Heated valve for semiconductor processing tools

Abstract

One example provides a heated valve for a semiconductor processing tool. The heated valve comprises a valve body comprising an internal side, and a heater assembly configured to heat at least a portion of the internal side of the valve body. The heater assembly comprises a heater including an electrical insulator and a resistive trace embedded within the electrical insulator. The heater is configured to output different watt densities as a function of a location on the heater.

Description

Docket No. LRC25304PPCTHEATED VALVE FOR SEMICONDUCTOR PROCESSING TOOLSBACKGROUND

[0001] Various valves, such as throttle valves, can be used in a semiconductor processing tool to regulate gas flow. For example, one or more valves can be used in an exhaust system of a semiconductor processing tool to regulate exhaust flow from a processing chamber. Likewise, one or more valves can be used in a processing chemical delivery system to control processing chemical flows into, and / or regulate pressures within, the processing chamber.SUMMARY

[0002] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure.

[0003] One example provides a heated valve for a semiconductor processing tool. The heated valve comprises a valve body comprising an internal side and a heater assembly configured to heat at least a portion of the internal side of the valve body. The heater assembly comprises a heater including an electrical insulator and a resistive trace embedded within the electrical insulator. The heater is configured to output different watt densities as a function of a location on the heater.

[0004] In some such examples, the heater assembly alternatively or additionally comprises a clamping structure to hold the heater assembly to the valve body.

[0005] In some such examples, the heater assembly alternatively or additionally comprises a thermally conductive elastomer located between and in contact with the heater and the clamping structure.

[0006] In some such examples, the heater assembly alternatively or additionally comprises a thermal insulator arranged externally to the clamping structure.

[0007] In some such examples, the heater assembly alternatively or additionally comprises a thermal interface material arranged between the heater and an external side of the valve body.Docket No. LRC25304PPCT

[0008] In some such examples, the valve body alternatively or additionally comprises a channel on an external side. In such examples, the heater is arranged within the channel.

[0009] In some such examples, the electrical insulator comprises a polyimide, and the resistive trace comprises a nickel-containing metal trace.

[0010] In some such examples, the heater assembly is alternatively or additionally a first heater assembly configured to heat at least a first portion of the internal side of the valve body. In such examples, the heated valve further comprises a second heater assembly configured to heat at least a second portion of the internal side of the valve body.

[0011] Another example provides a semiconductor processing tool comprising a gas line and a heated valve arranged along the gas line. The heated valve comprises a valve body comprising an internal side and a heater assembly configured to heat at least a portion of the internal side of the valve body. The heater assembly comprises a heater including an electrical insulator and a resistive trace embedded within the electrical insulator. The heater is configured to output different watt densities as a function of a location on the heater.

[0012] In some such examples, the gas line alternatively or additionally comprises an exhaust line.

[0013] In some such examples, the heater assembly alternatively or additionally comprises a clamping structure to hold the heater assembly to the valve body.

[0014] In some such examples, the heater assembly alternatively or additionally comprises a thermally conductive elastomer located between and in contact with the heater and the clamping structure.

[0015] In some such examples, the heater assembly alternatively or additionally comprises a thermal insulator arranged externally to the clamping structure.

[0016] In some such examples, the valve body comprises a channel on an external side. In such examples, the clamping structure is alternatively or additionally configured to hold the heater within the channel.

[0017] In some such examples, the heater assembly alternatively or additionally comprises a thermal interface material located between the heater and an external side of the valve body.

[0018] In some such examples, the electrical insulator comprises a polyimide, and the resistive trace comprises a nickel-containing metal trace.Docket No. LRC25304PPCT

[0019] In some such examples, the heater assembly is alternatively or additionally a first heater assembly configured to heat at least a first portion of the internal side of the valve body. In such examples, the heated valve alternatively or additionally comprises a second heater assembly configured to heat at least a second portion of the internal side of the valve body.

[0020] Another example provides a heater assembly for a heated valve. The heater assembly comprises a heater including an electrical insulator and a resistive trace embedded within the electrical insulator. The heater assembly further comprises a clamping structure to hold the heater assembly to a valve body of the heated valve. The heater assembly additionally comprises a thermally conductive elastomer located between the heater and the clamping structure.

[0021] In some such examples, the heater is configured to output different watt densities as a function of a location on the heater.

