A liquid level extension system, precursor delivery device, cylinder and method of use thereof

Abstract

The application discloses a liquid surface expansion system, a precursor gasification and conveying device, a steel cylinder and a gasification and conveying method. The system comprises: a liquid film extension assembly having vertically stacked extension members to form a thin layer of liquid film on each extension surface; a heat conduction member establishing a low thermal resistance heat conduction path from the outer wall of the container to the extension member; and an auxiliary gas-liquid contact member to extend residual liquid into a micro-liquid film by capillary action and force the carrier gas to produce disturbance. The vertical stacking configuration of the liquid film extension assembly effectively expands the heat exchange area by more than 25 times, the heat conduction member cooperates with the liquid film extension assembly to build a low thermal resistance heat conduction path from the external heat source to the heat exchange interface, and the three-dimensional porous structure of the auxiliary gas-liquid contact member effectively intercepts any possible micro-liquid droplets carried.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor integrated circuit manufacturing technology, and specifically relates to a high heat transfer type gas-liquid phase interface area expansion system, a precursor vaporization and conveying device, a gas cylinder, and a method of using the same. Background Technology

[0002] In advanced semiconductor manufacturing processes (3nm and below), metal-organic precursors such as cobalt (Co) and ruthenium (Ru) are widely used due to their excellent thin film properties. However, these precursors (such as CCTBA) have extremely low saturated vapor pressures (typically below 100 Pa) in the conventional process temperature range (70℃~90℃), resulting in very limited natural vaporization rates. Meanwhile, modern high-speed deposition processes place extremely stringent requirements on the quality of precursor vapor delivery: vapor saturation must reach over 99%, and concentration fluctuations must be controlled within 1%.

[0003] Traditional liquid precursor cylinders mainly rely on the following two vaporization methods: (a) The carrier gas is purged laterally above the static liquid surface inside the cylinder. The mass transfer area in this method is limited to the cross-sectional area of ​​the cylinder; for example, the liquid surface cross-sectional area of ​​a 1.2L cylinder is typically less than 80cm². 2 Under continuous suction conditions where the carrier gas flow rate reaches 500 sccm or more, the precursor vapor in the gas phase space is rapidly depleted, while the natural evaporation rate of the liquid surface is much lower than the suction and replacement rate of the carrier gas, resulting in a sharp drop in the outlet vapor saturation (usually only 40% to 50%), and the "feed collapse" effect occurs.

[0004] (ii) Bubbling is achieved by directly introducing carrier gas into the liquid through an immersion tube. While this method increases the gas-liquid contact area, it causes severe liquid surface fluctuations and bubble bursts, generating a large number of micron-sized droplets. Once these droplets enter the downstream gas supply lines and reaction chamber with the carrier gas, they will form irreversible microparticle defects on the wafer surface, severely damaging chip yield. In addition, the bubbling method also faces the problem of localized heat sinking due to the long heat transfer path.

[0005] In the prior art, Korean Patent KR100631719B1 discloses a scheme for setting an evaporator between a storage container and a reaction chamber, which evaporates the liquid precursor by setting a thermally conductive partition wall in the pipeline and combining it with an external heater. The main drawback of this scheme is that it requires an additional independent evaporator, which increases the system size, complexity and manufacturing cost, and the evaporator has a large dead volume, which is not conducive to the full utilization of the valuable precursor.

[0006] US Patent US20130333621A1 discloses an integrated deposition system, including a heating and exhaust system, a remote plasma generator, a processing chamber, a liquid delivery system, and a computer control module. These solutions focus on the overall integrated architecture of the deposition system, but do not propose specific structural improvements for expanding the gas-liquid interface area and enhancing heat transfer inside the gas cylinder, a key source component.

[0007] In addition, a solution has been proposed in this field to fill the inside of a steel cylinder entirely with sintered porous stainless steel media to increase the gas-liquid contact area. However, this solution has serious inherent drawbacks: the sintered porous media is extremely difficult to clean thoroughly and is prone to cross-contamination after repeated use; more seriously, in the later stages of the cylinder's use, the strong capillary action inside the porous media will firmly adsorb a large amount of liquid into the bottom pores, which cannot be effectively blown away by the carrier gas, resulting in a residual liquid rate as high as 8% to 15%, causing a large waste of valuable precursors worth thousands of dollars per cylinder.

[0008] In summary, how to achieve a significant expansion of the gas-liquid interface area, timely replenishment of latent heat of vaporization with low thermal resistance, and complete elimination of droplet entrainment at the outlet, all within the limited-volume precursor cylinder—the source component—with a simple mechanical structure, while also ensuring easy system cleaning and high precursor utilization, constitutes a long-standing and comprehensive technical challenge in this field. Summary of the Invention

[0009] To address the problems in related technologies, this invention proposes a high heat transfer type gas-liquid phase interface area expansion system, a precursor vaporization and conveying device, a gas cylinder, and a method for using the same, in order to overcome the aforementioned technical problems existing in the prior art.

[0010] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: This invention proposes a high heat transfer type gas-liquid phase interface area expansion system, configured in the inner cavity of a container for containing a liquid precursor, comprising: A liquid film spreading assembly includes at least two spreading members stacked vertically at intervals. The liquid film spreading assembly is configured to receive a liquid precursor introduced from above during the filling stage and to guide the liquid precursor downwards along the spreading surfaces of each spreading member by gravity, such that a thin liquid film remains on each spreading surface after filling. A heat-conducting component is disposed between the inner wall of the container and the liquid film extension assembly to establish a heat conduction path from the outside of the container to the extension assembly, so as to conduct external heat to the liquid film.

