Ampoule for a semiconductor precursor material

Abstract

This invention describes a bottom-fed ampoule for semiconductor manufacturing precursors and its method of use. The ampoule includes an outer cylindrical wall and an inner cylindrical wall defining a flow channel therebetween, and a bottom wall having a plurality of concentric elongated walls on its top surface. An opening in each wall is offset from an opening in an adjacent wall, thereby defining a gas exchange zone through which a carrier gas flows and contacts the precursor.

Description

Technical Field

[0001] This disclosure generally relates to ampoules for use in semiconductor manufacturing precursors and methods of using them. Specifically, this disclosure relates to ampoules and methods for providing a bottom-fed sublimation bed and a curved flow path for low vapor pressure precursors. Prior Technology

[0002] The semiconductor industry is using an increasing variety of liquid and solid chemical substances in chemical vapor deposition (CVD) and atomic layer deposition (ALD) processes. Precursors are typically contained in closed containers or ampoules with a single inlet and a single outlet.

[0003] Solid precursors with low vapor pressure often use a carrier gas to carry vapor from the ampoule to the process reactor. For these types of processes, two types of ampoules are typically used: bubblers, where the inlet carrier gas enters a conduit immersed in the precursor; and cross-flow ampoules, where the carrier gas sweeps across the top space of the ampoule from top to bottom. Typically, the carrier gas has only one very short flow path. This short path from the container's inlet to outlet does not allow sufficient residence time within the container, preventing the vaporized or sublimated precursor in the carrier gas from becoming fully saturated. Some existing ampoule designs fail to uniformly distribute the carrier gas across the entire surface of the precursor. Some existing ampoule designs fail to adequately heat the precursor throughout the container. Many other solid-state source ampoules do not provide a means to prevent precursor powder from migrating downstream, which can impede the effectiveness of control valves or cause particle problems on the wafer.

[0004] A conventional top-fed sublimation architecture comprises an ampoule or can partially filled with a solid precursor, which is placed at the bottom of the ampoule. When the ampoule is heated and a carrier gas is introduced into the top space of the ampoule, sublimation occurs between the top surface of the solid precursor and the carrier gas in the top space. Ideally, the carrier gas flowing through the ampoule becomes saturated with the precursor. As the top space of the ampoule increases, the concentration of the saturated carrier gas changes, resulting in inconsistent supply of precursor-carrier gas dosage. Consequently, due to inefficiency in the ampoule and depletion of the solid precursor, carrier gas saturation cannot be maintained.

[0005] This technical field requires ampoules that have one or more of the following characteristics: increased flow path, increased sublimation surface area, and consistent saturated carrier gas concentration; methods for manufacturing ampoules; and methods for using ampoules. Summary of the Invention

[0006] One or more embodiments relate to a bottom-fed ampoule for semiconductor precursor materials, having a curved path to increase residence time. The ampoule includes an outer cylindrical wall, an inner cylindrical wall, a bottom wall, an outlet conduit, and a cap.

[0007] The outer cylindrical wall has an inner surface and an outer surface. The inner cylindrical wall has an inner surface and an outer surface, and its outer diameter is smaller than that of the outer cylindrical wall, thus forming an inlet channel between the inner and outer cylindrical walls. The top surface of the bottom wall has a plurality of concentric elongated walls, each wall including an opening offset from the openings in adjacent walls. The outlet conduit has an inner surface and an outer surface, and its outer diameter is smaller than that of the inner cylindrical wall to form a cavity, and its inner diameter defines the outlet channel. The cover has a bottom surface that contacts one or more of the outer cylindrical wall, the inner cylindrical wall, or the outlet conduit to seal the inlet channel and the cavity, and the cover has an inlet opening in fluid communication with the inlet channel and an outlet opening in fluid communication with the outlet conduit.

[0008] In some embodiments, the ampoule further includes a filter medium in contact with the top surface of each of the concentric elongated walls. In some embodiments, a gas exchange zone is formed between the filter medium, the plurality of concentric elongated walls, and the bottom wall, the exchange zone forming a tortuous path for gas to flow from the inlet channel to the outlet conduit. In some embodiments, a solid precursor is placed above the filter medium such that depletion of the solid precursor does not result in a change in concentration in the gas exchange zone. In some embodiments, the filter medium is secured between the outer retaining ring and the bottom surface of the inner cylindrical wall, while in other embodiments, the filter medium is secured between the outer retaining ring and the bottom surface of the inner cylindrical wall.

