Array substrate, microfluidic device, microfluidic system, and fluorescence detection method

Abstract

An array substrate, a microfluidic device, a microfluidic system and a fluorescence detection method. The array substrate (100) comprises at least one recessed portion (103), wherein the array substrate is located in a plane, and the ratio of the area of ​​the orthographic projection of the at least one recessed portion on the plane to the area of ​​the orthographic projection of the array substrate on the plane is between 0.05 and 0.60. This area ratio can enable the array substrate to have recessed portions with an appropriate number and an appropriate chamber volume.

Description

Technical Field

[0001] The present disclosure relates to the field of biomedical detection, and particularly to an array substrate, a microfluidic device including the array substrate, a microfluidic system including the microfluidic device, and a fluorescence detection method. Background Art

[0002] Polymerase Chain Reaction (PCR) is a molecular biology technique for amplifying specific DNA fragments, which can replicate trace amounts of deoxyribonucleic acid (DNA) in large quantities, significantly increasing its quantity. Digital Polymerase Chain Reaction (dPCR) technology is a quantitative analysis technique developed on the basis of PCR that can provide digital DNA quantification information. Its combination with microfluidic technology has greatly improved sensitivity and precision. In this dPCR technology, nucleic acid samples are fully diluted so that the number of target molecules (i.e., DNA templates) in each reaction unit is less than or equal to 1. PCR amplification is performed on the target molecules in each reaction unit respectively. After the amplification is completed, statistical analysis is performed on the fluorescence signals of each reaction unit, thereby realizing absolute quantitative detection of single-molecule DNA. Due to the advantages of high sensitivity, strong specificity, relatively high detection throughput, and accurate quantification, dPCR is widely used in fields such as clinical diagnosis, gene instability analysis, single-cell gene expression, environmental microorganism detection, and prenatal diagnosis. Summary of the Invention

[0003] According to one aspect of the present disclosure, there is provided an array substrate, which includes at least one recess. The array substrate is located in a plane, and the ratio of the area of the positive projection of the at least one recess on the plane to the area of the positive projection of the array substrate on the plane is between 0.05 and 0.60.

[0004] In some embodiments, the array substrate further includes: a first substrate; a defining layer located on the first substrate, which defines the at least one recess; and a shielding layer, which defines at least one opening. The positive projection of the at least one opening on the first substrate and the positive projection of the at least one recess on the first substrate at least partially overlap, and the positive projection of the shielding layer on the first substrate and the positive projection of the defining layer on the first substrate at least partially overlap.

[0005] In some embodiments, the at least one recess penetrates through the defining layer.

[0006] In some embodiments, the shielding layer is located between the first substrate and the defining layer.

[0007] In some embodiments, the blocking layer is located on a side of the first substrate away from the defining layer.

[0008] In some embodiments, the shielding layer includes a first portion, the first portion is located on a side of the defining layer away from the first substrate and attached to a side surface of the defining layer and a surface away from the first substrate. The first portion defines the at least one opening.

[0009] In some embodiments, the shielding layer further includes a second portion, the second portion being attached to a surface of the defining layer close to the first substrate to surround the defining layer together with the first portion, and the second portion defining the at least one opening.

[0010] In some embodiments, an orthographic projection of the at least one opening defined by the first portion of the shielding layer on the first substrate completely overlaps with an orthographic projection of the at least one opening defined by the second portion of the shielding layer on the first substrate.

[0011] In some embodiments, a surface of the defining layer close to the first substrate and / or a surface of the defining layer far from the first substrate constitute the shielding layer.

[0012] In some embodiments, a tangent line at any point on the side wall of the at least one recessed portion forms an angle with the plane on which the array substrate is located, and the angle is not equal to 90°.

[0013] In some embodiments, the defining layer defines a plurality of recessed portions, the shielding layer defines a plurality of openings, the plurality of recessed portions correspond one-to-one to the plurality of openings, and an orthographic projection of each of the plurality of openings on the first substrate is located within an orthographic projection of a recessed portion corresponding to the opening on the first substrate.

[0014] In some embodiments, a shape of an orthographic projection of each of the at least one recess and each of the at least one opening on the first substrate includes a circle or a regular polygon.

[0015] In some embodiments, the limiting layer defines a plurality of recessed portions, and the shielding layer defines a plurality of openings, the plurality of recessed portions correspond to the plurality of openings one by one, and the orthographic projection of each of the plurality of openings on the first substrate is located within the orthographic projection of a recessed portion corresponding to the opening on the first substrate. The shapes of the orthographic projections of each opening and the recessed portion corresponding to the opening on the first substrate are both circular, the diameter of each opening is in the range of 20 to 80 μm, and the diameter of the recessed portion corresponding to the opening is in the range of 25 to 90 μm; or, the shape of the orthographic projection of each opening on the first substrate is a first regular polygon, the shape of the orthographic projection of the recessed portion corresponding to the opening on the first substrate is a second regular polygon, the diameter of the inscribed circle of the first regular polygon is in the range of 20 to 80 μm, and the diameter of the inscribed circle of the second regular polygon is in the range of 25 to 90 μm.

[0016] In some embodiments, the material of the definition layer includes photoresist.

[0017] In some embodiments, the material of the shielding layer includes a light-proof material, and the light-proof material includes chromium, chromium oxide, and black resin.

[0018] In some embodiments, the thickness of the shielding layer in a direction perpendicular to the first substrate is in the range of 0.6 to 2.4 μm.

[0019] In some embodiments, the array substrate further includes a heating electrode located between the first substrate and the defining layer, and the heating electrode is configured to heat the at least one recessed portion.

[0020] In some embodiments, the material of the heating electrode includes indium tin oxide.

[0021] In some embodiments, the heating electrode includes a plurality of sub-portions separated from each other.

[0022] In some embodiments, the array substrate further includes a conductive layer. The conductive layer is located between the first substrate and the heating electrode and is electrically connected to the heating electrode, and an orthographic projection of at least a portion of the conductive layer on the first substrate falls on the periphery of an orthographic projection of the heating electrode on the first substrate, and the conductive layer at least partially surrounds the heating electrode.

[0023] In some embodiments, the array substrate further comprises a hydrophilic layer and a first hydrophobic layer, wherein the hydrophilic layer at least covers a sidewall of the at least one recessed portion, and the first hydrophobic layer is located on a side of the limiting layer away from the first substrate and further away from the first substrate than the hydrophilic layer.

