the high temperature heat transfer fluid to a regenerator enclosure to heat the foreline (504). The heat transfer fluid fills a space around at least a portion of the foreline to heat the foreline. Heating the foreline can prevent process byproducts that exist as vacuum exhaust from adhering to the inner walls of the foreline. The high temperature heat transfer fluid can enter the regenerator enclosure at a lower point with respect to the ground and exit at a higher point to ensure that the heat transfer fluid rises to surround the foreline as it progresses to the output.

[0051] Because the processing chamber is maintained at a particular temperature, the temperature of the outgoing heat transfer fluid is generally known and constant. Using an insulated fluid line reduces heat loss between the processing chamber and the regenerator enclosure, such that a consistent heat transfer fluid temperature is provided to the regenerator enclosure. As a result, temperature monitoring or regulation of the regenerator enclosure can not be needed, as the supplied temperature is known and constant.

[0052] The system outputs the heat transfer fluid from the regenerator enclosure and directs the heat transfer fluid to a heat exchanger (506). The heat exchanger transfers heat such that the heat transfer fluid exiting the heat exchanger has a specified temperature for circulation back to the process chamber temperature. One or more intermediate components can be positioned between the regenerator enclosure and the heat exchanger. For example, a facility connection point can be used as a coupling point between components within the plasma processing system and external components (e.g., an external heat exchanger).

[0053] The system provides the heat transfer fluid from the heat exchanger to the plasma-based process chamber (508). The heat transfer fluid exiting the heat exchanger is directed back to the plasma-based process chamber to complete the heat transfer loop. Again, the heat transfer fluid can be directed through one or more intermediate components, such as a facility connection point, prior to reaching the heat transfer fluid input of the plasma-based process chamber.

[0054] Although this description contains many specifics, these should not be construed as limiting the scope of the application but merely as describing a particular implementation, which can be embodied in a specific form. Some features described in the context of separate embodiments can also be implemented together. Conversely, various features described in the context of one embodiment can also be implemented separately or in any appropriate subcombination. Also, although operational can be described herein as a sequential process, some of the operations can in fact be performed in parallel, concurrently, or in a different order than described. Further, as

[0055] Similarly, while operations are depicted in the drawings and recited in the claims in a particular order, this should not be understood as requiring such operations to be performed in the particular order described or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing can be advantageous. Moreover, the separation of various system modules and components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

[0056] Particular implementations of the subject matter have been described. Other implementations are within the scope of the following claims. For example, the acts recited in the claims can be performed in a different order and still achieve desirable results. As one example, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve the desired results. In some instances, multitasking and parallel processing can be advantageous.

Claims

1. A system comprising: a plasma-based process chamber, the process chamber including one or more fluid paths configured as a circulating heat transfer fluid; one or more vacuum systems configured to exhaust process gas from the process chamber, the one or more vacuum systems including one or more vacuum pumps and a foreline; and a foreline regenerator, the foreline regenerator including: a regenerator housing at least partially surrounding the foreline, the regenerator housing including a heat transfer fluid input and a heat transfer fluid output, wherein the heat transfer fluid input is coupled to an output of the process chamber.

2. The system of claim 1, wherein the regenerator housing provides a spacing between an inner surface of the regenerator housing and an outer surface of the foreline.

3. The system of claim 2, wherein heat transfer fluid input to the heat transfer fluid input fills the spacing between the inner surface of the regenerator housing and an outer surface of the foreline and between the heat transfer fluid input and the heat transfer fluid output.

4. The system of claim 1, wherein the foreline includes a first exhaust branch coupled to a roughing vacuum pump, a second exhaust branch coupled to a turbo pump, and a vent coupled to the first and second exhaust branches, wherein the heat transfer fluid input is positioned proximate the second exhaust branch and the heat transfer fluid output is positioned proximate the first exhaust branch.

5. The system of claim 1, including an insulated fluid line coupling the heat transfer fluid output of the process chamber and the heat transfer fluid input of the regenerator housing.

6. The system of claim 1, further including one or more fluid lines coupling the heat transfer fluid output of the regenerator housing to a heat exchanger and one or more fluid lines coupling the heat exchanger to an input of the process chamber, wherein the set of fluid lines complete a heat transfer loop.

7. The system of claim 1, the foreline regenerator further including a coil fluid path coupling the heat transfer fluid input and the heat transfer fluid output, the coil fluid path positioned within a space between the regenerator housing and the foreline.

8. A foreline regenerator, the foreline regenerator including: a housing surrounding at least a portion of a foreline of a plasma-based process system, the housing configured to provide a spacing between an outer surface of the foreline and an inner surface of the housing; a heat transfer fluid input port configured to receive a heat transfer fluid and input the heat transfer fluid to the spacing; and a heat transfer fluid output port configured to output heat transfer fluid from the spacing.

9. The foreline regenerator of claim 8, wherein heat transfer fluid input to the heat transfer fluid input port fills the spacing between the inner surface of the regenerator housing and an outer surface of the foreline and between the heat transfer fluid input and the heat transfer fluid output port.

10. The frontside regenerator of claim 8, wherein the frontside regenerator heats the frontside line to a consistent temperature of substantially 65 degrees Celsius during operation.

11. The frontside regenerator of claim 8, wherein the heat transfer input port is positioned proximate to a turbomolecular vacuum pump exhaust relative to a portion of the frontside vent.

12. The frontside regenerator of claim 11, wherein the heat transfer output port is positioned proximate to a roughing vacuum pump exhaust relative to a portion of the frontside vent.

13. The frontside regenerator of claim 8, wherein the regenerator housing includes an inner layer formed of stainless steel and an outer insulation layer.

14. The frontside regenerator of claim 8, wherein the gap comprises a coil-shaped fluid path wrapped around the frontside vent and coupling the heat transfer input port to the heat transfer output port.

15. A method of heating a frontside component, the method comprising: receiving, at an input port of a regenerator, heat transfer fluid output from a plasma-based substrate processing chamber; flowing the heat transfer fluid between the input port of the regenerator and an output port of the regenerator to heat the frontside component, wherein flowing the heat transfer fluid comprises: passing the heat transfer fluid from the input port to a regenerator housing, the regenerator housing comprising a housing at least partially surrounding the frontside component, the housing providing a fluid path within a gap between an outer surface of the frontside component and an inner surface of the housing; and outputting the heat transfer fluid from the output port of the regenerator.

16. The method of claim 15, wherein receiving the heat transfer fluid output from a plasma-based substrate processing chamber comprises: passing the heat transfer fluid through an insulated fluid line from the processing chamber to the input port of the regenerator.

17. The method of claim 15, wherein flowing the heat transfer fluid between the input port of the regenerator and the output port of the regenerator heats the frontside component to substantially 65 degrees Celsius.

18. The method of claim 15, wherein the output port of the regenerator is coupled to a heat exchanger, and wherein the heat exchanger is coupled to an input of the plasma-based substrate processing chamber, the method further comprising: circulating heat transfer fluid in a closed loop between the processing chamber, the regenerator, and the heat exchanger.

19. The method of claim 15, wherein the heat transfer fluid output from the processing chamber has a constant temperature, such that the frontside line is also heated to a constant temperature.

20. The method of claim 15, wherein flowing the heat transfer fluid between the input port of the regenerator and the output port of the regenerator comprises: inputting the heat transfer fluid at a lower point relative to a floor in the regenerator and outputting the heat transfer fluid at a higher point relative to the floor in the regenerator.

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