[0009] In some embodiments, the outer retaining ring is secured to the bottom surface of the inner cylindrical wall by a plurality of fasteners. In some embodiments, the filter medium is fixed between the inner retaining ring and the bottom surface of the outlet conduit.

[0010] In some embodiments, the bottom end of the inner cylindrical wall includes an inner oblique flange. In some embodiments, the outer cylindrical wall and the bottom wall are integral. In some embodiments, the outer cylindrical wall is removably secured to the bottom wall by a plurality of fasteners.

[0011] In some embodiments, the outlet conduit and the bottom surface of the cap are integral. In some embodiments, the inner cylindrical wall and the bottom surface of the cap are integral.

[0012] In some embodiments, the ampoule further includes a top wall integral with the top surface of the inner cylindrical wall, the top surface of which contacts the bottom surface of the cap.

[0013] In some embodiments, the top surface of the outer cylindrical wall includes a groove with an O-ring.

[0014] In some embodiments, a flange extends outward from the top surface of the outer cylindrical wall and contacts the bottom surface of the cover.

[0015] Other embodiments include a bottom wall having a top surface having a plurality of concentric elongated walls, each wall having an opening offset from an opening in an adjacent wall, the bottom wall having a diameter larger than the inner diameter of an outer cylindrical wall, the outer cylindrical wall being removably secured to the bottom wall by a plurality of fasteners.

[0016] Some embodiments relate to a method for saturating a carrier gas, comprising the following steps: introducing a carrier into an ampoule via an inlet channel; pushing the carrier gas into a gas exchange zone formed between a plurality of concentric elongated walls protruding from the bottom wall and a filter medium disposed above the plurality of concentric walls; saturating the carrier gas in the gas exchange zone with vaporization precursors by passing the carrier gas through an inlet of the outermost elongated wall of the plurality of elongated walls to an outlet of the innermost elongated wall of the plurality of elongated walls; and discharging the carrier gas through an outlet conduit.

[0017] In some embodiments, the method further includes heating the solid precursor and passing the vaporized solid precursor through a filter medium.

[0018] In some embodiments, the exchange zone forms a curved path that allows the carrier gas to flow from the inlet channel to the outlet duct. Simple Explanation of the Diagram

[0019] To understand in detail the above-described features of the invention, the invention briefly outlined above can be described more specifically with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only typical embodiments of the invention and should therefore not be considered as limiting the scope of the invention, as other equivalent embodiments are permissible under this disclosure.

[0020] Figure 1 is a schematic diagram of an ampoule with a meandering configuration according to one embodiment of the present disclosure;

[0021] Figure 2 illustrates a cross-sectional view of an ampoule with a meandering configuration according to one embodiment of the present disclosure;

[0022] Figure 3 illustrates a detailed cross-sectional view showing a bottom wall that is removably secured to the outermost wall of the ampoule; and

[0023] Figure 4 is a bottom view of an ampoule with a meandering configuration according to one embodiment of the present disclosure.

[0024] In the accompanying drawings, similar parts and / or features may have the same element symbol. Additionally, parts of the same type can be distinguished by adding a dash and a second symbol after the element symbol to differentiate similar parts. If only the first element symbol is used in the specification, the description applies to any of the similar parts having the same first element symbol, regardless of the second element symbol. The shading of intersecting lines in the drawings aids in the visualization of different parts and does not necessarily indicate different structural materials. Implementation

[0025] Before describing several exemplary embodiments of the invention, it should be understood that the invention is not limited to the details of the construction or process steps set forth in the following description. The invention can have other embodiments and can be practiced or implemented in various ways.

[0026] Some embodiments of this disclosure advantageously provide a long flow path of carrier gas from ampoule inlet to outlet for transporting low vapor pressure precursors, such as liquid and / or solid source precursors. We understand low vapor pressure precursors to refer to materials that are not easily vaporized under atmospheric conditions. Low vapor pressure precursors typically have a vapor pressure of less than 10 Torr, and more typically less than 1 Torr. In some applications, a carrier gas is used to transport low vapor pressure materials from the ampoule to the reactor. Low vapor pressure materials typically require heat to increase their vapor pressure. A non-limiting list of illustrative precursors includes ZrCl₄, Y(EtCP)₃, HfCl₄, WCl₅, MoCl₅, In(CH₃)₃, and liquid SiI₄ and Mg(Cp)₂.