[0024] In some embodiments, the hydrophilic layer further covers a surface of the defining layer away from the first substrate and a bottom of the at least one recessed portion.

[0025] In some embodiments, the first hydrophobic layer defines a plurality of holes, the defining layer defines a plurality of recessed portions, and the shielding layer defines a plurality of openings, and the plurality of holes, the plurality of recessed portions, and the plurality of openings correspond to each other one by one. The first orthographic projection of each of the plurality of holes on the first substrate and the third orthographic projection of an opening corresponding to the hole on the first substrate are both located within the second orthographic projection of a recessed portion corresponding to the hole on the first substrate, and the first orthographic projection, the second orthographic projection, and the third orthographic projection form concentric rings. The first orthographic projection is located between the second orthographic projection and the third orthographic projection, and the third orthographic projection is located within the first orthographic projection.

[0026] In some embodiments, a ratio of an area of ​​the first hydrophobic layer to an area of ​​the hydrophilic layer is between 0.01 and 2.00.

[0027] According to another aspect of the present disclosure, a microfluidic device is provided, which includes an array substrate described in any of the above embodiments, an opposing substrate that is aligned with the array substrate, and a spacer between the array substrate and the opposing substrate. The opposing substrate includes: a second substrate; and a second hydrophobic layer located on a side of the second substrate close to the first substrate. The opposing substrate includes at least one through hole that penetrates the second substrate and the second hydrophobic layer.

[0028] In some embodiments, the material of the first substrate and the second substrate includes glass.

[0029] In some embodiments, the second hydrophobic layer comprises a light absorbing material, and the light absorbing material comprises TiO 2 and at least one of TiON.

[0030] According to another aspect of the present disclosure, a microfluidic system is provided, the microfluidic system comprising a control device and the microfluidic device described in any of the above embodiments. The control device is electrically connected to the microfluidic device and is configured to control the temperature of the microfluidic device.

[0031] According to another aspect of the present disclosure, a fluorescence detection method is provided, which includes: accommodating a reagent to be detected in at least one recessed portion of a microfluidic device described in any of the foregoing embodiments; allowing light of a first wavelength emitted by a light source to irradiate the at least one recessed portion through at least one opening defined by the shielding layer; and detecting light of a second wavelength emitted by the reagent to be detected. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly describe the technical solutions in the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 A partial cross-sectional view of an array substrate provided according to an embodiment of the present disclosure is shown;

[0034] Figure 2 A partial cross-sectional view of an array substrate provided according to an embodiment of the present disclosure is shown;

[0035] Figure 3 A partial plan view of a shielding layer and a defining layer having a recessed portion in an array substrate provided according to an embodiment of the present disclosure is shown;

[0036] Figure 4 A top view of a defining layer having a recessed portion defined in an array substrate provided according to an embodiment of the present disclosure is shown;

[0037] Figure 5 A top view of an array substrate provided according to an embodiment of the present disclosure is shown;

[0038] Figure 6 A plan view of a part of the structure in the array substrate provided according to an embodiment of the present disclosure is shown;

[0039] Figure 7 A partial cross-sectional view of an array substrate provided according to another embodiment of the present disclosure is shown;

[0040] Figure 8 A partial cross-sectional view of an array substrate provided according to another embodiment of the present disclosure is shown;

[0041] Figure 9 A partial cross-sectional view of an array substrate provided according to yet another embodiment of the present disclosure is shown;

[0042] Figure 10 A partial cross-sectional view of a microfluidic device provided according to an embodiment of the present disclosure is shown;

[0043] Figure 11 A block diagram of a microfluidic system provided according to an embodiment of the present disclosure is shown;

[0044] Figure 12 A flow chart of a fluorescence detection method provided according to an embodiment of the present disclosure is shown;

[0045] Figure 13A schematic diagram showing a fluorescence detection process of a microfluidic device provided according to an embodiment of the present disclosure is shown;

[0046] Figure 14A shows a fluorescence picture of a microfluidic device in the related art after being irradiated by a light source; and

[0047] Figure 14B A fluorescence picture of the microfluidic device provided in an embodiment of the present disclosure after being irradiated by a light source is shown. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present disclosure will be described clearly and completely below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0049] Since dPCR technology has the advantages of high sensitivity, strong specificity, high detection flux, and accurate quantification, it is widely used in clinical diagnosis, gene instability analysis, single-cell gene expression, environmental microbial detection, and prenatal diagnosis. In the application of dPCR, after completing the PCR amplification of the reaction system solution in each reaction chamber in the microfluidic device, it is usually necessary to use a certain wavelength of excitation light to perform fluorescence detection on the reagents to be detected in each reaction chamber. However, the inventors found that in conventional microfluidic devices, since the area occupied by all reaction chambers is much smaller than the area of ​​the microfluidic device, that is, each reaction chamber has a very small volume, the reaction system solution in each reaction chamber cannot fully perform an amplification reaction, thereby obtaining a smaller dose of the reagent to be detected. This reagent to be detected, which is far lower than the required dose, cannot radiate the desired fluorescence intensity under the irradiation of the excitation light, thereby seriously affecting the fluorescence detection accuracy of the reagent to be detected in the reaction chamber, and then causing the obtained fluorescence detection results to fail to meet the diagnostic requirements in the biomedical field (such as single cell analysis, early cancer diagnosis, and prenatal diagnosis).

[0050] It should be noted that, in this specification, "reagents to be detected" refers to the reagents after the reaction system solution in the microfluidic device undergoes polymerase chain reaction, that is, the reaction system reagents after the amplification reaction is completed.

[0051] Based on this, the embodiments of the present disclosure provide an array substrate, a microfluidic device, a microfluidic system and a fluorescence detection method. The array substrate can improve the fluorescence detection accuracy of a reagent to be detected in a microfluidic device including the array substrate.

[0052] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that the same reference numerals in different drawings will be used to refer to the same elements that have been described.

