Multi-zone heating enclosure for optimized sublimation of solid-phase precursors

Abstract

A heated enclosure for optimized sublimation of solid-phase semiconductor process material and subsequent delivery of the resulting vapor is provided. The enclosure has a hollow housing that is insulated to retain heat within the enclosure. The enclosure further has at least two independent heating zones with independent temperature control and dedicated overheat protection disposed within the housing, defining an upper heating zone and a lower heating zone. The lower heating zone is configured to receive a container that stores the solid-phase semiconductor process material. The enclosure further has a removable, height-adjustable divider made of insulating material, separating the upper heating zone from the lower heating zone and minimizing heat transfer between the upper heating zone and the lower heating zone.

Description

[Technical field]

[0001] This application claims the benefit of U.S. provisional patent application having Serial No. 63 / 227,842, filed on July 30, 2021.

[0002] The present disclosure relates generally to chemical delivery systems, and more particularly to chemical delivery systems using heated enclosures optimized for sublimation of solid-phase semiconductor process materials and subsequent delivery of the resulting vapors. [Background technology]

[0003] Chemical delivery systems, such as those commonly used in semiconductor manufacturing, often require heating process materials to meet the pressure and flow requirements of downstream equipment. In some cases, heating is necessary to support and maintain a phase change from liquid to vapor (evaporation) or from solid to vapor (sublimation). If the process material reverts to its previous stage, the process delivery lines will not maintain the required delivery conditions, resulting in process fluctuations, yield loss, or even interruptions to the process itself. This is especially important when working with process materials that undergo sublimation. The phase change from water vapor to solid can result in the deposited material clogging the process lines. Clogged lines can be very difficult and time consuming to clear.

[0004] To maintain the preferred gas phase, temperature and pressure conditions along the entire process material delivery line must be carefully monitored and controlled. In most chemical delivery systems, this often means elevating the temperature of the source vessel by using mechanisms such as resistive electric heaters or induction heaters. The process lines interconnecting the source vessel with downstream process tools are then heated using heat tracing attached directly to the piping and piping components in the process line.

[0005] Heat tracing, i.e., electrical resistance heating wire, is typically wrapped around each piping and piping component for the purpose of supplying heat. One or more layers of insulating tape are typically wrapped over the wire to prevent heat from dissipating to the surrounding environment. If the piping and piping components need to be repaired, the heat tracing must be unwound and removed. Heat tracing is effective and reliable if undisturbed, but when removed, the wire often breaks and must be replaced. Heat tracing and the insulating layers installed over the heat tracing require a lot of labor and time to install during initial production, remove for repair, and reinstall after the repair is made. There is a need to maximize the uptime of all tools used in semiconductor manufacturing, including the systems that supply the tools with gases and chemicals required for production, and therefore a need to increase the uptime of all systems that supply gases and chemicals to the tools. In addition, there is a need to reduce the footprint of the delivery systems caused by the increase in the number and size of piping, piping components, and chemical delivery cabinets in a given space.

[0006] Chemical vapor deposition (CVD) is a process in which a deposition surface (i.e., a substrate such as a silicon wafer) is contacted with vapors of volatile chemical compounds, typically at elevated temperatures. The compounds, or CVD precursors, are reduced or dissociated at the deposition surface, resulting in an adherent coating of a preselected composition within the deposition chamber. Precursors for use in CVD processes can be stored in a source vessel in gaseous, liquid, or solid form. The use of solid precursors is particularly challenging in terms of sublimation and subsequent transport of the precursor vapor to the substrate. Other more common concerns when designing CVD systems include the desire to minimize system downtime and the limited space available near the process tool where the precursor is applied. It would therefore be desirable to provide a chemical delivery system that addresses these challenges. Specifically, it would be desirable to provide a chemical delivery system that efficiently, effectively, and consistently delivers solid precursors in a CVD process while minimizing CVD system downtime and the amount of space occupied near the process tool.