[0011] As a preferred technical solution, the liquid film stretching assembly includes: At least one first extension member having a through opening in a central region and a first extension surface surrounding the through opening, the liquid precursor being adapted to flow along the first extension surface toward the through opening and overflow downward through the through opening during filling; At least one second extension member having a closed central region, at least one overflow notch located on the outer periphery, and a second extension surface surrounding the central region, the liquid precursor being adapted to flow along the second extension surface from the central region toward the overflow notch and overflow downward through the overflow notch during filling; The first extension member and the second extension member are arranged alternately in the vertical direction, so that the radial flow direction of the liquid precursor on the two adjacent extension members is opposite.

[0012] As a preferred technical solution, a liquid film flattening structure is provided on the first extended surface and / or the second extended surface. The liquid film flattening structure is configured to apply a flattening force to the liquid precursor in a direction intersecting the radial flow direction, so as to maintain the thickness of the liquid film within a preset range.

[0013] As a preferred technical solution, the liquid film flattening structure includes at least one groove processed along the extended surface, the groove flattening and spreading the liquid in a direction transverse to the radial flow direction through the synergistic effect of capillary action and liquid surface tension.

[0014] As a preferred technical solution, the groove is a plurality of concentric annular micro-grooves with a depth of 0.1mm to 0.5mm, and the thickness of the flowing liquid film is maintained at 0.05mm to 0.2mm.

[0015] As a preferred technical solution, an auxiliary gas-liquid contact component is also included, which is disposed below the liquid film extension component. The auxiliary gas-liquid contact component has a three-dimensional porous structure and is configured to attach and extend residual liquid falling from above through capillary action to form an extended microliquid film.

[0016] As a preferred technical solution, the auxiliary gas-liquid contact component is a multi-layer structure composed of at least two overlapping porous sheets, wherein the porosity of each layer in the multi-layer structure is different.

[0017] As a preferred technical solution, the average pore diameter of the porous sheet in the upper layer of the multilayer structure is greater than the average pore diameter of the porous sheet in the lower layer.

[0018] As a preferred technical solution, the average pore diameter of the porous sheet located in the upper layer is 1.5mm to 2.5mm, and the average pore diameter of the porous sheet located in the lower layer is 0.2mm to 0.5mm.

[0019] As a preferred technical solution, the porous sheet is selected from at least one of woven metal wire mesh, sintered metal powder mesh, and perforated metal plate mesh.

[0020] As a preferred technical solution, the heat-conducting component includes at least three ribs spaced apart circumferentially, each rib having a radially outer end that fits against the inner wall of the container and a radially inner end that connects to the liquid film extension assembly.

[0021] As a preferred technical solution, the material of the rib is selected from at least one of stainless steel, Hastelloy and copper-based alloy, and its overall thermal conductivity is not less than 20 W / (m·K).

[0022] As a preferred technical solution, the cross-sectional thickness of the rib gradually decreases from the radial outer end to the radial inner end.

[0023] The present invention also proposes a precursor vaporization and conveying device, disposed in the inner cavity of a container for containing a liquid precursor, comprising: the liquid level expansion system described above.

[0024] As a preferred technical solution, it further includes: a swirl inlet component, which is installed at the inlet of the container to convert the introduced carrier gas into a circumferential rotating jet, so that the carrier gas flows sequentially through the liquid film on each stage of the extended surface and the extended micro-liquid film on the auxiliary gas-liquid contact component in a tangential sweeping manner.

[0025] As a preferred technical solution, the swirl inlet component has at least one outlet channel that is inclined at an angle to the vertical axis, the inclination angle being 15° to 60°.

[0026] The present invention also proposes a semiconductor precursor cylinder, comprising: The bottle body has an internal cavity for containing the liquid precursor; The aforementioned liquid level expansion system is installed inside the cavity; and A heating device is disposed outside the bottle body for heating the bottle body, and the heat generated by the heating device is at least partially conducted to the liquid film via the heat-conducting member.

[0027] As a preferred technical solution, the heating device is a resistance heating sleeve or an induction heating sleeve fitted onto the outer wall of the bottle.

[0028] This invention also proposes a method for transporting a liquid precursor vaporization, applied to the inner cavity of a container, the method comprising the following steps: Filling stage: The liquid precursor is introduced from the upper region of the inner cavity and spreads downwards step by step along at least two vertically spaced extended surfaces under gravity, so that a thin liquid film is retained on each of the extended surfaces after filling. Vaporization operation stage: Through the heat conduction path thermally coupled between the inner wall of the container and the extended surface, heat conducted from the outside of the container is supplied to the liquid film on each of the extended surfaces to compensate for the heat required for the vaporization of the liquid on the liquid film. The carrier gas is introduced into the inner cavity in the form of a circumferential rotating jet, and flows sequentially through the liquid film on each stage of the extended surface in a tangential sweeping manner, so as to carry the vaporized precursor vapor out of the outlet of the inner cavity.

[0029] Based on the above technical solution, compared with the prior art, the present invention has at least the following beneficial effects: (1) Through the vertical stacked configuration of the liquid film extension component, the liquid is spread on the surface of each extension component by gravity during the filling stage, and the effective mass exchange area is expanded by more than 25 times after filling.

[0030] (2) The synergistic construction of the heat-conducting component and the liquid film extension component creates a low thermal resistance heat conduction path from the external heat source directly to the heat exchange interface. Combined with the extremely small internal thermal resistance of the liquid film due to the micron-level liquid film thickness, the heat exchange interface temperature drop of <0.5℃ is achieved.

[0031] (3) The circumferential cyclone generated by the swirling air intake component interacts with the liquid film in a tangential sweeping manner, which avoids the impact and damage of the liquid surface by the direct airflow from the mechanism level; at the same time, the three-dimensional porous structure of the auxiliary gas-liquid contact component can effectively intercept any micro-droplets that may be carried.

