Fluid delivery drip prevention system, method and use thereof in semiconductor manufacturing

Abstract

The application discloses a fluid delivery anti-dripping system, a method and application thereof in semiconductor manufacturing. The system comprises: a valve body with a fluid channel; a fluid cutting device; a viscosity temporary reduction device for applying energy to the fluid before cutting to temporarily reduce the viscosity; a volume expansion actuating assembly comprising a movable displacement member and a variable volume cavity surrounded thereby; and a fast response driving device for driving the displacement member to retract after cutting to increase the volume of the variable volume cavity and generate negative pressure, thereby sucking the fluid at the fluid outlet back to the inside of the valve body. The application actively reduces the viscosity before cutting and quickly generates negative pressure to suck back after cutting, which are physically coordinated to completely eliminate the problems of high viscosity fluid nozzle stringing, carbon deposition and thermal decomposition blockage, thereby ensuring high steepness of ALD gas phase pulse and long-term zero carbonization operation of the pipeline.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor integrated circuit manufacturing equipment technology, and specifically relates to a fluid delivery anti-drip system, method and its application in semiconductor manufacturing. Background Technology

[0002] In advanced semiconductor manufacturing processes, such as high-k metal gate processes and 3D NAND charge trapping layer deposition, atomic layer deposition (ALD) technology is widely used in the fabrication of ultrathin, uniform dielectric films in ultra-high aspect ratio nanostructures. With the continuous introduction of new materials, the application of medium-to-high viscosity precursors (with room temperature viscosity between 8 cP and 20 cP), represented by hafnium (Hf) and niobium (Nb) sources, is increasing.

[0003] However, due to the strong intermolecular attraction of these high-viscosity precursors, when mechanically cut off at the end of the delivery pipeline, residual droplets easily form at the outlet of the shut-off valve due to the high viscosity and surface tension, resulting in stringing and dripping. This residual precursor, exposed to the high-temperature pre-pipeline environment of the vaporizer or ampoule, undergoes rapid localized thermal decomposition, producing high-hardness metal oxides and carbon deposits, leading to localized carbon buildup and blockage in the pipeline and precision vaporization nozzles (e.g., Figure 6 As shown in the figure, it severely disrupts the steep boundary of the ALD vapor phase pulse, induces unexpected chemical vapor deposition (CVD) side reactions, and then introduces catastrophic intra-sheet particle defects and reduces film uniformity.

[0004] Currently, traditional anti-drip methods mainly rely on nozzle geometry optimization or simple mechanical pull-back. However, for high-viscosity fluids of 8cP to 20cP, due to the large internal frictional resistance and lag response, conventional mechanical pull-back cannot generate sufficient local negative pressure in a very short time to overcome the cohesive force of high-viscosity fluids, and stringing remains a serious problem. Therefore, how to rapidly reduce fluid viscosity at the moment of cutting and actively provide strong negative pressure backflow to eliminate nozzle residue has become a major technical bottleneck in the hardware design of ALD equipment. Summary of the Invention

[0005] In view of the problems in related technologies, the present invention proposes a fluid delivery anti-drip system and method and its application in semiconductor manufacturing, so as to overcome the above-mentioned technical problems existing in the existing related technologies.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: A fluid delivery anti-drip system, comprising: The valve body has an internal fluid passage with a fluid inlet and a fluid outlet. A fluid shut-off device, located within the valve body, is used to control the opening and closing of the fluid channel; A viscosity reduction device is configured to apply energy to the fluid in the fluid channel before the fluid cut-off device cuts off the fluid channel, so as to temporarily reduce the viscosity of the fluid; The volume expansion actuation assembly includes a displacement member movably disposed in the valve body and communicating with the fluid passage, the displacement member forming a variable volume cavity between the fluid cut-off device and the fluid outlet; A fast-response drive device, connected to the displacement member, is configured to drive the displacement member to retract within a preset time after the fluid cut-off device cuts off the fluid channel, thereby increasing the volume of the variable volume cavity, generating negative pressure in the variable volume cavity, and drawing the fluid at the fluid outlet back into the valve body.