[0007] As the use of solid-phase CVD precursors becomes more and more common, the number of processes requiring high temperatures (above 150° C.) is also increasing. At these temperatures, traditional heating methods for both source vessels and process lines may be infeasible due to lack of appropriate temperature ratings, insufficient heating power, or physical space constraints. Those skilled in the art have offered various solutions.

[0008] US Patent Publication No. 7,437,060 relates to a system for providing a controlled and stable vapor flow of vaporized liquid and solid source materials for use in CVD and ion implantation processes. The system is particularly useful for semiconductor manufacturing applications. US Patent Publication No. 2019 / 0177840 is directed to a chemical delivery system, particularly a chemical delivery system for delivering precursors during a CVD process. US Patent Publication No. 7,204,885 relates to CVD, particularly to a method for CVD including preheating of CVD precursors, a system for carrying out the method, and an apparatus produced by such a method. US Patent Publication No. 2019 / 0368039 teaches a Group VI transition metal-containing film-forming composition useful for depositing on a substrate via a deposition process. US Patent Publication No. 2019 / 0284684 discloses a sublimation gas supply system and a sublimation gas supply method for supplying sublimation gas of a solid material to a downstream process (e.g., a film formation process).

[0009] No. 6,953,047 teaches an apparatus for storing and delivering low vapor pressure process chemicals to a process tool for semiconductor manufacturing. The apparatus includes (a) a bulk container for storing the process chemicals, (b) a process container for delivering the process chemicals to the process tool, (c) a first manifold for delivering the process chemicals from the bulk container to the process container, (d) a solvent container for storing a quantity of solvent, and (e) a second manifold for delivering the process chemicals from the process container to the process tool. A process for using the apparatus is also contemplated.

[0010] One approach to address the needs and challenges identified above is to use a heating enclosure instead of a vessel heater and heat tracing. A heating enclosure has the advantage of covering the entire contents with a controlled temperature that can exceed the capabilities of conventional heating methods. In the present disclosure, several additional design elements are incorporated into the design of the source or process vessel oven that provides optimized performance for the delivery of sublimation vapor from solid phase precursors. Summary of the Invention

[0011] To meet these and other needs and challenges, and in view of its objects, the present disclosure provides a heated enclosure for optimized sublimation of solid-phase semiconductor process material and subsequent delivery of the resulting vapor. The enclosure has a hollow housing insulated to retain heat within the enclosure. The enclosure further has at least two independent heating zones with independent temperature control and dedicated overheat protection disposed within the housing, defining an upper heating zone and a lower heating zone. The lower heating zone is configured to receive a container that stores the solid-phase semiconductor process material. The enclosure further has a removable, height-adjustable divider made of insulating material, separating the upper heating zone from the lower heating zone and minimizing heat transfer between the upper heating zone and the lower heating zone.

[0012] The embodiments of the present invention can be used alone or in combination with each other. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the present disclosure.

[0013] The present disclosure is best understood from the following detailed description when read in connection with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to scale. Conversely, dimensions of the various features have been arbitrarily expanded or reduced for clarity. Included in the drawings are the following figures: [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a front perspective view of an oven in one embodiment of the present invention. [Diagram 2] FIG. 2 is a perspective top view of the oven shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The following detailed description provides only preferred exemplary embodiments and is not intended to limit the scope, applicability, or configuration of the present invention. Rather, the following detailed description of preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing preferred exemplary embodiments of the present invention. Various changes can be made in the function and arrangement of elements without departing from the spirit and scope of the present invention, as set forth in the appended claims.

[0016] For purposes of this specification and the appended claims, the term "predetermined" means predetermined, such that the predetermined characteristic must be determined, i.e., selected, or at least known, in advance of an event. For purposes of this specification and the appended claims, the term "piping" refers to one or more structures through which fluids may be transported between two or more parts of a system. For example, piping can include conduits, ducts, manifolds, and combinations thereof that transport liquids and / or gases at various pressures throughout a system.