[0027] Flow paths with long, tortuous distances allow the carrier gas sufficient residence time to achieve partial to near-complete saturation through vaporization and / or sublimation and / or entrainment of precursors. As used herein, the term "tortuous path" refers to a flow path with multiple branches, curves, angles, bends, etc., which prevents flow along a straight path. In some embodiments, tortuous paths increase the residence time of the gas in the manifold, thereby improving concentration uniformity. The term "saturation" as used herein allows for varying degrees of saturation.

[0028] Some embodiments of this disclosure advantageously provide a bottom-fed ampoule configuration. Some embodiments advantageously provide an ampoule in which the depletion of the solid precursor does not affect the concentration of the saturated carrier gas.

[0029] Some embodiments provide apparatus and methods for heating low vapor pressure precursors in large-volume ampoules, including providing a way to effectively and uniformly heat the precursor. Some specific embodiments advantageously retain the low vapor pressure precursor, comprising solid precursor powder, within the cavity of the container, preventing its migration upstream or downstream to the control valve via the filter medium. Some embodiments advantageously control uneven depletion of the precursor. Some embodiments advantageously provide uniform distribution of the carrier gas along the entire surface of the precursor bed in a bottom-fed configuration. Embodiments herein provide dose-modified precursors.

[0030] In some embodiments, the ampoule includes a bottom wall having a plurality of elongated walls that define a tortuous path, such that the flow path is curved. Advantageously, one or more embodiments provide a flow path that is five to ten times longer than that of a conventional ampoule, particularly a solid-source sublimation container. The increased flow path allows for a longer residence time for the carrier gas and vaporization precursor chemicals to mix within the ampoule.

[0031] The ampoule disclosed herein comprises: a container defining a cavity configured to hold a precursor; an inlet and an outlet, both in fluid communication with the cavity; and a bottom wall having a serpentine bottom. The serpentine bottom comprises a plurality of elongated walls (also referred to as "serpentine paths") arranged to define a tortuous flow path, each of the elongated walls comprising a plurality of openings. The flow path and the plurality of openings define a flow path through which a carrier gas flows and contacts the vaporized or sublimated precursor.

[0032] The ampoule disclosed herein features a bottom-fed configuration that separates the precursor from the lower chamber within a sublimation bed defined by the filter medium. In this configuration, as the carrier gas passes over the filter medium, the precursor positioned above the filter medium is depleted, while the gas exchange zone below the filter medium maintains a constant volume. The gas exchange zone is configured to increase the residence time of the carrier gas and the vaporized precursor chemicals mixed within the ampoule.

[0033] The carrier gas passes through a sublimation bed in a gas exchange zone, where the precursor chemical mixes and flows with the carrier gas to form a saturated gas mixture of precursor and carrier gas. The carrier gas flows directly through a filter medium, thereby saturating the carrier gas with precursor particles. In some embodiments, the carrier gas flows through a tortuous path positioned in the gas exchange zone. The tortuous path and the gas exchange zone are configured to increase the duration of interaction between the carrier gas and the precursor chemical, thereby promoting an increase in the saturation of the vaporized precursor in the carrier gas.

[0034] Generally, the flow path described herein allows the carrier gas to flow around a series of elongated walls, which in one or more specific embodiments are nested concentric conduits with one or more open channels defining flow paths. The airflow changes direction between flow paths until it reaches the last flow path communicating with the outlet port. This change of direction also enhances the mixing of the vaporized and / or sublimated precursor with the carrier gas. The plurality of mutually offset openings allow the carrier gas to flow through the next flow path, thus forming a tortuous path. As the carrier gas flows from the inlet opening of the outermost elongated wall through the gas exchange zone and through the outlet opening of the innermost elongated wall, the pure carrier gas reaches partial saturation of the precursor chemical substance, and subsequently complete saturation, before exiting through the ampoule outlet.

[0035] The airflow mentioned herein includes carrier gas alone or a combination of carrier gas and entrained and / or vaporized and / or sublimated precursors. The flow path of the gas exchange zone described herein (e.g., Figures 1, 2, and 4) comprises a series of tubular or other shaped elongated walls having a plurality of mutually offset openings configured to define a flow channel, thereby obtaining the desired flow path. In some embodiments, as shown in Figure 4, each of the elongated walls includes an opening offset from the openings of adjacent elongated walls, configured to define a flow channel, thereby obtaining the desired flow path. In some embodiments, the plurality of openings are offset to ensure that no flow channel is bypassed. This disclosure refers to this configuration as an interchangeable "serpentine path" or "bent path."