[0007] In some embodiments, the viscosity reduction device is an ultrasonic transducer used to apply high-frequency ultrasonic energy to the fluid to perform acoustic shear thinning. The ultrasonic transducer is an external clamp-on type, tightly fitted onto the outer wall of the fluid inlet of the valve body, to apply ultrasonic energy to the fluid in the fluid channel in a non-invasive manner.

[0008] In some embodiments, the fluid cut-off device is a main shut-off diaphragm disposed within the valve body.

[0009] In some embodiments, the displacement element is a displacement compensation plunger, with a dynamic seal penetrating the valve body. The end of the displacement compensation plunger extends into the fluid channel and forms a local expansion negative pressure chamber below the main shut-off diaphragm. The variable volume chamber is adjusted by the retraction of the displacement compensation plunger.

[0010] In some embodiments, the fast-response drive device is a piezoelectric stacked driver, located outside the valve body, for driving the displacement element to perform microsecond-level axial pull-back displacement.

[0011] In some embodiments, the system further includes a controller electrically connected to the viscosity sag device, the drive mechanism of the fluid cut-off device, and the fast-response drive device, respectively, for performing the following coordinated control timing during the shutdown phase: in a first phase, controlling the viscosity sag device to apply energy to the fluid, causing the viscosity of the fluid to decrease to below a preset threshold; in a second phase, after the viscosity of the fluid decreases to below the preset threshold, controlling the fluid cut-off device to cut off the fluid channel; in a third phase, after the fluid channel is cut off, controlling the fast-response drive device to drive the displacement member to retract, thereby increasing the volume of the variable volume cavity and generating negative pressure to draw back the fluid at the fluid outlet.

[0012] In some embodiments, the viscosity sag device is an ultrasonic transducer with an emission frequency of 20kHz to 50kHz and an emission power of 100W to 300W; the fast response drive device (50) is a piezoelectric stacked driver with a response time of 100μs to 300μs in the third stage and a negative retraction displacement of 0.2mm to 0.6mm for driving the displacement member (40).

[0013] In some embodiments, the fluid channel, the fluid cut-off device, and the liquid-contacting surfaces of the displacement element are all made of ultra-high purity stainless steel with a surface roughness Ra ≤ 0.1 μm. The viscosity of the fluid at room temperature is 8 cP to 20 cP, and after being processed by the viscosity reduction device, the viscosity is reduced to below 3 cP. The fluid outlet is connected to the pre-inlet of a downstream container via a process pipeline, and the downstream container is a liquid vaporizer or a secondary storage container.

[0014] In some embodiments, the fluid is a hafnium source precursor TEMAH, with an initial viscosity of 9.5 cP at 45°C; the viscosity reduction device is an externally clamped ultrasonic transducer with an operating frequency of 40 kHz and a power of 180 W, which acoustically shears-thins the viscosity of the TEMAH to 2.1 cP; the fast-response driving device is a piezoelectric stacked actuator with an axial pull-back response time of 180 μs, driving the retraction displacement of the displacement element to 0.32 mm, generating a local negative pressure of -12.4 kPa in the variable volume cavity, and drawing the TEMAH at the fluid outlet back into the valve body by 3.8 mm.

[0015] In some embodiments, the fluid is a niobium source precursor with an initial viscosity of 18.5 cP at 25°C; the viscosity sag device is an externally clamped ultrasonic transducer with an operating frequency of 28 kHz and a power of 260 W, which acoustically shears-thins the viscosity of the niobium source precursor to 2.8 cP; the fast-response driving device is a piezoelectric stacked actuator with an axial pull-back response time of 220 μs, which drives the retraction displacement of the displacement element to 0.45 mm, generating a local negative pressure of -18.5 kPa in the variable volume cavity, and drawing the niobium source precursor at the fluid outlet back into the valve body by 4.5 mm.

[0016] This invention also proposes a method for preventing dripping during fluid transport, applied to the aforementioned system, comprising the following steps: With the fluid channel open and fluid being transported, energy is applied to the fluid to temporarily reduce the viscosity of the fluid to a preset threshold. After the viscosity of the fluid decreases to the preset threshold, the fluid cut-off device is controlled to cut off the fluid channel; Within a preset time after the fluid channel is cut off, the control fast response drive device drives the displacement component to retract, thereby increasing the volume of the variable volume cavity connected to the fluid channel. A negative pressure is generated in the variable volume cavity, drawing the fluid at the fluid outlet back into the valve body.

