TWI816302B - Liquid cell microchip and manufacturing method thereof - Google Patents

Abstract

The invention provides a liquid cell microchip used in an electron microscope, which comprises a first substrate having a first groove, a second substrate having a second groove, the first substrate is combined with the second substrate, and the first groove and the second groove are arranged face to face to define a space, the first groove contains a water repellent surface and the second groove contains a hydrophilic surface.

Description

Liquid measurement slide and production method thereof

The present invention relates to the field of semiconductor manufacturing processes, and in particular to a structure of a liquid measurement slide suitable for electron microscopes and a manufacturing method thereof.

Scanning material layers using electron microscopes such as a transmission electron microscope (TEM) or a scanning electron microscope (SEM) is one of the common processes. In addition to being used for solid material layers, the above-mentioned electronic scanning can also be used to scan liquid films to observe various solution states. For example, in the semiconductor field, it can be used to observe the particle size in grinding fluids or solvents, or in biotechnology. In the field, it can be used to observe the status of cells in various biological fluids, etc., which are currently developing applications.

Since the high-energy electron beam emitted by an electron microscope will cause the liquid to volatilize, when observing a liquid with an electron microscope, the liquid must be filled into a liquid measuring slide before observation. The liquid measurement slide is composed of an upper and lower slide. After filling the liquid to be scanned into the flow channel space between the two slides, the liquid measurement slide is packaged and sent to an electron microscope for scanning. Since the liquid is located in the sealed liquid measurement slide, there is no evaporation of the liquid.

However, among current technologies, the process technology of using electron microscopes to scan liquids still needs to be improved. space, such as improving scanning resolution, simplifying scanning steps, or reducing scanning costs. The above-mentioned technological development is one of the research and development goals in this field.

For example, Figure 1 shows a schematic cross-sectional view of a conventional liquid measurement slide. The liquid measurement slide 1 is composed of two slide substrates 2, each of which has a groove. , align the grooves with each other and combine to form a flow channel space 3, then pour the liquid 4 to be observed into the flow channel space 3, and then send it to an electron microscope for observation.

The applicant found that the current liquid measurement slide has a problem, that is, the thickness of the flow channel space 3 affects the thickness of the liquid 4 (i.e., the thickness of the liquid film). If the thickness of the flow channel space 3 is designed to be thicker, it will cause As the liquid film becomes thicker, the resolution under electron microscope observation becomes worse. However, if the thickness of the flow channel space 3 is designed to be thinner, although the resolution of the liquid film under electron microscope observation can be improved, if the flow channel space is If the thickness is too thin, some liquids (such as cell fluids, highly viscous grinding fluids, etc.) will not be easily poured into the flow channel space, and may even cause blockage. Therefore, there is still room for improvement on the above problems.

Therefore, the present invention provides an improved liquid measurement slide that can be used in the scanning steps of various electron microscopes. The present invention also provides a method for producing the above-mentioned liquid measurement slide.

The invention provides a liquid measuring slide used in an electron microscope, which includes a first slide including a first groove, a second slide including a second groove, wherein the first slide and the third slide are The two slides are combined, and the first groove and the second groove are arranged face to face to define a flow channel space, wherein the first groove includes a water-repellent surface, and the second groove includes a hydrophilic surface.

The present invention also provides a method for making a liquid measurement slide for use in an electron microscope, which includes providing a first slide, forming a first groove on the first slide, providing a second slide, and A second groove is formed on the second carrier chip to combine the first carrier chip and the second carrier chip, and the first groove and the second groove are arranged face to face to define a flow channel space, wherein the first groove contains There is a water-repellent surface, and the second groove contains a hydrophilic surface.

The characteristic of the present invention is that the inner surfaces of the grooves in the two slides of the liquid measurement slide are processed by different processes, resulting in a difference in hydrophilicity and hydrophobicity in the flow channel space. In this way, when the liquid is poured into the flow channel space, if the liquid itself is hydrophilic, the liquid will only adhere to the hydrophilic side and not the water-repellent side. In this way, the thickness of the liquid film can be significantly reduced, so that when measuring liquids with an electron microscope, the resolution can be greatly increased without causing the problem of liquid clogging.

1: Liquid measurement slide

2: Slide base

3:Flow channel space

4: liquid

10: First slide

12: First groove

14: Silicon nitride layer

16: Silicon oxide layer

20: Second slide

22: Second groove

24: Silicon nitride layer

30:Flower space

40:Liquid

41:Liquid

42:gap

P1: First processing step

P2: Second processing step

T1: Depth

T2: Depth

W: water drop

θ1: Contact angle

θ2: Contact angle

Figure 1 shows a schematic cross-sectional view of a conventional liquid measuring slide.

Figures 2 to 3 are schematic structural views of a liquid measurement slide according to the first embodiment of the present invention.