[0017] For purposes of this specification and the appended claims, the term "fluid flow communication" refers to a property of connectivity between two or more components that allows liquids and / or gases to be transported between the parts in a controlled manner. Joining two or more parts so that they are in fluid flow communication with one another can include any suitable method known in the art, such as the use of flanged conduits, gaskets, and / or bolts.

[0018] As used herein, the terms "about," "approximately," and "substantially" are intended to correspond to ±5% of a stated numerical value or parameter (e.g., extending in a zero degree plane or flat). The terms "attached" and "affixed" mean that two components are joined, fastened, or connected to one another, either directly or indirectly (through an intervening part).

[0019] The terms "a" and "an" and "the" and similar reference words used in the context of describing the present invention (particularly in the context of the claims below) should be construed to include both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" are to be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise indicated. Recitation of ranges of numerical values ​​is merely intended to serve as a shorthand method of individually referring to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated herein as if it were individually recited herein. All methods described herein can be performed in any suitable order, unless otherwise indicated or clearly contradicted by context. The use of any and all examples or exemplary language (e.g., "such as") is intended merely to better describe the invention and does not limit the scope of the invention unless specifically claimed. No language in the specification should be construed as indicating any non-claimed element is essential to the practice of the invention. Use of the term "comprising" in this specification and claims includes the narrower terms "consisting essentially of" and "consisting of."

[0020] The embodiments are described, including the best mode known to the inventors for carrying out the invention. Variations of these embodiments will become apparent to those skilled in the art upon reading the following description. The inventors expect that skilled artisans will apply such variations as appropriate, and intend to carry out the invention in ways other than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the appended claims as permitted by applicable law. Moreover, this invention encompasses any combination of the described elements in all possible variations thereof unless otherwise indicated herein or clearly contradicted by context.

[0021] It is often necessary to distribute chemicals to a series of use points located within an industrial facility. For example, in a semiconductor manufacturing facility, liquid chemicals such as photoresist, slurry, hydrofluoric acid, hydrogen peroxide, ammonium hydroxide, etc. are distributed to various tools used in the production of semiconductors. Similarly, gas phase chemicals such as hydrogen fluoride, nitrogen trifluoride, and anhydrous ammonia may also require distribution in this manner. A source unit, which may typically be one or more pumps, chemical containers, or pressure vessels, directs the flow of fluids through a process delivery system having a series of valve manifolds used to connect the tools to the delivery system. In some cases, it is necessary or beneficial to heat pipes, valves, and vessels used within the system to improve the flow of fluids conducted within the system, especially when the fluids are viscous at lower temperatures and / or when room temperature is at or near the temperature at which the fluids change to (or from) the desired delivery material phase. The present disclosure addresses the need to provide such heat.

[0022] Referring now to the drawings, in which like reference numbers refer to like elements throughout the various views constituting the drawing, FIG. 1 shows an improved multi-zone heating enclosure or oven 1. Oven 1 provides for optimized sublimation of solid phase semiconductor process materials typically used in semiconductor manufacturing, and subsequent delivery of the resulting vapor of the solid phase semiconductor process material. A combination of features maximizes the performance of oven 1 in the areas of heating, cooling, and process material delivery capacity, safety, and maintainability.

[0023] Oven 1 has a top 8, a bottom 9, a pair of side walls, each defined by an outer side wall 16 and a corresponding inner side wall 17, and an inner rear wall 18, all of which combine to define a hollow enclosure. Oven 1 is generally rectangular in shape, as shown in FIG. 1, although other enclosure shapes are possible, including generally cubical, spherical, or ovoid, or irregular shapes. A reversible oven door (not shown) is attached to outer wall 16 and can be opened (to allow access to components inside the enclosure) or closed (to protect those components and retain heat within oven 1). Preferably, the door has a self-closing hinge and a triple-mounted compression latch.

