ALD precursor storage device
By using a telescopic elastic device and a piston device in the ALD precursor storage device, the problem of insufficient saturated vapor pressure of reactant gas is solved, the film uniformity and conveying efficiency are improved, and the WAT failure and the impact of integrated circuit performance is avoided.
Patent Information
- Application Number
- CN202421660775.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-12
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-07-12
AI Technical Summary
In the existing ALD technology, insufficient saturated vapor pressure of the reactant gas leads to low efficiency of the reactant gas, thin film formation on the substrate and poor uniformity, affecting the performance of WAT and integrated circuits.
ALD precursor storage device including a retractable elastic device and a piston device is adopted to adjust the pressure balance in the container through the elastic mechanism to ensure that the reactant gas always maintains saturated vapor pressure.
It improves the efficiency of reactant gas, ensures uniformity of the film on the substrate, and reduces the impact of WAT failure and integrated circuit performance.
Smart Images
Figure CN222795720U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of atomic layer deposition, in particular to an ALD precursor storage device. Background Art
[0002] With the continuous development of the semiconductor industry, the size of devices is becoming smaller and smaller, making it particularly important to find or develop more advanced thin film growth technologies. These devices require low thermal budget, high film thickness accuracy and excellent conformality in three-dimensional (3D) structures. However, traditional deposition technologies, chemical vapor deposition (CVD) and physical vapor deposition (PVD) can no longer fully adapt to this development trend. Atomic layer deposition (ALD) technology has a wide range of application potentials in fields such as microelectronics and nanomaterials due to its high controllability of deposition parameters (thickness, composition and structure), excellent uniformity and conformality.
[0003] During the deposition process of ALD, the reactant gases are deposited alternately, and the chemical reaction of a new layer of atomic film is directly related to the previous layer, and only one layer of atoms is deposited each time. It has the characteristics of self-limited growth, which allows the film to be deposited conformally and pinhole-free on the substrate, so the film thickness can be precisely controlled by controlling the number of deposition cycles. Based on the process principle of ALD technology, it is necessary to carry out under the condition of saturated vapor pressure to ensure the transport efficiency of the reactant gas from the container to the reaction chamber and the uniformity of the ALD film deposition process. In the process of depositing thin films using ALD technology, in order to maintain the state of saturated vapor pressure of the reactant gas in the container body, the prior art generally only adopts the method of surrounding the outer wall of the container body storing the ALD precursor with a heating belt, continuously heating the reactant solid, and maintaining or adjusting the temperature of the reactant gas in the container to ensure that the reactant gas is carried out by the inert gas under the state of saturated vapor pressure and reacts on the substrate.
[0004] As the ALD deposition process continues, the pressure gauge on the top of the container body cannot promptly feedback the actual pressure in the container, and the heating belt has limited effect on maintaining the saturated vapor pressure, resulting in a rate at which the reactant solid in the container body is converted into reactant gas that is lower than the rate at which the reactant gas is consumed during ALD film deposition. The vapor pressure of the reactant gas decreases, and the saturated vapor pressure of the reactant gas is insufficient, which reduces the efficiency of transporting the reactant gas from the container body to the reaction chamber. As a result, the film formed on the substrate within the same ALD deposition time is thin and the film uniformity is poor, which leads to failure of the wafer acceptance test (WAT), which may ultimately affect the performance of the integrated circuit. Utility Model Content
[0005] In view of the shortcomings of the prior art described above, the purpose of the utility model is to provide an ALD precursor storage device for solving the problem in the prior art that the saturated vapor pressure of the reactant gas is insufficient during the ALD continuous reaction, resulting in low efficiency in transporting the reactant gas from the container body to the reaction chamber, resulting in a thin film formed on the substrate within the same ALD deposition time, poor film uniformity, and thus causing WAT failure, ultimately affecting the performance of the integrated circuit.
[0006] In order to achieve the above-mentioned object and other related objects, the utility model provides an ALD precursor storage device, the storage device comprising: a container body and an elastic mechanism;
[0007] The elastic mechanism is arranged at the lower part of the interior of the container body;
[0008] The elastic mechanism includes a retractable elastic device and a piston device; one end of the retractable elastic device is fixed to the inner bottom of the container body, and the other end is connected to the piston device; the piston device divides the internal space of the container body into a first space and a second space along the up and down directions, and makes the second space a sealed space, the retractable elastic device is accommodated in the second space, and the precursor is accommodated in the first space; the piston device can move up and down inside the container body with the extension and compression of the retractable elastic device, so that the pressure on both sides of the piston device is balanced.
