1. Field
Embodiments of the present invention generally relate to semiconductor, flat panel, photovoltaic or other silicon and thin film processing chambers and equipment, and more specifically to methods and apparatus for recovering heat from such processing systems.
2. Description of the Related Art
In semiconductor, flat panel, photovoltaic, and other silicon or thin film processing systems, many processes require the pre-heating of liquid or gaseous reagents prior to use in the processing system. The reagents are often heated using a heater, such as a point of use heater, or a similar heating apparatus, immediately prior to use. After processing, effluents (e.g., used, or “dirty” water or chemicals, gaseous exhaust, and the like) disposed from the processing system is typically directed to a waste treatment system to treat and/or dispose of the effluent. Very often these effluents need to be cooled down before they can be disposed or diluted with a cooler medium or dissipate heat into the ambient air, which in turn often needs to be removed as well.
As pre-heating of the reagents requires a significant amount of energy, which can increase manufacturing costs, the present invention is directed towards methods and apparatus for recovering heat from disposed effluents to facilitate reduction in such manufacturing costs.
Methods and apparatus for recovering heat from disposed effluents are disclosed herein. In some embodiments, an apparatus includes a substrate processing system comprising a process chamber configured for liquid processes; a first heat exchanger having first and second sides configured to transfer heat therebetween, wherein the first side is configured to flow a liquid reagent therethrough and into the process chamber, and wherein the second side is configured to flow an effluent from the process chamber therethrough; and a heater disposed in line with the first side of the first heat exchanger to heat the liquid reagent prior to entering the process chamber.
In some embodiments, a substrate processing system may include a waste heat source for providing a first waste fluid having waste heat stored therein; a first process chamber having a reagent source coupled thereto and configured to provide a reagent to an inner volume of the first process chamber; and a heat pump coupled between the waste heat source and an incoming reagent line that flows the reagent into the inner volume of the process chamber, the heat pump configured to transfer heat from the waste heat source to the reagent in the incoming reagent line. In some embodiments, the heat pump may include a compressor and a first heat exchanger, wherein the compressor is coupled in line with the waste heat source and a first side of the heat exchanger to pressurize the first waste fluid and prior to the first waste fluid flowing through the first side of the heat exchanger, and wherein a second side of the first heat exchanger is configured to flow the reagent therethrough.
In some embodiments, the system further includes a heater disposed in line with the second side of the first heat exchanger to heat the reagent prior to entering the first process chamber. In some embodiments, the waste heat source may comprise one or more of an effluent from a process chamber configured for liquid or gaseous processes, a compressed air system, an air separation compressor, a gaseous exhaust or a liquid coolant from an abatement device, hot air or a liquid coolant from electrical and/or mechanical equipment, or the like.
In some embodiments, the first process chamber is configured for liquid processes, and wherein the waste heat source comprises a second process chamber configured for gaseous processes and providing the first waste heat as gaseous exhaust from the second process chamber.
In some embodiments, the system further includes a second heat exchanger having first and second sides configured to transfer heat therebetween, wherein the first side of the second heat exchanger is configured to flow the reagent therethrough and into the first process chamber, and wherein the second side of the second heat exchanger is configured to flow a second waste fluid exhausted from the first process chamber therethrough.
In one aspect of the invention, methods for recovering heat from disposed effluents are disclosed. In some embodiments, a method for processing a substrate includes providing a process chamber configured for liquid processes coupled to a heat exchanger having a first side for flowing a liquid reagent into the processing system and a second side for flowing an effluent from the process chamber—directly or pumped from an intermediate reservoir; pre-heating the liquid reagent by transferring heat from the effluent flowing through the second side of the heat exchanger to the reagent flowing through the first side of the heat exchanger; and heating the pre-heated liquid reagent to a desired temperature using a heater disposed between the heat exchanger and the process chamber.
In some embodiments, a method for processing a substrate includes flowing a liquid reagent through a first side of a heat exchanger to preheat the liquid reagent; heating the pre-heated liquid reagent to a desired temperature using a heater; flowing the heated liquid reagent to a process chamber configured for liquid processes; and flowing a process effluent from the chamber (directly or pumped from an intermediate reservoir) through a second side of the heat exchanger to pre-heat the liquid reagent flowing through the first side of the heat exchanger.
In some embodiments, a method for processing a substrate may include flowing a reagent through a heat pump coupled to a waste heat source to heat the reagent by transferring heat from the waste heat source to the reagent; and flowing the heated reagent to a process chamber to process the substrate. In some embodiments, a method for processing a substrate may include flowing a reagent through a first side of a first heat exchanger to heat the reagent by transferring heat from a pressurized waste heat fluid flowing through a second side of the first heat exchanger; and flowing the heated reagent to a process chamber to process the substrate. In some embodiments, the waste heat source or the waste heat fluid may comprise one or more of a liquid waste fluid, exhaust or liquid coolant from a process chamber configured for gaseous processes, a compressed air system, an air separation compressor a gaseous exhaust or an liquid coolant from an abatement device, hot air or a liquid coolant from electrical and/or mechanical equipment, or the like.