[0022] In some such examples, the electrical insulator comprises a polyimide, and the resistive trace comprises a nickel-containing metal trace.BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1 schematically depicts an example semiconductor processing tool utilizing heated valves.

[0024] FIGS. 2A and 2B, respectively, show a valve with cartridge heaters and a corresponding graph illustrating temperature nonuniformity.

[0025] FIGS. 3 A, 3B, and 3C schematically depict various views of an example heated valve.

[0026] FIG. 4 schematically depicts a side view of another example heated valve.

[0027] FIG. 5 schematically depicts an example heater for use with a heated valve.

[0028] FIGS. 6 and 7 show thermal simulations using the heater of FIG. 5 with uniform watt density and varying watt densities, respectfully.

[0029] FIG. 8 schematically depicts a plan view of an example heated valve and illustrates thermocouple locations used in temperature uniformity experiments.

[0030] FIGS. 9 and 10 show graphs illustrating results of temperature uniformity experiments for the heated valve of FIG. 8.Docket No. LRC25304PPCT

[0031] FIG. 11 schematically depicts an exploded view of another example heater assembly.DETAILED DESCRIPTION

[0032] The term “clamping structure” may generally represent a physical component of a heater assembly configured to hold the heater assembly to a valve body.

[0033] The term “crosswise direction” may generally represent a path within a plane perpendicular to an axis or length of a heated valve.

[0034] The term “deposition” and variants thereof may generally represent a process in which a film is formed on a substrate from one or more precursor chemicals. Examples of deposition processes include chemical vapor deposition (CVD) and atomic layer deposition (ALD).

[0035] The term “electrical insulator” may generally represent a material with relatively low conductivity such that sufficient electrical current does not flow.

[0036] The term “etch” and variants thereof may generally represent a chemical and / or physical process by which material is removed from a substrate.

[0037] The term “external” and variants thereof may generally represent a location of an element that is relatively farther from a center of a heated valve. For example, a side of a valve body that is farther from the center of the heated valve than the valve body is referred to as the external side.

[0038] The term “gas line” may generally represent a physical pathway comprising pipes, valves, and other components for moving gas to or from a processing chamber of a semiconductor processing tool.

[0039] The term “heat” generally represents thermal energy.

[0040] The term “heated valve” may generally represent a physical structure disposed along a gas line and used to control air flow into and / or out of a processing chamber. Further, the heated valve comprises mechanisms to provide thermal energy to a side of a valve body that faces the air flow within the gas line.

[0041] The term “heater” may generally represent electrical and mechanical components configured to generate thermal energy.

[0042] The term “heater assembly” may generally represent a physical stack of layers including a heater for distribution of thermal energy to an internal side of a valve body.Docket No. LRC25304PPCT

[0043] The term “internal” and variants thereof may generally represent a location of an element that is relatively closer to a center of a heated valve. For example, a side of a valve body that is closer to the center than the valve body of the heated valve is referred to as the internal side.

[0044] The term “nickel-containing” may generally represent a material that comprises one or more nickel species.

[0045] The term “polyimide” may generally represent a polymer containing imide groups.

[0046] The term “processing chamber” may generally represent an enclosure in which chemical and / or physical processes are performed on substrates.

[0047] The term “resistive trace” may generally represent a pathway of electrical material in a heater that consumes electrical energy to thereby generate heat.

[0048] The term “semiconductor processing tool” may generally represent a machine including one or more processing chambers and related processing systems that are configured to enable processing to be carried out in the processing chamber.

[0049] The term “substrate” may generally represent any object on which chemical and / or physical processes are performed in a processing chamber.

[0050] The term “thermally conductive elastomer” may generally represent a polymer having both viscosity and elasticity, along with weak intermolecular forces. Further, the polymer is configured to allow the flow of heat.

[0051] The term “thermal insulator” may generally represent a component of a heater assembly comprising material that has relatively weak heat conductance.

[0052] The term “thermal interface material” may generally represent a layer of a heater assembly that has relatively high heat conductance.

[0053] The term "valve body" may generally represent a physical mass of a heated valve. The valve body comprises an internal side and an external side.

[0054] The term "valve flapper" may generally represent a rotatable component of a heated valve that changes an area for air flow in a gas line.

[0055] The term “watt density” may generally represent electrical energy per a unit of time per a unit of area.