[0032] (4) The stacked disc structure of the liquid film extension component has excellent self-drainage characteristics (the liquid is discharged downwards by gravity). Combined with the capillary micro-liquid film maintenance ability of the auxiliary gas-liquid contact component and the inclined drainage design at the bottom of the container, the residual liquid rate at the end of the life of the steel cylinder can be reduced to less than 0.2%, and the corresponding precursor utilization rate is ≥99.8%.

[0033] (5) The liquid film extension component and the auxiliary gas-liquid contact component are detachable, which makes it easy to remove the whole component from the container and perform high-pressure backflushing or ultrasonic cleaning. This effectively avoids cross-contamination between multiple uses and overcomes the inherent defect of existing sintered porous media solutions that are difficult to clean.

[0034] (6) In this invention, the size of the gas-liquid phase interface area is mainly determined by the number of stages of the liquid film extension component and the area of ​​a single extension surface. The thermal compensation capability is mainly determined by the thermal conductivity and cross-sectional area of ​​the heat-conducting component. Both can be configured and optimized independently at the design and manufacturing level. Therefore, the parameters at each stage can be flexibly customized according to the vapor pressure characteristics of different precursors and the target process flow rate, and it has a wide range of process adaptability. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the embodiments of the invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] The present invention Figure 1 This is a schematic diagram of a high heat transfer type gas-liquid phase interface area expansion system. The present invention Figure 2 A schematic diagram of the structure of the first extension component of a high heat transfer type gas-liquid phase interface area expansion system; The present invention Figure 3 A schematic diagram of the structure of the second extension component of a high heat transfer type gas-liquid phase interface area expansion system; The present invention Figure 4 A schematic diagram of the cross-sectional structure of an extension component for a high heat transfer type gas-liquid phase interface area expansion system; The present invention Figure 5 A schematic diagram of the structure of an auxiliary gas-liquid contact component in a high heat transfer type gas-liquid phase interface area expansion system; The present invention Figure 6 A schematic diagram of the structure of a finned heat-conducting component in a high-heat-transfer gas-liquid phase interface area expansion system; The present invention Figure 7 This is a schematic diagram of the swirl inlet component of a precursor gasification and conveying device.

[0037] Wherein: 1-Liquid film extension component, 2-Heat-conducting component, 3-Auxiliary gas-liquid contact component, 4-Swirl inlet component, 5-Carrier gas inlet, 6-Steam outlet, 7-Heating device, 10-Extension component, 20-Liquid film, 30-Extension microfilm, 101-First extension component, 1011-First extension surface, 102-Second extension component, 1021-Second extension surface, 1022-Overflow notch, 103-Liquid film flattening structure, 1031-Groove, 201-Rib, 301-Porous sheet. Detailed Implementation

[0038] The technical solutions of the embodiments of the invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the invention, and not all embodiments. Based on the embodiments of the invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the invention.

[0039] In the description of this invention, it should be understood that the terms "opening", "upper", "lower", "top", "middle", "inner", etc., which indicate orientation or positional relationship, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the invention.

[0040] refer to Figure 1-7 As shown, the present invention proposes a high heat transfer gas-liquid interfacial area expansion system, which is configured in the inner cavity of a container 4 for containing a liquid precursor, including: a liquid film extension component 1, a heat-conducting component 2, and an auxiliary gas-liquid contact component 3.

[0041] The liquid film spreading assembly 1 of the present invention includes at least two spreading members 10 stacked vertically at intervals. A thin liquid film 20 is retained on the spreading surface of the spreading members 10. Specifically, during the filling stage, a liquid precursor introduced from above is received, and the liquid precursor is guided by gravity to spread downwards along the spreading surface of each spreading member 10, so that a thin liquid film 20 is retained on each spreading surface after filling.

[0042] The auxiliary gas-liquid contact component 3 of the present invention is disposed below the liquid film extension component 1. The auxiliary gas-liquid contact component 3 has a three-dimensional porous structure and is configured to attach and extend residual liquid falling from above through capillary action, and form an extended microfilm 30.

[0043] The heat-conducting component 2 of the present invention is disposed between the inner wall of the container 4 and the liquid film extension component 1 to establish a heat conduction path from the outside of the container 4 to the extension component 10, so as to conduct external heat to the liquid film 20. The heat-conducting component 2 is also disposed below the auxiliary gas-liquid contact component 3 to heat the extended microfilm 30.

[0044] The liquid film stretching assembly 1 of the present invention includes: At least one first extension member 101 has a through opening in a central region and a first extension surface 1011 surrounding the through opening, wherein the liquid precursor is adapted to flow along the first extension surface 1011 toward the through opening and overflow downward through the through opening during filling. At least one second extension member 102 has a closed central region, at least one overflow notch 1022 located on the outer periphery, and a second extension surface 1021 surrounding the central region, wherein the liquid precursor is adapted to flow along the second extension surface 1021 from the central region toward the overflow notch 1022 and overflow downward through the overflow notch 1022 during the filling process. The first extension member 101 and the second extension member 102 are arranged alternately in the vertical direction, so that the radial flow direction of the liquid precursor on the two adjacent extension members 10 is opposite.

[0045] A liquid film flattening structure 103 is provided on the first extended surface 1011 and / or the second extended surface 1021 of the present invention. The liquid film flattening structure 103 is configured to apply a flattening force to the liquid precursor in a direction intersecting the radial flow direction to maintain the thickness of the liquid film 20 within a preset range.

[0046] The liquid film flattening structure 103 of the present invention includes at least one groove 1031 processed along the extended surface. The groove 1031 flattens and spreads the liquid in a direction transverse to the radial flow direction through the synergistic effect of capillary action and liquid surface tension. The groove 1031 consists of multiple concentric annular micro-grooves with a depth of 0.1 mm to 0.5 mm, and the thickness of the liquid film 20 is maintained at 0.05 mm to 0.2 mm.