Other and further embodiments are described in the detailed description, below.
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. The above drawings are not to scale and may be simplified for illustrative purposes.
Methods and apparatus for recovering and utilizing heat from disposed effluents in processing systems are disclosed herein. The inventive methods and apparatus advantageously facilitate reduced energy consumption in substrate processing systems (for example, semiconductor, flat panel, photovoltaic or other silicon and thin film processing systems) by utilizing waste heat from the processing system (for example, disposed effluent from a process chamber as well as waste heat generated by other components of the processing system) to pre-heat fluids prior to use in the same and/or other processing systems. The reduction of heat in the disposed effluent is further advantageous for subsequent processing of the disposed effluents, such as by abatement or other means of disposal.
As shown in
The substrate 114 may be disposed in a recess 116 formed on the surface of the substrate support 112. The recess 116 may be utilized, for example, to immerse the substrate 114 in bath of reagents. The reagents may be supplied by a nozzle 118 disposed above the support 112. The recess 116 need not be limited to a depression formed in the surface of the substrate support. As such, the recess 116 may be formed, for example, by an edge ring or bracket (not shown) configured to support the substrate 114 at a peripheral of the substrate, where the substrate 114 forms the base of the recess. The substrate support may further include a plate (not shown) disposed about 3 millimeters (mm) below the backside of the substrate 114. The plate may include transducers (not shown) that are capable of emitting sound in the megasonic frequency range, or between about 800 to about 2000 kHz.
A fluid feed port (not shown) can be disposed in the substrate support 112 and through the plate to supply fluid to fill an about 3 mm gap (not shown) between the plate and the backside of the substrate 112 with a liquid during processing. The liquid can act as a carrier for transferring megasonic energy to the substrate 114, for example, as a means of providing agitation during a cleaning process, or as a way to heat the wafer. The substrate support 112 may further include a lift/rotation mechanism (not shown) which may, for example, be utilized to controllably spread a reagent uniformly across the frontside surface of the substrate 114. The top of the process chamber 102 can include a filter (not shown) to clean air that is flowing into the processing chamber and onto the frontside of the substrate 114.
The nozzle 118 may be coupled to an incoming fluid line 104 at a wall of the process chamber 102. The nozzle can be positioned to direct flow of a gas, vapor, or a liquid onto the frontside surface of the substrate 114. In some embodiments, the nozzle 118 may dispense a reagent to fill the recess 116, thus immersing the frontside surface of the substrate 114 in the reagent. In some embodiments, the nozzle may dispense a reagent to be spread uniformly across the frontside surface of the substrate 112. For example, the frontside surface may be covered with a reagent by dispensing the reagent from the nozzle at a flow rate sufficient to cover the frontside surface of the substrate 114 with the reagent while maintaining a rotation rate sufficient to cover the frontside surface with the reagent.
A reagent source 108 is coupled to the process chamber 102 via the incoming fluid line 104 to provide a liquid reagent to the process chamber 102, for example, via the nozzle 118. A heater 120 may be disposed along the fluid line 104 for heating a liquid reagent flowing therethrough prior to use in the process chamber 102. The heater 120 may be disposed at any suitable point along the fluid line 104, for example, as close as possible to the process chamber 102 to minimize heat loss. The heater 120 may be, for example, a point of use heater, or other suitable heating apparatus for heating a reagent to a desired temperature. For example, in some embodiments, the liquid reagent supplied by the reagent source 108 may be at a temperature of between about 15 to about 180 degrees Celsius. In some embodiments, the heater 120 may heat the liquid reagent to a temperature of between about 35 to about 180 degrees Celsius.
A heat exchanger 103 is disposed in-line with the incoming fluid line 104, upstream of the heater 120, to preheat the liquid reagent coming from the reagent source 108 prior to flowing past the heater 120. The heat exchanger 103 generally includes a first side and a second side that are robustly thermally coupled for transferring heat therebetween. The first side of the heat exchanger 103 is coupled in-line with the incoming fluid line 104 such that the liquid reagent supplied by the reagent source 108 flows therethrough. The second side of the heat exchanger 103 is coupled in-line with an effluent line 106 of the process chamber 102 for flowing effluent from the process chamber 102 therethrough.
Heat stored in the effluent coming from the process chamber 102 is transferred to the liquid reagent being provided to the process chamber 102 via the heat exchanger 103. For example, in some embodiments, the effluent discharged from the process chamber 102 after processing may be at a temperature of between about 30 to about 180 degrees Celsius. The heat stored in the effluent may thus be used to pre-heat the liquid reagent provided to the process chamber 102, thereby reducing the power required by the heater 120 to heat the liquid reagent. In some embodiments, pre-heating the liquid reagent using heat transferred from the effluent line 106 may reduce energy consumption by the heater 120 by at least about 20 percent.
