In-situ liquid chip with flow guide column structure and in-situ transmission electron microscope thereof

Abstract

The present disclosure relates to the field of in-situ liquid chip, and particularly relates to an in-situ liquid chip with flow guide column structure and an in-situ transmission electron microscope thereof. The in-situ liquid chip comprises: an upper chip; a lower chip comprising a second substrate, an upper surface of the second substrate being covered with a third insulating film layer, an electrode being arranged on the third insulating film layer, a liquid inlet and a liquid outlet being arranged on the lower chip, a plurality of flow guide columns being arranged on the third insulating film layer between the liquid inlet and the liquid outlet, a lower surface of the upper chip and an upper surface of the lower chip being sealingly joined to form a liquid storage cavity, the liquid inlet, the liquid outlet and the liquid storage cavity being in fluid communication, and the electrode being at least partially located in the liquid storage cavity. The present disclosure can introduce a flow guide column structure, guide the flow direction of the liquid by shunting and eliminate the accumulation of the liquid, so that the liquid can flow accurately.

Description

Technical Field

[0001] This disclosure relates to the field of in-situ liquid chips, specifically to in-situ liquid chips with flow-guiding column structures and their in-situ transmission electron microscopes. Background Technology

[0002] In-situ transmission electron microscopy (InSituTEM) technology, with its advantages of ultra-high spatial resolution (atomic level) and ultra-fast temporal resolution (millisecond level), is widely used in various scientific fields, providing researchers with new ideas and research methods for exploring the microstructure of novel materials. Currently, InSituTEM technology, by modifying the sample holder of the transmission electron microscope (TEM) and replacing the original copper mesh micrograting with an in-situ TEM environmental chip, introduces multiple physical fields such as force, heat, gas, light, electricity, and liquid, enabling in-situ observations under various environments.

[0003] Specifically, the in-situ liquid phase chip of transmission electron microscopy can form a closed in-situ reaction chamber. By introducing liquid into it, researchers can observe catalytic reactions, redox reactions, electrochemical reactions, low-dimensional material growth / synthesis, and various corrosion reactions in the in-situ reaction chamber in real time at the atomic scale, thus making it possible to analyze and study the dynamic processes of materials in liquids at the nanoscale.

[0004] Transmission electron microscopy (TEM) in-situ liquid phase chips involve multiple disciplines and are technically challenging with stringent fabrication requirements. They require the flow of liquid on micrometer-sized septa while ensuring the liquid volume meets observational requirements, presenting a significant challenge. The in-situ reaction chamber typically requires an observation window. Researchers use an electron beam to penetrate the window and interact with the liquid to acquire images and information about the liquid sample. Silicon nitride, due to its high hardness, high heat resistance, washability, high corrosion resistance, low coefficient of thermal expansion, and high transparency, has been widely used as a thin film material for forming these observation windows. However, because the in-situ reaction chamber operates under a high vacuum, the strength of the ultrathin silicon nitride layer limits the amount of liquid flowing into the chamber; otherwise, it risks damaging the ultrathin observation window. Furthermore, guiding the liquid precisely to the observation window area and preventing liquid accumulation due to uneven flow rates also limit the application of TEM in-situ liquid phase chips in certain liquid environments.

[0005] Japanese Patent Application Publication No. 2016-110877 (publication date: June 20, 2016) discloses a liquid phase chip in which an opening 110 is formed in a first substrate 10 and an opening 120 is formed in a second substrate 20. The side of the opening 110 adjacent to the second substrate 20 is closed by a first thin film 150, and the side of the opening 210 adjacent to the first substrate 10 is closed by a second thin film 250. The first thin film 150 and the second thin film 250 are formed, for example, by silicon nitride. In this disclosed solution, the silicon nitride film is at risk of being damaged due to excessive liquid in the reaction chamber, and the liquid in the reaction chamber is also prone to accumulation.

[0006] US Patent Application Publication US20200240933A1 (publication date: July 30, 2020) describes an electron microscope liquid chip with excellent anti-foaming capabilities. It uses hexagonal boron nitride (BN) and graphene instead of silicon nitride to prepare a substrate opening-sealing film to improve film strength. However, it does not reveal whether other physical properties of hexagonal boron nitride (BN) or graphene films are suitable for preparing the observation window of the in-situ liquid chip and achieving good observation results. Therefore, the aforementioned materials that replace silicon nitride may lead to other unpredictable risks during the operation of the in-situ liquid chip.