[0053] According to one aspect of the present disclosure, an array substrate 100 is provided. Figure 1 FIG. 1 shows a partial cross-sectional view of the array substrate 100. Figure 2 Another cross-sectional view of the array substrate 100 is shown ( Figure 2 It is along Figure 5 A-A' line cut off the cross section), Figure 3 FIG. 1 shows a plan view of a part of the structure of the array substrate 100. Figures 1 to 3 , the array substrate 100 includes at least one recessed portion 103, the array substrate 100 is located in a plane, and the ratio of the area of ​​the orthographic projection of the at least one recessed portion 103 on the plane to the area of ​​the orthographic projection of the array substrate 100 on the plane is between 0.05 and 0.60. For example, the ratio of the area of ​​the orthographic projection of the at least one recessed portion 103 on the plane to the area of ​​the orthographic projection of the array substrate 100 on the plane can be 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60. It should be noted that, in this article, "the plane where the array substrate 100 is located" refers to the plane where the array substrate 100 as a whole is located, and the array substrate 100 extends in the plane. In some examples, the number of the at least one recessed portion 103 can be 2000~1000000. In some examples, the number of at least one recessed portion 103 may be 40,000 to 100,000. In one example, the number of at least one recessed portion 103 is 22,500. The shape of the orthographic projection of each recessed portion 103 on the plane where the array substrate 100 is located may be any appropriate shape such as a circle, an ellipse, a rectangle, a square, a triangle, a regular hexagon, a polygon (such as a regular polygon), an irregular shape, or the like.

[0054] The recessed portion 103 is used to contain a reaction system solution (such as a DNA molecule), and the reagent to be detected is obtained after the reaction system solution is amplified by the dPCR technology. The inventor of the present application designs the area ratio of the multiple recessed portions 103 and the array substrate 100 so that the two have a suitable area ratio relationship, that is, the ratio of the area of ​​the orthographic projection of the multiple recessed portions 103 on the plane where the array substrate 100 is located to the area of ​​the orthographic projection of the array substrate 100 on the plane is between 0.05 and 0.60, so that the array substrate 100 can have an appropriate number of recessed portions 103 with an appropriate chamber volume, so that the reaction system solution contained in each recessed portion 103 can undergo a sufficient dPCR reaction, improve the utilization rate of the reaction system solution, and thus obtain more doses of the reagent to be detected after amplification. This dose of the test reagent can radiate a desired fluorescence intensity under the irradiation of the excitation light, thereby improving the fluorescence detection accuracy of the test reagent, so that the obtained fluorescence detection results can meet the diagnostic requirements in the biomedical field (such as single cell analysis, early cancer diagnosis and prenatal diagnosis).

[0055] Continue to refer Figures 1 to 3 The array substrate 100 further includes: a first substrate 101; a defining layer 102 located on the first substrate 101, the defining layer 102 defining the at least one recessed portion 103; and a shielding layer 104 defining at least one opening 105. The orthographic projection of the at least one opening 105 on the first substrate 101 at least partially overlaps with the orthographic projection of the at least one recessed portion 103 on the first substrate 101, and the orthographic projection of the shielding layer 104 on the first substrate 101 at least partially overlaps with the orthographic projection of the defining layer 102 on the first substrate 101.

[0056] It should be noted that, in this specification, phrases such as "the defining layer 102 defines the at least one recessed portion 103" mean that the defining layer 102 includes or has at least one recessed portion 103, and the recessed portion 103 is formed by patterning the defining layer 102, for example, by drilling holes in the defining layer 102 to obtain a plurality of recessed portions 103. In addition, it should be noted that, although described as a defining layer 102 and a shielding layer 104 in this specification, the defining layer 102 and the shielding layer 104 can be two independent film layer structures or the same film layer structure. In some embodiments, the defining layer 102 and the shielding layer 104 are two independent film layer structures, the defining layer 102 is formed by a film layer of a suitable material, and the shielding layer 104 is formed by another film layer having a light-shielding property. In an alternative embodiment, the defining layer 102 and the shielding layer 104 are the same film layer structure, for example, by physically or chemically treating a portion of the defining layer 102 (for example, the surface of the defining layer 102 close to the first substrate 101 and / or the surface of the defining layer 102 away from the first substrate 101) to make it opaque, so that the portion of the defining layer 102 serves as the shielding layer 104; and the remaining untreated portion of the defining layer 102 continues to serve as the defining layer 102.

[0057] Make the excitation light of a certain wavelength go from bottom to top (i.e. Figure 1 The excitation light is irradiated to the recessed portion 103 through the opening 105 defined by the shielding layer 104) in the direction from the first substrate 101 to the limiting layer 102, so that the reagent with fluorescent properties in the recessed portion 103 is excited and emits a fluorescence spectrum. The limiting layer 102 in the array substrate 100 usually also emits undesired fluorescence after being irradiated with the excitation light due to its inherent material properties. However, in the embodiment of the present disclosure, by providing the shielding layer 104 and making the orthographic projection of the shielding layer 104 on the first substrate 101 overlap with the orthographic projection of the limiting layer 102 on the first substrate 101 at least partially, when the excitation light is irradiated to the recessed portion 103 through the opening 105, the shielding layer 104 can at least partially shield the limiting layer 102 so that it is not irradiated by the excitation light, thereby preventing the limiting layer 102 from being irradiated by the excitation light and generating interfering fluorescence. In this way, the excitation light can only excite the reagent to be detected in the recessed portion 103 through the opening 105. Therefore, through such an arrangement, the fluorescence interference caused by the limiting layer 102 can be reduced or even avoided, so that the fluorescence signal emitted by the reagent to be detected in the recessed portion 103 can be accurately identified by the detector, so that the reaction signal can be read more sensitively and accurately, the fluorescence detection accuracy of the reagent to be detected can be improved, and image data support can be provided for the data analysis of the subsequent nucleic acid amplification reaction. In addition, through such an arrangement, clearer microwell array imaging can be achieved, the detection error caused by false positives can be reduced, and the interference between different channels in the multi-channel fluorescence signal detection process can be well avoided.

[0058] It should be noted that "reagent with fluorescent properties" means that when the reagent is irradiated with excitation light of a specific wavelength, it will emit fluorescence with a wavelength longer than the excitation light in a short time. Under the irradiation of the excitation light of the specific wavelength, the reagent is more likely to emit fluorescence than other film layers in the array substrate 100.

[0059] The first substrate 101 plays a role in protecting and supporting the array substrate 100. The first substrate 101 can be made of any suitable material, such as a rigid material or a flexible material, and the rigid material or the flexible material includes but is not limited to glass, ceramic, silicon, polyimide and other materials. In one example, the first substrate 101 is made of glass, and the glass material can reduce the surface roughness of the first substrate 101, which is conducive to the movement of the reaction solution (such as a droplet) on the surface of the corresponding film layer.