The heat exchanger 103 may be any suitable heat exchanger for exchanging heat between two liquids and may be of any suitable size, dependent upon the physical space available. In some embodiments, the heat exchanger 103 may be a non-pressurized system where the effluent may flow through the second side of the heat exchanger under force of gravity. In some embodiments, the heat exchanger 103 may be a pressurized system where the effluent may, for example, collect in a tank, or intermediate reservoir 105, and may be pumped through the second side of the heat exchanger.
Although shown as separate components, in some embodiments, the heat exchanger 103 may be integrated with the heater 120 in a single device that provides both functions as described above. In some embodiments, the heat exchanger 103 may be integrated with the process chamber 102, such that a liquid reagent need only be heated to lesser temperatures prior to delivery to the process chamber through the heat exchanger, which may raise the temperature of the liquid reagent to the desired processing temperature, or which may have an outlet configured to allow attachment of a heater thereto.
The effluent line 106 may be coupled to the base of the process chamber 102. The base of the process chamber 102 need not be horizontal as illustrated in
The incoming fluid line 104 may comprise any suitable materials that facilitate robust heat transfer between the effluent line 106 and a liquid reagent in the fluid line. The effluent line 106 may comprise any suitable materials that facilitate robust heat transfer between the effluent and the fluid line 104. In some embodiments, the materials may have a high thermal conductivity (e.g., greater than or equal to about 300 W/mK). In some embodiments, the thermal conductivity may be lower, e.g., when polymers need to be used due to material compatibility. In some embodiments, the materials may include at least one of copper, steel, stainless steel, galvanized steel, titanium, tungsten, high nickel content alloys, carbon, polymer, silicon, silicon coated metal, aluminum, carbon, quartz, ceramics, and glass, as well as ceramic and/or glass coated materials. In some embodiments, the material of the incoming fluid line 104 may further be selected based on chemical compatibility with a reagent. In some embodiments, the material of the effluent line 106 may further be selected based on chemical compatibility with the disposed effluents.
As discussed above, a portion of the effluent line 106 (i.e., the second side of heat exchanger 103) is thermally coupled to a portion of the incoming fluid line 104 (i.e., the first side of heat exchanger 103). Alternatively, the effluent line 106 may be coiled about the fluid line 104, or thermally coupled to the incoming fluid line 104 in any suitable configuration so as to maximize heat transfer between an effluent flowing in the effluent line 106 and a liquid reagent flowing in the incoming fluid line 104 to the process chamber 102 (e.g., essentially forming a heat exchanger by configuration of the effluent line 106 and the incoming fluid line 104). Alternatively or in combination, a portion of the effluent line 106 may be thermally coupled to the reagent source 108 to facilitate heat transfer to a reagent in the fluid line 104.
The processing system 100 further includes a controller 122 coupled to the process chamber 102 to control the operation thereof and/or to control one or more other components of the processing system 100. The controller 122 generally comprises a central processing unit (CPU), a memory, and support circuits (not shown). The controller 122 controls the process chamber 102 and various chamber components directly or, alternatively, via individual controllers (not shown) associated with each chamber component. In some embodiments, other control elements can be used, such as, for example, industrial controllers without a CPU.
In operation, and initially, a liquid reagent may flow into the incoming fluid line 104 from the reagent source 108 and heated to a desired temperature by the heater 120. The reagent may then flow into the process chamber 102 and through the nozzle 118 to the substrate 114. The reagent reacts and/or becomes contaminated with materials from, or disposed on, the substrate 114 thereby becoming an effluent. The effluent is disposed at the base of the chamber 102 via the effluent line 106. The effluent line 106 transfers heat from the effluent to a liquid reagent in the fluid line 104 via the heat exchanger 103. The liquid reagent, having an elevated temperature from the heat recovered from the effluent, requires less energy from the heater 120 prior to entering the process chamber 102. Thus, the recovered heat from the effluent may reduce energy consumption by the processing system 100, and in some embodiments, the heater 120.
Alternatively, waste heat may be provided by an external waste heat source instead of internally recycling waste heat from disposed effluents as discussed above. An exemplary processing system which relies on an external waste heat source is described below and illustrated in
The waste heat recapture system 301 includes a heat pump 124 coupled to a waste heat source 123 via a waste heat conduit 125 and to the incoming fluid line 104 of the system 300 (or other fluid line that is desired to be heated). The waste heat recapture system 301 uses the waste heat from the waste heat source 123 to pre-heat a reagent flowing through the incoming fluid line 104.