[0009] Optionally, the container body is a steel cylinder.
[0010] Optionally, the retractable elastic device is a spring.
[0011] Optionally, the outer side wall of the container body is surrounded by a heating belt.
[0012] Optionally, the elastic mechanism includes more than two retractable elastic devices, and all the retractable elastic devices are evenly accommodated in the second space.
[0013] Furthermore, one end of the retractable elastic device is fixedly connected to the inner bottom of the container body by welding.
[0014] Furthermore, the other end of the retractable elastic device is fixedly connected to the piston device by welding.
[0015] Optionally, the cross-sectional shape of the piston device is adapted to the internal cross-sectional shape of the container body, and the piston device is horizontally arranged in the container body.
[0016] Optionally, the retractable elastic device has an initial elastic force, and the initial elastic force is equal to the pressure generated in the first space when the precursor is in a saturated vapor pressure state.
[0017] Furthermore, the initial elastic force is 10N to 55N; and the saturated vapor pressure of the precursor is 0.1Torr to 0.4Torr.
[0018] As described above, the ALD precursor storage device of the utility model has the following beneficial effects: as the ALD reaction continues, when the saturated vapor pressure of the reactant gas is insufficient, the retractable elastic device can be extended at any time according to the vapor pressure value of the reactant gas in the container body to adjust the elastic force value, so that the pressure of the reactant gas received by the piston device on one side of the first space is equal to the elastic force of the retractable elastic device received by the piston device in the second space, thereby compressing the volume of the first space, so that the vapor pressure of the reactant gas increases. Therefore, even if the pressure gauge cannot timely feedback the actual pressure in the container body at this time, it can cooperate with the heating belt to make the reactant gas always in a state of saturated vapor pressure. It can effectively solve the problem of insufficient saturated vapor pressure of the reactant gas when the ALD deposition reaction is continuously carried out, improve the efficiency of transporting the reactant gas from the container body to the reaction chamber, thereby solving the problem of thin film thickness and poor film uniformity formed on the substrate in the same ALD deposition time. Finally, it reduces or even avoids the WAT failure and the impact on the performance of the integrated circuit caused by it. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a schematic diagram of an ALD precursor storage device in the prior art in which the gas formed by the precursor is under a saturated vapor pressure state at the initial stage of the ALD reaction.
[0020] Figure 2 It is a schematic diagram of an ALD precursor storage device in the prior art in which the gas formed by the precursor is in a non-saturated vapor pressure state in the middle stage of the ALD reaction.
[0021] Figure 3 It is a schematic diagram of an ALD precursor storage device in the prior art, in which the gas formed by the precursor is in a non-saturated vapor pressure state at the end of the ALD reaction.
[0022] Figure 4 It is a schematic diagram of the ALD precursor storage device of the present invention, showing the initial stage of the ALD reaction, when the gas generated by the precursor is in a saturated vapor pressure state.
[0023] Figure 5 It is a schematic diagram of the ALD precursor storage device of the present invention, showing the gas generated by the precursor in the middle stage of the ALD reaction, which is under the saturated vapor pressure state.
[0024] Figure 6It is a schematic diagram of the ALD precursor storage device of the present invention, showing the final stage of the ALD reaction, when the gas formed by the precursor is in a saturated vapor pressure state.
[0025] Component number description
[0026] 10, 20 Container body
[0027] 11, 21 Reactant solid
[0028] 12.22 Reactant gas
[0029] 13, 23 Intake pipe
[0030] 14, 24 Exhaust pipe
[0031] 25 Elastic mechanism
[0032] 200 First Space
[0033] 201 Second Space
[0034] 250 Retractable elastic device
[0035] 251 Piston device
[0036] 220 Ta-containing compound molecules
[0037] 221 Compound molecules containing N DETAILED DESCRIPTION
[0038] The following is a description of the implementation of the present invention by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.
[0039] See also Figures 1 to 6 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the utility model, so they have no substantial technical significance. Any modification of the structure, change in the proportion relationship, or adjustment of the size, without affecting the effects and purposes that can be achieved by the utility model, should still fall within the scope of the technical content disclosed by the utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the utility model. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the utility model without substantially changing the technical content.