[0036] Figures 1 through 3 illustrate schematic diagrams of ampoules containing semiconductor precursor materials. The ampoules have one or more individual or integrally integrated components, and the bottom wall of the ampoule includes a plurality of concentric elongated walls forming a curved path. In Figure 3, the bottom wall is a component separate from the outer cylindrical wall, allowing the ampoule to be filled with solid precursor, maintain the filter media, and be cleanable. Figure 4 illustrates a top view of the bottom wall according to one or more embodiments, showing a curved flow path configuration.

[0037] The ampoules described herein are suitable for use with semiconductor manufacturing materials, including reagents and precursors. In the illustrated embodiment, the precursor is suspended above a filter medium configured as a sublimation bed. A cavity for holding the solid precursor defines a general region above the filter medium. The general region below the filter is characterized as a gas exchange zone, in which carrier gas saturation occurs. Pure or unsaturated carrier gas is first transferred from an inlet channel formed between the inner and outer cylindrical walls to an opening in the outermost wall of a plurality of concentric elongated walls. The carrier gas is allowed to flow through the filter medium and through a tortuous path until it passes through the opening in the outermost wall of the plurality of concentric elongated walls. Subsequently, the carrier gas is discharged via an outlet conduit.

[0038] As shown in Figures 1 and 2, the ampoule 100 includes an outer cylindrical wall 110 having an inner surface 112 and an outer surface 114, and an inner cylindrical wall 120 having an inner surface 122 and an outer surface 124. The outer diameter ROD of the inner cylindrical wall 120 is smaller than the inner diameter RID of the outer cylindrical wall 110, thereby forming an inlet channel 130 between the inner cylindrical wall 120 and the outer cylindrical wall 110. In some embodiments, the outer cylindrical wall 110 and the inner cylindrical wall 120 are concentric, such that gas flowing through the inlet channel 130 flows from the inlet opening 176 to the bottom wall 140 of the ampoule 100. In some embodiments, the inlet opening 176 and the cap 170 are integral, as will be explained in further detail below. The inlet opening 176 is in fluid communication with the inlet channel 130, and the outlet opening 178 is in fluid communication with the outlet conduit 160.

[0039] The ampoule further includes a bottom wall 140 having a top surface 142. A plurality of concentric elongated walls 150 extend from the top surface 142, each of the concentric elongated walls 150 including a plurality of openings 152 offset from openings 152 of one or more adjacent walls 150. In some embodiments, each of the plurality of concentric elongated walls 150 includes a plurality of openings 152. In some embodiments, each of the plurality of concentric elongated walls 150 includes a single opening 152. As shown in Figure 4, the openings 152 of the plurality of concentric elongated walls 150 are offset from each other, causing gas to flow through a subsequent flow path of an adjacent concentric elongated wall 150, thereby creating a curved path. In some embodiments, each opening 152 of each of the plurality of concentric elongated walls 150 is offset from each other by 180 degrees.

[0040] Ampoule 100 further includes a cap 170, the bottom surface 172 of which contacts one or more of an outer cylindrical wall 110, an inner cylindrical wall 120, or an outlet conduit 160, thereby sealing the inlet passage 130 and the precursor cavity 102.

[0041] In some embodiments, the bottom surface of the cover 170 is integral with the outlet conduit 160. In some embodiments, the bottom surface of the cover 170 is integral with the inner cylindrical wall 120 and the outlet conduit 160. In such a configuration, the inner cylindrical wall 120 and the outlet conduit 160 may also be integral with the top wall 126, thereby connecting the inner cylindrical wall 120, the outlet conduit 160, and the top wall 126 to the bottom surface of the cover 170. In other embodiments, the inner cylindrical wall and the outlet conduit 160 are integral with the top wall 126, thereby forming a manifold that can be used with a conventional cover. The manifold including the inner cylindrical wall 120 and the outlet conduit 160 can be removed, maintained, and refilled with a precursor located in a precursor cavity 102 formed by the inner surface 122 of the inner cylindrical wall 120.