[0017] In some embodiments, applying energy to the fluid includes: applying high-frequency ultrasonic energy of 20kHz to 50kHz and 100W to 300W to the fluid via an externally clamped ultrasonic transducer to perform acoustic shear thinning of the fluid.

[0018] In some embodiments, the control of the fast-response drive device to drive the displacement member to retract includes: controlling the piezoelectric stack driver to drive the displacement compensation plunger to generate a negative axial retraction displacement of 0.2 mm to 0.6 mm within 100 μs to 300 μs, generating a local negative pressure of -5 kPa to -20 kPa in the local expansion negative pressure chamber, and drawing the fluid at the fluid outlet back into the valve body by 2 mm to 5 mm.

[0019] This invention also proposes the application of the above-mentioned fluid transport anti-drip system in semiconductor manufacturing, particularly for the transport, cutting and anti-drip of liquid precursors in atomic layer deposition processes.

[0020] Compared with the prior art, the present invention has the following beneficial effects: (1) By setting up a viscosity reduction device, the viscosity of the fluid is actively reduced before the fluid is cut off, thereby physically releasing the entanglement and stringing force of high-viscosity fluid macromolecules and providing a fluid environment with extremely low resistance for subsequent negative pressure back suction. Compared with existing solutions that rely solely on mechanical structure optimization or passive back pull, this invention fundamentally solves the residue problem caused by high-viscosity fluid stringing.

[0021] (2) Through the coordination of the volume expansion actuation component and the fast response drive device, the volume of the variable volume cavity is actively increased in a very short time after the fluid channel is cut off, generating a strong local negative pressure, overcoming the viscous resistance and surface tension of the residual fluid at the end, drawing the fluid back from the outlet nozzle to the inside of the valve body, and forming a self-locking concave crescent liquid surface on the inner wall of the nozzle, thus completely eliminating the nozzle stringing and dripping phenomena.

[0022] (3) Since the liquid surface is completely retreated into the safe cold zone after back suction, the precursor liquid surface is physically isolated from the high-temperature front pipeline and high-temperature nozzle, which fundamentally eliminates the thermal decomposition reaction of the precursor, realizes the long-term zero carbon deposition operation of the pipeline, and ensures the high steepness of ALD gas phase pulse and film uniformity.

[0023] (4) The viscosity descent device can be installed in a non-contact manner (such as an external clamp ultrasonic transducer) without intruding into the fluid channel and is compatible with the cleanliness requirements of semiconductor ultrapure fluid transportation; the displacement component adopts a dynamic sealing through structure to ensure the system's airtightness. Attached Figure Description

[0024] 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.

[0025] Figure 1 This is a schematic diagram of the structure of a fluid delivery anti-drip system according to the present invention; Figure 2 for Figure 1 Enlarged schematic diagram of the middle Q section; the system is not in a closed state at this time. Figure 3 for Figure 1 Enlarged schematic diagram of the middle Q section; the system is currently in the off state. Figure 4 This is a control timing waveform diagram of a fluid delivery anti-drip system according to the present invention; Figure 5 This is a schematic diagram of the active back-suction anti-drip effect at the outlet of a fluid transport anti-drip system of the present invention after it is closed; Figure 6This is a schematic diagram of the structure of localized carbon buildup and clogging in nozzles in the background art.

[0026] Among them: 100-valve body, 200-fluid shut-off device, 300-viscosity descent device, 400-volume expansion actuation component, 500-fast response drive device, 600-controller, 101-fluid channel, 102-fluid inlet, 103-fluid outlet, 410-displacement component, 420-local expansion negative pressure chamber. Detailed Implementation

[0027] 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.

[0028] 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.

[0029] Reference Figures 1-5 As shown, a fluid delivery anti-drip system includes: a valve body 100, a fluid shut-off device 200, a viscosity descent device 300, a volume expansion actuation component 400, a fast response drive device 500, and a controller 600.

[0030] The valve body 100 of the present invention has a fluid channel 101 inside, the fluid channel 101 has a fluid inlet 102 and a fluid outlet 103; a fluid cut-off device 200 is disposed inside the valve body 100 for controlling the opening and closing of the fluid channel 101; wherein, the fluid cut-off device 200 is a main shut-off diaphragm disposed inside the valve body 100.