[0047] The auxiliary gas-liquid contact component 3 of the present invention is a multilayer structure composed of at least two overlapping porous sheets 301, wherein the porosity of each layer in the multilayer structure is different. The average pore size of the porous sheet 301 in the upper layer is larger than that of the porous sheet 301 in the lower layer. Specifically, the average pore size of the porous sheet 301 in the upper layer is 1.5 mm to 2.5 mm, and the average pore size of the porous sheet 301 in the lower layer is 0.2 mm to 0.5 mm.

[0048] The porous sheet 301 of the present invention is selected from at least one of woven metal wire mesh, sintered metal powder mesh and perforated metal plate mesh.

[0049] The heat-conducting member 2 of the present invention includes at least three ribs 201 spaced apart circumferentially. Each rib 201 has a radially outer end that fits against the inner wall of the container 4 and a radially inner end that connects to the liquid film extension assembly 1. The material of the ribs 201 is selected from at least one of stainless steel, Hastelloy, and copper-based alloys, and its overall thermal conductivity is not less than 20 W / (m·K).

[0050] It is worth noting that the cross-sectional thickness of the rib 201 gradually decreases from the radial outer end to the radial inner end.

[0051] The present invention also proposes a precursor vaporization and conveying device, which is disposed in the inner cavity of a container 4 for containing a liquid precursor, including: a front liquid level expansion system.

[0052] The precursor vaporization and conveying device of the present invention further includes: a swirl inlet component 4, which is installed at the inlet of the container 4, for converting the introduced carrier gas into a circumferential rotating jet, so that the carrier gas flows sequentially through the liquid film 20 on each stage of the extended surface and the extended microfilm 30 on the auxiliary gas-liquid contact component 3 in a tangential sweeping manner.

[0053] The swirl intake component 4 of the present invention has at least one outlet channel that is inclined at an angle to the vertical axis, the inclination angle being 15° to 60°.

[0054] The following describes a semiconductor precursor cylinder with an integrated gas-liquid phase interface area expansion system according to a specific embodiment of the present invention.

[0055] Example 1 (a) Bottle structure The cylinder is a 1.2L stainless steel pressure vessel 4, with an inner cavity for accommodating the liquid precursor. This invention is not limited to the 1.2L size and can be applied to cylinders of other sizes; this embodiment uses a 1.2L stainless steel pressure vessel 4 as an example. The inner diameter of the cavity is 100 mm, and the effective internal height is approximately mm. The top of the cylinder is equipped with a carrier gas inlet 5 and a steam outlet 6. The bottom wall of the cavity slopes towards the lowest point of the central area at an angle of approximately 3°, forming a sloping bottom structure for drainage. This allows residual liquid precursors to naturally collect at the lowest point under gravity during later stages of cylinder use, facilitating full utilization by the vaporization system. A heating device 7 in the form of a resistance heating jacket is tightly fitted onto the outer wall of the cylinder. Its rated heating power is 300W, and it is equipped with a PID temperature controller to precisely maintain the cylinder temperature within ±0.5℃ of the set value.

[0056] (II) Liquid film stretching assembly 1 The liquid film extension assembly 1 is installed in the upper middle region of the inner cavity and consists of three levels of extension members 10 stacked vertically at intervals. From top to bottom, they are: top layer first extension member 101, middle layer second extension member 102, and bottom layer first extension member 101, with a vertical spacing of 25 mm between adjacent levels.

[0057] The first extension member 101 of the top and bottom layers is a circular disc with a diameter of 90 mm. A circular through-hole with a diameter of 15 mm is provided at the geometric center of the disc for downward overflow of liquid. An annular baffle with a height of 3 mm is provided around the outer perimeter of the disc to prevent liquid from overflowing directly from the edge of the disc, thereby forcing all liquid to complete a full radial flow path along the disc before overflowing downward through the central through-hole.

[0058] The second extension member 102 in the middle layer is a circular disc with a diameter of 85 mm. The central area is a closed structure, and eight rectangular overflow gaps 1022 are evenly distributed around the outer perimeter of the disc. After the liquid reaches the central area of ​​the second extension member 102, it flows radially outward evenly along the disc surface under the drive of gravity, and finally overflows downward through these eight overflow gaps 1022 to the first extension member 101 at the bottom layer.

[0059] The alternating arrangement of the first extension member 101 and the second extension member 102 makes the radial flow direction of the liquid precursor on the three-stage extension member 10 sequentially: top layer (outer → inner) → middle layer (inner → outer) → bottom layer (outer → inner), forming a reciprocating flow path, which extends the total flow path length of the liquid on the three-stage disk surface to about 270 mm (about 3 times the diameter of a single-stage disk surface), and significantly increases the contact time between the liquid and the carrier gas.

[0060] On the upper surface (i.e., the extended surface) of each stage of the extension member 10, a liquid film flattening structure 103 is formed by precision machining. Specifically, the liquid film flattening structure 103 consists of multiple annular grooves 1031 arranged concentrically from the center of the disk surface outwards. In this embodiment, a total of 20 concentric grooves 1031 are machined. Each groove 1031 has a U-shaped cross-section, a groove depth of 0.25 mm, a groove opening width of 0.5 mm, and a spacing of 2 mm between two adjacent grooves 1031. The selection of the depth and spacing of the grooves 1031 is based on the following physical considerations: the depth of the grooves 1031 (0.25 mm) must be significantly greater than the expected thickness of the liquid film 20 (approximately 0.1 mm) to provide sufficient capillary driving force, but not so deep that the liquid film 20 cannot completely cover the bottom of the groove when the liquid flow rate is low; the spacing must allow the “capillary flattening effect zone” between adjacent grooves to overlap, thereby forming a continuous flattening effect on the entire disk surface and ensuring the radial uniformity of the thickness of the liquid film 20.

[0061] (III) Auxiliary gas-liquid contact components 3 The auxiliary gas-liquid contact component 3 is located 40 mm below the bottom first extension component 101, above the preset lowest operating liquid level in the inner cavity. This component is suspended and fixed by the radial inner ends of six sets of heat-conducting fins 201.