[0042] As described above, in some embodiments, the outer cylindrical wall 110 and the bottom wall 140 are integral. In some embodiments, as shown in Figure 3, the outer cylindrical wall 110 is removably secured to the top surface 142 of the bottom wall 140 by a plurality of fasteners 144, allowing bottom access and maintenance of the precursor cavity 102. The top surface 142 of the bottom wall 140 may further include a channel 146 for an O-ring, thereby forming a fluid seal between the top surface 142 of the bottom wall 140 and the bottom surface of the inner cylindrical wall 120.

[0043] In embodiments where the outer cylindrical wall 110 is a separate component from the cover 170, a flange 116 may extend outward from the outer surface 114 and from the top surface 118 of the outer cylindrical wall 110, and the flange 116 contacts the bottom surface of the cover 170. In such embodiments, the top surface 118 may further include a groove or channel 119 for an O-ring, thereby forming a fluid seal between the top surface 118 and the bottom surface of the cover 170. The cover 170 may be secured to the flange 116 using a plurality of fasteners 117 extending via the flange 116.

[0044] The cover 170 further includes an inlet opening 176 in fluid communication with the inlet passage 130 and an outlet opening 178 in fluid communication with the outlet conduit 160. As shown in Figure 2, the outlet conduit 160 has an inner surface and an outer surface, the outer surface of which defines an outer diameter RODO smaller than the inner diameter RID of the inner cylindrical wall 120, and the inner diameter defines the outlet passage 168 of the outlet conduit 160. The bottom surface 172 of the cover 170 contacts one or more of the outer cylindrical wall 110, the inner cylindrical wall 120, or the outlet conduit 160, thereby closing the inlet passage 130 and the precursor cavity 102, which is defined by the inner surface 122 of the inner cylindrical wall 120.

[0045] The precursor cavity 102 is sealed by a filter medium 180 in contact with the bottom end 127 of the inner cylindrical wall 120. As best illustrated in Figure 1, the bottom end 127 may include a notch to accommodate the filter medium 180. In some embodiments, the bottom end 127 further includes an inner beveled flange 128. In some embodiments, the filter medium 180 is secured between an outer retaining ring 182 and the bottom end 127 of the inner cylindrical wall 120, and the outer retaining ring 182 may be fastened to the bottom end 127 of the inner cylindrical wall 120 using a plurality of fasteners. In some embodiments, the outer retaining ring 182 may include threads that can be screwed into corresponding threads located on the bottom end 127 of the inner cylindrical wall 120. In some embodiments, the outer retaining ring 182 may be fastened or secured to the bottom end 127 of the inner cylindrical wall 120 by compression fitting, snap-fit ​​fitting, or the use of a C-clamp. In some embodiments, the filter medium 180 is fixed between the inner retaining ring 184 and the bottom surface of the outlet conduit 160.

[0046] The filter medium 180 is in the form of a flat disk, concentric with the outlet conduit 160. The filter medium 180 has porosity that allows vaporized substances to pass through, but prevents liquid or solid precursors from passing through. In some embodiments, the porosity of the filter medium 180 is in the range of 0.2 to 2000 micrometers.

[0047] The filter medium 180 is in contact with the top surface of each of the plurality of concentric elongated walls 150 that define the gas exchange zone 104. The gas exchange zone 104 is formed between the filter medium 180, the plurality of concentric elongated walls 150, and the bottom wall 140, and forms a tortuous path for gas to flow from the inlet channel 130 to the outlet conduit 160. The solid precursor is located above the filter medium 180 so that the depletion of the solid precursor does not cause a concentration change in the gas exchange zone 104.

[0048] Above the top surface of the filter medium 180, a low vapor pressure material (referred to as a "precursor" or "precursor material") remains above the filter medium 180 in the precursor cavity 102. The space above the material in the precursor cavity 102 is the inactive space of the ampoule 100. As the material is depleted, the volume of the inactive space increases, and since the volume of the gas exchange zone 104 remains constant, the concentration of saturated or partially saturated carrier gas in the gas exchange zone 104 is unaffected. The material may be a precursor for semiconductor manufacturing processes. In one or more embodiments, the material with low vapor pressure is a solid.

[0049] When the ampoule 100 is heated, the precursor vaporizes, forming a saturated vaporized precursor in the precursor cavity 102. As will be explained in more detail below, as the carrier gas passes over the filter medium 180 in the gas exchange zone 104, it mixes with the vaporized precursor material that has passed through the filter medium 180. Heating the ampoule 100 causes the material in close contact with or near the filter medium 180 to sublimate and diffuse throughout and through the filter medium 180. The sublimated material saturates the carrier gas after passing through the filter medium 180. In some embodiments, the unused space above the precursor material may contain gaseous sublimated material.

