High power lamp assembly for substrate processing

Abstract

Embodiments of the present disclosure include a thermal processing chamber comprising a radiant source assembly and a lamp assembly, which are adapted to perform one or more thermal processes that benefit from precise substrate process temperature control, improved substrate temperature uniformity, and rapid substrate temperature ramp rates during thermal processing. The embodiments of the disclosure provided herein include a radiant source assembly that includes a plurality of lamp assemblies that are positioned within a processing environment of a thermal processing chamber to heat a substrate positioned within the processing environment directly. The radiant source assembly and lamp assembly designs, as well as the materials used to form these assemblies, are configured to deliver high radiant energy fluxes and prevent significant outgassing during processing, thereby avoiding the common contamination issues associated with conventional lamps being positioned within the thermal processing chamber's processing environment.

Description

PATENTAttorney Docket No.: 44025742WO01HIGH POWER LAMP ASSEMBLY FOR SUBSTRATE PROCESSINGBACKGROUNDField

[0001] Embodiments of the present disclosure generally relate to lamps used in lamp-heated modules positioned within semiconductor substrate processing chambers.Description of the Related Art

[0002] Several processes for the thermal processing of substrates such as semiconductor wafers and other materials involve rapidly heating and cooling a substrate. Examples for such thermal processes include epitaxial (EPI) deposition processes and rapid thermal processing (RTP) processes, which are used in semiconductor device fabrication.

[0003] In either RTP or EPI processes, electromagnetic radiation from radiation sources is introduced into the process chamber and onto a semiconductor substrate in the processing chamber. In this manner, the substrate is rapidly heated to a processing temperature, which can be as high as 1800 °C. Not all of the radiant energy provided by the radiation sources actually heats the wafer. Some of the radiant energy is absorbed by the structural components of the chamber. In a conventional thermal processing chamber configuration, the radiation sources, such as lamp modules, are positioned outside of the thermal processing chamber and thus deliver the radiant energy through a semi-transparent chamber wall, which is typically formed of a quartz material. However, it has been found that in most conventional high-power rapid thermal processing applications, about 50% of the radiation emitted from most infrared (IR) lamps is absorbed by the semi-transparent chamber wall. The presence of the semi-transparent chamber wall between the substrate and lamps drastically increases the amount of power required to rapidly heat a substrate, due to the reduced radiation heat transfer to the substrate caused by the presence of the semi-transparent chamber wall positioned between the lamps and the substrate.PATENTAttorney Docket No.: 44025742WO01

[0004] In addition, it is desirable to maintain a uniform temperature across the surface of the substrate during thermal processing. A uniform temperature across the substrate enables uniform thermal processing of the substrate. Furthermore, temperature uniformity helps prevent thermal stress-induced substrate damage such as warping, defect generation, and crystallization slip. However, the presence of the semi-transparent chamber wall between the substrate and lamps also tends to reduce the ability to control the thermal uniformity of the heated substrate due to the semitransparent chamber wall averaging out the radiant energy provided locally to the surface of the substrate by each individual lamp.

[0005] To avoid the problems associated with including a semi-transparent chamber wall between the substrate and lamps during thermal processing, it has been proposed to position the lamps within the processing region of the thermal processing chamber. However, positioning the lamps inside a processing region of a thermal processing chamber creates a number of issues that have been known to affect the lifetime of the lamp, the cleanliness of the processes performed in the process chamber, and the ability to deliver the required large amount of electrical power to the lamps during thermal processing. Moreover, these problems are greatly increased in configurations that require rapid thermal processing at temperatures greater than 1000 °C in low-pressure (e.g., vacuum) environments due to contamination provided from the outgassing of the lamp components, and common lamp failure modes due to the high temperatures achieved by the lamps and the inability to cool the lamps during processing. In one example, some of the rapid thermal processes, such as EPI deposition processes, high-power IR lamps (>800 Watts / lamp) are required to achieve the desired processing temperatures at the desired temperature ramp rate. Also, maintaining the mechanical integrity of radiant heat portions of the IR lamps and their connections to external power sources is difficult when used in high-power configurations.

[0006] Therefore, there is a need for an improved IR lamp and lamp assembly design that solves the problems described above.PATENTAttorney Docket No.: 44025742WO01SUMMARY

[0007] Embodiments of the disclosure include a lamp assembly comprising: a lamp comprising a first pin, a second pin, and a coil, wherein a first end of the coil is coupled to the first pin and a second end of the coil is coupled to the second pin; a lamp base having a first end and a second end; a lamp interface material positioned between an exterior surface of the lamp and a surface of the lamp base formed at the first end of the lamp base, wherein the lamp interface material is configured to transfer heat generated by the lamp to the lamp base; a lamp connector coupled to the lamp base at the second end of the lamp base; a first conductive wire and a second conductive wire, wherein a first end of the first conductive wire is coupled to the first pin and a first end of the second conductive wire is coupled to the second pin; and a first sleeve and a second sleeve, wherein a first portion of the first sleeve is positioned between the lamp base and a first portion of the first pin and a first portion of the first conductive wire, and a first portion of the second sleeve is positioned between the lamp base and a first portion of the second pin and a first portion of the second conductive wire. In some embodiments, the lamp comprises a non-potting material containing lamp.