[0060] The limiting layer 102 may be made of any suitable material. In some embodiments, the material of the limiting layer 102 is a photoresist. The photoresist may be formed on the first substrate 101 by any suitable means (e.g., spin coating), and patterned to form the limiting layer 102. The limiting layer 102 generally has a thicker thickness. In one example, the thickness of the limiting layer 102 may range from 5 microns to 100 microns, for example, 9.8 microns. The limiting layer 102 defines a plurality of recesses 103, and the plurality of recesses 103 are spaced apart from each other. Each recess 103 may penetrate the limiting layer 102, or may not completely penetrate the limiting layer 102. In the latter case, a portion of the limiting layer 102 is formed at the bottom of the recess 103. In an embodiment of the present disclosure, the recess 103 may penetrate the limiting layer 102. In this way, when the excitation light is irradiated to the recess 103 via the opening 105, the reagent in the recess 103 may be directly irradiated, thereby further improving the fluorescence detection accuracy of the reagent. The recessed portion 103 provides a space for the reaction system solution, and the reaction system solution moved into the recessed portion 103 will be relatively stably retained in the recessed portion 103. For example, the recessed portion 103 can be a groove, a notch, a micropore, etc., as long as it has a space capable of accommodating the reaction system solution, and the embodiments of the present disclosure are not limited to this.

[0061] The shapes of the multiple recessed portions 103 may be completely the same or partially different. In some embodiments, the shape of the positive projection of each recessed portion 103 on the first substrate 101 is circular. The three-dimensional shape of each recessed portion 103 is, for example, an approximate cylinder, that is, the cross section in the direction perpendicular to the first substrate 101 is an approximate rectangle and the cross section in the plane parallel to the first substrate 101 is an approximate circle. In some embodiments, the diameter of the bottom surface of the cylinder ranges from 1 micron to 100 microns, for example, 20 microns to 50 microns, 50 microns to 90 microns. The height of the cylinder ranges from 5 microns to 100 microns, for example, 30 microns to 50 microns. For example, in some examples, the bottom surface diameter of the cylinder is about 50 microns, the height of the cylinder is in the range of 40 microns to 50 microns, and the distance between the centers of two adjacent recessed portions 103 is about 100 microns.

[0062] The shape of the recessed portion 103 can be designed according to actual needs. For example, the shape of each recessed portion 103 can also be a truncated cone, a cuboid, a polygonal prism, a sphere, an ellipsoid, etc., and the embodiments of the present disclosure are not limited to this. For example, the cross-sectional shape of the recessed portion 103 on the plane parallel to the first substrate 101 can be an ellipse, a triangle, a polygon, an irregular shape, etc., and the cross-sectional shape in the direction perpendicular to the first substrate 101 can be a square, a circle, a parallelogram, a trapezoid, or other polygons, etc.

[0063] In some embodiments, the tangent line at any point on the side wall of each recessed portion 103 forms a certain angle with the plane on which the array substrate 100 is located, and the angle is not equal to 90°. In other words, the side wall of each recessed portion 103 is not perpendicular to the plane on which the array substrate 100 is located, but has a certain inclination, and the inclination angle can be, for example, an acute angle (greater than 0° and less than 90°) or an obtuse angle (greater than 90° and less than 180°). In one example, Figure 1 As shown, the side wall of the recessed portion 103 forms an obtuse angle with the plane where the array substrate 100 is located, and the inclination angle of the side wall makes the bottom area of ​​the recessed portion 103 smaller than the area of ​​the upper opening corresponding to the bottom. Of course, the shape of the recessed portion 103 is not limited to this. In another example, the side wall of the recessed portion 103 forms an acute angle with the plane where the array substrate 100 is located, and the inclination angle of the side wall makes the bottom area of ​​the recessed portion 103 larger than the area of ​​the upper opening corresponding to the bottom. By designing the side wall of the recessed portion 103 in this way, each recessed portion 103 can obtain a larger volume in a limited space, so that each recessed portion 103 can accommodate more reaction system solution, and then more doses of the reagent to be detected can be obtained after the amplification reaction, thereby improving the fluorescence emission intensity of the reagent to be detected, and then improving the fluorescence detection accuracy of the reagent to be detected.

[0064] It should be noted that the walls surrounding the concave portion 103 can be referred to as side walls of the concave portion 103. Figure 2 and Figure 3 As shown, the side wall of the recessed portion 103 is adjacent to the limiting layer 102, and the height of the side wall of the recessed portion 103 in the direction perpendicular to the first substrate 101 is substantially the same as the height of the limiting layer 102 in the direction perpendicular to the first substrate 101. The side wall of the recessed portion 103 and the bottom of the recessed portion 103 constitute a reaction chamber of the recessed portion 103 to accommodate the reagent to be detected. In addition, it should be noted that the side wall of the recessed portion 103 may be an inclined surface, an arc surface, or a curved surface with any curvature (e.g., a variable curvature), and the embodiment of the present disclosure does not specifically limit the shape of the side wall of the recessed portion 103.

[0065] Figure 3 Shows Figure 2 A plan view of the shielding layer 104 and the defining layer 102 defining the recessed portion 103, Figure 4 FIG. 1 shows a top view of a defining layer 102 defining a recessed portion 103 in an array substrate 100 . Figure 4 Each small circle in FIG. 1 represents a concave portion 103. Figure 3 and Figure 4 As shown, a plurality of recessed portions 103 are evenly distributed on the first substrate 101. For example, on the first substrate 101, a plurality of recessed portions 103 are arranged in an array in the horizontal direction and the vertical direction. This method can make the fluorescent image obtained when the microfluidic device including the array substrate 100 is optically detected in the subsequent stage more regular and neat, so as to obtain the detection result quickly and accurately. Of course, the embodiments of the present disclosure are not limited to this, and the plurality of recessed portions 103 may also be unevenly distributed on the first substrate 101, or arranged in other ways, and the embodiments of the present disclosure are not limited to this. The number of recessed portions 103 may be 2000~1000000. In some examples, the number of recessed portions 103 is 40000~100000. In one example, the number of recessed portions 103 is 22500. As a result, the array substrate 100 has a large detection flux.

[0066] It should be noted that, in the embodiments of the present disclosure, the size and number of the recessed portions 103 can be determined according to actual needs, and the size and number of the recessed portions 103 are related to the sizes of the first substrate 101 and the array substrate 100. When the size of the recessed portions 103 remains unchanged, the larger the number of the recessed portions 103, the larger the sizes of the first substrate 101 and the array substrate 100.