[0056] As mentioned above, valves can be used in a variety of locations in a semiconductor processing tool, such as in an etching tool or a deposition tool. Some valves can be located along flow paths, or gas lines, that conduct condensable gases. Such gases can condense into liquid and / or solid form on exposed internal surfacesDocket No. LRC25304PPCTwithin a gas line. As an example, a throttle valve or other suitable valve can be used on an exhaust line through which exhaust from a processing chamber is conducted to help control pressure in a processing chamber on the semiconductor processing tool. However, exposure to such condensable gases can lead to deposits forming on an internal side of the valve. Such deposits can build up over time and cause the eventual failure of the valve.

[0057] To avoid the formation of such deposits, a valve can be heated to raise temperatures on the internal side of the valve. Current heated valves often use cartridge heaters that typically are inserted into machined spaces within a valve body. However, the cartridge heaters can cause relatively high temperature nonuniformities at various locations on the internal side of the valve body. To ensure that the internal side exposed to a condensable gas is sufficiently heated, the cartridge heaters may be set to a substantially higher temperature than the condensation temperature of the condensable gas due to such nonuniformities. Such temperatures can cause degradation of coatings and / or components of the valve, thereby shortening the life of the valve. Additionally, adjacent components to the valve, such as O-rings and / or insulation, also can be damaged by such relatively high temperatures.

[0058] Accordingly, examples are disclosed that relate to utilizing a heater configured to output different watt densities as a function of a location on the heater. For example, a heated valve utilizes a heater assembly comprising the heater to heat at least a portion of an internal side of a valve body. As the watt density at a location on the heater correlates to thermal energy generated at the location, the heater can be configured to conform to a nonuniform thermal mass of the valve body. Briefly, the heater includes an electrical insulator and a resistive trace embedded within the electrical insulator. The resistive trace enables the watt density to vary for different locations on the heater.

[0059] Further, the heater assembly can comprise one or more additional layers to help spread thermal distribution to the internal side of the valve body. As examples, a clamping structure can be used to hold the heater assembly to the valve body. A thermally conductive elastomer, when included, is in contact with the heater and the clamping structure. Further, a thermal insulator, when included, can be arranged externally to the clamping structure.

[0060] Prior to discussing these examples in detail, FIG. 1 shows a schematic view of an example semiconductor processing tool 100. Here, the semiconductorDocket No. LRC25304PPCTprocessing tool 100 is in the form of a deposition tool comprising a first processing station 102 A and a second processing station 102B positioned within a processing chamber 104. The semiconductor processing tool 100 further may comprise additional stations not shown in FIG. 1. In other examples, a semiconductor processing tool can be in the form of an etching tool.

[0061] The first processing station 102A comprises a first substrate holder 106A positioned within a first well 108 A of the processing chamber 104. The first substrate holder 106A supports a first substrate 110A during a deposition process. The first processing station 102A further comprises a first gas outlet 112A in fluid connection with a gas delivery system 114. The gas delivery system 114 is configured to provide one or more process gases, purge gas(es), and / or another suitable gas. A first valve 116A in the form of a heated valve is arranged along a first gas line between the gas delivery system 114 and the first gas outlet 112A to control the flow of gas(es) to the first gas outlet 112 A.

[0062] Likewise, the second processing station 102B comprises a second substrate holder 106B positioned within a second well 108B of the processing chamber 104. The second substrate holder 106B supports a second substrate HOB during the deposition process. The second processing station 102B further comprises a second gas outlet 112B in fluid connection with the gas delivery system 114 through a second valve 116B.

[0063] The semiconductor processing tool 100 also comprises a vacuum system 118 to evacuate the processing chamber 104. The vacuum system 118 includes a vacuum line 120 configured to carry a flow of exhaust from the processing chamber 104. The exhaust may comprise unreacted precursor, deposition byproducts, and / or inert gases used in the deposition process. The vacuum system 118 also comprises an exhaust valve 122 arranged along the vacuum line 120 and one or more pumps 124 to control flow of the exhaust. Here, the vacuum system 118 is in fluid connection to the first processing station 102 A through a first exhaust port 126 A. Similarly, the second processing station 102B is in fluid connection with the vacuum system 118 through a second exhaust port 126B.