The waste heat source 123 may be any suitable source of waste heat from liquid or gaseous processes or other fab equipment, for example, such as a liquid chemical from a heated bath, a liquid coolant or a gaseous exhaust from a process chamber configured for gaseous processes, process pump stacks, other chamber equipment (such as plasma sources, heaters, hot water exhaust, or the like), a compressed air system, an air separation compressor, air compressors, a gaseous exhaust or a liquid coolant from an abatement device, hot air or a liquid coolant from electrical and/or mechanical equipment, and the like. The heat pump 124 is disposed in-line with a waste heat conduit 125. The waste heat conduit 125 may further couple the waste heat source 123 to an exhaust system 129. The exhaust system 129 may be, for example, an abatement system, or another suitable waste processing system. The waste heat conduit 125 may be typically utilized for transported gaseous effluents exhausted from the waste heat source 123 to the exhaust system 129.
In some embodiments, the heat pump 124 includes a compressor 126 and a heat pump heat exchanger 128. Although shown as separate components, in some embodiments, the heat pump 124 further include (e.g., may be integrated with) the heater 120 or with a different heater. The heat pump may operate similar to a liquid to water geothermic heat pump. Alternatively, the heat pump 124 may be adapted for optionally coupling to a heater, such as the heater 120, should a heater be required.
In some embodiments, the compressor 126 may be disposed in-line with the waste heat conduit 125 between the waste heat source 123 and the heat pump heat exchanger 128. The compressor 126 may be any suitable device for compressing a gaseous effluent. The increased pressure of the gaseous effluent facilitates improved heat transfer in the heat pump heat exchanger 128 by increasing the temperature of the effluent in the waste heat conduit 125.
The heat pump heat exchanger 128 may be any suitable heat exchanger for exchanging heat between the waste effluent and an incoming fluid and may be of any suitable size, dependent upon the physical space available. The heat pump heat exchanger 128 is disposed in-line with the incoming fluid line 104, upstream of the heater 120 (if present), to preheat the reagent coming from the reagent source 108 prior to entering the process chamber 102 (or other location where the heated reagent is to be used). The heat pump heat exchanger 128 generally includes a first side and a second side that are robustly thermally coupled for transferring heat therebetween. The first side of the heat pump heat exchanger 128 is coupled in-line with the incoming fluid line 104 such that the reagent supplied by the reagent source 108 flows therethrough. The second side of the heat pump heat exchanger 128 is coupled in-line with the waste heat conduit 125 for flowing effluent from the waste heat source 123 therethrough.
In operation, the reagent flowing through the incoming fluid line 104 may be heated within the heat pump heat exchanger 128 via thermal transfer of heat from the waste effluent flowing through the waste heat conduit 125. The compression of the waste effluent by the compressor 126 prior to flowing through the heat pump heat exchanger 128 enhances thermal transfer by increasing the temperature of the waste effluent.
Heat stored in the waste effluent coming from the waste heat source 123 is transferred to the reagent being provided to the process chamber 102 via the heat pump heat exchanger 128. For example, in some embodiments, the gaseous effluent discharged from the waste heat source 123 may be at a temperature of between about 30 to about 90 degrees Celsius. The heat stored in the gaseous effluent may thus be used to pre-heat the reagent provided to the process chamber 102, thereby reducing, or eliminating the need for power required by the heater 120 to heat the liquid reagent to the desired temperature. In some embodiments, pre-heating the reagent using heat transferred from the waste heat conduit 125 may reduce energy consumption by the heater 120. In some embodiments, the heat transferred from the waste heat conduit 125 may completely remove the need for further heating by the heater 120.
At least within the heat pump heat exchanger 128, the incoming fluid line 104 and the waste heat conduit 125 may comprise any process-compatible, suitable materials that facilitate robust heat transfer between the waste heat conduit 125 and the fluid in the fluid line. In some embodiments, the materials may have a high thermal conductivity (e.g., greater than or equal to about 300 W/mK). In some embodiments, the thermal conductivity may be lower, e.g., when polymers need to be used due to material compatibility. In some embodiments, the materials may include at least one of copper, steel, stainless steel, galvanized steel, titanium, tungsten, high nickel content alloys, carbon, polymer (such as non-limiting examples of polymethylpentene (PMP, such as TPX®), polyphenylsulfide (PPS), polytetrafluorethylene (PTFE) and other fluorinated or cross linked fluorinated polymers), silicon, silicon coated metal, aluminum, carbon (including crystalline, amorphous, and vitreous graphite), quartz, ceramics, glass, composites, as well as ceramic and/or glass coated materials. In some embodiments, the material of the incoming fluid line 104 and/or the waste heat conduit 125 may further be selected based on chemical compatibility with the respective fluids flowing therein.