[0067] Since the target molecules (i.e., DNA molecules) in the reaction system solution are sufficiently diluted, when the reaction system solution enters each recess 103, the target molecules in each recess 103 are less than or equal to 1, that is, each recess 103 includes only one target molecule or no target molecule, so as to obtain accurate detection results in the subsequent stage.

[0068] like Figure 1 and Figure 2 As shown, the shielding layer 104 is located between the first substrate 101 and the defining layer 102. In one example, the shielding layer 104 is attached to the bottom surface of the defining layer 102 facing the first substrate 101. In one example, the orthographic projection of the defining layer 102 on the first substrate 101 completely falls within the orthographic projection of the shielding layer 104 on the first substrate 101, as shown in FIG. Figure 3 As shown. With such an arrangement, the excitation light incident through the opening 105 will not irradiate the limiting layer 102 at all. The shielding layer 104 can be made of any suitable material, as long as the material can block light or absorb light, and the embodiment of the present disclosure does not specifically limit the material of the shielding layer 104. In some embodiments, the material of the shielding layer 104 is an opaque material, which can be, for example, an opaque metal. In some examples, the material of the shielding layer 104 is a black matrix (BM) commonly used in the display field, and the material of the black matrix includes one or more of chromium, chromium oxide, and black resin. In some examples, the thickness of the shielding layer 104 in a direction perpendicular to the first substrate 101 is in the range of 0.6 microns to 2.4 microns, for example, 2 microns.

[0069] The shielding layer 104 defines a plurality of openings 105, and the plurality of openings 105 correspond to the plurality of recessed portions 103 one by one, and the orthographic projection of each opening 105 on the first substrate 101 is located within the orthographic projection of a recessed portion 103 corresponding to the opening 105 on the first substrate 101. That is, the area of ​​the orthographic projection of each opening 105 on the first substrate 101 is smaller than the area of ​​the orthographic projection of a recessed portion 103 corresponding to the opening 105 on the first substrate 101. With such an arrangement, during the subsequent fluorescence detection, the excitation light can only irradiate the recessed portion 103 through the opening 105, and will not irradiate the area around the recessed portion 103, thereby avoiding the interference of the film layer (such as part of the limiting layer 102) in the surrounding area near the recessed portion 103 on the fluorescence detection. In actual product design, the size of the opening 105 of the shielding layer 104 can be designed accordingly according to the size of the illumination spot of the incident excitation light, the thickness of the limiting layer 102, etc. It should be noted that terms such as "one-to-one correspondence between a plurality of A and a plurality of B" means that the number of A is equal to the number of B and each A corresponds to one B, and the orthographic projection of each A on the first substrate 101 at least partially overlaps with the orthographic projection of a B corresponding to the A on the first substrate 101. In some embodiments, the shape of each opening 105 and the corresponding recessed portion 103 may be the same or different. The shape of the opening 105 may be cylindrical, truncated cone, cuboid, polygonal prism, sphere, ellipsoid, etc., and the embodiments of the present disclosure are not limited to this. For example, the cross-sectional shape of the opening 105 on a plane parallel to the first substrate 101 may be an ellipse, triangle, polygon, irregular shape, etc., and the cross-section in a direction perpendicular to the first substrate 101 may be a square, circle, parallelogram, trapezoid, or other polygon. In one example, the orthographic projections of each opening 105 and a corresponding recess 103 on the first substrate 101 are both circular, and the diameter of each opening 105 is in the range of 20 to 80 microns, while the diameter of a recess 103 corresponding to the opening 105 is in the range of 25 to 90 microns. It should be noted that the diameter of the opening 105 is smaller than the diameter of the recess 103 corresponding thereto. For example, if the diameter of the opening 105 is 20 microns, the diameter of the recess 103 corresponding thereto may be 25 microns; if the diameter of the opening 105 is 60 microns, the diameter of the recess 103 corresponding thereto may be 70 microns; if the diameter of the opening 105 is 80 microns, the diameter of the recess 103 corresponding thereto may be 90 microns, and so on. In another example, the shape of the orthographic projection of each opening 105 on the first substrate 101 is a first regular polygon, the shape of the orthographic projection of a recess 103 corresponding to the opening 105 on the first substrate 101 is a second regular polygon, the diameter of the inscribed circle of the first regular polygon is in the range of 20 to 80 μm, and the diameter of the inscribed circle of the second regular polygon is in the range of 25 to 90 μm.It should be noted that the diameter of the inscribed circle of the first regular polygon is smaller than the diameter of the inscribed circle of the second regular polygon. For example, if the diameter of the inscribed circle of the first regular polygon is 20 microns, the diameter of the inscribed circle of the second regular polygon may be 25 microns; if the diameter of the inscribed circle of the first regular polygon is 60 microns, the diameter of the inscribed circle of the second regular polygon may be 70 microns; if the diameter of the inscribed circle of the first regular polygon is 80 microns, the diameter of the inscribed circle of the second regular polygon may be 90 microns, etc. By making the shapes of the opening 105 and the recessed portion 103 substantially the same and making the diameter of the opening 105 smaller than the diameter of the recessed portion 103, the excitation light can be irradiated to the recessed portion 103 with a higher utilization rate, and as described above, only the recessed portion 103 is irradiated without irradiating the surrounding area of ​​the recessed portion 103.

[0070] Since the shielding layer 104 is located between the first substrate 101 and the limiting layer 102, the orthographic projection of the shielding layer 104 on the first substrate 101 must overlap with the first substrate 101 itself, that is, the shielding layer 104 must shield at least part of the first substrate 101. Therefore, when the excitation light is irradiated to the recessed portion 103 via the opening 105 from the bottom to the top, the shielding layer 104 can not only block the excitation light from irradiating to the limiting layer 102, but also block the excitation light irradiated to the first substrate 101 from transmitting through the shielding layer 104, thereby not only avoiding the limiting layer 102 from emitting undesired fluorescence, but also at least partially reducing the trace amount of fluorescence interference (possibly) generated by the first substrate 101 after being irradiated by the excitation light. This further improves the fluorescence detection accuracy of the reagent in the recessed portion 103.