[0008] Embodiments of the disclosure may also include a radiant heat source assembly, comprising: a lamp assembly body comprising a plurality of openings formed therein, and a plurality of lamp assemblies, wherein the openings in the lamp assembly body each include a lamp assembly. The lamp assemblies each comprise: a lamp comprising a first pin, a second pin, and a coil, wherein a first end of the coil is coupled to the first pin and a second end of the coil is coupled to the second pin; a lamp base having a first end and a second end; a lamp interface material positioned between an exterior surface of the lamp and a surface of the lamp base formed at the first end of the lamp base, wherein the lamp interface material is configured to transfer heat generated by the lamp to the lamp base; a lamp connector coupled to the lamp base at the second end of the lamp base; a first conductive wire and a second conductive wire, wherein a first end of the first conductive wire is coupled to the first pin and a first end of the second conductive wire is coupled to the second pin; and a first sleeve and a second sleeve, wherein a first portion of the first sleeve is positionedPATENTAttorney Docket No.: 44025742WO01 between the lamp base and a first portion of the first pin and a first portion of the first conductive wire, a first portion of the second sleeve is positioned between the lamp base and a first portion of the second pin and a first portion of the second conductive wire, and the first sleeve and the second sleeve are positioned over a lower surface of a cavity formed in the lamp base. The radiant heat source assembly also includes a power distribution board comprising a plurality of connector pairs, wherein each connector pair comprises a first terminal and a second terminal, wherein a second end of the first conductive wire is coupled to the first terminal, and a second end of the second conductive wire is coupled to the second terminal.

[0009] Embodiments of the disclosure may also include a thermal processing system, comprising a thermal processing chamber, a radiant heat source assembly disposed within the interior region of the thermal processing chamber, and a power distribution board. The thermal processing chamber comprises: one or more walls configured to enclose an interior region; a substrate support disposed within the interior region; and an atmospheric control system, wherein the atmospheric control system comprises a vacuum pump that is configured to control a pressure of the interior region to a pressure less than atmospheric pressure. The radiant heat source assembly comprises: a lamp assembly body comprising a plurality of openings formed therein; a plurality of lamp assemblies configured to deliver electromagnetic radiation to the substrate support, wherein the openings in the lamp assembly body each include a lamp assembly. The lamp assemblies each comprise: a lamp comprising a first pin, a second pin, and a coil, wherein a first end of the coil is coupled to the first pin and a second end of the coil is coupled to the second pin; a lamp base having a first end and a second end; a lamp interface material positioned between an exterior surface of the lamp and a surface of the lamp base formed at the first end of the lamp base, wherein the lamp interface material is configured to transfer heat generated by the lamp to the lamp base; a lamp connector coupled to the lamp base at the second end of the lamp base; a first conductive wire and a second conductive wire, wherein a first end of the first conductive wire is coupled to the first pin and a first end of the second conductive wire is coupled to the second pin; and a first sleeve and a secondPATENTAttorney Docket No.: 44025742WO01 sleeve, wherein a first portion of the first sleeve is positioned between the lamp base and a first portion of the first pin and a first portion of the first conductive wire, a first portion of the second sleeve is positioned between the lamp base and a first portion of the second pin and a first portion of the second conductive wire, and the first sleeve and the second sleeve are positioned over a lower surface of a cavity formed in the lamp base. The power distribution board comprises a plurality of connector pairs, wherein each connector pair comprises a first terminal and a second terminal, wherein a second end of the first conductive wire is coupled to the first terminal, and a second end of the second conductive wire is coupled to the second terminal.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, 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 exemplary embodiments and are therefore not to be considered limiting of its scope, may admit to other equally effective embodiments.

[0011] Figure 1 is a simplified isometric view of an embodiment of a thermal processing chamber in accordance with one embodiment.

[0012] Figure 2 is a plan view of a radiant heat source in accordance with one or more embodiments.

[0013] Figure 3 is a side cross-sectional view of a portion of the radiant heat source in accordance with one or more embodiments.

[0014] Figure 4 is a side cross-sectional view of a portion of a lamp assembly of the radiant heat source in accordance with one or more embodiments.

[0015] Figure 5 is a side cross-sectional view of a portion of the radiant heat source that is partially disassembled in accordance with one or more embodiments.

[0016] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It isPATENTAttorney Docket No.: 44025742WO01 contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.DETAILED DESCRIPTION

[0017] Embodiments of the present disclosure include a thermal processing chamber comprising a radiant source assembly and a lamp assembly, which are adapted to perform one or more thermal processes that benefit from precise substrate process temperature control, improved substrate temperature uniformity, and rapid substrate temperature ramp rates during thermal processing. The embodiments of the disclosure provided herein include a radiant source assembly that includes a plurality of lamp assemblies that are positioned within a processing environment of a thermal processing chamber to heat a substrate positioned within the processing environment directly. The various thermal processing chamber configurations disclosed herein thus avoid the common issues created by the presence of semitransparent process chamber walls disposed between a radiant heat source and a substrate, which is commonly found in conventional thermal process chamber designs. The various processing chamber and lamp assembly configurations disclosed herein are adapted to avoid the inability of conventional thermal processing chambers to precisely control the temperature and temperature uniformity of a substrate during rapid thermal processing and improve the efficiency of the delivery of electromagnetic radiation to the substrate during thermal processing. The radiant source assembly and lamp assembly designs, as well as the materials used to form these assemblies, are configured to prevent significant outgassing during processing, thereby avoiding the common contamination issues associated with conventional lamps being positioned within the thermal processing chamber's processing environment.

[0018] Figure 1 is a simplified isometric view of one implementation of a thermal processing chamber 100 according to one implementation described herein. The thermal processing chamber 100 illustrated in Figure 1 includes a substrate support 104, a radiation source assembly 140, a radiation sensor 170, a stator assembly 118,PATENTAttorney Docket No.: 44025742WO01 a process kit 156, a controller 124, and a showerhead assembly 150. Figure 2 is a plan view of the top surface 114 of a radiant heat source 106 of the radiation source assembly 140 in accordance with one or more embodiments of the disclosure. Figure 3 is a side cross-sectional view of a portion of the radiant heat source 106 in accordance with one or more embodiments of the disclosure.