[0024] One or more of the top 8, bottom 9, side walls, rear interior wall 18, and door are or include insulation to better retain heat within the oven 1. Preferably, these parts forming the body of the enclosure are all insulated. The insulation provided to the top 8, bottom 9, side walls, rear interior wall 18, and door may be, for example, about 2 inches (5 cm) thick, commercially available domestic oven insulation. The thickness of the insulation in the door may be thicker (e.g., about 2.75 inches or 7 cm) than the thickness of the insulation elsewhere in order to better retain heat within the oven 1. A more detailed description of suitable insulation is provided below.

[0025] Oven 1 has dual independent heating zones with independent temperature control and dedicated overheat protection. Thus, as shown in FIG. 1, oven 1 has an upper heating zone 10 and a lower heating zone 11. By "independent" we mean that the upper heating zone 10 can be controlled to have a temperature separate from the controlled temperature in the lower heating zone 11 (and vice versa). Temperature control is a process in which changes in temperature of a space (and collectively objects within that space) are measured or detected and the passage of thermal energy to or from the space is adjusted to achieve a desired temperature. A temperature controller receives inputs from temperature sensors and has outputs connected to control components such as heaters or fans. The temperature controller compares the actual temperature to a desired control temperature or set point and provides an output to the control component.

[0026] Over-temperature protection in the mains voltage is a protection system that cuts off the mains voltage if the internal temperature of the upper heating area 10 or the lower heating area 11 exceeds a predetermined value. A circuit is used to monitor and generate a trigger signal that initiates the shutdown process at undesirable high temperatures. High temperatures can occur due to various factors such as component failure, overload, overvoltage on the supply, failure of the cooling system, ventilation interruption, or other factors that overload the components.

[0027] The upper heating zone 10 and the lower heating zone 11 are separated or divided by a removable and adjustable divider 20. The divider 20 is a substantially flat, smooth and relatively thin piece made of a durable material capable of withstanding the high temperatures within both the upper heating zone 10 and the lower heating zone 11. The divider 20 is sized to fit snugly within the oven 1, contacting and extending between the side wall interior 17, the rear wall interior 18 and the door. Thus, for a rectangular shaped oven 1, the divider 20 is rectangular.

[0028] The divider plate 20 can be inserted into and removed from the oven 1 along the guide rails 21. Typically, a pair of guide rails 21 is provided, one for each of the side inner walls 17. However, another pair of guide rails 21 can also be provided for the rear inner wall 18. Different sets of guide rails 21 can be provided at different heights within the oven 1, so that the user has a choice when inserting the divider plate 20 and can adjust the height of the divider plate 20. Typically, the guide rails 21 are wall mounted. Alternatively, a single set of guide rails 21 can slide up and down within the oven 1 along a track and can be fixed at the desired height by a locking mechanism.

[0029] The ability to adjust the height of the divider 20 in the oven 1 achieves functional advantages. Such adjustability is useful, for example, to define the space in the upper heating zone 10 and the lower heating zone 11. It is also useful to account for differences in the height of cylinders placed in the oven 1. Thus, the divider 20 can be adjusted to allow full movement of the container (typically a cylindrical tank storing the precursor material) when the container is installed in or removed from the oven 1. Once adjusted in position in the oven 1, the divider 20 also functions to provide additional reinforcement to the container while it is in position in the oven 1.

[0030] Of course, it is possible to have multiple dividers 20 rather than just one. Multiple dividers 20 can divide the oven 1 into two or more heating zones. It would be within the knowledge of one skilled in the art to predetermine the number of dividers 20 required to best meet the needs of a particular application. The use of multiple (two or more) independent heating zones within the oven 1 serves to maximize the warm-up performance of the oven 1, prevent damage to valves installed in the process vessel, maintain temperature differentials during normal operation, and reduce the risk of process lines becoming clogged with redeposited process material.