[0071] Although the above embodiment is described as two independent film structures of the limiting layer 102 and the shielding layer 104, as mentioned above, the limiting layer 102 and the shielding layer 104 may also be the same film structure. In the embodiment where the limiting layer 102 and the shielding layer 104 are the same film structure, the surface of the limiting layer 102 close to the first substrate 101 (i.e., the lower surface of the limiting layer 102) is physically or chemically treated to make it opaque, so that the lower surface of the limiting layer 102 acts as the shielding layer 104; and the remaining untreated portion of the limiting layer 102 continues to play the role of the limiting layer 102. When the recessed portion 103 penetrates the limiting layer 102 (that is, the recessed portion 103 is a structure similar to a through hole), the opening at the bottom of the recessed portion 103 is equivalent to the opening 105 of the shielding layer 104; when the recessed portion 103 does not completely penetrate the limiting layer 102 (that is, the recessed portion 103 is a structure similar to a blind hole), the lower surface of the limiting layer 102 is processed to form an opening at a position corresponding to the recessed portion 103, and the opening is equivalent to the opening 105 of the shielding layer 104.

[0072] During the dPCR reaction, the double-stranded structure of the DNA fragment denatures to form a single-stranded structure at high temperature (e.g. 90°C), the primer and the single strand are combined according to the base complementary pairing principle at low temperature (e.g. 65°C), and the base binding extension is achieved at the most suitable temperature of DNA polymerase (e.g. 72°C). The above process is the temperature cycle process of denaturation-annealing-extension. Through multiple temperature cycles of denaturation-annealing-extension, DNA fragments can be replicated in large quantities.

[0073] In order to realize the above-mentioned temperature cycle process, a series of external devices are usually required to heat and cool the microfluidic device including the array substrate 100, which makes the device bulky, complicated to operate, and high in cost. In addition, during the heating and cooling process of the microfluidic device, the overall temperature of the microfluidic device changes accordingly, so that the temperature of other structures and components in the microfluidic device except the recessed portion 103 for accommodating DNA fragments also changes accordingly, thereby increasing the risk of damage to components such as circuits. In addition, since there are usually tens of thousands to hundreds of thousands of recessed portions 103 distributed in the microfluidic device, the temperature of each recessed portion 103 will be uneven during the heating process of the microfluidic device, for example, the middle temperature of the reaction area (the area composed of each recessed portion 103) is higher and the edge temperature is lower, which will affect the entire dPCR process and make the final detection result of the reagent inaccurate.

[0074] In order to solve the above problems, Figure 1 and Figure 2 As shown, the array substrate 100 further includes a heating electrode 106 located between the first substrate 101 and the defining layer 102 , and the heating electrode 106 is configured to heat the plurality of recessed portions 103 .

[0075] The heating electrode 106 is located on the first substrate 101, and the heating electrode 106 can receive an electrical signal (such as a voltage signal), so that when a current flows through the heating electrode 106, heat is generated, and the heat is conducted to the recessed portion 103 for use in a polymerase chain reaction. For example, the heating electrode 106 can be made of a conductive material with a large resistivity, so that the heating electrode 106 can generate a large amount of heat when provided with a small electrical signal, so as to improve the energy conversion rate. The heating electrode 106 can be made of, for example, a transparent conductive material, such as indium tin oxide (ITO), tin oxide, etc., or other applicable materials, such as metals, etc., and the embodiments of the present disclosure are not limited to this.

[0076] As shown in the figure, the orthographic projections of the plurality of recesses 103 on the first substrate 101 are located within the orthographic projections of the heating electrode 106 on the first substrate 101. Here, the orthographic projection refers to the projection on the first substrate 101 in a direction perpendicular to the first substrate 101. For example, Figure 2As shown, in the direction perpendicular to the first substrate 101, the orthographic projections of the plurality of recesses 103 on the first substrate 101 are located within the orthographic projections of the heating electrode 106 on the first substrate 101, and the orthographic projections of the heating electrode 106 are larger than the orthographic projections of the plurality of recesses 103. In this way, the heating electrode 106 can heat each recess 103. Due to the edge heat dissipation effect of the heating electrode 106, the operating temperature at the edge of the heating electrode 106 is usually lower than the operating temperature of the central area thereof. By making the above projection of the heating electrode 106 larger than the above projections of the plurality of recesses 103, the central area of ​​the heating electrode 106 with uniform temperature can correspond to the plurality of recesses 103, thereby heating the plurality of recesses 103, so as to avoid heating the recesses 103 at the edge of the heating electrode 106 (for example, an area of ​​5 mm, 8 mm or other applicable sizes from the edge), thereby making the heating of the plurality of recesses 103 more uniform and having better temperature consistency, thereby facilitating the effective amplification reaction of the reaction system solution in the recess 103.

[0077] Figure 5 A plan view of the array substrate 100 is shown. As shown in the figure, the heating electrode 106 includes a plurality of sub-parts separated from each other and extending along a first direction X (i.e., the vertical direction in the figure). The figure shows five sub-parts separated from each other and insulated, but the embodiments of the present disclosure are not limited thereto, and may also include more or fewer sub-parts separated from each other, such as two sub-parts separated from each other, ten sub-parts separated from each other, one hundred sub-parts separated from each other, etc. The embodiments of the present disclosure do not limit the spacing between the sub-parts, as long as the product design requirements are met. In one example, the spacing between the sub-parts of the heating electrode 106 is in the range of 1 micron to 200 microns. By applying electrical signals to each sub-portion in the heating electrode 106 respectively, for example, applying a high voltage to one end of each sub-portion and applying a low voltage (for example, a ground signal) to the other end of each sub-portion, currents of substantially the same magnitude can flow through each of the sub-portions separated from each other in the heating electrode 106, and thus maintaining substantially the same temperature, thereby further improving the temperature uniformity of various parts of the heating electrode 106, making the heating of the multiple recessed portions 103 more uniform and the temperature consistency better, thereby further promoting the amplification reaction of the reaction system solution in the recessed portion 103.

[0078] exist Figure 5 In the figure, each sub-portion of the heating electrode 105 is shown as a long rectangular strip, but the embodiment of the present disclosure does not limit the shape of each sub-portion of the heating electrode 106, which can be any appropriate shape. For example, Figure 6Another possible planar shape of each sub-portion of the heating electrode 106 is shown. As shown in the figure, the heating electrode 106 includes a plurality of strip structures extending along the first direction X and separated from each other, and the width of the middle portion of each strip structure along the second direction Y is wider than the width of the two end portions of the strip structure along the second direction Y, and the second direction Y is a direction perpendicular to the first direction X in a plane parallel to the first substrate 101. Of course, the plurality of strip structures in the heating electrode 106 are not limited to Figure 6 The shape shown in the left part of the figure can be used as long as the shape of the strip structure makes the width of the middle part wider than the width of the two end parts. Figure 6 As shown on the right side of , the strip structure of the heating electrode 106 may also be in the shape of an ellipse or a rectangle with a broken line edge contour.