[0007] As can be seen from the above, how to make the observation window of the in-situ liquid chip of the transmission electron microscope able to withstand more liquid through appropriate design, while guiding the liquid to flow precisely to the observation window area and avoiding liquid accumulation, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0008] This disclosure provides an in-situ liquid chip with a flow guide column structure and its in-situ transmission electron microscope. By introducing the flow guide column structure, the flow direction of the liquid is guided and the liquid accumulation is eliminated through flow diversion, thereby enabling the liquid to flow precisely and to withstand a higher liquid inlet flow rate than a structure without a flow guide column, thus solving the problems of liquid accumulation mentioned in the background art.

[0009] As one aspect of this disclosure, an in-situ liquid chip with a flow-guiding column structure is provided, comprising:

[0010] The upper chip includes a first substrate, in which a first through hole penetrates its upper and lower surfaces. The upper surface of the first substrate is covered with a first insulating film layer, and the lower surface of the first substrate and the opening of the first through hole on the lower surface of the first substrate are both covered with a second insulating film layer.

[0011] The lower chip includes a second substrate, the upper surface of which is covered with a third insulating film layer. Electrodes are disposed on the third insulating film layer. The lower chip also has a liquid inlet and a liquid outlet, which penetrate the second substrate and the third insulating film layer. A plurality of flow guide columns are disposed on the third insulating film layer between the liquid inlet and the liquid outlet, wherein the plurality of flow guide columns are arranged in a shape to guide liquid from the liquid inlet to the liquid outlet.

[0012] The lower surface of the upper chip and the upper surface of the lower chip are sealed together to form a liquid storage cavity. The first through hole is located opposite to the liquid storage cavity. The liquid inlet and liquid outlet are in fluid communication with the liquid storage cavity. The electrode is located at least partially inside the liquid storage cavity.

[0013] Optionally, the second substrate has a second through hole penetrating its upper and lower surfaces, the upper surface of the second substrate and the opening of the second through hole on the upper surface of the second substrate are both covered with a third insulating film layer, the lower surface of the second substrate is covered with a fourth insulating film layer, and the position of the second through hole corresponds to the liquid storage cavity.

[0014] Optionally, the third insulating film layer is further provided with a partition located outside the liquid inlet and the liquid outlet, the upper end of the partition being sealed and joined with the upper chip to form the liquid storage cavity.

[0015] Optionally, the number of the guide columns is four, and the guide columns form two sets of figure-eight guide components in pairs along the direction from the liquid inlet to the liquid outlet.

[0016] Optionally, the flared end of the figure-eight flow guide component on the inlet side faces the inlet, and the constricted end faces the outlet; the flared end of the figure-eight flow guide component on the outlet side faces the outlet, and the constricted end faces the inlet.

[0017] Optionally, the sealing and joining method of the lower surface side of the upper chip and the upper surface side of the lower chip is selected from any one of thermo-press bonding, surface modification bonding, ultrasonic bonding, and adhesive bonding.

[0018] Optionally, the electrode is made of a metallic conductive material, which includes any one or a combination of two or more of gold, silver, copper, conductive adhesive, lithium, magnesium, aluminum, and platinum.

[0019] Optionally, the first substrate and the second substrate are silicon-based substrates.

[0020] Optionally, the second insulating film layer and the third insulating film layer are formed of silicon nitride.

[0021] Optionally, the first insulating film layer and / or the fourth insulating film layer are formed of silicon nitride.

[0022] As one aspect of this disclosure, an in-situ transmission electron microscope is provided, including the aforementioned in-situ liquid chip with a flow-guiding column structure.

[0023] Optionally, the in-situ transmission electron microscope includes a sample holder for fixing the in-situ liquid core.

[0024] Optionally, it also includes an O-ring disposed between the sample rod and the in-situ liquid chip for cushioning when the two are fixed together.

[0025] Compared to existing technologies, the advantages of this disclosure are as follows: Due to the presence of the flow guide column structure, upon contact with the liquid, it guides the flow direction of the liquid and eliminates liquid accumulation through the diversion and Venturi effects, thereby enabling the liquid to flow rapidly and precisely, and allowing it to withstand higher liquid inlet flow rates than structures without flow guide columns. Therefore, the in-situ liquid chip for transmission electron microscopy with the added flow guide column structure can withstand higher liquid flow rates and is suitable for in-situ TEM observations in environments with high liquid inlet flow rates. Attached Figure Description

[0026] Figure 1 This is a cross-sectional view of the upper chip in an embodiment of this disclosure;

[0027] Figure 2 This is a cross-sectional view of the lower chip in an embodiment of this disclosure;

[0028] Figure 3 This is a cross-sectional view of the chip mounted on the TEM sample holder in an embodiment of this disclosure;

[0029] Figure 4 This is a diagram of the lower chip structure in an embodiment of this disclosure. Detailed Implementation

[0030] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the disclosure will be further described below in conjunction with specific embodiments and accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] It should be understood that the terms "upper", "lower", "front", "back", "left", "right", "horizontal", "top", "inner", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element 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 of this disclosure.