[0040] As described in the background technology, based on the process principle of ALD technology, the reactant gas needs to be carried out under the condition of saturated vapor pressure to ensure the transport efficiency of the reactant gas from the container body to the reaction chamber and the uniformity of the ALD deposition process. In the process of depositing thin films using ALD technology, in order to maintain the reactant gas in the container body at a saturated vapor pressure, the prior art generally only adopts a method of surrounding the outer wall of the container body storing the ALD precursor with a heating belt to continuously heat the precursor, maintain or adjust the temperature of the reactant gas in the container body, and ensure that the reactant gas is carried out by the inert gas under the saturated vapor pressure and reacts on the substrate.
[0041] like Figures 1 to 3 The figure shows a schematic diagram of a storage device for storing ALD precursors in the prior art in different states when the ALD reaction is continuously carried out. The storage device includes a container body 10, an air inlet pipe 13 and an air outlet pipe 14. The ALD precursor is stored inside the container body 10, and the precursor includes a reactant solid 11 and a reactant gas 12, and the reactant solid 11 is accommodated at the bottom of the container body 10. A pressure gauge (not shown) is installed on the top of the container body 10, which is used to timely feedback the pressure condition in the container body 10, so as to adjust the vapor pressure of the reactant gas 12 in time. The outer wall of the container body 10 is surrounded by a heating belt (not shown), which is used to heat the reactant solid 11 and convert it into a reactant gas 12, and maintain or adjust the temperature of the reactant gas 12, so as to maintain the saturated vapor pressure of the reactant gas 12. The gas inlet pipe 13 is used to transport the inert gas, and the gas outlet pipe 14 is used for the inert gas to carry the reactant gas 12 to the reaction chamber to ensure a stable supply of the reactant gas 12 during the ALD process and achieve uniform thin film deposition.
[0042] like Figure 1 In the initial stage of the ALD reaction, the consumption of the reactant gas 12 is relatively small. The heating belt heats the reactant solid 11. The speed at which the reactant solid 11 is heated and converted into the reactant gas 12 is substantially equal to the speed at which the reactant gas 12 is consumed during ALD film deposition. The reactant gas 12 in the container body 10 is sufficient and is in a saturated vapor pressure state. The pressure gauge can timely feedback the actual pressure of the reactant gas 12, and the heating belt can maintain the saturated vapor pressure of the reactant gas 12.
[0043] like Figure 2It is the middle stage of the ALD reaction. As the ALD reaction proceeds, the consumption of the reactant gas 12 increases, and the rate at which the reactant solid 11 in the container body 10 is converted into the reactant gas 12 is gradually lower than the rate at which the reactant gas 12 is consumed during ALD film deposition. The reactant gas 12 in the container body 10 is insufficient, and the saturated vapor pressure of the reactant gas 12 is also insufficient. At this time, the pressure gauge cannot timely feedback the actual pressure of the reactant gas 12 due to its limited accuracy, and the heating belt cannot maintain the saturated vapor pressure of the reactant gas 12.
[0044] like Figure 3 At the end of the ALD reaction, as the ALD reaction continues, the consumption of the reactant gas 12 further increases, and the rate at which the reactant solid 11 in the container body 10 is converted into the reactant gas 12 is much lower than the rate at which the reactant gas 12 is consumed during ALD film deposition. The reactant gas 12 in the container body 10 decreases, and the vapor pressure of the reactant gas 12 further decreases. At this time, the pressure gauge cannot timely feedback the actual pressure of the reactant gas 12 due to its limited accuracy, and the heating belt cannot maintain the saturated vapor pressure of the reactant gas 12.
[0045] It can be seen that as the ALD reaction continues, the vapor pressure of the reactant gas 12 in the container body 10 decreases, the pressure gauge cannot timely feedback the actual pressure in the container body 10, and the heating belt has limited effect on maintaining the saturated vapor pressure of the precursor 12, resulting in insufficient saturated vapor pressure of the reactant gas 12, which reduces the efficiency of transporting the reactant gas 12 from the container body 10 to the reaction chamber, resulting in a thin film formed on the substrate within the same ALD deposition time, and poor film uniformity, which leads to WAT failure and may ultimately affect the performance of the integrated circuit.