[0031] Each of the upper heating zone 10 and the lower heating zone 11 is independently supplied with heat by using separate heaters. Thus, a heater 12 is provided to heat the upper heating zone 10, and a separate heater 14 is provided to heat the lower heating zone 11. The heaters 12 and 14 may be the same or different heating devices, depending on the application. In general, the heaters 12 and 14 may be any device that generates and radiates heat that functions to increase the temperature of the space (i.e., the upper heating zone 10 and the lower heating zone 11). Any one of several heating methods may be utilized, including a single heater with independent zones.

[0032] 1, heater 12 may comprise a single unitary component, and heater 14 may comprise two or more components (two components are shown). The number of components comprising heater 12 and heater 14 can be selected to accommodate the heating needs of upper heating zone 10 and lower heating zone 11 for different applications.

[0033] Regardless of its number of components, the heater 12 is mounted to the oven 1 in the upper heating zone 10. Any conventional mounting mechanism is suitable. An exemplary mounting mechanism is a mounting bracket 13 that is permanently attached to one or more of the side wall interior 17 and rear wall interior 18. Similarly, the heater 14 is mounted to the oven 1 in the lower heating zone 11 using one or more mounting brackets 15.

[0034] A portion of the heater 14 may be covered by a heat shield 27 constructed of a durable, thermally conductive material, such as stainless steel, capable of withstanding temperatures in excess of 200° C. The positioning of the heat shield 27 helps to delocalize the thermal impact of the heater 14 to the source or process vessel (not shown). By leaving a portion of the heater 14 uncovered by the heat shield 27, the temperature of the surface of the source or process vessel in front of the uncovered heater 14 can be selectively increased by 20° C. or more.

[0035] A source or process vessel (not shown) is positioned within oven 1, typically in lower heating zone 11, taking into account the weight of the vessel and the location of other components such as piping. If a vessel is damaged or empty and needs to be replaced or refilled, or if a vessel is desired to store a different material, the door is opened to access the vessel and the vessel is removed from oven 1. The same or a different vessel, as the case may be, can be reinserted or inserted into oven 1, after which the door is closed.

[0036] The container is held within oven 1 using any of a number of attachment mechanisms known to those skilled in the art. A suitable attachment mechanism is a combination of container mounting brackets 25 and tie-down chains 26. Tie-down chains 26 may be ropes, cables, or straps that can fasten or secure the container within oven 1 and prevent movement or other movement of the container during use. Optionally, a binder may be provided to tighten die-down chain 26 by taking up slack from the tie-down chain.

[0037] The container is placed on a weighing scale 30 located in a scale chamber 40 adjacent or near the bottom 9 of the oven 1. The scale 30 supports and measures the weight or mass of the container, thus allowing the amount of product remaining in the container to be measured. The scale 30 has an insulated scale platform 31 on which the container is placed directly. The scale platform 31 is preferably an integral part of the scale 30. (By "integral" we mean one monolithic part that is complete in itself without additional parts, i.e., one part formed as a unit with another part, a single part or a single integral part.) The scale platform 31 is insulated and sized to accommodate substantially the entire footprint of the oven 1, so that the scale platform 31 substantially insulates the scale chamber 40 from the heating areas 10, 11 located above the scale chamber 40. This provides thermal protection for the scale 30.

[0038] The scale chamber 40 forms an antechamber or sump at the bottom of the oven 1. The scale chamber 40 is ventilated to protect personnel and cool the scale 30. Ventilation can be accomplished by any suitable mechanism. As shown in FIG. 1, the scale chamber 40 has multiple ventilation inlets 41 (which may be louvers) located in front of the scale chamber 40 (below the door) and one or more ventilation ports 42 located in the sidewall of the oven 1. Not shown in FIG. 1 is a ventilation duct located in a portion of the rear interior wall 18 that partially forms the scale chamber 40. (A "portion" is any part that is separate from or integral with the whole.) In addition to cooling the scale 30, one or more of the ventilation inlets 41, ventilation ports 42, and ventilation ducts enable leak detection. (Leaks from components located within the oven 1, such as containers and connections to the containers, are deposited at the bottom of the oven 1, thereby serving to contain the leaks.)