[0062] The auxiliary gas-liquid contact component 3 is a multi-layer structure composed of multiple overlapping stainless steel wire meshes. Each layer of mesh is circular in shape, matching the contour of the inner wall of the bottle, with a diameter of 95 mm, and the mesh surface is horizontally tensioned.

[0063] The uppermost porous sheet 301 is made of 316L stainless steel wire woven in a plain weave. The wire diameter is 0.5 mm, the mesh is square with an average aperture of 2.0 mm, and the porosity is approximately 64%. The physical functions of this layer are: (a) to capture large droplets (typically 0.5 mm to 3 mm in diameter) falling from the central through-hole of the uppermost extension member 10, which are broken and extended after impacting the wire; (b) due to the large aperture (2.0 mm), the pressure drop applied to the carrier gas flow is minimal (approximately 5 Pa), and the system's airflow resistance is not significantly increased.

[0064] The bottommost porous sheet 301 is made of 316L stainless steel wire twill-woven with a wire diameter of 0.15 mm and square mesh openings with an average pore size of 0.3 mm and an open area ratio of approximately 38%. The physical functions of this layer are: (a) to utilize the strong capillary pressure generated by its small pore size (estimated according to the Young-Laplace equation, the capillary pressure corresponding to a pore size of 0.3 mm for a fully wetted wire surface is approximately 480 Pa) to firmly bind the liquid seeping down from the upper layer inside the mesh openings, forming a meniscus-shaped micro-liquid film 20 around each wire. The total surface area of ​​the micro-liquid film 20 is estimated to be approximately 3 to 5 times the projected area of ​​the mesh structure; (b) the small-pore mesh surface applies moderate flow resistance to the carrier gas passing through it, forcing the carrier gas to undergo multiple directional deflections (serpentine flow) when passing through the mesh surface, thereby generating turbulent flow that deviates from laminar flow and significantly enhancing gas-liquid convection mass transfer.

[0065] The intermediate porous sheet 301 is made of 316L stainless steel wire woven in a twill pattern, with the wire diameter gradually decreasing from top to bottom. The spacing between the two mesh layers is 5 mm, which provides space for the breakup and redistribution of large droplets in the upper layer.

[0066] (iv) Thermal conductive components 2 The heat-conducting component 2 consists of six groups of highly thermally conductive fins 201 evenly spaced (60° intervals) along the circumference. Each group of fins 201 is a flat plate made of 316L stainless steel with a thermal conductivity of 22 W / (m·K) and a density of approximately 8.0 g / cm³.

[0067] The geometry of each set of ribs 201 is as follows: the outer radial end (the end that fits against the inner wall of the bottle) has a cross-sectional thickness of 4 mm and a width of 15 mm; the inner radial end (the end that connects to the liquid film extension component 1 / auxiliary gas-liquid contact component 3) has a cross-sectional thickness that gradually decreases to 1.5 mm and a width of 10 mm. This variable cross-section design, which gradually thins from the outside to the inside, has the following engineering advantages: (a) it maintains sufficient thermal conductivity cross-sectional area at the outer radial end to efficiently absorb the heat conducted by the bottle wall; (b) it reduces the mass at the inner end, reducing the cantilever load on the central support component; and (c) the heat flux density along the variable cross-section path gradually increases from the outside to the inside, which matches the physical law that the heat flux demand is more concentrated closer to the surface of the liquid film 20.

[0068] The radial outer end of each rib 201 is sealed to the inner wall of the bottle by laser welding to ensure maximum metal-to-metal contact thermal conductivity and minimum contact thermal resistance. The radial inner end of each rib 201 is provided with three mounting holes, which are detachably fixed to the outer periphery of the three-stage extension member 10 and the mesh frame of the auxiliary gas-liquid contact member 3 by M3 stainless steel bolts.

[0069] (v) Swirl intake component 4 The swirling air inlet component 4 is installed inside the carrier gas inlet 5 at the top of the bottle. Its main body is a cylindrical block with a diameter of 18 mm, and it has 6 tangential air outlet channels machined inside at a 30° angle to the vertical axis. Each channel has a diameter of 2 mm. When the carrier gas enters from the top at a certain pressure (usually 0.1 to 0.5 MPa gauge pressure), it is ejected through these 6 tangential channels, forming a circumferential rotating jet in the upper gas phase space of the bottle. This circumferential swirling air gradually diffuses as it propagates downwards, uniformly sweeping across the liquid film 20 on the surface of each stage of the extension components 10.

[0070] (vi) System assembly and disassembly In this embodiment, the liquid film extension component 1, the auxiliary gas-liquid contact component 3, and the heat-conducting component 2 are detachably connected. High-pressure (5-10 MPa) deionized water or organic solvents (such as isopropanol) can be used to backwash the surface of the extension component 10 and the auxiliary gas-liquid contact component 3 from all directions. With the assistance of an ultrasonic cleaning tank, deposits can be thoroughly removed, eliminating the cleaning dead zones and coking problems present in sintered porous media solutions.

[0071] (vii) Work process The following describes in detail the complete working process of this embodiment under standard operating conditions: A. Filling Stage – Liquid Film Spreading and Formation The liquid precursor (in this embodiment, CCTBA cobalt precursor is used, with a saturated vapor pressure of approximately 125 Pa at 80°C) is introduced from outside the cylinder during its first use or refilling and drips onto the vicinity of the central region of the first extension member 101 at the top layer under gravity. Driven by the radial component of gravity along the disk surface, the liquid spreads and flows outward from the center along the disk surface. When the liquid flows through the concentric microgrooves on the disk surface, the groove walls exert upward and lateral capillary forces on the liquid, which, in conjunction with the surface tension of the liquid itself, uniformly flatten the liquid that might converge into a stream due to surface tension contraction along the transverse (circumferential) direction, thereby forming a uniformly spread flowing liquid film 20 with a thickness of approximately 0.10 mm on the disk surface.