As discussed above, a portion of the waste heat conduit 125 (e.g., the second side of heat pump heat exchanger 128) is thermally coupled to a portion of the incoming fluid line 104 (e.g., the first side of heat pump heat exchanger 128). The waste heat conduit 125 may be coiled about the fluid line 104, or may be thermally coupled to the incoming fluid line 104 in any suitable configuration so as to enhance, or maximize, heat transfer between an effluent flowing in the waste heat conduit 125 and a reagent flowing in the incoming fluid line 104 to the process chamber 102. Alternatively or in combination, a portion of the waste heat conduit 125 may be thermally coupled to the reagent source 108 to facilitate heat transfer to a reagent in the fluid line 104.
In some embodiments, and as depicted in
Returning to the process chamber 102, the effluent line 107 may be coupled to the base of the process chamber 102. The base of the process chamber 102 need not be horizontal as illustrated in
The processing system 300 further includes the controller 122 coupled to the process chamber 102 to control the operation thereof and/or to control one or more other components of the processing system 300 and/or the waste recapture system 301. The controller 122 generally comprises a central processing unit (CPU), a memory, and support circuits (not shown). The controller 122 controls the process chamber 102 and various chamber components directly or, alternatively, via individual controllers (not shown) associated with each chamber component. In some embodiments, other control elements can be used, such as, for example, industrial controllers without a CPU.
In operation, a reagent may flow into the incoming fluid line 104 from the reagent source 108 and heated to a desired temperature by the heat pump 124. Effluent exhausted from the waste heat source 123 is pressurized by the compressor 126, thus raising the temperature of the effluent. The pressurized effluent flows through the second side of the heat pump heat exchanger 128 and transfers heat to the reagent disposed in the incoming fluid line 104. The pre-heated reagent may then flow into the process chamber 102 and through the nozzle 118 to the substrate 114. The reagent reacts with and/or becomes contaminated by materials from, or disposed on, the substrate 114, thereby becoming an effluent. The effluent is disposed at the base of the chamber 102 via the effluent line 106 to the exhaust system 110. Optionally, should the reagent require additional heating, the heater 120 may be utilized to further pre-heat the reagent prior to entering the process chamber 102.
Alternative embodiments of the processing system depicted in
Further, the embodiments discussed above for the systems 100 and 300 can be combined into one processing system. Exemplary system combinations are discussed below and illustrated in
For example,
The process system 100 is substantially described above. As depicted in
The semiconductor processing system 450 illustrates one specific example of a secondary system being utilized as part of the waste heat recapture system 301 discussed above. The semiconductor processing system 450 includes a process chamber 452 which may be configured for gaseous processing. The process chamber 452 may include exemplary gaseous processing chambers as discussed above. Further, the process chamber 452 may include any suitable system utilizing gaseous processes, such as compressed air systems, abatement devices, air separation compressors, and the like.
The processing system 450 includes a heat pump 454 disposed in-line with the incoming fluid line 104, upstream of the heater 120 (when present), to preheat the reagent coming from the reagent source 108 prior to flowing into the process chamber 102. The heat pump 454 generally includes a compressor 456 and a heat pump heat exchanger 458. The compressor 456 may be disposed in-line with an exhaust line 160 of the process chamber 452. The compressor 456 may be any suitable compressor for pressurizing a gaseous effluent, such as the compressor 126 discussed above.
The heat exchanger 454 is disposed downstream of the compressor 456, for example, such that a gaseous effluent exhausted from the chamber 152 would enter the compressor 456 prior to entering the heat exchanger 454. The heat exchanger 454 may be substantially similar to the heat pump heat exchanger 128, with the noted exception that the heat exchanger 454 comprises components of both system 100 (a portion of the incoming fluid line 104) and system 450 (a portion of the exhaust line 160). The heat pump heat exchanger 458 includes a first side and a second side that are robustly thermally coupled for transferring heat therebetween. The first side of the heat pump heat exchanger 458 is coupled in-line with the incoming fluid line 104 such that the reagent supplied by the reagent source 108 flows therethrough. The second side of the heat pump heat exchanger 458 is coupled in-line with the effluent line 460 of the process chamber 452 for flowing pressurized gaseous effluent from the process chamber 452 therethrough.
Heat stored in the gaseous effluent or the liquid coolant coming from the process chamber 452 is transferred to the reagent being provided to the process chamber 102 via the heat pump 454. For example, in some embodiments, the gaseous effluent or liquid coolant discharged from the process chamber 452 after processing may be at a temperature of between about 30 to about 300 degrees Celsius. The temperature of the exhausted gaseous effluent or liquid coolant may be increased via pressurization by the compressor 456. The heat stored in the pressurized gaseous effluent may thus be used to pre-heat the reagent provided to the process chamber 102, thereby reducing the power required by the heater 120 to heat the liquid reagent. In some embodiments, pre-heating the liquid reagent using heat transferred from the gaseous effluent line 460 reduces energy consumption by the heater 120. When combined with heat recovered via the heat exchanger 103, the combined heat transferred from the gaseous effluent line 460 and effluent line 106 further reduces energy consumption by the heater 120, and may eliminate the need for the heater 120.