[0032] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, unless otherwise stated, "a set" means two or more.

[0033] As one aspect of this disclosure, an in-situ liquid chip with a flow-guiding column structure is provided, such as... Figure 1-4 As shown, it includes:

[0034] The upper chip 1 includes a first substrate 1-1, the first substrate 1-1 having a first through hole 1-3 penetrating its upper and lower surfaces, the upper surface of the first substrate 1-1 being covered with a first insulating film layer, and the lower surface of the first substrate and the opening of the first through hole 1-3 on the lower surface of the first substrate 1-1 being covered with a second insulating film layer 1-2.

[0035] The lower chip 2 includes a second substrate 2-1, the upper surface of which is covered with a third insulating film layer 2-2. Electrodes 2-6 are disposed on the third insulating film layer 2-2. The lower chip 2 also has a liquid inlet 2-4 and a liquid outlet 2-5, which penetrate the second substrate 2-1 and the third insulating film layer 2-2. A plurality of flow guide columns 2-3 are disposed on the third insulating film layer 2-2 between the liquid inlet 2-4 and the liquid outlet 2-5. The plurality of flow guide columns 2-3 are arranged in a shape to guide liquid from the liquid inlet 2-4 to the liquid outlet 2-5.

[0036] The lower surface of the upper chip 1 and the upper surface of the lower chip 2 are sealed together to form a liquid storage cavity. The first through hole 1-3 is located opposite to the liquid storage cavity. The liquid inlet 2-4 and the liquid outlet 2-5 are in fluid communication with the liquid storage cavity. The electrode 2-6 is at least partially located in the liquid storage cavity.

[0037] The embodiments of this disclosure, implemented using the above method, can guide the flow direction of the liquid and eliminate liquid accumulation by diverting it upon contact with the liquid, thereby enabling precise liquid flow and allowing it to withstand higher liquid inlet flow rates than structures without guide pillars 2-3. The first substrate 1-1 and the second substrate 2-1 are silicon-based substrates, and the first through-hole 1-3 or the second through-hole can be formed by etching the silicon-based substrate with potassium hydroxide (KOH). The electrode 2-6 is made of a metallic conductive material, including any one or a combination of two or more of gold, silver, copper, conductive adhesive, lithium, magnesium, aluminum, and platinum. The electrode pattern can be fabricated by sputtering metal using a metal sputtering process followed by a lift-off process.

[0038] In a preferred embodiment, the number of electrodes 2-6 is at least two, and they are spaced apart from each other.

[0039] In a preferred embodiment, the second substrate 2-1 has a second through-hole penetrating its upper and lower surfaces. The upper surface of the second substrate 2-1 and the opening of the second through-hole on its upper surface are both covered by a third insulating film layer 2-2. The lower surface of the second substrate 2-1 is covered by a fourth insulating film layer. The position of the second through-hole corresponds to the liquid storage cavity. The second insulating film layer 1-2 and the third insulating film layer 2-2 are formed of silicon nitride to serve as observation windows. The silicon nitride film layer can be grown on the surface of a polished silicon substrate using a low-pressure chemical vapor deposition (LPCVD) process. The first insulating film layer and the fourth insulating film layer can also be prepared using this process.

[0040] In a preferred embodiment, the third insulating film layer 2-2 is further provided with a partition 2-7 located outside the liquid inlet 2-4 and the liquid outlet 2-5, the upper end of the partition 2-7 being sealed and joined with the upper chip 1 to form the liquid storage cavity.

[0041] In a preferred embodiment, there are four flow guide columns 2-3, and the flow guide columns 2-3 form two sets of "eight"-shaped flow guide components in pairs along the direction from the inlet to the outlet. The flared end of the "eight"-shaped flow guide component on the inlet 2-4 side faces the inlet 2-4, and the constricted end faces the outlet 2-5; the flared end of the "eight"-shaped flow guide component on the outlet 2-5 side faces the outlet 2-5, and the constricted end faces the inlet 2-4. Both the spacer 2-7 and the flow guide columns 2-3 can be grown with silicon oxide (e.g., 100 nm) using plasma-enhanced chemical vapor deposition (PECVD), and then the silicon oxide in the unwanted areas can be etched by wet etching, thus leaving the pattern of the spacer 2-7 and the flow guide columns 2-3. Compared with the prior art, the present invention, implemented in the above manner, can utilize the diversion effect and Venturi effect of the "eight"-shaped flow guiding component to guide the flow and increase the fluid velocity when the liquid is introduced into the inlet 2-4, so that the liquid is quickly guided to the observation window and no liquid accumulation occurs. It is suitable for in-situ TEM observation in environments with high liquid inlet flow rates.