[0072] After the liquid on the top layer first extension member 101 flows to the outer periphery of the disk, it is blocked by the annular baffle. The liquid briefly accumulates inside the baffle and then turns, overflowing downwards through the through-hole at the center of the disk surface and falling into the central closed area of ​​the middle layer second extension member 102. The liquid reaching the second extension member 102 continues to spread radially outwards from the center of the disk surface under the drive of gravity. It also maintains a uniform liquid film thickness of about 0.10 mm under the flattening effect of the concentric micro-grooves, and finally overflows downwards through the eight outer peripheral overflow gaps 1022 to the bottom layer first extension member 101. The bottom layer first extension member 101 repeats the same "outer → inner" spreading path as the top layer, and finally the remaining liquid falls downwards from its central through-hole into the auxiliary gas-liquid contact member 3.

[0073] The residual liquid is first captured by the upper large-pore metal mesh, and the coarse droplets are broken and extended after hitting the metal wires; some of the liquid continues to seep into the lower small-pore metal mesh under the action of gravity, and is firmly adsorbed by its strong capillary force, forming a meniscus-shaped extended microfilm 30 around each metal wire.

[0074] After filling, the liquid remains as a thin liquid film 20 on the surface of each extension member 10 and inside the porous member. The thickness of the liquid film 20 is determined by the geometric parameters of the liquid film flattening structure 103 and the surface tension of the liquid. At this time, the liquid film 20 on each extension member 10 is in a static state.

[0075] B. Gasification Operation Stage – Carrier Gas Sweeping Gasification After filling is completed and the system reaches thermal equilibrium (the heating device 7400 precisely maintains the bottle temperature at 80℃±0.5℃), the vaporization operation stage begins.

[0076] High-purity Ar carrier gas is introduced from the top carrier gas inlet 5 at a flow rate of 500 sccm and a gauge pressure of 0.2 MPa. The carrier gas is converted into a circumferential rotating jet through the six tangential outlet channels of the swirling inlet component 4. As this circumferential swirling gas propagates downward, it flows sequentially in a tangential sweeping manner through: the static liquid film 20 of the top first extension component 101 → the static liquid film 20 of the middle second extension component 102 → the static liquid film 20 of the bottom first extension component 101 → the upper large-aperture metal mesh of the auxiliary gas-liquid contact component 3 → the lower small-aperture metal mesh. At each gas-liquid contact interface, the partial pressure of the precursor vapor in the carrier gas is much lower than the saturated vapor pressure at that temperature. According to Fick's diffusion law, precursor molecules continuously evaporate / desorb from the free surface of the liquid film 20 and enter the carrier gas flow body. Since the liquid film 20 on each extension member 10 is in a static state and its thickness is only about 0.1 mm, the molecular diffusion path inside the liquid film 20 is extremely short, and the molecular concentration on the surface of the liquid film 20 is always close to the bulk equilibrium concentration at this temperature, so that the evaporation driving force is maintained at a high level.

[0077] During the entire vaporization process, the liquid precursor molecules need to absorb latent heat of vaporization (approximately 40 kJ / mol for CCTBA) to transform from the liquid phase to the gas phase. This heat is supplied by the external heating device 7: heat is transferred via the stainless steel wall of the bottle → the radial outer end of the heat-conducting fin 201 → internal heat conduction of the heat-conducting fin 201 → the radial inner end of the heat-conducting fin 201 → the extension member 10 / auxiliary gas-liquid contact member 3 → liquid film 20 / micro-liquid film 20. Due to the high overall thermal conductivity of the heat-conducting fin 201 (22 W / (m·K)) and ample heat transfer cross-sectional area, the thermal resistance along the entire heat conduction path is extremely low. Simultaneously, the liquid film 20 is only about 0.1 mm thick, meaning that heat only needs to penetrate about 0.1 mm of liquid layer to reach the free surface from the bottom of the liquid film 20 (the contact surface with the extension member 10), resulting in minimal thermal resistance within the liquid film 20. Actual measurement data shows that the maximum local temperature drop at the heat exchange interface under standard operating conditions is only 0.22℃, corresponding to a saturated vapor pressure drop of less than 1%. As vaporization proceeds, the liquid in the liquid film 20 is gradually consumed, and the film thickness slowly decreases until it needs to be refilled.

[0078] After the above-mentioned multi-stage gas-liquid contact, the carrier gas, which has been carrying saturated precursor vapor, is discharged from the vapor outlet 6 at the top of the bottle under the combined action of buoyancy and downstream suction pressure difference, and is transported to the downstream ALD or CVD reaction chamber through the insulated gas pipeline.

[0079] Example 2 (Two-level simplified configuration) The main difference between this embodiment and Embodiment 1 is that the liquid film extension assembly 1 consists of only two stages of extension members 10—a top-layer first extension member 101 (outer to inner flow) and a bottom-layer second extension member 102 (inner to outer flow). The bottom-layer first extension member 101 in Embodiment 1 is omitted. The auxiliary gas-liquid contact member 3 uses only a single piece of medium-diameter stainless steel wire mesh with a pore size of 0.5 mm. The operating temperature of the heating device 7 is set to 85°C. The remaining structural parameters and process conditions are consistent with those of Embodiment 1.

[0080] This embodiment is applicable to precursors with relatively high vapor pressure (e.g., saturated vapor pressure ≥ 500 Pa at 85°C) or process scenarios with low carrier gas flow requirements (≤ 200 sccm). Due to the reduction in the number of stages of the extension member 10, the system's manufacturing cost and pressure drop are both reduced, but the corresponding maximum equivalent exchange area is reduced to approximately 1400 cm². 2 .