[0019] The thermal processing chamber 100 comprises a substrate support 104 and a chamber body 102 with sidewalls 108, a bottom wall 110, and a top wall 112, which define an interior volume 120. A processing region 115 is defined between the sidewalls 108, the substrate support 104, and the top wall 112. The sidewalls 108 typically include at least one substrate access port (not shown) to facilitate entry and egress of a substrate 141 (a portion of which is shown in Figure 1 ). The access port may be coupled to a transfer chamber (not shown) or a load lock chamber (not shown) and may be selectively sealed with a valve, such as a slit valve (not shown).

[0020] In one implementation, the substrate support 104 is annular, and the chamber 100 includes a radiant heat source 106 of the radiation source assembly 140, which is disposed below the substrate support 104 and within the interior volume 120. The substrate support 104 comprises an annular sidewall 152 with a substrate support ring 154 disposed thereon, which supports the substrate 141 . The radiant heat source 106 will include a plurality of lamp assemblies 420 (Figure 4) that each include a lamp 411.

[0021] In one implementation, the thermal processing chamber 100 includes a showerhead assembly 150 that includes gas distribution outlets to distribute gas evenly over a substrate to allow rapid and controlled heating and cooling of the substrate. The showerhead assembly 150 may be absorptive, reflective, or have a combination of absorptive and reflective regions. A gas source 183 is configured to provide one or more process gases, purge gases, or other useful gas(es) to the processing region 115 via the gas distribution outlets formed in the showerhead assembly 150.PATENTAttorney Docket No.: 44025742WO01

[0022] The thermal processing chamber 100 may also include a cooling block 180 adjacent to, coupled to, or formed in the top wall 112. Generally, the cooling block 180 is spaced apart and opposing the radiant heat source 106. The cooling block 180 comprises one or more coolant channels 184 coupled to an inlet 181 A and an outlet 181 B. The cooling block 180 may be made of a process resistant material, such as stainless steel, aluminum, a polymer, or a ceramic material. The coolant channels 184 may comprise a spiral pattern, a rectangular pattern, a circular pattern, or combinations thereof, and the channels 184 may be formed integrally within the cooling block 180. The inlet 181 A and outlet 181 B may be coupled to a coolant source 182 by valves and suitable plumbing and the coolant source 182 is in communication with the controller 124 to facilitate control of pressure and / or flow of a coolant fluid disposed therein. The fluid may be water, ethylene glycol, nitrogen (N2), helium (He), or other fluid used as a heat-exchange medium.

[0023] In the implementation shown, the substrate support 104 is optionally adapted to magnetically levitate and rotate within the interior volume 120. The substrate support 104 shown is capable of rotating while being raised and lowered vertically during processing, and may also be raised or lowered without rotation before, during, or after processing. In one implementation of the substrate support 104, an optional stator assembly 118 includes a drive assembly 168 that circumscribes the sidewalls 108 of the chamber body 102. The drive assembly 168 can include a coil 167 and current source 169 that is configured to be magnetically coupled to a magnet or magnetic material disposed within and / or coupled to the annular side wall 152 of the substrate support 104 during processing to provide rotational motion to the annular side wall 152, substrate support ring 154 and substrate 141 during processing. The drive assembly 168 is coupled to an actuator assembly 122 that is used in combination with the controller 124 to control the elevation of the drive assembly 168 along the exterior of the chamber body 102. The substrate support 104 is configured to function as a rotor, that is used to lift and / or rotate the substrate support 104 during processing. The stator assembly 118 may also include a housing 190 to enclose various parts and components of the stator assembly 118. In one implementation, each of the actuatorPATENTAttorney Docket No.: 44025742WO01 assemblies 122 generally comprise a precision lead screw 132 coupled between two flanges 134 extending from the sidewalls 108 of the chamber body 102. The lead screw 132 has a nut 158 that axially travels along the lead screw 132 as the screw rotates. A coupling 136 is coupled between the stator 118 and the nut 158 so that as the lead screw 132 is rotated, the coupling 136 is moved along the lead screw 132 to control the elevation of the stator 118 at the interface with the coupling 136. Thus, as the lead screw 132 of one of the actuators 122 is rotated to produce relative displacement between the nuts 158 of the other actuators 122, the horizontal plane of the stator 118 changes relative to a central axis of the chamber body 102. In one implementation, a motor 138, such as a stepper or servo motor, is coupled to the lead screw 132 to provide controllable rotation in response to a signal by the controller 124. Alternatively, other types of actuators 122 may be utilized to control the linear position of the stator 118, such as pneumatic cylinders, hydraulic cylinders, ball screws, solenoids, linear actuators and cam followers, among others.

[0024] The process kit 156 includes a plurality of lift pins (not shown) that are positioned between the substrate 141 and the radiant heat source 106, and are adapted to selectively contact and support the substrate 141 , to facilitate transfer of the substrate into and out of the thermal processing chamber 100. Each of the plurality of lift pins are configured to minimize absorption of energy from the radiant heat source 106. The plurality of lift pins (not shown) may be positioned and radially spaced apart from each other to facilitate the passage of an end effector coupled to a transfer robot (not shown).

[0025] The thermal processing chamber 100 includes a controller 124, which generally includes a central processing unit (CPU) 130, support circuits 128 and memory 126 that are adapted to control the components within the thermal processing chamber 100 during processing. The controller 124 is configured to perform one or more of the methods described herein using one or more algorithms stored in nonvolatile memory 126 and executed by the CPU 130. The CPU 130 may be any type of computer processor that can be used in an industrial setting to control various actions performed within the thermal processing chamber 100. The memory 126, orPATENTAttorney Docket No.: 44025742WO01 computer-readable medium, may be one or more of readily available memory such as random access memory (RAM), read-only memory (ROM), floppy disk, hard disk, or any other form of digital storage, local or remote, and is typically coupled to the CPU 130. The support circuits 128 are coupled to the CPU 130 for supporting the controller 124 in a conventional manner. These circuits include cache, power supplies, clock circuits, input / output circuitry, subsystems, and the like.