[0042] In a preferred embodiment, the sealing and bonding method of the lower surface side of the upper chip and the upper surface side of the lower chip is selected from any one of thermo-press bonding, surface modification bonding, ultrasonic bonding, and adhesive bonding.

[0043] In a preferred embodiment, the size of the first through hole 1-3 gradually increases along the direction away from the lower surface side of the upper chip 1.

[0044] In a preferred embodiment, the size of the second through hole gradually increases along the direction away from the upper surface side of the lower chip 2.

[0045] As another aspect of the present disclosure, an in-situ transmission electron microscope is also provided, including the in-situ liquid chip with the flow-guiding column 2-3 structure in the above embodiments.

[0046] In a preferred embodiment, the in-situ transmission electron microscope further includes a sample rod 3, which is used to fix the in-situ liquid chip.

[0047] In a preferred embodiment, an O-ring 4 is also included, disposed between the sample rod 3 and the in-situ liquid chip, for cushioning when the two are fixed together.

[0048] The embodiments described above merely illustrate the preferred implementation of this disclosure, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent disclosure. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this disclosure, and these all fall within the protection scope of this disclosure. Therefore, the protection scope of this patent disclosure should be determined by the appended claims.

Claims

1. An in-situ liquid chip with a flow-guiding column structure, characterized in that, include: The upper chip includes a first substrate, in which a first through hole penetrates its upper and lower surfaces. The upper surface of the first substrate is covered with a first insulating film layer, and the lower surface of the first substrate and the opening of the first through hole on the lower surface of the first substrate are both covered with a second insulating film layer. The lower chip includes a second substrate, the upper surface of which is covered with a third insulating film layer. Electrodes are disposed on the third insulating film layer. The lower chip also has a liquid inlet and a liquid outlet, which penetrate the second substrate and the third insulating film layer. A plurality of flow guide columns are disposed on the third insulating film layer between the liquid inlet and the liquid outlet, wherein the plurality of flow guide columns are arranged to guide liquid from the liquid inlet to the liquid outlet. The lower surface of the upper chip and the upper surface of the lower chip are sealed together to form a liquid storage cavity. The first through hole is located opposite to the liquid storage cavity. The liquid inlet and liquid outlet are in fluid communication with the liquid storage cavity. The electrode is located at least partially inside the liquid storage cavity. The number of guide columns is 4, and the guide columns form two sets of "eight"-shaped guide components in pairs along the direction from the liquid inlet to the liquid outlet.

2. The in-situ liquid chip with a flow-guiding column structure as described in claim 1, characterized in that, The second substrate has a second through hole penetrating its upper and lower surfaces. The upper surface of the second substrate and the opening of the second through hole on the upper surface of the second substrate are both covered with a third insulating film layer. The lower surface of the second substrate is covered with a fourth insulating film layer. The position of the second through hole corresponds to the liquid storage cavity.

3. The in-situ liquid chip with a flow-guiding column structure as described in claim 1 or 2, characterized in that, The third insulating film layer is also provided with a partition located outside the liquid inlet and the liquid outlet, and the upper end of the partition is sealed and joined with the upper chip to form the liquid storage cavity.

4. The in-situ liquid chip with a flow-guiding column structure as described in claim 3, characterized in that, The flared end of the figure-eight flow guide component on the inlet side faces the inlet, and the constricted end faces the outlet; the flared end of the figure-eight flow guide component on the outlet side faces the outlet, and the constricted end faces the inlet.

5. The in-situ liquid chip with a flow-guiding column structure as described in any one of claims 1-2 and 4, characterized in that, The sealing and joining method of the lower surface side of the upper chip and the upper surface side of the lower chip is selected from any one of thermo-pressing bonding, surface modification bonding, ultrasonic bonding, and adhesive bonding. The electrode is made of a metallic conductive material, which includes any one or a combination of two or more of gold, silver, copper, conductive adhesive, lithium, magnesium, aluminum, and platinum. The first substrate and the second substrate are silicon-based substrates.

6. The in-situ liquid chip with a flow-guiding column structure as described in any one of claims 1-2 and 4, characterized in that, The second insulating film layer and the third insulating film layer are formed of silicon nitride.

7. The in-situ liquid chip with a flow-guiding column structure as described in claim 2, characterized in that, The first insulating film layer and / or the fourth insulating film layer are formed of silicon nitride.

8. An in-situ transmission electron microscope, characterized in that, Including the in-situ liquid chip with a flow-guiding column structure as described in any one of claims 1-7.

9. The in-situ transmission electron microscope as described in claim 8, characterized in that, The in-situ transmission electron microscope includes a sample rod for fixing the in-situ liquid core, and an O-ring disposed between the sample rod and the in-situ liquid chip for cushioning when the two are fixed together.

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