[0081] Example 3 (Level 5 High-Capacity Configuration) The main difference between this embodiment and Embodiment 1 is that the liquid film extension component 110 is expanded to five stages, using an alternating arrangement of "first extension component 101 - second extension component 102 - first extension component 101 - second extension component 102 - first extension component 101", with each stage having a disk diameter of 90 mm and a stage spacing of 20 mm. The auxiliary gas-liquid contact component 3 uses a three-layer gradient aperture stainless steel wire mesh, with average apertures of 2.0 mm, 0.8 mm, and 0.2 mm from top to bottom. The number of heat-conducting fins 201 is increased to 8 sets (45° intervals). The rated power of the heating device 7400 is increased to 500W to meet the thermal compensation requirements of the larger heat exchange area.

[0082] This embodiment is applicable to extreme process scenarios involving ultra-low vapor pressure precursors (e.g., saturated vapor pressure <50 Pa at 80°C) or ultra-high carrier gas flow rates (≥3000 sccm). The total extended surface area of ​​the five-stage extension member 10 is calculated to be approximately 3500 cm². 2 This is sufficient to support a precursor vapor saturation of ≥99% at a carrier gas flow rate of 3000 sccm.

[0083] Example 4 (Variant of copper-based nickel-plated alloy thermal conductive fin 201) The main difference between this embodiment and Embodiment 1 is that the material of the thermally conductive fin 201 is replaced with a copper-based nickel-plated alloy (specifically, a 5μm thick nickel-phosphorus alloy layer is chemically plated onto the surface of an oxygen-free copper substrate). Its overall thermal conductivity is approximately 180 W / (m·K), about eight times that of 316L stainless steel. The nickel plating layer of the copper-based nickel-plated alloy ensures chemical compatibility with the liquid precursor (preventing the catalytic decomposition of the precursor by copper), while the copper substrate provides excellent thermal conductivity. All other structural parameters and process conditions remain consistent with Embodiment 1.

[0084] By adopting copper-based nickel-plated alloy fins 201, the maximum local temperature drop at the heat exchange interface is further reduced to below 0.05℃ under the same heating power. The system's response speed to power fluctuations of the heating device 7 is significantly accelerated, and it is expected to achieve more precise real-time control of precursor vapor concentration.

[0085] Comparative Example 1 (Conventional Static Liquid Level Purging of Steel Cylinders) A standard 1.2L stainless steel cylinder without any internal expansion structures is used. The cylinder is filled with CCTBA liquid precursor to the normal operating level (approximately 80 mm from the bottom). Carrier gas Ar is introduced directly into the cylinder's vapor space at a flow rate of 500 sccm from the top inlet, purging horizontally above the static liquid level before exiting from the outlet. The heating mantle is set to operate at 80°C.

[0086] Comparative Example 2 (Bubbling Gas Cylinder) A standard 1.2L bubbling-type steel cylinder is used. The cylinder is filled with CCTBA liquid precursor to the normal operating level. Carrier gas Ar is introduced into the liquid at a flow rate of 500 sccm through a 3 mm inner diameter stainless steel submersible tube, vertically inserted from the top to approximately 40 mm below the liquid surface, using a bubbling method. The carrier gas carrying the precursor vapor is discharged from the gas phase space above the liquid surface through the outlet. The heating mantle is set to operate at 80°C.

[0087] Comparison of overall performance of Examples 1-4 and Comparative Examples 1-2 Steady-state gasification performance tests were conducted on the above embodiments and comparative examples. All tests were performed under the same external conditions (ambient temperature 25℃, outlet pipeline insulation 80℃). After the system reached thermal and mass equilibrium (usually requiring 30 minutes), data were continuously collected for 120 minutes and the average value was taken. The test results are summarized in the table below: ; The following conclusions can be drawn from the data in the table above: (1) A significant improvement in mass transfer performance. The effective mass transfer area of ​​Comparative Example 1 (conventional static purging) is only 78.5 cm² of the cylinder cross-section. 2At a carrier gas flow rate of 500 sccm, the precursor vapor saturation is only 44.3%, far from meeting the requirements of high-speed deposition processes. Embodiment 1 of this invention, through the synergistic effect of the three-stage extension member 10 and the auxiliary gas-liquid contact member 3, increases the effective mass exchange area to 2100 cm². 2 (Approximately 27 times), corresponding to a surge in precursor vapor saturation to 99.6%. Example 3 employs a five-stage extension member 10 configuration, further expanding the heat exchange area to 3500 cm². 2 The saturation reaches the thermodynamic limit (100.0%) at that temperature. Even in the simplest two-stage configuration (Example 2), the exchange area reaches 1400 cm². 2 (Approximately 18 times), with saturation maintained at 94.6%. These data fully demonstrate the significant and scalable effect of the "vertical stacking" configuration of the liquid film extension component 1 on expanding the gas-liquid interface area.

[0088] (2) The decisive contribution of the material of the heat-conducting component 2 to the phase change efficiency. Comparing Example 1 and Example 4: Example 4 uses copper-based nickel-plated alloy fin 201 (thermal conductivity 180 W / (m·K)), and its maximum temperature drop at the interface is only 0.04℃, almost completely eliminating the heat sink effect; Example 1 uses 316L stainless steel fin 201 (thermal conductivity 22 W / (m·K)), and the maximum temperature drop at the interface is 0.22℃, which is also within an acceptable range. As a counter-reference, the applicant previously tested a scheme in which the heat-conducting fin 201 was replaced with alumina ceramic (thermal conductivity approximately 1.2 W / (m·K)) – with the same heat exchange area (2100 cm²). 2 Under these conditions, the interface temperature drop increases sharply to 12.4℃, and the saturation drops to 70.5%. This set of comparative data clearly reveals the indispensable synergistic relationship between "liquid film extension component 1 providing the area basis" and "thermal conductive component 2 providing thermal compensation guarantee"—without efficient thermal compensation, the overall gasification performance of the system will be severely restricted by the heat sink effect if there is only a large mass exchange area.