[0064] Here, the first valve 116A, the second valve 116B, and the exhaust valve 122 are in the form of heated valves. Specifically, a heated valve comprises a valve body and a heater assembly attached to the valve body. As will be discussed in more detail with reference to FIGS. 3A, 3B, and 3C, the heater assembly utilizes a heaterDocket No. LRC25304PPCTconfigured to output different watt densities as a function of location on the heater to heat at least a portion of an internal side of the valve body. This helps the resulting temperature of the internal side of the valve body to be more uniform compared to a valve utilizing cartridge heaters. In various examples, the heated valve can include a butterfly valve, a gate valve, or another suitable valve.

[0065] The semiconductor processing tool 100 further comprises a controller 128 configured to control various aspects of the semiconductor processing tool 100. For example, the controller 128 can control the vacuum system 118, the first and second substrate holders 106A, 106B, the gas delivery system 114, the first and second valves 116A, 116B, the exhaust valve 122, and / or other suitable components of the semiconductor processing tool 100. As a specific example, the controller 128 may control the first valve 116A, the second valve 116B, the exhaust valve 122, and the one or more pumps 124 to control pressure and / or gas composition inside the processing chamber 104. FIG. 1 is illustrative. In other examples, the semiconductor processing tool 100 can comprise other components not depicted, such as substrate holder heaters, gas line heaters, substrate transfer robots, load locks, and / or any other suitable components. In further example, a semiconductor processing tool can have another configuration.

[0066] FIGS. 2 A and 2B respectfully illustrate a plan view of an example valve 200 with cartridge heaters 202 and a corresponding graph illustrated measured temperature versus time. In FIG. 2A, the cartridge heaters 202 are embedded into a valve body 204 of the valve 200. Further, a valve flapper 206 is contained within an internal side of the valve body 204. The valve flapper 206 is selectively controllable to control gas flow through the valve 200.

[0067] Thermocouples i3, i4, i5, and i6 are located on the internal side of the valve body 204 which is heated by the cartridge heaters 202. In FIG. 2B, measured temperature for the thermocouples i3, i4, i5 and i6 are depicted over time for a ramp-up stage 208, a gas flow introduction stage 210, and a setpoint lowering stage 212. As can be seen, the measured temperature of these locations on the internal side varied by over 35 degrees Celsius.

[0068] Accordingly, to help reduce temperature variation on an internal side of a valve body, a heater assembly comprises a heater configured to output different watt densities as a function of location on the heater. FIGS. 3 A, 3B, and 3C schematically depict an example heated valve 300 utilizing such heater assemblies. The heated valveDocket No. LRC25304PPCT300 can be in the form of suitable throttle valves for suitable semiconductor processing tools. For example, the heated valve 300 can be used for the first valve 116A, the second valve 116B, and / or the exhaust valve 122 of FIG. 1.

[0069] The heated valve 300 comprises a valve body 302 with an internal side 304 and an external side 306. As depicted, the internal side 304 faces a valve flapper 308 contained within the valve body 302. Further, a first heater assembly 310 and a second heater assembly 312 are configured to heat at least respective portions of the internal side 304. In some examples, the heat further transfers to the valve flapper 308. Briefly, FIG. 3A illustrates a cutaway plan view of the heated valve 300. FIG. 3B illustrates an exploded view of the first heater assembly 310 in relation to a portion of the valve body 302. Additionally, FIG. 3C illustrates a section view taken along 3C-3C of FIG. 3B through the first heater assembly 310.

[0070] The first heater assembly 310 comprises a first heater 314 for heating at least a first portion 304A of the internal side. Further, a length of the first heater 314 is arranged along a crosswise direction of the valve body 302. The term “crosswise” as used with reference to the orientation of the length of the first heater 314 generally indicates a transverse relationship to the valve body 302 that can be orthogonal or not orthogonal. In the current example, the crosswise direction of the valve body 302 comprises an external circumference. In other examples, a heater can be arranged in another suitable manner relative to a valve body. In further examples, a heater may have another suitable aspect ratio than depicted in FIGS. 3A-3C.