Figure 4 shows a schematic diagram of a pure water droplet located on a hydrophilic surface and a water-repellent surface.

Figures 5 and 6 are schematic structural views of a liquid measurement slide according to the first embodiment of the present invention.

Figure 7 is a schematic structural diagram of a liquid measurement slide according to the second embodiment of the present invention.

Figure 8 is a schematic structural diagram of a liquid measurement slide according to the third embodiment of the present invention.

In order to enable those familiar with the technical field of the present invention to further understand the present invention Clearly, the preferred embodiments of the present invention are enumerated below, and the composition and intended effects of the present invention are described in detail with reference to the accompanying drawings.

For convenience of explanation, each drawing of the present invention is only schematic to make it easier to understand the present invention, and its detailed proportions can be adjusted according to design requirements. The upper and lower relationships between relative elements in the figures described in the text should be understood by those in the art to refer to the relative positions of the objects. Therefore, they can all be flipped over to present the same components, and these should all belong to the scope of this specification. The scope of disclosure will be explained here first.

Figures 2 to 3 illustrate the structural schematic diagram of making a liquid measurement slide of the present invention. The liquid measurement slide provided by the present invention is composed of two slides with basically the same or similar structure. First, please refer to FIG. 2 , which provides a first carrier chip 10 and a second carrier chip 20 , where the material of the first carrier chip 10 and the second carrier chip 20 is, for example, silicon. Then, the first groove 12 is formed on the first carrier chip 10 and the second groove 22 is formed on the second carrier chip 20 by etching or other methods. In this embodiment, the depths of the first groove 12 and the second groove 22 are both about 1 micron, but are not limited thereto. Then, a silicon nitride layer 14 and a silicon nitride layer 24 are formed on the first carrier chip 10 and the second carrier chip 20 respectively. The purpose of forming the silicon nitride layer 14 here is that the silicon nitride layer 14 can be used as an etching stop layer for forming an observation window in subsequent steps. This part of the technical content is a common technology in the art and will not be described again here.

Next, as shown in FIG. 3 , different processing steps are performed on the grooves of the first carrier 10 and the second carrier 20 , including performing a first processing step P1 on the first carrier 10 and performing a second processing step P1 on the first carrier 10 . The slide undergoes a second processing step P2. The first processing step P1 is, for example, applying oxygen plasma to the silicon nitride layer 14 so that a silicon oxide layer 16 is regenerated on the surface of the silicon nitride layer 14. The thickness of the silicon oxide layer 16 is about 12 Angstroms, but is not limited to this. After the silicon oxide layer 16 is formed, the surface is rich in silicon-oxygen bonds. On the other hand, the second processing step P2 applies a nitrogen/hydrogen-containing plasma to the silicon nitride layer 24 so that the silicon nitride layer 24 surface The number of silicon-nitrogen bonds on the surface increases. The purpose of performing the first processing step P1 and the second processing step P2 here is to perform different surface treatments on the silicon nitride layer 14 and the silicon nitride layer 24 respectively, so as to change the hydrophilicity or Water repellent. Furthermore, after the first processing step P1 is performed, the silicon oxide layer 16 is regenerated on the surface of the silicon nitride layer 14 and its hydrophilicity is improved, and after the second processing step P2 is performed, the silicon-oxide layer 16 on the surface of the silicon nitride layer 24 is The number of nitrogen bonds is increased and water repellency is improved.

The definitions of hydrophilicity and hydrophobicity described here can be referred to Figure 4. Figure 4 shows a schematic diagram of a pure water droplet located on a hydrophilic surface and a water-repellent surface. When a pure water droplet W falls on a hydrophilic surface (left side of Figure 4), the contact angle θ1 between the water droplet W and the hydrophilic surface is preferably less than 5 degrees; in contrast, when the pure water droplet W falls on a repellent surface On the water surface (right side of Figure 4), the contact angle θ2 between the water droplet W and the water-repellent surface is preferably greater than 35 degrees.

In addition, although some conventional techniques define surfaces with contact angles less than 90 degrees as hydrophilic surfaces, and surfaces with contact angles greater than 90 degrees are called hydrophobic surfaces (such as lotus leaf surfaces). However, "hydrophilic" and "water-repellent" described in the present invention are relative concepts in comparison and are not limited by the above common understanding. For example, the contact angle θ1 of the hydrophilic surface in this embodiment is preferably less than 5 degrees, which is a relatively hydrophilic surface, while the contact angle θ2 between the water-repellent surfaces is preferably greater than 35 degrees, which is " Less hydrophilic” surface. As long as the contact angle difference between the hydrophilic surface and the water-repellent surface of the present invention can reach more than 30 degrees, the effect of liquid only adhering to one side can be achieved in subsequent steps. In addition, choosing a hydrophilic surface with a smaller contact angle will help reduce the thickness of the liquid film, thus improving the resolution under electron microscopy.