[0050] Because the material is fed through the filter medium 180 in the bottom-feed configuration, the depletion of the material will not cause a change in concentration in the gas exchange zone.

[0051] Inlet opening 176 is typically configured to allow connection to a gas source via suitable piping and valves, and may have a suitable threaded or sealed connection. In one or more embodiments, the gas source is a carrier gas; in one or more embodiments, the carrier gas is inert, such as N₂, Ar, or He; in some embodiments, the carrier gas is not inert, such as H₂, provided that the carrier gas does not react with the precursors in the container. Outlet opening 178 is typically configured to allow connection to a line (including suitable piping and valves) allowing gas flow (which may include entrained particles) leaving ampoule 100 to flow into the processing chamber (or other component). Inlet opening 176 and outlet opening 178 may have welded or threaded connections to allow connection to the gas line. Although the embodiments depict only one inlet and one outlet, specific applications require multiple inlets and outlets.

[0052] Each of the plurality of concentric elongated walls 150 includes a plurality of openings 152, thereby forming a tortuous flow path as illustrated by the arrows in the figure. The plurality of concentric elongated walls 150 and the plurality of openings 152 together form a labyrinthine or zigzag tortuous flow path, such that none of the plurality of openings 152 overlaps with another plurality of openings. For example, gas enters through the plurality of openings 152 of the outermost elongated wall 150a and exits through the plurality of openings 152 of the innermost elongated wall 150b. In other words, the plurality of openings 152 of any of the elongated walls 150 are offset from adjacent elongated walls 150. In some embodiments, as shown in Figure 4, each of the plurality of concentric elongated walls 150 includes only one opening 152.

[0053] In the diagram, the flow path is typically represented by a series of dashed arrows, illustrating a gas source "G" starting from inlet opening 176 and exiting from outlet opening 178. In some embodiments, as best illustrated in Figures 1 and 2, inlet opening 176 and outlet opening 178 are integral with the cover 170. The flow path is defined as follows: gas first enters through inlet opening 176 and flows around inlet channel 130. When the gas reaches bottom wall 140, it enters the outermost opening 152 of the outermost elongated wall 150a. Upon entering the outermost opening 152, the gas travels through the gas exchange zone 104 and the tortuous path formed by the plurality of concentric elongated walls 150 until it exits the tortuous path by passing through the innermost opening 152 of the innermost elongated wall 150b. The vaporization precursor is filtered via filter medium 180 to mix with the carrier gas as it passes through the gas exchange zone 104. The mixed gas exits via outlet conduit 160 and through outlet opening 178.

[0054] In some embodiments, a fine filter medium is disposed in the outlet opening 178 such that fine particles and / or droplets of the precursor do not exit the ampoule. In some embodiments, the fine filter medium may be any suitable material or configuration or size or media grade, thereby providing one or more of the following characteristics: resistance to prolonged exposure to the precursor, no introduction of a pressure drop that would impede the effective delivery of the precursor, pore size that inhibits and / or prevents fine particles and / or precursor droplets from exiting the ampoule to protect the outlet device, and flexibility that allows for slight sealing with a cylindrical shaft. The non-limiting illustrative porosity of the fine filter medium, measured by average pore size, may be greater than or equal to 0.1 micrometers to less than 100 micrometers and all values ​​and sub-ranges therebetween.

[0055] In some embodiments, ampoule 100 further includes one or more external heating elements disposed around ampoule 100. In some embodiments, internal heating elements are disposed and contact the bottom wall 140. In some embodiments, a cable heater is disposed and contact the bottom wall 140, such that the gas flowing in the gas exchange zone 104 is heated, thereby promoting the sublimation of the precursor material and the saturation of the carrier gas. One or more external heating elements are configured to vaporize the material in the precursor cavity 102, while the internal heating elements are configured to heat the elongated wall 150 to promote the sublimation of the vapor precursor and the carrier gas G throughout the gas exchange zone 104.

[0056] In some embodiments, each of the above-described structures that are in contact with each other further includes a circular channel for placing O-rings and other sealants. Specifically, in some embodiments, one or more O-rings are disposed between the filter medium 180 and the outer retaining ring 182, the inner retaining ring 184, and the inner cylindrical wall 120.