[0071] The first heater 314 comprises an electrical insulator 316 to provide electrical isolation from the valve body 302. Additionally, the electrical insulator 316 can provide mechanical protection for the first heater 314. In some examples, the electrical insulator 316 can comprise a polyimide. In other examples, the electrical insulator 316 can comprise another suitable material. Such a configuration enables the first heater 314 to conform to a contour of the external side 306, and thereby helps to spread out heat distribution through thermal contact. The first heater 314 also comprises a resistive trace 318 embedded in the electrical insulator 316. Electrical energy consumed along the resistive trace 318 can be converted to thermal energy. As such, the resistive trace 318 enables the first heater 314 to output different watt densities as a function of a location on the first heater 314. In some examples, the resistive trace 318 can include a suitable nickel-containing metal trace, such as an Inconel trace, for example.Docket No. LRC25304PPCT

[0072] As a specific example, different sections along a length of the first heater 314 can output different watt densities, as will be discussed in more detail with reference to FIGS. 5-7. Thus, the first heater 314 can provide heat in a nonuniform manner that can conform to the nonuniform thermal mass of the valve body 302. This can help to reduce temperature variation on the internal side 304 during operation of the heated valve 300.

[0073] Additionally, the first heater assembly 310 comprises a clamping structure 320 configured to hold the first heater assembly 310 to the valve body 302. As a specific example, the clamping structure 320 can hold the first heater assembly 310 such that the first heater 314 is in contact with the external side 306 for heat transfer and distribution to the valve body 302. In the depicted example, the clamping structure 320 includes a strap 320A and screws 320B. The strap 320A can include aluminum, stainless steel, or another suitable material. In other examples, a clamping structure can have another configuration. As can be seen in FIG. 3C, a channel 322 can be formed in a portion of the external side 306 to accommodate at least the first heater 314. As such, the clamping structure 320 is configured to hold the first heater assembly 310 such that the first heater 314 is arranged within the channel 322 of the valve body 302. In other examples, a heater assembly can be incorporated into a valve body in another suitable manner.

[0074] A thermally conductive elastomer 324 is arranged between the first heater 314 and the clamping structure 320 in the first heater assembly 310. In such a configuration, the thermally conductive elastomer 324 can be in contact with both the first heater 314 and the clamping structure 320, and thereby helps to handle thermal mismatch (e.g., different coefficients of thermal expansion) therebetween. This can help to prevent fractures and / or warpage within the first heater assembly 310, along with helping to spread out the heat generated by the first heater 314. Additionally, the thermally conductive elastomer 324 can help to add local compliance so that substantially all areas of the first heater 314 impinge upon a corresponding portion of the external side 306 of the valve body 302. Such a configuration provides the benefit of greater thermal transfer efficiency of the first heater assembly 310. Further, the thermally conductive elastomer 324 can enable substantially all local areas of the first heater 314 to sink heat into the external side 306 of the valve body 302 and thus, help to prevent melting of the resistive trace 318. The term “substantially” as used with reference to the area of the heater that impinges upon the valve body indicates sufficientDocket No. LRC25304PPCTimpingement of the first heater 314 with the valve body 302 to avoid melting of the resistive trace 318. Therefore, the thermally conductive elastomer 324 can help to relatively increase reliability of the first heater 314 compared to a heater assembly without a thermally conductive elastomer. As a specific example, the thermally conductive elastomer 324 can act similar to a bunch of tiny springs that hold the first heater 314 in contact with the valve body 302 at corresponding tiny locations for transferring heat. Such a configuration can help to prevent locations with no contact between the first heater 314 and the valve body 302. Such locations otherwise could possibly result in the first heater 314 overheating and causing a failure. In various examples, the thermally conductive elastomer 324 can comprise suitable elastomeric thermally conductive materials (e.g., conductive silicone) and / or suitable non-elastomeric thermally conductive materials (e.g., nickel or aluminum spheres). In other examples, the thermally conductive elastomer 324 may be omitted. Additionally, the first heater assembly 310 comprises a thermal insulator 326 arranged externally to the clamping structure 320. The thermal insulator 326 is configured to be attached to the clamping structure 320, for example, by utilizing the screws 320B. Alternatively or additionally, the thermal insulator 326 can be attached to the clamping structure 320 utilizing adhesive, a snapping structure, or in another suitable manner. The thermal insulator 326 can comprise polyether ether ketone (PEEK) or another suitable thermally insulating material.

[0075] The thermal insulator 326, the clamping structure 320, the thermally conductive elastomer 324, and the first heater 314 form a stack-up of layers of the first heater assembly 310. This stack-up of layers helps to provide good contact between adjacent layers as well as between the first heater 314 and the external side 306 of the valve body 302 along respective area dimensions. For example, such good contact is made without air gaps between the corresponding adjacent layers. In further examples, the first heater assembly 310 can comprise other suitable components.