It is worth noting that according to the applicant's observation and experiment, if the contact angle is directly measured without any treatment after the silicon nitride layer 24 is formed, the contact angle between the silicon nitride layer 24 and the pure water droplets is approximately 10-30 degrees. That is to say, the present invention can improve the silicon-nitride content on the surface of the silicon nitride layer 24 through nitrogen/hydrogen plasma treatment. Although the number of nitrogen bonds does not form other different material layers on the surface of the silicon nitride layer 24, it still helps to improve the water repellency (increase the contact angle to more than 35 degrees), which is beneficial to creating a connection with the first groove 12 differences in hydrophilic surfaces.

In the above steps, surface treatment is used to change the surface conditions of the silicon nitride layer 14 and the silicon nitride layer 24. In other embodiments of the present invention, the change can also be achieved by other means (such as coating or deposition, etc.) The effects of hydrophilicity and water repellency, and other methods to achieve hydrophilicity/water repellency differences between the inner surfaces of the first groove 12 and the second groove 22 are all within the scope of the present invention.

Please continue to refer to Figure 5. The first slide 10 and the second slide 20 that have undergone the first processing step P1 and the second processing step respectively in Figure 3 are combined with each other, wherein the first groove 12 and the second groove 22 are aligned face to face with each other, and the closed space composed of the first groove 12 and the second groove 22 is defined as the flow channel space 30 . In this embodiment, the thickness of the flow channel space 30 is about 2 microns, which is the sum of the depths of the first groove 12 and the second groove 22 . The characteristic of the present invention is that part of the inner surface of the flow channel space 30 is made of a hydrophilic material (such as the silicon oxide layer 16), and another part of the inner surface is made of a water-repellent material (such as through nitrogen/hydrogen gas). Silicon nitride layer after plasma treatment 24). That is to say, the internal surface of the flow channel space 30 has differences in hydrophilicity or water repellency.

Please refer to Figure 6. After the liquid 40 under observation is injected into the flow channel space, if the liquid 40 is an aqueous liquid or contains an aqueous solvent, the liquid 40 will adhere to the hydrophilic surface and will not easily adhere to the water-repellent surface. Therefore, The liquid film does not fill the entire flow channel space 30. The thickness of the liquid film can be significantly reduced, and the resolution of the liquid film under electron microscope observation is effectively improved. At the same time, part of the flow channel space 30 is not filled with the liquid film and remains. There are gaps 42, so if the liquid 40 itself has high viscosity or contains particles, the liquid 40 will not be easily blocked in the flow channel space 30. Through the structure and manufacturing method provided by the present invention, the problem can be solved In traditional technology, in order to improve the resolution and reduce the thickness of the flow channel space, it may cause liquid blockage, or to design the flow channel space thicker to avoid blockage but reduce the resolution.

On the other hand, please refer to FIG. 7 , which is a schematic structural diagram of a liquid measurement slide according to the second embodiment of the present invention. In this embodiment, if the liquid 41 is not an aqueous liquid (for example, an oily solvent), the liquid 41 may not adhere to the hydrophilic surface, but in this case the liquid 41 will adhere to the water-repellent surface. Due to the difference in hydrophilicity/water repellency within the flow channel space 30, the liquid film thickness can be reduced regardless of whether the liquid 41 itself is an aqueous liquid.

In another embodiment of the present invention, the depths of the first groove 12 and the second groove 22 can be designed to be different depths. For example, as shown in Figure 8, the depth T1 of the first groove 12 and the depth of the second groove 22 can be designed to be different depths. The depth T2 of 22 is not equal, so that the thickness of the liquid film and the thickness of the gap can be further controlled. For example, if the depth T1 of the first groove 12 is designed to be smaller (less than 1 micron), the film thickness of the hydrophilic liquid can be further reduced and the resolution of the liquid film under an electron microscope can be improved. If the depth T2 of the second groove 22 is designed to be larger (greater than 1 micron), after the liquid is poured into the flow channel space, the remaining gap 42 in the flow channel space can be increased to avoid clogging problems such as particles.

Based on the above description and drawings, the present invention provides a liquid measuring slide for use in an electron microscope, which includes a first slide 10 including a first groove 12 and a second slide 20 including a second Groove 22, in which the first carrier 10 and the second carrier 20 are combined, and the first groove 12 and the second groove 22 are arranged face to face to define a flow channel space 30, wherein the first groove 12 contains a The second groove 22 contains a hydrophilic surface, while the second groove 22 contains a water-repellent surface.

In some embodiments of the present invention, the hydrophilic surface of the first groove 12 is in contact with a pure water The contact angle between drops W is less than 5 degrees.