[0039] Ventilation and air circulation are important in the heated zones 10, 11 as well as in the scale chamber 40. Proper ventilation and air circulation helps to remove and protect personnel from harmful gas phase process materials. Thus, the oven 1 includes components that facilitate ventilation and air circulation within the scale chamber 40 located at the bottom of the oven 1, within the heated zone 12 located at the top of the oven 1, and within the heated zone 11 located between the scale chamber 40 and the heated zone 12. The components that facilitate ventilation and air circulation within the scale chamber 40 are described above.

[0040] The scale platform 31 may have a number of lift rails 28 constructed of a durable material such as stainless steel attached to its upper surface via removable hardware such as welding or screws. The lift rails 28 serve to minimize the contact area between the process or source vessel (not shown) and the scale platform 31. This application has the positive effect of reducing heat loss from the process or source vessel to the scale platform 31. It also allows circulated air to contact the underside or process or source vessel. This increases the rate of heat transfer to the vessel during heating operations and increases the rate of heat transfer from the vessel during cooling operations.

[0041] Turning to components located in the heating area 11 that facilitate ventilation and air circulation, a circulation fan 50 is provided. The circulation fan 50 draws air in from an inlet and directs the air to one or more exhaust outlets 51. Thus, the circulation fan 50 circulates airflow around the oven 1 to maximize convective heat transfer. The circulation fan 50 may be ducted through the heater mounting bracket 15 and direct air downward toward the floor on which the oven 1 rests. Access to the circulation fan 50 from the interior of the oven 1 is facilitated by an access panel 52. Such access allows for maintenance of the circulation fan 50 and allows for the circulation fan 50 to be removed from the oven 1 through the front of the oven 1 when the door is open.

[0042] As highlighted in Figure 2, ventilation and fresh air is supplied to the upper heating zone 12 through the top 8 of the oven 1. A raised exhaust inlet 60 extends upwardly from the top 8 adjacent (adjacent as shown) to a fresh air inlet 61. The exhaust inlet 60 surrounds both an opening 64 that provides access to the interior of the oven 1 (i.e., upper heating zone 10), and a pressure relief flap valve 70. The pressure relief flap valve 70 provides overpressure protection by preventing a build-up of pressure within the oven 1 in the event of a leak while the heating is operating.

[0043] A single exhaust blast gate 62 is provided to selectively and simultaneously cover both the fresh air inlet 61 and the opening 64. Thus, the exhaust blast gate 62 covers the fresh air inlet 61 and the opening 64 when the exhaust blast gate 62 is closed (as shown in Figures 1 and 2) and leaves the fresh air inlet 61 and the opening 64 uncovered when the exhaust blast gate 62 is in its open position. A recessed portion 65 in the exhaust blast gate 62 allows access to the pressure relief flap valve 70 even when the exhaust blast gate 62 is closed.

[0044] An exhaust vent gate actuator 63 allows for selective opening and closing of the exhaust vent gate 62. Preferably, the exhaust vent gate actuator 63 is a pneumatic linear actuator with dual feed. Together, the components that provide ventilation and fresh air to the upper heating zone 12 through the top 8 of the oven 1 allow for control of the exhaust and fresh air within the oven 1. Such control allows for minimization of heat loss during heating and reduces the time required to cool the oven 1 to ambient temperature for access or maintenance.

[0045] The portion of the rear inner wall 18 partially forming the scale chamber 40, the portion of the rear inner wall 18 partially forming the lower heating zone 11, or the portion of the rear inner wall 18 partially forming the upper heating zone 12 may be formed wholly or partially as a false wall. In alternative embodiments, two or all three portions may have false walls. Of course, it is also possible to locate a false wall on one or both of the side walls.

[0046] False walls facilitate fresh air flow and ventilation. For example, by locating a circulating fan 50 near the false wall portion of the rear interior wall 18, the false wall fresh air inlet aids in cooling times. False walls are an effective way to shield an area from view. Because the primary purpose of a false wall is to obscure an area from view, false walls do not need to be load-bearing and are simpler to construct than regular bulkheads.