The effluent line 460 may be coupled to the base of the process chamber 102. The effluent exhausted from the process chamber 452 flows through the effluent line 160 to, for example, an effluent system 462 for treatment and/or disposal of the effluent. The effluent system 462 may include, for example, an abatement system or other system suitable for disposal of the effluent.
The effluent line 460 may comprise any suitable materials that facilitate robust heat transfer between the gaseous effluent and the fluid line 104. In some embodiments, the materials may have a high thermal conductivity (e.g., greater than or equal to about 300 W/mK). In other embodiments the thermal conductivity may be lower, e.g. when polymers need to be used due to material compatibility. In some embodiments, the materials include those materials utilized with exhaust line 106. In some embodiments, the material of the effluent line 460 may further be selected based on chemical compatibility with a gaseous process, for example, such as an etch process or other such process which may produce corrosive effluents.
As discussed above, a portion of the effluent line 460 (e.g., the second side of heat exchanger 158) is thermally coupled to a portion of the incoming fluid line 104 (e.g., the first side of heat pump heat exchanger 458). For example, the effluent line 460 may be coiled about the fluid line 104, or thermally coupled to the incoming fluid line 104 in any suitable configuration so as to maximize heat transfer between an effluent flowing in the effluent line 460 and a reagent flowing in the incoming fluid line 104 to the process chamber 102. Alternatively or in combination, a portion of the effluent line 460 may be thermally coupled to the reagent source 108 to facilitate heat transfer to a reagent in the fluid line 104.
The processing system 450 further includes a controller 464 coupled to the process chamber 452 to control the operation thereof and/or to control one or more other components of the processing system 450. The controller 464 is substantially equivalent to the controller 122, and controls the process chamber 102 and various chamber components directly or, alternatively, via individual controllers (not shown) associated with each chamber component. Further, the processing system 400 may further include a central controller (not shown) for controlling the components of each processing system (e.g., processing systems 100, 450) directly or, alternatively via individual controllers, such as controllers 122, 464 associated with each system.
In operation, a reagent may flow into the incoming fluid line 104 from the reagent source 108. In some embodiments, the reagent may be initially heated to a desired temperature by the heater 120. The reagent may then flow into the process chamber 102 and through the nozzle 118 to the substrate 114. The reagent reacts and/or becomes contaminated with materials from, or disposed on, the substrate 114 thereby becoming an effluent (e.g., a first effluent). The effluent is disposed at the base of the chamber 102 via the effluent line 106. The effluent line 106 transfers heat from the effluent to a reagent in the fluid line 104 via the heat exchanger 103. Similarly, a second effluent is exhausted from the chamber 452 via the effluent line 460 and is routed to the heat pump 454. The second effluent is pressurized by the compressor 456, and the effluent line 460 transfers heat from the pressurized second effluent to the liquid reagent in the fluid line 104 via the heat pump heat exchanger 458. The reagent, having an elevated temperature from the heat recovered from both the first and second effluents, requires less energy, if any, from the heater 120 prior to entering the process chamber 102. Thus, the recovered heat from the effluent may reduce energy consumption by the processing system 400.
Alternative embodiments of the processing system 400 are possible. For example, the processing system 100 may optionally not include the heat exchanger 103 and may be solely pre-heated by the heat pump 454 of the processing system 150. In another alternative embodiment, the heater 120 may be optionally excluded if the waste heat recovery system (e.g., the heat exchanger 103 and heat pump 454) are sufficient to pre-heat the incoming fluid to operating temperature. In some embodiments, the heat exchanger 103 may be located downstream of the heat pump 154.
Further alternatives of the processing system 400 are possible. For example, both the processing chambers 102, 452 may be wet benches, or alternatively, both may be configured for gaseous processes.
The heat exchange apparatus 502 is illustrated in detail in
In operation, the processing system 500 is substantially similar to the operation of the processing system 400 as discussed above. However, and as noted above, waste heat from the effluents of each system 100, 450 is thermally coupled to an incoming reagent from the reagent source 108 along a common portion of the incoming fluid line 104, where the common portion of the incoming fluid line 104 forms the first side of the heat exchange apparatus 502. Accordingly, the waste heat from both systems 100, 450 may be transferred to an incoming reagent simultaneously via flowing effluent through respective heat exchanger conduits 503, 558. Alternatively, and depending on the duty cycles of each processing system, waste heat may be thermally transferred to an incoming reagent by alternating use of each heat exchange conduit 503, 558. Waste heat may be thermally transferred to an incoming reagent by any suitable scheme as dictated by the duty cycles of each processing system 100, 450. For example, if the duty cycle of the processing system 450 is twice that of the system 100, the heat exchange conduit 358 may be utilized to pre-heat an incoming reagent from the reagent source 108 about twice as often as the heat exchange conduit 303. Further, any of the operation schemes discussed above for system 500 may be utilized with the system 400.