[0089] (3) Complete superiority over the bubbling method. Although the vapor saturation (79.0%) of Comparative Example 2 (bubbling cylinder) is better than that of static purging (44.3%), it is far inferior to any embodiment of the present invention. More importantly, the bubbling method produces a droplet entrainment rate as high as 4.21%, which is incomparable to the near-zero entrainment rate of the embodiments of the present invention. In addition, the total pressure drop of the gas path system of the bubbling method is as high as about 280 Pa (mainly from the flow resistance of the submerged tube and the static pressure of the liquid column), which is about 3 times that of the present invention, and has an adverse effect on the control accuracy of the upstream mass flow controller.

[0090] (4) Excellent low residual liquid characteristics. The residual liquid rates of Comparative Examples 1 and 2 were as high as 6.5% and 3.2% or more, respectively, while the residual liquid rates of all embodiments of the present invention were below 0.6%, and further decreased with the increase of the 10-level extension member (the residual liquid rate of Example 3 with the five-level configuration was only below 0.2%). The low residual liquid rate has extremely significant economic value for expensive precursors with a price of thousands to tens of thousands of US dollars per liter.

[0091] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0092] The preferred embodiments of the invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A liquid level expansion system, characterized in that, Displaced within the cavity of a container for containing a liquid precursor, comprising: A liquid film spreading assembly includes at least two spreading members stacked vertically at intervals. The liquid film spreading assembly is configured to receive a liquid precursor introduced from above during the filling stage and to guide the liquid precursor downwards along the spreading surfaces of each spreading member by gravity, such that a thin liquid film remains on each spreading surface after filling. A heat-conducting component is disposed between the inner wall of the container and the liquid film extension assembly to establish a heat conduction path from the outside of the container to the extension assembly, so as to conduct external heat to the liquid film.

2. The liquid level expansion system according to claim 1, characterized in that, The liquid film stretching assembly includes: At least one first extension member having a through opening in a central region and a first extension surface surrounding the through opening, the liquid precursor being adapted to flow along the first extension surface toward the through opening and overflow downward through the through opening during filling; At least one second extension member having a closed central region, at least one overflow notch located on the outer periphery, and a second extension surface surrounding the central region, the liquid precursor being adapted to flow along the second extension surface from the central region toward the overflow notch and overflow downward through the overflow notch during filling; The first extension member and the second extension member are arranged alternately in the vertical direction, so that the radial flow direction of the liquid precursor on the two adjacent extension members is opposite.

3. The liquid level expansion system according to claim 2, characterized in that, A liquid film flattening structure is provided on the first extended surface and / or the second extended surface. The liquid film flattening structure is configured to apply a flattening force to the liquid precursor in a direction intersecting the radial flow direction to maintain the thickness of the liquid film within a preset range.

4. The liquid level expansion system according to claim 3, characterized in that, The liquid film flattening structure includes at least one groove processed along the extended surface, which flattens and spreads the liquid in a direction transverse to the radial flow direction through the synergistic effect of capillary action and liquid surface tension.

5. The liquid level expansion system according to claim 1, characterized in that, It also includes an auxiliary gas-liquid contact component disposed below the liquid film extension component. The auxiliary gas-liquid contact component has a three-dimensional porous structure and is configured to attach and extend residual liquid falling from above through capillary action to form an extended microliquid film.

6. The liquid level expansion system according to claim 5, characterized in that, The auxiliary gas-liquid contact component is a multi-layer structure composed of at least two overlapping porous sheets, wherein the porosity of each layer in the multi-layer structure is different.

7. The liquid level expansion system according to claim 5, characterized in that, The heat-conducting component includes at least three ribs spaced apart circumferentially, each rib having a radially outer end that fits against the inner wall of the container and a radially inner end that connects to the liquid film extension assembly.

8. A precursor gasification and conveying device, characterized in that, It is disposed in the inner cavity of a container for containing a liquid precursor, including: The liquid level expansion system as described in any one of claims 1-7.

9. The precursor gasification and conveying device according to claim 8, characterized in that, Also includes: A swirling air inlet component, installed at the air inlet of the container, is used to convert the introduced carrier gas into a circumferential rotating jet, so that the carrier gas flows sequentially through the liquid film on each stage of the extended surface and the extended micro-liquid film on the auxiliary gas-liquid contact component in a tangential sweeping manner.

10. The precursor gasification and conveying device according to claim 9, characterized in that, The swirl intake component has at least one outlet channel that is inclined at an angle to the vertical axis, the inclination angle being 15° to 60°.

11. A semiconductor precursor cylinder, characterized in that, include: The bottle body has an internal cavity for containing the liquid precursor; The liquid level expansion system as described in any one of claims 1-7 is installed inside the cavity; as well as A heating device is disposed outside the bottle body for heating the bottle body, and the heat generated by the heating device is at least partially conducted to the liquid film via the heat-conducting member.

12. A method for vaporizing and transporting a liquid precursor, characterized in that, The method, applied to the inner cavity of a container, includes the following steps: Filling stage: The liquid precursor is introduced from the upper region of the inner cavity and spreads downwards step by step along at least two vertically spaced extended surfaces under gravity, so that a thin liquid film is retained on each of the extended surfaces after filling. Vaporization operation stage: Through the heat conduction path thermally coupled between the inner wall of the container and the extended surface, heat conducted from the outside of the container is supplied to the liquid film on each of the extended surfaces to compensate for the heat required for the vaporization of the liquid on the liquid film. The carrier gas is introduced into the inner cavity in the form of a circumferential rotating jet, and flows sequentially through the liquid film on each stage of the extended surface in a tangential sweeping manner, so as to carry the vaporized precursor vapor out of the outlet of the inner cavity.

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