[0079] In the embodiment of the present disclosure, by providing the heating electrode 106 in the array substrate 100 (for example, integrating the heating electrode 106 on the first substrate 101), the heating of the recessed portion 103 of the array substrate 100 can be effectively realized, and the temperature control of the recessed portion 103 can be realized, without the need for external heating equipment, and the integration is high. By providing the heating electrode 106 as a plurality of sub-parts separated from each other, the temperature of each part of the heating electrode 106 can be kept substantially the same, thereby further improving the temperature uniformity of each part of the heating electrode 106, and making the heating of the plurality of recessed portions 103 more uniform. In addition, compared with some array substrates that need to drive the droplets to move so that they can pass through a plurality of temperature regions in sequence before they can be heated, the array substrate 100 can realize temperature cycling without driving the droplets, and the operation is simple and the production cost is low.

[0080] Return to continue reference Figure 1 and Figure 2 The array substrate 100 further includes a conductive layer 107 and a first insulating layer 110. The conductive layer 107 is located between the first substrate 101 and the heating electrode 106. The first insulating layer 110 is located between the conductive layer 107 and the heating electrode 106. The conductive layer 107 is electrically connected to the heating electrode 106 through a via 112 in the first insulating layer 110. The conductive layer 107 is configured to apply an electrical signal (e.g., a voltage signal) to the heating electrode 106. After receiving the electrical signal, the heating electrode 106 can generate heat under the action of the electrical signal, thereby heating the recessed portion 103. It should be noted that the first insulating layer 110 can also cover a portion of the first substrate 101 that is not blocked by the conductive layer 107.

[0081] The via hole 112 exposes a portion of the conductive layer 107, so that the heating electrode 106 can be electrically connected to the conductive layer 107 via the via hole 112. The shape of the via hole 112 can be cylindrical, truncated cone, etc. For example, the conductive layer 107 can be electrically connected to the heating electrode 106 through one or more via holes 112. When the electrical connection is achieved through multiple via holes 112, the connection resistance can be effectively reduced and the energy loss can be reduced. When the electrical connection is achieved through one via hole 112, the production process can be simplified.

[0082] The number of the conductive layer 107 may be one or more, and the embodiments of the present disclosure are not limited to this. When a plurality of conductive layers 107 are used to apply an electrical signal to the heating electrode 106, different parts of the heating electrode 106 can receive the electrical signal at the same time, so that each position of the heating electrode 106 flows through a current of substantially the same magnitude, so that the heat generation is more uniform. For example, when there are multiple conductive layers 107, the first insulating layer 110 may include multiple vias 112, each via 112 exposes a portion of the conductive layer 107, so that the heating electrode 106 is electrically connected to the multiple conductive layers 107 through the multiple vias 112. For example, the multiple conductive layers 107 correspond to the multiple vias 112 one by one. For another example, the number of the multiple vias 112 may also be greater than the number of the multiple conductive layers 107, and each conductive layer 107 is electrically connected to the heating electrode 106 through one or more vias 112.

[0083] It should be noted that in Figure 1 and Figure 2 In the example shown, the heating electrode 106 and the conductive layer 107 are located in different layers. In some other embodiments, the heating electrode 106 and the conductive layer 107 may also be located in the same layer. In this case, the first insulating layer 110 may be omitted in the array substrate 100, and the heating electrode 106 and the conductive layer 107 are electrically connected by overlapping.

[0084] The resistance value of the heating electrode 106 is greater than the resistance value of the conductive layer 107, so that under the action of the same electrical signal, the heating electrode 106 generates more heat to heat the recessed portion 103. The conductive layer 107 generates less heat, thereby reducing energy loss. For example, the conductive layer 107 can be made of a material with a lower resistivity, thereby reducing energy loss on the conductive layer 107. The conductive layer 107 can be made of a metal material, and the metal material can be, for example, copper or copper alloy, aluminum or aluminum alloy, etc., and can be a single metal layer or a composite metal layer, and the embodiments of the present disclosure are not limited to this.

[0085] In some embodiments of the present disclosure, the heating electrode 106 is made of indium tin oxide (ITO) or tin oxide, and the conductive layer 107 is made of a metal material. Since ITO is not easily oxidized, it can prevent the heating electrode 106 from being partially oxidized when exposed to the air, thereby avoiding problems such as uneven heating or increased power consumption caused by oxidation of the heating electrode 106. The conductive layer 107 is covered by the first insulating layer 110, so even if it is made of a metal material, it is not easy to be oxidized.

[0086] refer to Figure 5 , the vias 112 in the first insulating layer 110 include a first group of multiple vias 112a and a second group of multiple vias 112b. The first group of vias 112a and the second group of vias 112b are respectively located on opposite sides of the array substrate 100. The conductive layer 107 includes a first group of conductive layers 1071 and a second group of conductive layers 1072. The first group of conductive layers 1071 and the first group of vias 112a are located on the same side. The first group of conductive layers 1071 is electrically connected to the heating electrode 106 through the first group of vias 112a. The orthographic projection of the second group of conductive layers 1072 on the first substrate 101 falls on the periphery of the orthographic projection of the heating electrode 106 on the first substrate 101, and the second group of conductive layers 1072 at least partially surrounds the heating electrode 106. The second group of conductive layers 1072 is electrically connected to the heating electrode 106 through the second group of vias 112b. With such an arrangement, the conductive layer 107 can at least partially surround the heating electrode 106 , which can reduce heat loss of the heating electrode 106 , make the temperature of each recessed portion 103 more uniform, and improve the heating efficiency of the heating electrode 106 , thereby reducing power consumption.

[0087] In a conventional array substrate, a high voltage signal is usually applied to the heating electrode only through one conductive layer, and a low voltage signal (such as a ground voltage) is applied to the heating electrode through another conductive layer, so as to form a current path, such as along a first direction, on the heating electrode, so that the heating electrode generates heat. Since the heating electrode itself has a large resistance value, a large voltage drop will be generated in the direction extending from the connection between the heating electrode and the conductive layer along the second direction perpendicular to the first direction, so that the heating electrode can be divided into a first part of the electrode and a second part of the electrode distributed along the second direction. The voltage signal received by the first part of the electrode is large, and the first part of the electrode is, for example, the electrode part at the connection between the heating electrode and the conductive layer, and the voltage signal received by the second part of the electrode is small, and the second part of the electrode is, for example, the electrode part away from the above connection along the second direction. Correspondingly, the current in the heating electrode is not uniform, the current in the first part of the electrode is large and the heat generated is large, and the current in the second part of the electrode is small and the heat generated is small. Therefore, when such a heating electrode is used to heat the recessed portion in the array substrate, the temperature reached by the recessed portion at different positions is different, which ultimately affects the amplification reaction of the reaction system solution in the recessed portion and affects the accuracy of the detection effect.