Alternative embodiments of the processing system 500 are possible. For example, both the processing chambers 102, 452 may be wet benches. In embodiments, where the reagents supplied to each wet bench are chemically compatible, the exhaust lines 106, 460 may feed into a common line (not shown). The common line, for example, may be utilized as the second side of a common heat exchanger, which replaces the individual second sides of the heat exchange conduits 503, 558. Further, the common line may feed into a common exhaust system, which replaces the individual exhaust systems 110, 462. Other alternatives embodiments are possible. For example, both process chambers 102, 452 may be configured for gaseous processes. In embodiments, where gaseous reagents supplied to each chamber are chemically compatible, the system 500 may be configured in a similar configuration as discussed above. In addition, in any of embodiments disclosed herein, where waste heat effluents from different sources are compatible, they may be aggregated prior to entering a common heat pump.
Embodiments of processing systems disclosed above have generally been discussed in the context of pre-heating a reagent prior to entering a process chamber. However, other apparatus may benefit from the present invention. For example, an ion exchanger such as one utilized for the generation of ultra-pure water (e.g., a liquid reagent) may benefit from the present invention. For example, apparatus as discussed above may utilize waste heat from disposed effluents to pre-heat regeneration water prior to flowing the regeneration water through an ion exchanger. For example, the regeneration water may be utilized to clean or regenerate the ion exchanger by removing ionic species collected in the exchanger. In some embodiments, the apparatus as discussed above may be used to recapture waste heat to drive a halopolymer (e.g., polymers having halogen atoms incorporated therein, such as attached to their backbone) sub atmospheric acid distillation/purification system and or resin based concentrator to recover waste acids (such as HF, HCL, HNO3, or other waste chemicals) and return them to be used in a process as reagents or cleaning solutions.
Methods for processing a substrate are described below. The inventive methods may be utilized in the inventive processing systems discussed above, however, other processing systems may benefit from the inventive methods as well.
At 604, the liquid reagent may be pre-heated by the heat exchanger 103. For example, heat may be recovered from an effluent by diffusing into the material of the effluent line 106. Such material may include any material having high thermal conductivity, such as discussed above. From the effluent line 106, heat may diffuse into the fluid line 104 and ultimately to a reagent flowing along, or statically disposed, along the portion of the fluid line 104 thermally coupled to the effluent line 106.
The liquid reagent may include, for example, water, ultra-pure water, de-ionized water, or the like, which may be utilized, for example, to rinse the substrate 114 during a wet chemical etch or a wet chemical cleaning process. Further, the liquid reagent may include any suitable chemical and/or chemical solution that requires heating prior to use in the process chamber 102. For example, suitable chemicals and/or chemical solutions may include chemicals used in wet strip or wet etch process, such as hydrochloric acid (HCl), hydrofluoric acid (HF), ammonium hydroxide (NH4OH), hydrogen peroxide (H2O2), phosphoric acid (H3PO4), or sulfuric acid (H2SO4), or the like. Although the above example relates to wet etch, wet strip, and wet chemical cleaning processes, any other silicon processing that utilizes liquid reagents as disclosed herein.
The temperature of the liquid reagent prior to heat transfer may be about room temperature, or between about 15 to about 180 degrees Celsius. Heat recovered from the effluent may pre-heat the liquid reagent to a temperature between about 30 to about 180 degrees Celsius.
At 606, the pre-heated liquid reagent to a desired temperature using, for example, the heater 120. For example, the heater 120 may heat the reagent to up to about 180 degrees Celsius, or between about 35 to about 180 degrees Celsius. Upon heating the liquid reagent to a desired temperature, the method 600 generally ends by flowing the heated liquid reagent to the process chamber 102.
Alternatively,
At 804, a first effluent is exhausted from the waste heat source (e.g., process chamber 452). The first effluent may be in a gaseous form, and may be for example, a process gas or gaseous byproduct of a semiconductor process, such as an etch process, deposition process, or any suitable process resulting in an effluent from which waste heat can be recovered. Alternatively, or in combination, waste heat from other sources of the processing system may be captured, such as from compressed air systems, air separation compressors, pumps, electrical and/or mechanical equipment, abatement devices, or the like. Alternatively, the waste heat might be captured by a liquid coolant.