[0031] The viscosity sag device 300 of the present invention is configured to apply energy to the fluid in the fluid channel 101 before the fluid cut-off device 200 cuts off the fluid channel 101, so as to temporarily reduce the viscosity of the fluid. Generally, the viscosity sag device 300 is an ultrasonic transducer used to apply high-frequency ultrasonic energy to the fluid to perform acoustic shear thinning of the fluid. The ultrasonic transducer is an external clamp-on ultrasonic transducer, tightly fitted to the outer wall of the fluid inlet 102 of the valve body 100, to apply ultrasonic energy to the fluid in the fluid channel 101 in a non-invasive manner.

[0032] Generally, high-viscosity precursors (such as liquids with a viscosity of 8-20 cP) have high viscosity at room or intermediate temperatures primarily due to the complex physical association networks between their molecules (such as van der Waals forces, dipole-dipole interactions, or long-chain physical entanglement of metal-organic molecular chains). Under the action of an ultrasonic transducer, when high-energy ultrasound waves are injected into the pipe, an extremely high-frequency shear stress field is generated inside the liquid. The molecular chains of the high-viscosity precursor rapidly orient themselves along the flow direction, and the physical entanglement between molecules is instantaneously "straightened" and "untied," resulting in a sharp drop in molecular sliding resistance, macroscopically manifested as an instantaneous decrease in viscosity. When the ultrasonic transducer is turned off, the shear field disappears, and the molecules, under thermal motion, will re-entangle randomly within a very short time, instantly restoring the viscosity to its original state. This invention reduces the viscosity of fluids through physical means without causing chemical changes in the fluid.

[0033] The volume expansion actuation assembly 400 of the present invention includes a displacement member 410 movably disposed in the valve body 100 and communicating with the fluid channel 101. The displacement member 410 surrounds the fluid cut-off device 200 and the fluid outlet 103 to form a local expansion negative pressure chamber 420. The displacement member 410 is a displacement compensation plunger, dynamically sealed through the valve body 100. The end of the displacement compensation plunger extends into the fluid channel 101 and surrounds the local expansion negative pressure chamber 420 below the main cut-off diaphragm. The variable volume chamber 430 is adjusted by the retraction of the displacement compensation plunger. The volume expansion actuation assembly 400 in the present invention can be one or more to adapt to fluids of different viscosities or valve bodies 100 of different diameters. Generally, when the fluid viscosity is too high or the diameter of the valve body 100 is large, multiple volume expansion actuation assemblies 400 are required or the movable stroke of the displacement member 410 is increased. In this embodiment, there is one volume expansion actuation assembly 400.

[0034] The fast-response drive device 500 of the present invention is driven to connect with the displacement member 410. It is configured to drive the displacement member 410 to retract within a preset time after the fluid cut-off device 200 cuts off the fluid channel 101, thereby forming a variable volume cavity 430. This generates a negative pressure within the variable volume cavity 430, drawing the fluid from the fluid outlet 103 back into the valve body 100. The fast-response drive device 500 is a piezoelectric stacked actuator, located outside the valve body 100, and is used to drive the displacement member 410 to perform microsecond-level axial pull-back displacement.

[0035] The controller 600 of the present invention is electrically connected to the viscosity sag device 300, the drive mechanism (not shown in the figure) of the fluid cut-off device 200, and the fast response drive device 500, respectively, and is used to perform the following coordinated control timing during the shutdown phase: In the first phase, the viscosity sag device 300 is controlled to apply energy to the fluid, so that the viscosity of the fluid is reduced to below a preset threshold; in the second phase, after the viscosity of the fluid is reduced to below the preset threshold, the fluid cut-off device 200 is controlled to cut off the fluid channel 101; in the third phase, after the fluid channel 101 is cut off, the fast response drive device 500 is controlled to drive the displacement member 410 to retract, so as to increase the volume of the variable volume cavity and generate negative pressure, and draw back the fluid at the fluid outlet 103.

[0036] The viscosity sag device 300 of the present invention is an ultrasonic transducer with a transmission frequency of 20kHz to 50kHz and a transmission power of 100W to 300W; the fast response drive device 500 is a piezoelectric stacked driver with a response time of 100μs to 300μs in the third stage and a negative retraction displacement of 0.2mm to 0.6mm for the drive displacement member 410.