[0026] Referring to Figure 3, the radiant heat source 106 of the radiation source assembly 140 includes a plurality of lamp assemblies 420 that are configured to generate and provide electromagnetic radiation directly to a substrate 141 positioned within the interior volume 120 during processing. Figure 4 is a side cross-sectional view of a lamp assembly 420 that can be disposed within the radiant heat source 106 to heat a substrate disposed on the substrate support 104 according to one or more embodiments of the disclosure. The radiant heat source 106 includes a plurality of lamp assemblies 420 that are configured to provide electromagnetic radiation at desired wavelengths, such as wavelengths within the infra-red (IR) spectrum, to heat the substrate 141. In one implementation, as shown in Figures 2 and 3, the radiant heat source 106 includes a lamp assembly 302 that includes a plurality of tubes 160, which are formed within a lamp assembly body 303 (or simply body 303) in which the lamp assemblies 420 are positioned. Each tube 160, which comprises an opening formed within the lamp assembly body 303, contains a reflective material or reflective surface and a lamp assembly 420. In some embodiments, the body 303 includes a reflective coating that contains a material such as gold (Au), or silver (Ag). The body 303 may be made of a copper material or other suitable material to allow heat generated by the lamp assemblies to be transferred to a heat sink, such as portions of the chamber body 102. In some embodiments, a heat exchanging device 144 is configured to act as a heat sink to cool the body 303 by use of one or more fluid recirculating paths (not shown) formed within the body 303. In some embodiments, the body 303 optionally includes, or is coupled to, a separate heat exchanging block that includes one or more coolant channels (not shown) formed therein to provide a recirculating fluid a path to flow by use of a second coolant source (not shown).PATENTAttorney Docket No.: 44025742WO01

[0027] Referring to Figure 2, in some embodiments, the body 303 includes a plurality of tubes 160 that are formed in a close-packed hexagonal arrangement of tubes to provide a higher energy density of radiant heat from the radiant heat source 106. In one implementation, the radiant heat source 106 provides sufficient radiant energy to rapidly heat a substrate during a thermal process, such as an RTP process or an epitaxial deposition process. The radiant heat source 106 may further comprise annular zones, wherein the power supplied to the plurality of lamp assemblies 420 by controller 124 may be varied to enhance the radial or azimuthal distribution of energy from the lamp assemblies 420 to a surface of the substrate 141 .

[0028] An atmosphere control system 164 is also coupled to the interior volume 120 of the chamber body 102. The atmosphere control system 164 generally includes throttle valves and vacuum pumps for controlling chamber pressure within the interior volume 120 and processing region 115. The atmosphere control system 164 may additionally include gas sources for providing process or other gases to the interior volume 120 during processing. The atmosphere control system 164 may also be adapted to deliver process gases for thermal deposition processes, thermal etch processes, and in-situ cleaning of chamber components. The atmosphere control system 164 works in conjunction with the gas source 183 to control the pressure (e.g., atmospheric or negative pressures) and flow of gas(es) within the interior volume 120 of the thermal processing chamber 100.

[0029] The thermal processing chamber 100 also includes one or more radiation sensors 170, which may be adapted to sense radiation emitted from the substrate 141 before, during, and after processing. The one or more radiation sensors 170 may include a pyrometer or other optical measurement device that is configured to measure the temperature of a substrate. In the implementation depicted in Figure 1 , the radiation sensors 170 are disposed through the top wall 112, although other locations within and around the chamber body 102 may be used. The radiation sensors 170 may be adapted to be coupled to the top wall 112 to sense the temperature of a portion of the substrate.PATENTAttorney Docket No.: 44025742WO01

[0030] In some embodiments, the chamber 100 is adapted to receive a substrate in a "face-up" orientation, wherein the deposition receiving side or face of the substrate is oriented toward the showerhead assembly 150 and the "backside" of the substrate is facing the radiant heat source 106. The "face-up" orientation may allow the energy from the radiant heat source 106 to be absorbed more rapidly by the substrate 141 as the backside of the substrate may be less reflective than the face of the substrate.

[0031] During processing, the controller 124 receives data from the radiation sensors 170 and separately adjusts power delivered to each lamp of the radiant heat source 106, or individual groups of lamps or lamp zones, based on the received data. The controller 124 may include a power supply 143 that independently powers the various lamp assemblies 420 or lamp assemblies 420 disposed within two or more lamp zones, such as, for example, concentric and / or radial lamp assembly 420 containing zones.

[0032] In some embodiments, the lamp assemblies 420 of the radiant heat source 106 is coupled to a power distribution assembly 320 (Figure 3) that can include a power distribution board 321 that is positioned within the interior volume 120 and is configured to receive electrical power from the power supply 143 and distribute the received electrical power to each of the lamp assemblies 420 through connectors 323 formed on or within the power distribution board 321. In some embodiments, the power distribution board 321 includes a plurality of connector pairs, wherein each connector pair comprises a first connector (i.e. , first terminal) and a second connector (i.e., second terminal), wherein a second end of the first conductive wire is coupled to the first connector (i.e., first terminal), and a second end of the second conductive wire is coupled to the second connector (i.e., second terminal). In some embodiments, the power distribution board 321 includes electrical circuits 326 that include electrical traces 327 that are configured to distribute power from an input connection, which is coupled to the power supply 143, to each of the lamp assemblies 420 separately or to each lamp zone and then to each of the lamp assemblies 420 within the lamp zone. In some embodiments, the power distribution board 321 includes one or more electrical components (e.g., switches, ICs, relays, capacitors, inductors, resistors, etc.)PATENTAttorney Docket No.: 44025742WO01 that are coupled to the electrical circuits to control the delivery of power to the lamp assemblies 420 and / or the amount of power provided to the lamp assemblies 420. In some embodiments, the power distribution board 321 comprises a printed circuit board (e.g., FR-4, CEM-1 , or CEM-3 board materials) that includes an electrically insulating coating that is disposed over the exterior surface of the power distribution board 321 to trap and minimize the amount of outgassing of the materials disposed on or within the power distribution board 321 . An electrical insulating coating, such as a PEEK or other non-outgassing coating (e.g., polymeric or ceramic coating), is generally configured to reduce the amount of contamination provided to the components disposed within the interior volume 120 due to outgassing of the components within the power distribution board 321.