[0047] The access ports can be provided in various locations within the oven 1. For example, the access ports 75 can be located in the rear interior wall 18 and the upper heating area 10. Such access ports accommodate process piping, thermocouples, and other external structures, as well as increase circulation between different areas inside the oven. The access ports, and other components such as reversible oven doors, allow the oven 1 to be installed in multiple configurations within a larger delivery system. Among the access ports is the interconnect pass-through 80. As shown in FIG. 1, the interconnect pass-through 80 is formed by a first opening in one side wall and a second opening (preferably at the same height as the first opening) in a second side wall opposite the first side wall. Typically, the interconnect pass-through 80 is located approximately in the center of the width of each side wall for structural support.

[0048] It is often desirable to combine multiple ovens 1 in a supply system with multiple product containers and automated crossover capabilities. In one embodiment, such a system is configured with multiple ovens 1 connected by a common valve manifold heating enclosure (not shown). This configuration allows the individual container heating enclosures to be brought online and offline independently. Replacement of the depleted source container is completed at ambient temperature while the heating enclosures of the other containers are maintained at operating temperature, thus providing a continuous supply of process material. The common valve manifold heating enclosure remains at operating temperature throughout, as any drop in temperature could result in an undesirable phase change of the process material. It is common practice to keep downstream heating zones slightly warmer than the previous heating zone. This minimizes the possibility of undesirable phase changes in the process material.

[0049] Any remaining voids in the inter-chamber piping pass-through between the heating enclosures are filled with a compressible insulating material such as silicone rubber that not only directs heat to any interconnecting piping, but also acts as a thermal barrier when the upstream heating enclosure is at ambient temperature, for example during source vessel switchover.

[0050] As mentioned above, the one or more layers of insulation cover a majority of the surface area of ​​the components used in oven 1. The one or more layers of insulation may be attached with mechanical fasteners. In either method, the process of attaching the one or more layers of insulation may not include adhesives. As used herein, insulation means thermal insulation, and insulation may also include heat reflective materials, if desired.

[0051] The one or more layers of insulation may include (a) insulation boards and / or insulation attached to a plastic cover and / or insulation jacket made of flexible insulating material, and / or (b) custom manufactured to form-fit onto the part and / or molded to direct a volume of heated air toward the center of the part to which the insulation is attached. The one or more layers of insulation in any embodiment may be removably attached to the part using fasteners selected from bolts, screws, clamps, cable ties, magnets, adhesives, zippers, snaps, clasps, bungee cords, hooks and loops, Velcro® or other fastener strips, and the like.

[0052] Velcro® is the brand name of the first commercially available fabric hook-and-loop fastener, sold by Velcro USA, Inc. of Manchester, New Hampshire. The fastener was invented by George de Mestral. See U.S. Patent No. 3,009,235. A hook-and-loop fastener consists of two parts, typically two linear fabric strips or tapes (alternating round dots or squares) that are attached (e.g., sewn, glued, etc.) to the opposing surfaces to be fastened. The first part features small hooks (e.g., hook tape) and the second part features even smaller, "hairy" loops (e.g., loop tape). When the two surfaces are pressed together, the hooks catch on the loops, temporarily fastening or joining the two parts. When separated by pulling or peeling the two surfaces, the Velcro® strip produces a distinctive "popping" sound.

[0053] The insulation may include one or more pieces of insulation board or foam. The insulation may be a rigid sheet, such as a rigid foam or board, cut to cover at least a majority of the thermally conductive component. The insulation may also be cut or formed to allow passage of the component, as known to those skilled in the art. Alternatively, or additionally, the insulation board or foam may be formed or cut to form-fit at least a portion of the component. Additional layers of insulation may be added over one or more layers of insulation, with at least a portion of the bottom layer of insulation covering and / or contacting at least a portion of the thermally conductive component. The insulation cloth, board, or foam may be made from polystyrene foam, urethane foam, fiberglass, ceramic wool, cellulose, cork, silicone rubber, perlite, vermiculite, or others known in the art.