[0057] In some embodiments, the ampoule 100 is stored and transported inverted such that the material remains on the bottom surface 172 of the cap 170. In this configuration, damage to the filter medium 180 is prevented, and material migration through the filter medium 180 is also prevented.

[0058] In some embodiments, removable bolts are used to connect components through suitably shaped openings, which may have threaded portions to facilitate the connection of threaded bolts. The bolts can be removed for easy disassembly.

[0059] According to one or more embodiments, the plurality of openings in any embodiment are adapted to allow carrier gas to flow from one channel to another. The plurality of openings can take any suitable shape and / or configuration and / or location along an elongated wall to accommodate entrained and / or saturated carrier gas flow. The plurality of openings can be characterized as a plurality of orifices, grooves, or other shapes. In one or more embodiments, the size and shape of the plurality of openings are adjusted to provide different conductivity of the carrier gas along the longitudinal distance of the container. In one or more embodiments, the size of the plurality of openings is increased, thereby increasing the conductivity from the cap to the bottom wall of the ampoule.

[0060] In one or more embodiments, the plurality of openings are recesses located at the top of the elongated wall near the lid. In one or more embodiments, each of the plurality of openings spans a longitudinal distance (inclusive of all values ​​and subranges) greater than or equal to 1% to less than or equal to 100% of the length of the wall.

[0061] As the volume of the precursor cavity increases, the saturation of conventional ampoules decreases with the consumption of the solid precursor. However, in the described embodiment, since sublimation occurs in the sublimation cavity separated by the filter medium, the reduction of the solid precursor does not affect the saturation because the volume of the sublimation cavity remains constant. Furthermore, in conventional ampoules, gas flow is adjusted during processing to maintain a sufficient proportion as the precursor is consumed. However, in the described embodiment, since the volume of the sublimation cavity is constant, the gas flow can be kept constant.

[0062] We understand that the existence of entrances, exits, and channels / conduits is not restrictive; the number of ports, channels, and conduits can be selected based on spatial constraints and / or the characteristics of precursors and / or design needs.

[0063] In some embodiments, the gas flow across the filter medium and through the curved path is sufficient to entrain and / or vaporize and / or sublimate the precursor, without the need for foaming.

[0064] The equipment referred to herein may include thermocouples, mass flow meters, and pressure gauges to monitor process conditions. In one or more embodiments, a mass flow meter is provided to monitor the airflow into the inlet. In one or more embodiments, thermocouples are installed in the bottom wall of the container and at any heater locations disclosed above. In one or more embodiments, pressure gauges are provided on the inlet and / or outlet lines. The pressure range in the ampoules according to some embodiments is greater than or equal to 25 Torr and less than or equal to 150 Torr.

[0065] Throughout this specification, references to "one embodiment," "some embodiments," "one or more embodiments," or "an embodiment" mean that at least one embodiment of the invention includes a specific feature, structure, material, or characteristic described in connection with the embodiment. Therefore, the appearance of phrases such as "in one or more embodiments," "in some embodiments," "in one embodiment," or "in one embodiment" in multiple places throughout this specification does not necessarily refer to the same embodiment of the invention. Furthermore, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

[0066] Although the invention has been described with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. It will be apparent to those skilled in the art that modifications and alterations can be made to the methods and apparatus of the invention without departing from the spirit and scope of the invention. Therefore, the invention is intended to include modifications and alterations within the scope of the appended patent application and its equivalents.

[0067] 100: Ampoule 102: Precursor cavity 104: Gas Exchange Zone 110: Outer cylindrical wall 112: Inner surface 114: Outer surface 116: Flange 117: Fasteners 118: Top surface 119: Channel 120: Inner cylindrical wall 122: Inner surface 124: Outer surface 126: Top Wall 127: Bottom 128: Inner oblique flange 130: Entrance passage 140:Bottom wall 142: Top surface 144: Fasteners 146: Channel 150: wall 150a: Outermost slender wall 150b: Innermost slender wall 152: Opening 160: Outlet conduit 168: Export Channel 170: Lid 172: Bottom surface 176: Entrance opening 178: Exit opening 180: Filter media 182: Outer retaining ring 184: Inner retaining ring R ID: inner diameter ROD: Outer Diameter R ODO: Outer Diameter