[0037] The fluid channel, the fluid cut-off device, and the liquid-contacting surfaces of the displacement element in this invention are all made of ultra-high purity stainless steel, with a surface roughness Ra ≤ 0.1 μm. The viscosity of the fluid at room temperature is 8 cP to 20 cP, and after being processed by the viscosity reduction device, the viscosity is reduced to below 3 cP. The fluid outlet is connected to the pre-inlet of a downstream container via a process pipeline, and the downstream container is a liquid vaporizer or a secondary storage container.

[0038] This invention also proposes a method for preventing dripping during fluid transport, applied to the aforementioned system, comprising the following steps: With the fluid channel open and fluid being transported, energy is applied to the fluid to temporarily reduce the viscosity of the fluid to a preset threshold. After the viscosity of the fluid decreases to the preset threshold, the fluid cut-off device is controlled to cut off the fluid channel; Within a preset time after the fluid channel is cut off, the control fast response drive device drives the displacement component to retract, thereby increasing the volume of the variable volume cavity connected to the fluid channel. A negative pressure is generated in the variable volume cavity, drawing the fluid at the fluid outlet back into the valve body.

[0039] The present invention will now be described with reference to specific embodiments.

[0040] Example 1 (Hafnium source precursor TEMAH): The liquid precursor used in this embodiment is a high-viscosity hafnium source, TEMAH, with a room temperature viscosity of 9.5 cP (actual viscosity at 45°C). In this embodiment, the fluid cut-off device specifically employs a main shut-off diaphragm; the viscosity sag device specifically employs an externally clamped ultrasonic transducer; the displacement element specifically employs a displacement-compensating plunger, whose end surrounds the main shut-off diaphragm to form a localized expansion negative pressure cavity; simultaneously, the displacement-compensating plunger retracts to form a variable volume cavity; the fast-response drive device specifically employs a piezoelectric stacked actuator. The fluid outlet is connected to the pre-stage inlet of the ALD equipment's vaporizer via a 316LEP ultra-high purity stainless steel process pipe, which is located in a high-temperature radiation environment at 150°C.

[0041] During the drug delivery period (T0), the externally clamped ultrasonic transducer maintains operation with a low-frequency pulse of 30W power, without interfering with normal fluid delivery.

[0042] During the cutoff preparation period (T1), the controller controls the external clamp ultrasonic transducer to instantly increase the transmission power to 180W (operating frequency 40kHz).

[0043] According to the modified Cross-rheological model: ; in: η0 is the initial static viscosity of the precursor fluid (8 cP to 20 cP at room temperature and pressure). η ∞ This is the limiting shear-thinning viscosity (i.e., the limiting viscosity in the state of complete disentanglement of molecular chains, approximately 1.5 cP to 2 cP). λ is the relaxation time constant of the fluid; m is the exponential coefficient for non-Newtonian fluids; The equivalent high-frequency shear thinning rate introduced into the ultrasonic sound field is exponentially positively correlated with the sound intensity I: ; Here, f is the ultrasonic operating frequency (20kHz-50kHz), and k and α are the fluid acoustic shear coupling coefficients.

[0044] When the ultrasonic power is instantly maximized, causing a sharp increase in acoustic intensity I, the equivalent shear rate rises exponentially, instantly acoustically shearing-thinning the flow viscosity of the hafnium source precursor TEMAH to 2.1 cP. This instantly dissolves the physical entanglement and fiber-pulling forces of the high-viscosity macromolecules, providing an extremely low-resistance fluid physics environment for subsequent reabsorption. The main shut-off diaphragm then closes rapidly.

[0045] During the back-suction lock-up period (T2), the piezoelectric stack actuator applies a negative voltage within 180 μs to drive the displacement compensation plunger, resulting in a 0.32 mm backward negative displacement. Due to the sudden drop in viscosity to 2.1 cP, the motion resistance term is significantly reduced. The rapid axial retraction of the plunger causes an instantaneous increase in the physical volume of the local expansion negative pressure chamber. Based on fluid compressibility and the transient Navier-Stokes equations, under the combined effect of ultrasonic shear thinning reducing viscosity by an order of magnitude and the extremely short response time of the piezoelectric stack resulting in a large acceleration term, a sudden local negative pressure of up to -12.4 kPa is instantaneously generated within the local chamber. According to kinetic calculations, the TEMAH at the fluid outlet nozzle is rapidly and cleanly pulled inward by 3.8 mm, forming a perfectly concave crescent-shaped liquid surface inside the nozzle.