[0033] The controller 124 can be configured to provide a desired thermal processing substrate temperature profile, and based on comparing the data received from the sensors 170; the controller 124 adjusts power to the lamp assemblies 420 and / or lamp zones to conform the detected thermal data to the desired temperature profile. The controller 124 may also adjust the power provided to the lamp assemblies 420 and / or lamp zones as a function of time or during each thermal process to provide a consistent thermal treatment to each substrate processed in the processing chamber 100, in the event some chamber characteristics drift over time. Dynamic control of the heating of the substrate 141 may be affected by one or more radiation sensors 170 adapted to measure the temperature across the substrate 141 .

[0034] Referring to Figure 4, a lamp assembly 420 includes a radiant heat assembly 402 and a lamp mounting assembly 403. The radiant heat assembly 402 includes a lamp 411 that is positioned within an upper portion 414 of the lamp mounting assembly 403. In some cases, the lamp 411 is referred to herein as a “burner.” The lamp 411 includes a coil 412 that is electrically coupled to pins 415A and 415B, which are disposed at a lower region 413 of the lamp 411 . The coil 412 and pins 415A and 415B, which typically include one or more refractory metals (e.g., tungsten (W), tungsten alloy, molybdenum (Mo), or molybdenum alloy material), are configured to receive power that is delivered through the power distribution board 321 , andPATENTAttorney Docket No.: 44025742WO01 conducting elements found within the lamp mounting assembly 403, from the power supply 143. In some embodiments, to achieve a desired substrate heating ramp rate (e.g., > 600 °C / minute) and high processing temperatures greater than about 1800 °C, the winding density and length L1 of the coil 412 are sized to deliver a maximum radiant power density of about 38 to about 48 watts per millimeter of length L1 of the burner coil. In one example, the length L1 of the coil 412 are sized to deliver a radiant power density of about 27 to about 39 watts per millimeter of length L1 , to achieve a processing temperature that exceeds 1500 °C, such as a temperature of about 1600 °C. In some embodiments, to achieve the desired watts per millimeter of length L1 , the surface area of the filament is increased (i.e. filament overwind) or the number of turns on the winding mandrel used to make the coil 412 increased for a given coil 412 diameter.

[0035] In some embodiments, the lamp 411 comprises a non-potting material containing lamp structure, which essentially comprises the pins 415A, 415B that are coupled to the opposing ends of the coil 412 and a pinch-sealed optically transparent envelope structure (e.g., quartz or sapphire) that contains a halogen-containing gas in which the coil 412 is positioned. It has been found that lamps that contain potting materials are unreliable and will undesirably outgas (i.e., contaminate a substrate and adjacent components within the processing region of a chamber) when heated to even moderate processing temperatures and are positioned within a sub-atmospheric pressure environment. Further, it has been found that insufficient spacing (e.g. < 500 microns) between coil 412 and adjacent components reduces lamp life (i.e. lamp 411 explosion, at a processing temperature that exceeds 1500 °C). In one example, coil 412 concentricity with lamp 411 diameter D1 is 0.8 mm or lower.

[0036] In some embodiments, the radiant heat source 106 includes greater than 350 lamps 411 within a region that has a lateral diameter of between about 300 millimeters (mm) and about 450 mm, wherein the lamps 411 require a power of >800 Watts / lamp to achieve the desired ramp rate during processing. In one example, the radiant heat source 106 includes greater than 400 lamp assemblies within a region that has a diameter of about 350 millimeters (mm). In one example, the radiant heatPATENTAttorney Docket No.: 44025742WO01 source includes a power density of at least 3.4 Watts / mm2. In one example, the lamps 411 have a diameter D1 that is between 8 mm and 15 mm, such as between about 10 mm and about 14 mm in diameter, such as between about 11 mm and about 13 mm in diameter.

[0037] Referring to Figure 4, in some embodiments, the lamp mounting assembly 403 includes a lamp interface material 421 , a lamp base 416, conductive wires 426A, 426B, a lamp connector 417, and compliant elements 418. In some embodiments, the lamp base 416 is made of a ceramic or metal material that is configured to support and retain the other components found within the lamp mounting assembly 403. In some embodiments, the lamp base 416 is made of aluminum, nickel, copper, stainless steel, titanium, alumina, aluminum nitride, or other suitable thermally conductive materials that can be used as a structural element. In one example, the lamp base 416 comprises aluminum or nickel that is machined or formed into a shape that is adapted to support the other components found within the lamp mounting assembly 403.

[0038] The lamp assembly 420 will include a lamp interface material 421 that is configured to be positioned between an outer surface of the lamp 411 and an inner surface of the lamp base 416 to provide a thermally conductive path between the lamp 411 and the lamp base 416. The lamp interface material 421 is provided to allow the heat generated by the lamp 411 to be conducted away from the lamp 411 . The lamp interface material 421 , which is disposed around a lower exterior surface of the lamp 411 and above the pin 415A, 415B containing lower end of the lamp 411 , is also configured to form a seal between the lamp 411 and the lamp base 416 that is adapted to at least minimize the amount of light leakage into the lower portions of the lamp mounting assembly 403. The lamp interface material 421 will include a low outgassing flexible material that has a high-temperature stability, high thermal conductivity, and good chemical resistance. In some embodiments, the lamp interface material 421 exhibits an anisotropic heat transfer characteristic, allowing heat transfer in a preferred direction, such as the direction along the length of the lamp assembly 420 (e.g., the Z- direction). In one example, the lamp interface material 421 comprises a flexiblePATENTAttorney Docket No.: 44025742WO01 graphite material, such as Grafoil® that is available from Neograf Solutions, LLC or MinGraph® that is available from Mineral Seal Corporation. In some cases, the lamp interface material 421 includes a strip of material that can be wrapped around a region of the lamp 411. In another example, the lamp interface material 421 comprises rigid graphite. In some cases, the lamp interface material 421 includes separate pieces of flexible or rigid graphite material, allowing radiant heat assembly 402 and lamp mounting assembly 403 alignment and separable fixation.