[0046] Based on this, Figures 4 to 6 As shown, the utility model provides an ALD precursor storage device, the storage device comprising: a container body 20 and an elastic mechanism 25:
[0047] The elastic mechanism 25 is disposed at the lower part of the container body 20;
[0048] The elastic mechanism 25 includes a retractable elastic device 250 and a piston device 251; one end of the retractable elastic device 250 is fixed to the inner bottom of the container body 20, and the other end is connected to the piston device 251; the piston device 251 divides the internal space of the container body 20 into a first space 200 and a second space 201 along the up and down directions, and makes the second space 201 a sealed space, the retractable elastic device 250 is accommodated in the second space 201, and the precursor is accommodated in the first space 200; the piston device 251 can move up and down inside the container body 20 with the extension and compression of the retractable elastic device 250, so that the pressure on both sides of the piston device 251 is balanced.
[0049] The reaction process of the ALD precursor storage device of the present invention will be described in detail below with reference to specific drawings.
[0050] like Figures 4 to 6 The schematic diagram of the storage device of the ALD precursor of the utility model in different use states. The storage device includes: a container body 20, an air inlet pipe 23, an air outlet pipe 24 and an elastic mechanism 25. The precursor required for the ALD process is stored inside the container body 20, and the precursor includes a reactant solid 21 and a reactant gas 22. The elastic mechanism 25 is arranged at the lower part of the interior of the container body 20, and the elastic mechanism 25 includes a retractable elastic device 250 and a piston device 251. One end of the retractable elastic device 250 is fixed to the inner bottom of the container body 20, and the other end is connected to the piston device 251. The piston device 251 divides the internal space of the container body 20 into a first space 200 and a second space 201 along the up and down direction, and makes the second space 201 a sealed space. The retractable elastic device 250 is accommodated in the second space 201, and the precursor is accommodated in the first space 201. The piston device 251 can move up and down inside the container body 20 with the extension and compression of the retractable elastic device 250, so that the pressure on both sides of the piston device 251 is balanced. In practice, a pressure gauge (not shown) can be installed on the top of the container body 20 as needed to timely feedback the pressure condition in the storage device so as to timely adjust the vapor pressure of the reactant gas 22. In addition, a heating belt (not shown) can be wrapped around the outer wall of the container body 20 as needed to heat the reactant solid 21 and convert it into the reactant gas 22, and maintain or adjust the temperature of the reactant gas 22 to achieve the purpose of maintaining the saturated vapor pressure of the reactant gas 22.
[0051] The reactant gas 22 generally contains elements required by the target film material, and during the ALD process, they are introduced into the reaction chamber in an alternating pulse manner. Here, the ALD technique is used to deposit a tantalum nitride (TaN) film as an example, and the reactant gas 22 used includes Ta-containing compound molecules 220 and N-containing compound molecules 221.
[0052] The container body 20 can ensure the safety, stability and efficiency of the reactant gas 22 during storage and use. As an example, the container body 20 in this embodiment is a steel cylinder, the material of which is compatible with the ALD reactant gas 22 to prevent chemical reaction or corrosion, and the steel cylinder can withstand the higher pressure of the reactant gas 22 during storage and use.
[0053] The inlet pipe 23 is used to transport a carrier gas, which is generally an inert gas, and the outlet pipe 24 is used for the carrier gas to carry the reactant gas 22 to the reaction chamber to ensure a stable supply of the reactant gas 22 during the ALD process and achieve uniform film deposition. Preferably, the carrier gas used in the preparation of the tantalum nitride film in this embodiment is argon (Ar).
[0054] The retractable elastic device 250 is a component that can be retracted and restored to its original shape, usually made of elastic material, and is used to store and release energy. Preferably, the retractable elastic device 250 in this embodiment is a spring, the material of which is compatible with the precursor material and is not easily corroded.
[0055] One end of the retractable elastic device 250 can be fixedly connected to the bottom of the container body 20 by connection methods including but not limited to welding, embedded connection, threaded connection, special parts connection, elastomer embedded connection and adhesive connection. Preferably, in this embodiment, the retractable elastic device 250 is fixed to the bottom of the container body 20 by welding, so that the position of the retractable elastic device 250 is not easily shifted during extension and compression, thereby improving the sealing between the piston device 251 and the inner wall of the container body 20.