[0046] After the back suction is completed, the concave crescent-shaped liquid surface stabilizes on the ultra-smooth inner wall (Ra≤0.1μm). Based on the Laplace capillary force balance condition, and with the high contact angle stability maintained by the ultra-smooth inner wall and the active back suction depth of 3.8mm, the precursor liquid surface is completely retreated into the safe cold zone protected by the temperature control circuit, completely eliminating thermal radiation contact with the high-temperature vaporization pre-pipeline and high-temperature nozzle.

[0047] After 50,000 ALD deposition pulse tests, no hafnium dioxide or thermal decomposition carbon deposits were found inside the connecting pipe and the vaporizer nozzle, and the increase in film particle size was 0.

[0048] Example 2 (Ultra-high viscosity niobium source precursor pentaethanol niobium / niobium pentafluoride mixed fluid): This embodiment uses an ultra-high viscosity niobium (Nb) source precursor, with a static initial viscosity as high as 18.5 cP at 25°C. The fluid outlet points to the high-temperature heating precursor pre-stage of the secondary storage container (Ampoule). The specific selection of each component in this embodiment is the same as in Embodiment 1.

[0049] During the cutoff preparation period (T1), the clamp-on ultrasonic transducer continuously performs strong acoustic shearing at a powerful 28kHz vibration frequency and a high energy power of 260W. The ultrasonic cavitation effect instantly breaks the association network of the niobium source macromolecules, causing its equivalent shear thinning rate to increase by several orders of magnitude, and the viscosity to drop sharply to 2.8cP. Subsequently, the main valve is completely shut off.

[0050] During the back-suction lock-up period, the piezoelectric stack actuator rapidly drives the displacement compensation plunger to generate a retraction displacement of -0.45mm within 220μs, successfully generating a high-intensity local expansion vacuum negative pressure of -18.5kPa. In a very short time, it overcomes the physical residual traction force of the high-viscosity liquid and forcibly draws the niobium source liquid neatly back to a depth of 4.5mm, forming a concave semi-lunar lock-up.

[0051] After 30,000 extreme deposition cycles, no thermal decomposition or local blockage of niobium precursors occurred in the high-temperature pipeline.

[0052] Compared with the prior art, the present invention has the following beneficial effects: (1) By setting up a viscosity reduction device, the viscosity of the fluid is actively reduced before the fluid is cut off, thereby physically releasing the entanglement and stringing force of high-viscosity fluid macromolecules and providing a fluid environment with extremely low resistance for subsequent negative pressure back suction. Compared with existing solutions that rely solely on mechanical structure optimization or passive back pull, this invention fundamentally solves the residue problem caused by high-viscosity fluid stringing.

[0053] (2) Through the coordination of the volume expansion actuation component and the fast response drive device, the volume of the variable volume cavity is actively increased in a very short time after the fluid channel is cut off, generating a strong local negative pressure, overcoming the viscous resistance and surface tension of the residual fluid at the end, drawing the fluid back from the outlet nozzle to the inside of the valve body, and forming a self-locking concave crescent liquid surface on the inner wall of the nozzle, thus completely eliminating the nozzle stringing and dripping phenomena.

[0054] (3) Since the liquid surface is completely retreated into the safe cold zone after back suction, the precursor liquid surface is physically isolated from the high-temperature front pipeline and high-temperature nozzle, which fundamentally eliminates the thermal decomposition reaction of the precursor, realizes the long-term zero carbon deposition operation of the pipeline, and ensures the high steepness of ALD gas phase pulse and film uniformity.

[0055] (4) The viscosity descent device can be installed in a non-contact manner (such as an external clamp ultrasonic transducer) without intruding into the fluid channel and is compatible with the cleanliness requirements of semiconductor ultrapure fluid transportation; the displacement component adopts a dynamic sealing through structure to ensure the system's airtightness.