[0039] In some embodiments, the lamp assembly 420 optionally includes a pair of conductive sleeves 424A, 424B, which are each configured to receive one of the pins 415A, 415B of a lamp 411. In some embodiments, the conductive sleeves 424A, 424B are configured to form a separable connection between each of the pins 415A, 415B and their respective conductive sleeves 424A, 424B to allow a lamp 411 to be removed from the lamp assembly 420 when a lamp 411 burns out or becomes damaged in some way. The right-most lamp assembly 420 shown in Figure 5 illustrates a configuration where the lamp 411 is separated from the lamp mounting assembly 403 of the lamp assembly 420. The conductive sleeves 424A, 424B will include a metal or metal alloy, such as nickel, nickel-coated copper, molybdenum, tungsten, or other useful metal that is coupled to conductive wires 426A, 426B, typically by use of a welding process. The conductive wires 426A, 426B can also include a solid or stranded metal or metal alloy, such as nickel, nickel-coated copper, molybdenum, tungsten, or other useful metal.

[0040] The lamp mounting assembly 403 may also include one or more pairs of insulating sleeves that are configured to electrically isolate the conductive wires 426A, 426B from portions of the lamp base 416, prevent arcing from occurring between the pins 415A, 415B, prevent arcing from occurring between the optional conductive sleeves 424A, 424B, and / or prevent arcing from occurring between the conductive wires 426A, 426B. In one or more embodiments, the lamp assembly 420 includes insulating sleeves 425 that are configured to separately electrically isolate portions of the pins 415A, 415B from each other and separately electrically isolate the pins 415A, 415B from the lamp base 416. The insulating sleeves 425 are also configured toPATENTAttorney Docket No.: 44025742WO01 separately electrically isolate a first portion of the conductive wires 426A, 426B from each other and separately electrically isolate the first portion of the conductive wires 426A, 426B from the lamp base 416. In some embodiments, the insulating sleeves 425 include an electrically insulating and low-outgassing material that may include a ceramic material such as alumina (AlxOy), aluminum nitride (AIN), zirconia (ZrOx), or other useful electrically insulating materials that have a desirable breakdown voltage at high operating temperatures.

[0041] In one or more embodiments, the lamp assembly 420 also includes insulating sleeves 428 that are configured to separately electrically isolate a second portion of the conductive wires 426A, 426B from each other and separately electrically isolate the second portion of the conductive wires 426A, 426B from the lamp base 416. In some configurations, a portion of each insulating sleeve 428 overlaps with a portion of the insulating sleeve 425. In one example, as shown in Figure 4, an outer diameter of the insulating sleeves 428 is smaller than the inner diameter of the insulating sleeves 425 so that a portion of the insulating sleeve 428 can be positioned within a portion of the insulating sleeve 425. In some embodiments, the insulating sleeves 428 includes an electrically insulating and low-outgassing material that may comprise a ceramic material such as alumina (AlxOy), aluminum nitride (AIN), zirconia (ZrOx), or other useful electrically insulating materials that have a desirable breakdown voltage at high operating temperatures and that either have a high or low thermal conductivity to increase or decrease, respectively, the thermal gradient from the hotter radiant heat assembly 402 to the cooler lamp mounting assembly 403.

[0042] In some embodiments, an inner diameter of the insulating sleeves 428 is configured to form a small gap or location-fit type non-existent gap between the inner diameter of the insulating sleeves 428 and the outer diameter of a conductive wire 426A, 426B to prevent stray electromagnetic radiation generated by the lamp 411 from being transmitted to the lower portion of the lamp assembly 420.

[0043] The lamp assembly 420 also includes a lamp connector 417 that is coupled to a lower portion of the lamp base 416 and is configured to support, separate, andPATENTAttorney Docket No.: 44025742WO01 electrically isolate the lower portions of the conductive wires 426A, 426B, which extend through the lamp connector 417 and past a lower surface 433 of the lamp connector 417. The lamp connector 417 is configured to guide the ends of the conductive wires 426A, 426B to be brought into direct contact with the connectors 323 of the power distribution board 321 . The lamp connector 417 can include shoulder regions 435 that are configured to support and vertically position the insulating sleeves 428 within the lower region of the lamp mounting assembly 403. The lamp connector 417 includes an insulating and low-outgassing material that can be fixedly coupled to (e.g., press fit into) a lower portion of the lamp base 416. In some embodiments, the lamp connector 417 comprises a non-conductive and semi-compliant material. In one example, the lamp connector 417 comprises a machined or injection molded thermoplastic material, such as PEEK, PTFE, PVDF, Vespel, PPS, PEI, or other suitable materials.

[0044] In some embodiments, the lamp assembly 420 also includes compliant elements 418 that are positioned to support and electrically isolate portions of each of the conductive wires 426A, 426B that extend past the lower surface of the lamp connector 417 and provide the ends of the conductive wires 426A, 426B with some support and additional flexibility to allow the ends of the conductive wires 426A, 426B to be received within the connectors 323 of the of the power distribution board 321 . In some embodiments, the compliant elements 418 include a low-outgassing material and non-conductive electrically insulating polymeric material, such as an elastomer, such as Viton, perfluoroelastomers (FFKM), fluorosilicone (FVMQ), or other useful material.