[0076] Likewise, the second heater assembly 312 comprises a second heater for heating at least a second portion 304B of the internal side. Further, the second heater assembly 312 comprises a thermally conductive elastomer, a clamping structure, and a thermal insulator. Therefore, the first heater assembly 310 and the second heater assembly 312 heat at least the internal side 304 in a more uniform manner than comparable valves utilizing cartridge heaters. While the heated valve 300 has two heater assemblies, in other examples, a heated valve may have a single heater assemblyDocket No. LRC25304PPCTaccording to the present disclosure, or three or more heater assemblies. FIGS. 3A, 3B, and 3C are illustrative. In other examples, a heated valve may have another suitable configuration.

[0077] FIG. 4 schematically depicts another example heated valve 400 according to the present disclosure. The heated valve 400 can be used in suitable semiconductor processing tools, such as the semiconductor processing tool 100, for example. Similar to the heated valve 300, the heated valve 400 comprises a valve body 402 and two heater assemblies. Particularly, a first heater assembly 404 is configured to heat at least a first portion 406A of an internal side of the valve body 402. Additionally, the first heater assembly 404 comprises a clamping structure 408, a thermally conductive elastomer 410, and a heater including an electrical insulator 412 and a resistive trace 414 embedded in the electrical insulator 412. Further, the heater is configured to output different watt densities as a function of a location on the heater. Likewise, a second heater assembly 416 is configured to heat at least a second portion 406B of the internal side of the valve body 402.

[0078] In the example of FIG. 4, the first heater assembly 404 additionally comprises a mount sheet 418 bonded to the electrical insulator 412. The mount sheet 418 can comprise stainless steel or another suitable material. In such a configuration, the mount sheet 418 can help shape the heater to conform to a shape of an external side of the valve body 402. This can help the heater and the valve body 402 to be in contact along a length of the heater, which helps to spread out distributing heat from the heater. Likewise, the second heater assembly 416 also comprises a corresponding mount sheet.

[0079] An example heated valve 400 has been found in experiments to result in about 1 / 4 of the differential temperature on the internal side 406A, 406B of the valve body 402 when compared with similar valves utilizing cartridge heaters (e.g., the valve of FIG. 2A). FIG. 4 is illustrative. In other examples, a heated valve may have a single heater assembly according to the present disclosure, or three or more heater assemblies.

[0080] FIG. 5 schematically depicts an example heater 500 for a heated valve. For example, the heater 500 can be used in the heated valve 300 and / or the heated valve 400. Additionally, FIGS. 6 and 7 show results of a thermal simulation 600 and a thermal simulation 700, respectively, using the heater 500. Such thermal simulations can help to optimize watt density as a function of location on the heater 500. In such a manner, the watt density can be optimized to a thermal mass of a valve body of a heated valve,Docket No. LRC25304PPCTfor example, to help reduce temperature variation on an internal side of the valve body compared to using a heater with uniform watt density across the heater.

[0081] In FIG. 5, the heater 500 is divided into six zones along a length of the heater 500. Here, the zones are designed with numerical labels (e.g., 0, 1, 2, etc.) and are used in the thermal simulations 600, 700. Specifically, a uniform watt density was used for zones 1 through 5 in the thermal simulation 600. In contrast, the watt densities were varied for zones 1 through 5 in the thermal simulation 700. As a specific example, the watt densities for zones 1 and 3 were lower than those of zones 2, 4, and 5 in the thermal simulation 700. Further, zone 0 was unheated for electrical lead connection(s). In other examples, the zones of the heater 500 can have a different distribution of watt densities. FIG. 5 is illustrative. In other examples, a heater for a heated valve can have another suitable configuration.

[0082] In FIG. 6, the thermal simulation 600 illustrates temperature variation across an internal side 602 of a valve body 604 resulting from uniform watt density for the heater 500. Here, the temperature is indicated using a graduated scale of dots against a contrast background. The resulting temperature variation on the internal side 602 of the valve body 604 was 31.6 degrees Celsius. Likewise, in FIG. 7, the thermal simulation 700 illustrates temperature variation across an internal side 702 of a valve body 704. In the example of FIG. 7, the temperature variation resulting from nonuniform watt densities across the heater 500, on the internal side 702 of the valve body 704, was 10.2 degrees Celsius. This relatively more uniform temperature profile seen in the thermal simulation 700 allows an excessively high operating temperature to be avoided for the heater 500. Thus, the heater 500 can be configured to output different watt densities as a function of location on the heater 500 in such a manner to conform to the nonuniform thermal mass of a valve body. FIGS. 6 and 7 are illustrative. In other examples, another suitable thermal simulation can be used to help optimize watt density as a function of location on a heater.