[0056] 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.

[0057] 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 fluid delivery anti-drip system, characterized in that, include: The valve body has an internal fluid passage with a fluid inlet and a fluid outlet. A fluid shut-off device, located within the valve body, is used to control the opening and closing of the fluid channel; A viscosity reduction device is configured to apply energy to the fluid in the fluid channel before the fluid cut-off device cuts off the fluid channel, so as to temporarily reduce the viscosity of the fluid; The volume expansion actuation assembly includes a displacement member movably disposed in the valve body and communicating with the fluid passage, the displacement member forming a variable volume cavity between the fluid cut-off device and the fluid outlet; A fast-response drive device, connected to the displacement member, is configured to drive the displacement member to retract within a preset time after the fluid cut-off device cuts off the fluid channel, thereby increasing the volume of the variable volume cavity, generating negative pressure in the variable volume cavity, and drawing the fluid at the fluid outlet back into the valve body.

2. The fluid delivery anti-drip system according to claim 1, characterized in that, The viscosity descent device is an ultrasonic transducer used to apply high-frequency ultrasonic energy to the fluid to perform acoustic shear thinning.

3. The fluid delivery anti-drip system according to claim 1, characterized in that, The displacement element is a displacement compensation plunger, with a dynamic seal penetrating the valve body. The end of the displacement compensation plunger extends into the fluid channel and forms a local expansion negative pressure chamber. The variable volume chamber is adjusted by the retraction of the displacement compensation plunger.

4. The fluid delivery anti-drip system according to claim 1, characterized in that, The fast-response drive device is a piezoelectric stacked actuator, located outside the valve body, used to drive the displacement component to perform microsecond-level axial pull-back displacement.

5. The fluid delivery anti-drip system according to claim 1, characterized in that, The system also includes a controller, which is electrically connected to the viscosity descent device, the drive mechanism of the fluid cutoff device, and the fast response drive device, respectively, for executing the following coordinated control timing during the shutdown phase: In the first stage, the viscosity descent device is controlled to apply energy to the fluid, causing the viscosity of the fluid to decrease to below a preset threshold. In the second stage, after the viscosity of the fluid decreases to below the preset threshold, the fluid cut-off device is controlled to cut off the fluid channel. In the third stage, after the fluid channel is cut off, the fast-response drive device is controlled to drive the displacement member to retract, thereby increasing the volume of the variable volume cavity and generating negative pressure to draw back the fluid at the fluid outlet.

6. The fluid delivery anti-drip system according to claim 5, characterized in that, The viscosity sag device is an ultrasonic transducer with a transmission frequency of 20kHz to 50kHz and a transmission power of 100W to 300W; the fast response drive device is a piezoelectric stacked actuator with a response time of 100μs to 300μs in the third stage and a negative retraction displacement of 0.2mm to 0.6mm for driving the displacement element.

7. The fluid delivery anti-drip system according to claim 5, characterized in that, The fluid channel, the fluid cut-off device, and the liquid-contacting surfaces of the displacement component are all made of ultra-high purity stainless steel, and the surface roughness Ra≤0.1μm.

8. The fluid delivery anti-drip system according to claim 5, characterized in that, The viscosity of the fluid at room temperature is 8 cP to 20 cP, and after being processed by the viscosity derating device, the viscosity is reduced to below 3 cP.

9. A method for preventing dripping during fluid transport, applied to the system according to any one of claims 1 to 8, characterized in that, Includes the following steps: With the fluid channel open and fluid being transported, energy is applied to the fluid to temporarily reduce the viscosity of the fluid to a preset threshold. After the viscosity of the fluid decreases to the preset threshold, the fluid cut-off device is controlled to cut off the fluid channel; Within a preset time after the fluid channel is cut off, the control fast response drive device drives the displacement component to retract, thereby increasing the volume of the variable volume cavity connected to the fluid channel. A negative pressure is generated in the variable volume cavity, drawing the fluid at the fluid outlet back into the valve body.

10. An application of the fluid delivery anti-drip system as described in any one of claims 1 to 8 in semiconductor manufacturing, characterized in that, The system is used for the delivery, cutting, and drip prevention of liquid precursors in atomic layer deposition processes.

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