[0045] Referring back to Figure 4, in some embodiments, the lamp base 416 includes features that are configured to prevent stray electromagnetic radiation, which is generated by the lamp 411 , from being received by one or more of the components within a lower portion of the lamp mounting assembly 403 and the power distribution assembly 320 to prevent the undesirable heating and / or overheating of these elements during processing. In one example, the lamp base 416 includes a cavity 430 that is configured to receive at least a portion of the insulating sleeves 425. The cavity 430 includes a shoulder region 427 positioned at the lower end of the cavity 430, and isPATENTAttorney Docket No.: 44025742WO01 configured to support and vertically position the insulating sleeves 425 within an upper region of the lamp mounting assembly 403. In some configurations, as shown in Figure 4, the shoulder region 427 forms a base surface of a cavity that is configured to block and reflect any stray electromagnetic radiation from being transmitted to the lower region of the lamp mounting assembly 403. In some cases, the formed cavity 430 includes two partially separated cavities that are each configured to retain and support an insulating sleeve 425. Additionally, in some embodiments, the lamp base 416 includes wire supporting features 429 that are formed through the shoulder region 427 of the cavity 430 and are configured to support and guide the conductive wires 426A, 426B through the lower portion of the lamp mounting assembly 403. The wire supporting features 429 include openings that are sized to form a small gap or location fit type non-gap configuration with the outer diameter 436 of the insulating sleeves 428. The combination of the shoulder region 427, the wire supporting features 429, and the configuration of the insulating sleeves 425 and 428, as described above, is configured to block the stray electromagnetic radiation from reaching the components within the lower portion of the lamp mounting assembly 403.

[0046] In some embodiments, the lamp base 416 includes one or more ports 419 that are configured to vent gases that may be trapped within the lamp mounting assembly 403 when the lamp assembly 420 is positioned within a sub-atmospheric pressure environment. The one or more ports 419 can thus be used to prevent a virtual leak within the interior volume 120 during thermal processing. In one embodiment, the one or more ports 419 are formed within the lamp base 416 to vent gases trapped within the cavity region formed between the lower portion of the lamp interface material 421 and the shoulder region 427 within the lamp mounting assembly 403. In some embodiments, the ports 419 can be used to distribute high thermal conductivity gas (e.g. helium, hydrogen, etc.), from the atmosphere control system 164, to conductively couple the lamp assembly 420, radiation source assembly 140, and the heat exchanging device 144.

[0047] In some embodiments, the lamp assembly 420 includes one or more electrical fuses (not shown) that are connected in series with at least one of thePATENTAttorney Docket No.: 44025742WO01 conductive wires 426A, 426B. The one or more fuses can be positioned within a lower portion of the lamp mounting assembly 403. In one example, a fuse is positioned in a region of the lamp mounting assembly 403 that is adjacent to or within the lamp connector 417.

[0048] Referring to Figure 5, in some embodiments of the radiant heat source 106, the lamp assemblies 420 are each separable from the body 303 of the lamp assembly 302 and power distribution board 321 as shown by the left-most lamp assembly 420 shown in Figure 5. In some configurations, where the conductive sleeves 424A, 424B are not provided within the lamp assemblies 420 the ability to remove the complete lamp assembly will be required when a lamp 411 burns out. However, in some other embodiments, the lamp 411 is separable from the lamp assembly 420 as shown by the right-most lamp assembly 420 shown in Figure 5. In this configuration, the lamp 411 and lamp interface material 421 can be removed as a combined assembly so that new lamp 411 and lamp interface material 421 assembly can be positioned and form a seal with the remaining parts of the lamp assembly 420.

[0049] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

PATENTAttorney Docket No.: 44025742WO01What is claimed is:1 . A lamp assembly comprising: a lamp comprising a first pin, a second pin, and a coil, wherein a first end of the coil is coupled to the first pin and a second end of the coil is coupled to the second pin; a lamp base having a first end and a second end; a lamp interface material positioned between an exterior surface of the lamp and a surface of the lamp base formed at the first end of the lamp base, wherein the lamp interface material is configured to transfer heat generated by the lamp to the lamp base; a lamp connector coupled to the lamp base at the second end of the lamp base; a first conductive wire and a second conductive wire, wherein a first end of the first conductive wire is coupled to the first pin and a first end of the second conductive wire is coupled to the second pin; and a first sleeve and a second sleeve, wherein a first portion of the first sleeve is positioned between the lamp base and a first portion of the first pin and a first portion of the first conductive wire, and a first portion of the second sleeve is positioned between the lamp base and a first portion of the second pin and a first portion of the second conductive wire.

2. The lamp assembly of claim 1 , wherein the lamp comprises a non-potting material containing lamp.

3. The lamp assembly of claim 2, wherein the lamp comprises a halogen gas.

4. The lamp assembly of claim 1 , wherein lamp base comprises a metal selected from a group consisting of nickel, aluminum, copper, stainless steel, or titanium.PATENTAttorney Docket No.: 44025742WO015. The lamp assembly of claim 1 , wherein the lamp interface material is configured to form a seal between the exterior surface of the lamp and the surface of the lamp base.

6. The lamp assembly of claim 5, wherein the lamp interface material comprises a graphite-containing material.

7. The lamp assembly of claim 1 , wherein the first sleeve and the second sleeve are positioned over a lower surface of a cavity formed in the lamp base, and the lamp assembly further comprises a third sleeve and a fourth sleeve, and wherein a first portion of the third sleeve is positioned between the lamp base and a second portion of the first conductive wire, a first portion of the fourth sleeve is positioned between the lamp base and a second portion of the second conductive wire, and a second portion of the third sleeve and a second portion of the fourth sleeve are positioned within the cavity formed in the lamp base.