[0083] FIG. 8 schematically depicts an example heated valve 800 with a plurality of thermocouples attached at various locations each designated by an alphanumeric label (e.g., il, i2, etc.). FIG. 9 illustrates measured temperature as a function of time for locations i3, i4, i5 and i6 on the heated valve 800. Here, the measured temperatures are illustrated through a ramp-up stage and a gas flow introduction stage 900. Further, the setpoint (SP) was changed at 902. Likewise, FIG.Docket No. LRC25304PPCT10 illustrates measured temperature as a function of time for locations il, i2, i7 and i8 on the heated valve 800.

[0084] In FIG. 8, the heated valve 800 includes a valve body 802 and a valve flapper 804 contained within the valve body 802. Further, the heated valve 800 comprises a first heater assembly 806 held to the valve body 802. Similar to the first heater assembly 310, the first heater assembly 806 comprises a heater, a thermally conductive elastomer, a clamping structure, and a thermal insulator. The heater is configured to output different watt densities as a function of location on the heater to thereby heat at least a portion of an internal side of the valve body 802. Likewise, a second heater assembly 808 is held to the valve body 802. As depicted, the thermocouples i3, i4, i5, i6 were located on the internal side of the valve body 802. Further, the thermocouples il and i2 were located to alternative halves of the valve flapper 804. Additionally, the thermocouples i7 and i8 were located on a shaft connected to the heated valve 800 (the shaft is not depicted in FIG. 8). In some examples, the shaft can form a portion of a gas line on a semiconductor processing tool.

[0085] As can be seen in FIG. 9, the temperatures of the thermocouples i3, i4, i5, i6 on the internal side of the heated valve 800 varied by less than 20 degrees Celsius after the ramp-up stage and the gas flow introduction stage 900. This is significantly less than the temperature variation of over 35 degrees Celsius seen in FIG. 2B for a valve with cartridge heaters. In FIG. 10, the temperatures of the thermocouples il, i2, and i7, i8 on the valve flapper 804 and the shaft of FIG. 8 varied by less than 10 degrees Celsius after the ramp-up stage and the gas flow introduction stage 900. Thus, a heated valve as disclosed herein helps to reduce temperature nonuniformities on a heated valve compared to valves that utilize cartridge heaters.

[0086] In the above examples, a heater assembly utilizes a heater that is arranged in contact with an external side of a valve body. In other examples, a thermal interface material can be arranged between the heater and the external side of the valve body. FIG. 11 schematically depicts an exploded view of such an example heater assembly 1100 in relation to a portion of a heated valve 1102. The heated valve 1102 can be used on suitable semiconductor processing tools, such as the semiconductor processing tool 100 of FIG. 1, for example.

[0087] Similar to the first heater assembly 310, the heater assembly 1100 comprises a heater 1104 for heating at least a portion of an internal side 1106 of a valve body 1108 of the heated valve 1102. Additionally, a clamping structure 1110 in theDocket No. LRC25304PPCTform of a strap 1110A and screws 1110B is configured to hold the heater assembly 1100 to the valve body 1108. Further, a thermally conductive elastomer 1112 is arranged between the heater 1104 and the clamping structure 1110 in the heater assembly 1100. Additionally, a thermal insulator 1114 is arranged externally to the clamping structure 1110.

[0088] In the example of FIG. 11, the heater assembly 1100 further comprises a thermal interface material 1116 arranged between the heater 1104 and an external side 1118 of the valve body 1108. The thermal interface material 1116 can comprise suitable material(s) with a relatively high thermal conductivity, such as a graphite sheet, for example. Further, the thermal interface material 1116 helps to avoid air gaps between the heater 1104 and the external side 1118 compared to a heater assembly without a thermal interface material.

[0089] In some examples, the clamping structure 1110 can comprise a preform strap that is configured to follow a contour of the external side 1118. Alternatively, the clamping structure 1110 can comprise a flat strap that is bent in the shape of the external side 1118 during assembly of the heated valve 1102. This can help to reduce steps in a manufacturing process of the heated valve 1102.