Optionally, at 806, the first effluent may be pressurized. For example, the compressor 456 may compress the first effluent, thus increasing the temperature of the first effluent. The increase in temperature by pressurization may facilitate improved heat transfer between the first effluent and a reagent to be heated. Alternatively, the first effluent may be routed through the heat pump to transfer heat to the heat transfer fluid, which is then pressurized and pumped through the heat pump to the portion used for heating the reagent in the fluid line.
At 808, a reagent may be pre-heated by transferring waste heat from the first effluent to the reagent. For example, the reagent may be statically disposed in, or flowing through, a portion of the incoming fluid line 104 (e.g., the first side of the heat pump heat exchanger 458, or coupled to a portion of the heat pump 454) coupled to a process chamber (e.g., process chamber 102). The reagent may be pre-heated by transferring waste heat from the first effluent flowing through, or statically disposed in, a portion of the exhaust line 460 (e.g., the second side of the heat pump heat exchanger 458, or coupled to a portion of the heat pump 454).
The reagent may include, for example, water, ultra-pure water, de-ionized water, or the like, which may be utilized, for example, to rinse the substrate 114 during a wet chemical etch or a wet chemical cleaning process. Further, the liquid reagent may include any suitable chemical and/or chemical solution that requires heating prior to use in the process chamber 102. For example, suitable chemicals and/or chemical solutions may include acids, bases and/or solvents used in wet strip or wet etch process or wet cleaning processes, such as hydrochloric acid (HCl), hydrofluoric acid (HF), ammonium hydroxide (NH4OH), hydrogen peroxide (H2O2), phosphoric acid (H3PO4), or sulfuric acid (H2SO4), or the like. Although the above example relates to wet etch, wet strip, and wet chemical cleaning processes, the present invention is applicable to other substrate processing that utilizes liquid or gaseous reagents as disclosed herein.
In some embodiments, for illustration, the temperature of the reagent prior to heat transfer may be about room temperature, or between about 15 to about 30 degrees Celsius. Waste heat recovered from the effluent may pre-heat the reagent to a temperature between about 30 to about 180 degrees Celsius.
In some embodiments, the heated reagent may be then flowed to the process chamber for use therein, as shown at 814. Upon providing the heated reagent to the process chamber 102, or to some other destination, the method 800 generally ends. However, additional embodiments of the method 800 are possible. For example, should waste heat from the pressurized first effluent not sufficiently pre-heat the reagent to processing temperatures, the heater 120 may be utilized to further pre-heat the reagent to a desired processing temperature.
Further, waste heat may be recovered from others sources and utilized to pre-heat the reagent in combination with the waste heat recovered from the first effluent. For example, after processing in the process chamber 102, the reagent may be converted to a second effluent that is exhausted from the process chamber 102. For example, the second effluent may include the reagent, as well as byproducts materials, such as materials from a substrate being processed. The second effluent, partially formed from the heated reagent, may have waste heat which can be recovered.
In some embodiments, as shown at 810 in phantom, the second effluent may be exhausted from the process chamber 102. The second effluent may have waste heat that can be recovered to pre-heat the reagent to be used in the process chamber 102.
As such, at 812, the reagent may be further pre-heated for use in the process chamber 102 by transferring waste heat from the second effluent to the reagent. In some embodiments, the reagent may be pre-heated by transferring waste heat from the second effluent through a heat pump. In some embodiments, the reagent may be pre-heated by transferring waste heat from the second effluent through a heat exchanger. In some embodiments, the reagent may be statically disposed, or flowing through, a portion of the incoming fluid line 104 (e.g., the first side of heat exchanger 103) coupled to a process chamber (e.g., process chamber 102). The reagent may be pre-heated by transferring waste heat from the second effluent flowing through, or statically disposed in, a portion of the exhaust line 106 (e.g., the second side of the heat exchanger 103).
The heat exchanger 103 may be utilized for pre-heating the reagent in addition to, in alternation with, or in place of the heat pump 458. As discussed above, the heat exchanger 103 may be located downstream of (not shown), upstream of (
Waste heat from the second effluent need not be recycled to heat a reagent entered the same process chamber (e.g., process chamber 102) from which the second effluent was generated. For example, waste heat from the second effluent may be utilized to pre-heat a reagent for use in a different process chamber (similar to
Thus, methods and apparatus for recovering heat from disposed effluents have been disclosed herein. The inventive methods and apparatus advantageously facilitate reduced energy consumption of a semiconductor or other processing system by utilizing heat from disposed effluents to pre-heat reagents entering the processing system. The reduction of heat in the disposed effluents is further advantageous for subsequent processing of the disposed effluents, such as abatement.
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof.
This application claims benefit of U.S. provisional application Ser. No. 61/105,949, filed Oct. 16, 2008, and U.S. provisional application Ser. No. 61/229,812, filed Jul. 30, 2009, each of which are herein incorporated by reference.
Number | Date | Country | |
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61105949 | Oct 2008 | US | |
61229812 | Jul 2009 | US |