[0056] The other end of the telescopic elastic device 250 can be connected to the piston device 251 by connection methods including but not limited to piston center hole connection, piston rod connection, snap ring fixation, pin connection, welding and adhesive connection. Preferably, in this embodiment, the telescopic elastic device 250 is fixedly connected to the piston device 251 by welding, so that the positions of the telescopic elastic device 250 and the piston device 251 are not easily offset when the telescopic elastic device 250 is extended and compressed, thereby improving the sealing between the piston device 251 and the inner wall of the container body 20.
[0057] As a preferred example, the elastic mechanism 25 includes more than two retractable elastic devices 250, and all the retractable elastic devices 250 are evenly accommodated in the second space 201. This allows the piston device 251 to be evenly stressed when the retractable elastic device 250 is extended and compressed, thereby improving the sealing between the piston device 251 and the inner wall of the container body 20.
[0058] In order to make the second space 201 a sealed space, the cross-sectional shape of the piston device 251 is set to adapt to the internal cross-sectional shape of the container body 20, and the piston device 251 is horizontally arranged in the container body 20, and a sealing ring or piston ring is arranged on the outside of the piston device 251 to improve the sealing between the piston device 251 and the inner wall of the container body 20.
[0059] The materials of the components of the elastic mechanism 25 must be compatible with the reactant gas 22 and not easily corroded.
[0060] In the initial state or the initial stage of the ALD reaction, the reactant gas 22 is in a state of saturated vapor pressure. The retractable elastic device 250 is configured to be compressed and have an initial elastic force, so that the piston device 251 is subjected to the pressure of the reactant gas 22 on one side of the first space 200 and the elastic force of the retractable elastic device 250 in the second space 201. At this time, the initial elastic force of the retractable elastic device 250 is equal to the pressure generated in the first space 200 when the precursor is in a state of saturated vapor pressure.
[0061] like Figure 4 In the initial state or the initial stage of the ALD reaction, the consumption of the reactant gas 22 is small, the heating belt heats the reactant solid 21, and the speed of the reactant solid 21 being heated and converted into the reactant gas 22 is substantially equal to the speed of the reactant gas 22 being consumed during the ALD film deposition. The reactant gas 22 in the container body 10 is sufficient, the reactant gas 22 is in a saturated vapor pressure state, and the pressure gauge can timely feedback the actual pressure of the reactant gas 22, and the heating belt can maintain the saturated vapor pressure of the reactant gas 22. At this time, the initial elastic force of the retractable elastic device 250 is equal to the pressure generated in the first space 200 when the precursor is in a saturated vapor pressure state. As an example, according to the temperature and pressure conditions of the ALD reaction, the saturated vapor pressure of the precursor in this embodiment is 0.1Torr~0.4Torr, and the initial elastic force is set to 10N~55N.
[0062] like Figure 5In the middle stage of the ALD reaction, as the ALD reaction proceeds, the consumption of the reactant gas 22 increases, the speed at which the reactant solid 21 in the container body 20 is converted into the reactant gas 22 is lower than the speed at which the reactant gas 22 is consumed during the ALD film deposition, the reactant gas 22 in the container body 20 is insufficient, and the saturated vapor pressure of the reactant gas 22 is also insufficient. At this time, the pressure gauge cannot timely feedback the actual pressure of the reactant gas 22 due to limited accuracy, and the heating belt cannot maintain the saturated vapor pressure of the reactant gas 22. At this time, the piston device 251 is subjected to a decrease in the pressure of the reactant gas 22 on one side of the first space 200. Due to the unbalanced force on both sides of the piston device 251, the retractable elastic device 250 is extended, and the piston device 251 moves perpendicularly to the bottom of the container body 20 toward the top of the container body 20, compressing the volume of the first space 200, and the vapor pressure of the reactant gas 22 increases accordingly, and finally the reactant gas 22 is in a state of saturated vapor pressure.
[0063] like Figure 6 At the end of the ALD reaction, as the ALD reaction continues, the consumption of the reactant gas 22 further increases. The speed at which the reactant solid 21 in the container body 20 is converted into the reactant gas 22 is much slower than the speed at which the reactant gas 22 is consumed during ALD film deposition. The reactant gas 22 in the container body 20 is seriously insufficient, and the saturated vapor pressure of the reactant gas 22 is also seriously insufficient. At this time, the pressure gauge cannot timely feedback the actual pressure of the reactant gas 22 due to limited accuracy, and the heating belt cannot maintain the saturated vapor pressure of the reactant gas 22, resulting in the piston device 251 receiving the pressure of the reactant gas 22 on one side of the first space 200 continuously decreasing. Due to the unbalanced force on both sides of the piston device 251, the retractable elastic device 250 continues to extend, and the piston device 251 moves perpendicularly to the bottom of the container body 20 toward the top of the container body 20, the volume of the first space 200 decreases, and the vapor pressure of the reactant gas 22 increases, so that the reactant gas 22 is finally in a state of saturated vapor pressure.