[0090] While depicted in FIG. 11 with one heater assembly, it will be understood that the heated valve 1102 can include more than one heater assembly in various examples. In other examples, the heater assembly 1100 can comprise other suitable components. FIG. 11 is illustrative. In further examples, a heated valve may have another suitable configuration.

[0091] It will be understood that the configurations and / or approaches described herein are exemplary in nature, and that these specific examples or examples are not to be considered in a limiting sense, because numerous variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. As such, various acts illustrated and / or described may be performed in the sequence illustrated and / or described, in other sequences, in parallel, or omitted. Likewise, the order of the above-described processes may be changed.

[0092] The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems and configurations, and other features, functions, acts, and / or properties disclosed herein, as well as any and all equivalents thereof.

Claims

Docket No. LRC25304PPCTCLAIMS:

1. A heated valve for a semiconductor processing tool, the heated valve comprising:a valve body comprising an internal side; anda heater assembly configured to heat at least a portion of the internal side of the valve body, the heater assembly comprising a heater including an electrical insulator and a resistive trace embedded within the electrical insulator, wherein the heater is configured to output different watt densities as a function of a location on the heater.

2. The heated valve of claim 1, wherein the heater assembly further comprises a clamping structure to hold the heater assembly to the valve body.

3. The heated valve of claim 2, wherein the heater assembly further comprises a thermally conductive elastomer located between and in contact with the heater and the clamping structure.

4. The heated valve of claim 2 wherein the heater assembly further comprises a thermal insulator arranged externally to the clamping structure.

5. The heated valve of claim 1, wherein the heater assembly further comprises a thermal interface material arranged between the heater and an external side of the valve body.

6. The heated valve of claim 1, wherein the valve body comprises a channel on an external side, and the heater is arranged within the channel.

7. The heated valve of claim 1, wherein the electrical insulator comprises a polyimide, and the resistive trace comprises a nickel-containing metal trace.

8. The heated valve of claim 1, wherein the heater assembly is a first heater assembly configured to heat at least a first portion of the internal side of the valve body, and the heated valve further comprises a second heater assembly configured to heat at least a second portion of the internal side of the valve body.Docket No. LRC25304PPCT9. A semiconductor processing tool, comprising:a gas line; anda heated valve arranged along the gas line, the heated valve comprisinga valve body comprising an internal side, anda heater assembly configured to heat at least a portion of the internal side of the valve body, the heater assembly comprising a heater including an electrical insulator and a resistive trace embedded within the electrical insulator, wherein the heater is configured to output different watt densities as a function of a location on the heater.

10. The semiconductor processing tool of claim 9, wherein the gas line comprises an exhaust line.

11. The semiconductor processing tool of claim 9, wherein the heater assembly further comprises a clamping structure to hold the heater assembly to the valve body.

12. The semiconductor processing tool of claim 11, wherein the heater assembly further comprises a thermally conductive elastomer located between and in contact with the heater and the clamping structure.

13. The semiconductor processing tool of claim 11, wherein the heater assembly further comprises a thermal insulator arranged externally to the clamping structure.

14. The semiconductor processing tool of claim 11, wherein the valve body comprises a channel on an external side, and the clamping structure is configured to hold the heater within the channel.

15. The semiconductor processing tool of claim 9, wherein the heater assembly further comprises a thermal interface material located between the heater and an external side of the valve body.

16. The semiconductor processing tool of claim 9, wherein the electrical insulator comprises a polyimide, and the resistive trace comprises a nickel-containing metal trace.Docket No. LRC25304PPCT17. The semiconductor processing tool of claim 9, wherein the heater assembly is a first heater assembly configured to heat at least a first portion of the internal side of the valve body, and the heated valve further comprises a second heater assembly configured to heat at least a second portion of the internal side of the valve body.

18. A heater assembly for a heated valve, the heater assembly comprising:a heater including an electrical insulator and a resistive trace embedded within the electrical insulator;a clamping structure to hold the heater assembly to a valve body of the heated valve; anda thermally conductive elastomer located between the heater and the clamping structure.

19. The heater assembly of claim 18, wherein the heater is configured to output different watt densities as a function of a location on the heater.

20. The heater assembly of claim 18, wherein the electrical insulator comprises a polyimide, and the resistive trace comprises a nickel-containing metal trace.

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