[0054] The present invention provides for faster manufacture and repair of oven 1 and systems that use oven 1. For example, a failed fan or other failed component can be easily accessed and repaired by removing some fasteners, typically mechanical fasteners such as nuts, bolts, screws, and / or others, and one or more layers of insulation, and then the oven 1 is ready to be reused after reinstalling one or more layers of insulation using one or more fasteners, if any, and any necessary purging steps.

[0055] Oven 1 also allows for maximization of uptime of all tools in a manufacturing facility that are supplied with the gases and chemicals required for manufacturing from a system that has oven 1 as part of it, and for increased uptime of a system that has oven 1. Oven 1 also minimizes the space required to supply the precursor materials, thereby allowing for an increased number of other components (pipes, valves, manifolds, supply vessels, etc.) in the same footprint. These and other advantages are provided by oven 1.

Claims

1. 1. A heated enclosure for optimized sublimation of solid phase semiconductor process materials and subsequent delivery of the resulting vapor, comprising: a hollow housing that is insulated to retain heat within the hollow housing and has a top and a bottom; at least two independent heating zones with independent temperature control and dedicated overheat protection disposed within the enclosure defining an upper heating zone and a lower heating zone, the lower heating zone being configured to receive a container storing the solid phase semiconductor process material; a removable, height-adjustable divider made of insulating material, separating the upper heating zone from the lower heating zone and minimizing heat transfer between the upper heating zone and the lower heating zone; a heat shield mounted between a heat source and the vessel; A heated enclosure.

2. The heating enclosure of claim 1 , further comprising a guide rail disposed within the housing, the divider plate being inserted into and removed from the housing along the guide rail.

3. 3. The heated enclosure of claim 1 or 2, further comprising the heat source including a first heater that supplies heat to the upper heating zone and a second heater that supplies heat to the lower heating zone.

4. The heated enclosure of claim 3 , wherein the first heater is secured to the housing in the upper heating region and the second heater is secured to the housing in the lower heating region.

5. The heating enclosure of claim 1 or 2, further comprising a mounting mechanism configured to retain the container within the housing.

6. 3. The heated enclosure of claim 1 or 2, further comprising a scale chamber positioned adjacent a bottom of the enclosure and a weighing scale positioned within the scale chamber, the weighing scale supporting and measuring the weight of the container, thus enabling a measurement of the amount of the process material remaining in the container.

7. 7. The heating enclosure of claim 6, wherein the oven has a footprint and the weighing scale has an insulated scale platform upon which the container rests directly, the scale platform sized to accommodate substantially the entire footprint of the oven so as to substantially insulate the scale chamber from the upper heating zone and the lower heating zone located above the scale chamber.

8. The heated enclosure of claim 6 , wherein the scale chamber is ventilated.

9. The heated enclosure of claim 6 , wherein a plurality of lift rails are attached to the scale platform.

10. 3. The heating enclosure of claim 1 or 2, further comprising a circulation fan disposed in the lower heating region to facilitate ventilation and air circulation.

11. 3. The heating enclosure of claim 1 or 2, further comprising an exhaust inlet and a fresh air inlet for providing a combined ventilation and fresh air supply to the upper heating zone.

12. 3. The heating enclosure of claim 1 or 2, further comprising a pressure relief flap valve providing overpressure protection.

13. 3. The heating enclosure of claim 1 or 2, further comprising at least one access port configured to accommodate process piping, thermocouples, and other external structure.

14. 3. The heated enclosure of claim 1 or 2, further comprising process piping disposed within an interconnect pass-through formed in an opening within the housing, the process piping fluidly communicating between the vessel when disposed within the housing and an external delivery system to deliver process material from the vessel to the external delivery system.

15. A chemical delivery system comprising the heated enclosure of claim 1.

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