In some embodiments of the present invention, the contact angle between the water-repellent surface of the second groove 22 and a pure water droplet W is greater than 35 degrees.

In some embodiments of the present invention, the material of the hydrophilic surface includes silicon oxide, and the material of the water-repellent surface includes silicon nitride.

In some embodiments of the present invention, a depth T1 of the first groove 12 is less than a depth T2 of the second groove 22 .

The present invention also provides a method for manufacturing a liquid measurement slide for use in an electron microscope, which includes providing a first slide 10, forming a first groove 12 on the first slide 10, and providing a second slide. piece 20, and a second groove 22 is formed on the second carrier piece 20, the first carrier piece 10 and the second carrier piece 20 are combined, and the first groove 12 and the second groove 22 are arranged face to face to define Out of the flow channel space 30, the first groove 12 contains a hydrophilic surface, and the second groove 22 contains a hydrophobic surface.

In some embodiments of the present invention, the manufacturing method further includes performing an oxygen plasma treatment on the first groove 12 to increase the hydrophilicity of the surface of the first groove 12 .

In some embodiments of the present invention, the manufacturing method further includes performing a hydrogen and nitrogen plasma treatment on the second groove to improve the water repellency of the surface of the second groove.

In some embodiments of the invention, a depth of the first groove 12 is equal to the depth of the second groove 22 ’s depth is equal.

In some embodiments of the present invention, a depth of the first groove 12 is not equal to a depth of the second groove 22 .

The characteristic of the present invention is that the groove surfaces in the two carrier substrates of the liquid measurement carrier are processed by different processes, resulting in a difference in hydrophilicity and hydrophobicity in the flow channel space. In this way, when the liquid is poured into the flow channel space, if the liquid itself is hydrophilic, the liquid will only adhere to the hydrophilic side and not the water-repellent side. Therefore, the thickness of the liquid film can be significantly reduced, so that when measuring liquids with an electron microscope, the resolution can be greatly increased without causing the problem of liquid clogging.

The above are only preferred embodiments of the present invention, and all equivalent changes and modifications made in accordance with the patentable scope of the present invention shall fall within the scope of the present invention.

10: First slide

14: Silicon nitride layer

16: Silicon oxide layer

20: Second slide

24: Silicon nitride layer

30:Flower space

40:Liquid

42:gap

Claims (10)

A liquid measuring slide used in an electron microscope, including: a first slide including a first groove; a second slide including a second groove, wherein the first slide and the third slide are The two slides are combined, and the first groove and the second groove are arranged face to face to define a flow channel space, wherein the first groove contains a hydrophilic surface, and the second groove contains a water-repellent surface. surface; and a liquid and a void simultaneously located in the flow channel space. In the liquid measuring slide used in an electron microscope as described in item 1 of the patent application, the contact angle between the hydrophilic surface of the first groove and a pure water droplet is less than 5 degrees. In the liquid measuring slide used in an electron microscope as described in item 1 of the patent application, the contact angle between the water-repellent surface of the second groove and a pure water droplet is greater than 35 degrees. As described in item 1 of the patent application, for the liquid measuring slide used in an electron microscope, the material of the hydrophilic surface includes silicon oxide, and the material of the water-repellent surface includes silicon nitride. As described in claim 1 of the patent application, a liquid measuring slide for use in an electron microscope is provided, wherein a depth of the first groove is smaller than a depth of the second groove. A method for making a liquid measuring slide for use in an electron microscope, including: providing a first slide and forming a first groove on the first slide; providing a second slide and forming a first groove on the first slide; A second groove is formed on the two carrier sheets; the first carrier sheet and the second carrier sheet are combined, and the first groove and the second groove are arranged face to face, so as to Define a flow channel space, wherein the first groove includes a hydrophilic surface, and the second groove includes a water-repellent surface; and provide a liquid to be poured into the flow channel space, wherein the flow channel space is more A gap is included, and the liquid and the gap are located in the flow channel space at the same time. The manufacturing method of a liquid measurement slide for use in an electron microscope as described in item 6 of the patent application, wherein the manufacturing method further includes performing an oxygen plasma treatment on the first groove to make the first groove The hydrophilicity of the surface of the groove is improved. As described in Item 6 of the patent application, the manufacturing method of a liquid measurement slide for use in an electron microscope further includes performing a hydrogen and nitrogen plasma treatment on the second groove to make the second groove The water repellency of the surface of the second groove is improved. As described in Item 6 of the patent application, the method for manufacturing a liquid measuring slide used in an electron microscope, wherein a depth of the first groove is equal to a depth of the second groove. As described in Item 6 of the patent application, the method for manufacturing a liquid measuring slide used in an electron microscope, wherein a depth of the first groove is smaller than a depth of the second groove.

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