8. The lamp assembly of claim 1 , further comprising: a first conductive sleeve is disposed between the first conductive wire and the first pin, wherein the first pin is separable from the first conductive sleeve, and the first conductive sleeve is coupled to the first conductive wire; and a second conductive sleeve is disposed between the second conductive wire and the second pin, wherein the second pin is separable from the second conductive sleeve, and the second conductive sleeve is coupled to the second conductive wire.

9. The lamp assembly of claim 1 , wherein the lamp connector comprises a thermoplastic material.

10. The lamp assembly of claim 1 , further comprising: a first compliant element that is configured to support a portion of the first conductive wire, andPATENTAttorney Docket No.: 44025742WO01 a second compliant element that is configured to support a portion of the second conductive wire, wherein the first and second compliant elements comprise an elastomeric material.

11. A radiant heat source assembly, comprising: a lamp assembly body comprising a plurality of openings formed therein; a plurality of lamp assemblies, wherein the openings in the lamp assembly body each include a lamp assembly, and the lamp assemblies each comprise: a lamp comprising a first pin, a second pin, and a coil, wherein a first end of the coil is coupled to the first pin and a second end of the coil is coupled to the second pin; a lamp base having a first end and a second end; a lamp interface material positioned between an exterior surface of the lamp and a surface of the lamp base formed at the first end of the lamp base, wherein the lamp interface material is configured to transfer heat generated by the lamp to the lamp base; a lamp connector coupled to the lamp base at the second end of the lamp base; a first conductive wire and a second conductive wire, wherein a first end of the first conductive wire is coupled to the first pin and a first end of the second conductive wire is coupled to the second pin; and a first sleeve and a second sleeve, wherein a first portion of the first sleeve is positioned between the lamp base and a first portion of the first pin and a first portion of the first conductive wire, a first portion of the second sleeve is positioned between the lamp base and a first portion of the second pin and a first portion of the second conductive wire, and the first sleeve and the second sleeve are positioned over a lower surface of a cavity formed in the lamp base; and a power distribution board comprising a plurality of connector pairs, wherein each connector pair comprises a first terminal and a second terminal, wherein aPATENTAttorney Docket No.: 44025742WO01 second end of the first conductive wire is coupled to the first terminal, and a second end of the second conductive wire is coupled to the second terminal.

12. The lamp assembly of claim 11 , wherein the lamp comprises a non-potting material containing lamp, and a halogen gas.

13. The lamp assembly of claim 11 , wherein lamp base comprises a metal selected from a group consisting of nickel, aluminum, copper, stainless steel, or titanium.

14. The lamp assembly of claim 11 , wherein the lamp interface material is configured to form a seal between the exterior surface of the lamp and the surface of the lamp base.

15. The lamp assembly of claim 14, wherein the lamp interface material comprises a graphite-containing material.

16. The lamp assembly of claim 11 , further comprising: a third sleeve and a fourth sleeve, wherein a first portion of the third sleeve is positioned between the lamp base and a second portion of the first conductive wire, a first portion of the fourth sleeve is positioned between the lamp base and a second portion of the second conductive wire, and a second portion of the third sleeve and a second portion of the fourth sleeve are positioned within the cavity formed in the lamp base.

17. The lamp assembly of claim 11 , further comprising: a first conductive sleeve is disposed between the first conductive wire and the first pin, wherein the first pin is separable from the first conductive sleeve, and the first conductive sleeve is coupled to the first conductive wire; and a second conductive sleeve is disposed between the second conductive wire and the second pin, wherein the second pin is separable from the second conductive sleeve, and the second conductive sleeve is coupled to the second conductive wire.PATENTAttorney Docket No.: 44025742WO0118. The lamp assembly of claim 11 , wherein the lamp connector comprises a thermoplastic material.

19. The lamp assembly of claim 11 , further comprising: a first compliant element that is configured to support a portion of the first conductive wire, and a second compliant element that is configured to support a portion of the second conductive wire, wherein the first and second compliant elements comprise an elastomeric material.

20. A thermal processing system, comprising a thermal processing chamber, comprising: one or more walls configured to enclose an interior region; a substrate support disposed within the interior region; and an atmospheric control system, wherein the atmospheric control system comprises a vacuum pump that is configured to control a pressure of the interior region to a pressure less than atmospheric pressure; a radiant heat source assembly disposed within the interior region of the thermal processing chamber, comprising: a lamp assembly body comprising a plurality of openings formed therein; a plurality of lamp assemblies configured to deliver electromagnetic radiation to the substrate support, wherein the openings in the lamp assembly body each include a lamp assembly, and the lamp assemblies each comprise: a lamp comprising a first pin, a second pin, and a coil, wherein a first end of the coil is coupled to the first pin and a second end of the coil is coupled to the second pin; a lamp base having a first end and a second end; a lamp interface material positioned between an exterior surface of the lamp and a surface of the lamp base formed at the first end ofPATENTAttorney Docket No.: 44025742WO01 the lamp base, wherein the lamp interface material is configured to transfer heat generated by the lamp to the lamp base; a lamp connector coupled to the lamp base at the second end of the lamp base; a first conductive wire and a second conductive wire, wherein a first end of the first conductive wire is coupled to the first pin and a first end of the second conductive wire is coupled to the second pin; and a first sleeve and a second sleeve, wherein a first portion of the first sleeve is positioned between the lamp base and a first portion of the first pin and a first portion of the first conductive wire, a first portion of the second sleeve is positioned between the lamp base and a first portion of the second pin and a first portion of the second conductive wire, and the first sleeve and the second sleeve are positioned over a lower surface of a cavity formed in the lamp base; and a power distribution board comprising a plurality of connector pairs, wherein each connector pair comprises a first terminal and a second terminal, wherein a second end of the first conductive wire is coupled to the first terminal, and a second end of the second conductive wire is coupled to the second terminal.

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