[0064] It can be seen that as the ALD reaction continues, when the saturated vapor pressure of the reactant gas 22 is insufficient, the retractable elastic device 250 can be extended at any time according to the vapor pressure value of the reactant gas 22 in the container body 20 to adjust the elastic force value, thereby compressing the volume of the first space 200, so that the vapor pressure of the reactant gas 22 increases. Therefore, even if the pressure gauge cannot timely feedback the actual pressure in the container body 20 at this time, it can cooperate with the heating belt to make the reactant gas 22 always in a state of saturated vapor pressure.
[0065] In summary, the ALD precursor storage device provided by the utility model, as the ALD reaction continues, when the saturated vapor pressure of the reactant gas is insufficient, the retractable elastic device can be extended at any time according to the vapor pressure value of the reactant gas in the container body to adjust the elastic force value, so that the pressure of the reactant gas received by the piston device on one side of the first space is equal to the elastic force of the retractable elastic device received by the piston device in the second space, thereby compressing the volume of the first space, so that the vapor pressure of the reactant gas increases. Therefore, even if the pressure gauge cannot timely feedback the actual pressure in the container body at this time, it can cooperate with the heating belt to make the reactant gas always in a state of saturated vapor pressure. It can effectively solve the problem of insufficient saturated vapor pressure of the reactant gas when the ALD deposition reaction is continuously carried out, improve the efficiency of transporting the reactant gas from the container body to the reaction chamber, thereby solving the problem of thin film thickness and poor film uniformity formed on the substrate in the same ALD deposition time caused by this. Finally, the WAT failure and the impact on the performance of the integrated circuit caused by this are reduced or even avoided. Therefore, the utility model effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.
[0066] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention shall still be covered by the claims of the present invention.
Claims
1. An ALD precursor storage device, characterized in that: The storage device comprises: a container body and an elastic mechanism; The elastic mechanism is arranged at the lower part of the interior of the container body; The elastic mechanism includes a retractable elastic device and a piston device; one end of the retractable elastic device is fixed to the inner bottom of the container body, and the other end is connected to the piston device; the piston device divides the internal space of the container body into a first space and a second space along the up and down directions, and makes the second space a sealed space, the retractable elastic device is accommodated in the second space, and the precursor is accommodated in the first space; the piston device can move up and down inside the container body with the extension and compression of the retractable elastic device, so that the pressure on both sides of the piston device is balanced.
2. The ALD precursor storage device according to claim 1, characterized in that: The container body is a steel cylinder.
3. The ALD precursor storage device according to claim 1, characterized in that: The retractable elastic device is a spring.
4. The ALD precursor storage device according to claim 1, characterized in that: The outer side wall of the container body is surrounded by a heating belt.
5. The ALD precursor storage device according to any one of claims 1 to 4, characterized in that: The elastic mechanism includes more than two retractable elastic devices, and all the retractable elastic devices are evenly accommodated in the second space.
6. The ALD precursor storage device according to claim 5, characterized in that: One end of the retractable elastic device is fixedly connected to the inner bottom of the container body by welding.
7. The ALD precursor storage device according to claim 5, characterized in that: The other end of the retractable elastic device is fixedly connected to the piston device by welding.
8. The ALD precursor storage device according to claim 1, wherein: The cross-sectional shape of the piston device is adapted to the internal cross-sectional shape of the container body, and the piston device is horizontally arranged in the container body.
9. The ALD precursor storage device according to claim 1, characterized in that: The retractable elastic device has an initial elastic force, and the initial elastic force is equal to the pressure generated in the first space when the precursor is in a saturated vapor pressure state.
10. The ALD precursor storage device according to claim 9, characterized in that: The initial elastic force is 10N to 55N; The saturated vapor pressure of the precursor is 0.1 Torr to 0.4 Torr.