[0068] Domestic storage information (please note in order of storage institution, date, and number) none Overseas storage information (please note in the order of storage country, institution, date, and number) none

Claims

1. An ampoule for a semiconductor precursor material, the ampoule comprising: an outer cylindrical wall having an inner surface and an outer surface; an inner cylindrical wall having an inner surface and an outer surface, the outer diameter of the inner cylindrical wall being smaller than an inner diameter of the outer cylindrical wall to form an inlet channel between the inner cylindrical wall and the outer cylindrical wall; a bottom wall having a top surface having a plurality of concentric elongated walls, each wall including an opening offset from the opening in an adjacent wall; an outlet conduit having an inner surface and an outer surface, the outer diameter of the outlet conduit being smaller than an inner diameter of the inner cylindrical wall to form a cavity, and the inner diameter of the outlet conduit defining an outlet channel; and a cap having a bottom surface contacting one or more of the outer cylindrical wall, the inner cylindrical wall, or the outlet conduit to close the inlet channel and the cavity, the cap having an inlet opening in fluid communication with the inlet channel and an outlet opening in fluid communication with the outlet conduit.

2. The ampoule as claimed in claim 1, further comprising a filter medium in contact with a top surface of each of the concentric elongated walls.

3. The ampoule as claimed in claim 2, wherein a gas exchange zone is formed between the filter medium, the plurality of concentric elongated walls and the bottom wall, the gas exchange zone forming a tortuous path for a gas to flow from the inlet channel to the outlet conduit.

4. An ampoule as claimed in claim 3, wherein a solid precursor is placed above the filter medium such that depletion of the solid precursor does not cause a change in concentration in the gas exchange zone.

5. The ampoule as claimed in claim 2, wherein the filter medium is fixed between an outer retaining ring and a bottom surface of the inner cylindrical wall.

6. The ampoule as claimed in claim 3, wherein the filter medium is fixed between an outer retaining ring and a bottom surface of the inner cylindrical wall.

7. The ampoule as claimed in claim 6, wherein the outer retaining ring is secured to the bottom surface of the inner cylindrical wall by a plurality of fasteners.

8. The ampoule as claimed in claim 2, wherein the filter medium is secured between an inner retaining ring and a bottom surface of the outlet conduit.

9. The ampoule as claimed in claim 1, wherein a bottom end of the inner cylindrical wall includes an inner oblique flange.

10. The ampoule as described in claim 1, wherein the outer cylindrical wall and the bottom wall are integral.

11. The ampoule as claimed in claim 1, wherein the outer cylindrical wall is removably secured to the bottom wall by a plurality of fasteners.

12. The ampoule as claimed in claim 1, wherein the outlet conduit is integral with the bottom surface of the cap.

13. The ampoule as claimed in claim 12, wherein the inner cylindrical wall and the bottom surface of the cap are integral.

14. The ampoule as claimed in claim 1 further includes a top wall integral with a top surface of the inner cylindrical wall, the top surface of the top wall being in contact with the bottom surface of the lid.

15. The ampoule as claimed in claim 1, wherein a top surface of the outer cylindrical wall includes a groove having an O-ring.

16. The ampoule as claimed in claim 1, wherein a flange extends outward from a top surface of the outer cylindrical wall and contacts the bottom surface of the cap.

17. An ampoule for a semiconductor precursor material, the ampoule comprising: an outer cylindrical wall having an inner surface and an outer surface; an inner cylindrical wall having an inner surface and an outer surface, the outer diameter of the inner cylindrical wall being smaller than an inner diameter of the outer cylindrical wall, thereby forming an inlet channel between the inner cylindrical wall and the outer cylindrical wall; a bottom wall having a top surface having a plurality of concentric elongated walls, each wall including an opening offset from the opening of an adjacent wall, the bottom wall having a diameter larger than the inner diameter of the outer cylindrical wall, the outer cylindrical wall being removably secured to the bottom wall by a plurality of fasteners; An outlet conduit having an inner surface and an outer surface, the outlet conduit having an outer diameter smaller than an inner diameter of an inner cylindrical wall to form a cavity, and the outlet conduit having an inner diameter defining an outlet channel; and a cover having a bottom surface that contacts one or more of the outer cylindrical wall, the inner cylindrical wall, or the outlet conduit to close the inlet channel and the cavity, the cover having an inlet opening in fluid communication with the inlet channel and an outlet opening in fluid communication with the outlet conduit.

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