[0088] In the embodiment of the present disclosure, the first group of multiple conductive layers 1071 (two are shown in the figure) apply a first voltage signal (for example, a high voltage signal) to the heating electrode 106 via the first group of vias 112a, and the second group of multiple conductive layers 1072 (two are shown in the figure) apply a second voltage signal (for example, a ground signal) to the heating electrode 106 via the second group of vias 112b to form a current path on the heating electrode 106. By arranging such multiple groups of conductive layers and making each group contain multiple conductive layers, and combining the previously described heating electrode 106 to be divided into multiple sub-parts separated from each other, one end of each sub-part of the heating electrode 106 (the end close to the first group of vias 112a) can be simultaneously applied with the same first voltage signal, and the other end of each sub-part of the heating electrode 106 (the end close to the second group of vias 112b) can be simultaneously applied with the same second voltage signal, thereby forming a uniform current in the heating electrode 106 and generating uniform heat, so that the recessed portion 103 at each position reaches a uniform temperature, promoting the amplification reaction of the reaction system solution in the recessed portion 103, and improving the accuracy of the detection effect.

[0089] In order to facilitate the conductive layer 107 to be electrically connected to an external device (not shown) independent of the array substrate 100 to receive an electrical signal (eg, a voltage signal), the array substrate 100 may further include a contact portion 113 (eg, Figure 5As shown, for example, the Pad area), the contact portion 113 is not covered by the first insulating layer 110. For example, the contact portion 113 is a relatively large square shape, so that it can be easily contacted and connected with a probe or electrode in an external device, and its contact area is large, and it can stably receive electrical signals. In this way, the array substrate 100 can be plug-and-play, simple to operate, and easy to use. For example, the contact portion 113 can be located in the same layer as the conductive layer 107 and formed by a single patterning process. When the conductive layer 107 is prepared using a metal material, the contact portion 113 can be electroplated, thermally sprayed, or vacuum-plated, so that a metal protective layer is formed on the surface of the contact portion 113 to prevent the contact portion 113 from oxidizing without affecting its conductive properties.

[0090] Continue to refer Figure 5 , the array substrate 100 includes a reaction area 1001 and a peripheral area 1002, and the peripheral area 1002 at least partially surrounds the reaction area 1001. In some embodiments, in the first direction X, the peripheral area 1002 includes a first sub-area 1002a and a second sub-area 1002b respectively located on both sides of the reaction area 1001. In other embodiments, the peripheral area 1002 completely surrounds the reaction area 1001, that is, the peripheral area 1002 is annular and surrounds the reaction area 1001. In this case, in the first direction X, the peripheral area 1002 includes a first sub-area 1002a and a second sub-area 1002b respectively located on both sides of the reaction area 1001, and in the second direction Y, the peripheral area 1002 also includes a third sub-area and a fourth sub-area respectively located on both sides of the reaction area 1001, the first sub-area 1002a is connected to both the third sub-area and the fourth sub-area, and the second sub-area 1002b is also connected to both the third sub-area and the fourth sub-area, so that the peripheral area 1002 surrounds the reaction area 1001.

[0091] like Figure 5 As shown, the via 112 is located in the peripheral region 1002, and the heating electrode 106 is at least partially located in the reaction region 1001. In some embodiments, the reaction region 1001 further includes a functional region 1001a, and the recessed portion 103 is located in the functional region 1001a. For example, the orthographic projection of the heating electrode 106 on the first substrate 101 completely covers the functional region 1001a of the reaction region 1001, that is, the functional region 1001a is located within the orthographic projection of the heating electrode 106 on the first substrate 101, thereby ensuring that the heating electrode 106 can heat each recessed portion 103.

[0092] It should be noted that when the peripheral region 1002 further includes a third sub-region and a fourth sub-region respectively located on both sides of the reaction region 1001 in the second direction Y, multiple conductive layers 107 may also be provided in the third sub-region and the fourth sub-region. The embodiments of the present disclosure do not limit the number, setting position, etc. of the conductive layers 107.

[0093] Return to continue reference Figure 1 and Figure 2 , the array substrate 100 may further include a hydrophilic layer 108, which covers at least the sidewall of each recessed portion 103. In some embodiments, the hydrophilic layer 108 covers the sidewall of each recessed portion 103. In an alternative embodiment, the hydrophilic layer 108 covers not only the sidewall of each recessed portion 103, but also the surface of the defining layer 102 away from the first substrate 101 and the bottom of each recessed portion 103. In an embodiment in which the recessed portion 103 penetrates the defining layer 102 (i.e., the recessed portion 103 is a through-hole structure), the hydrophilic layer 108 covers the sidewall of the recessed portion 103. In an embodiment in which the recessed portion 103 does not completely penetrate the defining layer 102 (i.e., the recessed portion 103 is a blind hole structure), the hydrophilic layer 108 covers the sidewall and bottom of the recessed portion 103. The hydrophilic layer 108 has hydrophilic and oleophobic properties. Since the sidewall (and bottom) of the recessed portion 103 is provided with a hydrophilic layer 108, the hydrophilicity of the recessed portion 103 is greatly improved, and the contact angle between the droplet in the reaction system solution and the surface of the recessed portion 103 is small. In the case where no driving force is applied to the reaction system solution from the outside, the reaction system solution can automatically and gradually enter each recessed portion 103 based on the capillary phenomenon, thereby realizing automatic injection and avoiding liquid cross-talk.

[0094] In some embodiments, the material of the hydrophilic layer 108 is silicon oxide, such as silicon dioxide (SiO 2 ) and the like. Of course, the embodiments of the present disclosure are not limited thereto, and the hydrophilic layer 108 may also be prepared using other suitable inorganic or organic materials, as long as the surface of the hydrophilic layer 108 away from the limiting layer 102 is hydrophilic. In some embodiments, the hydrophilic layer 108 may be directly prepared using a hydrophilic material. In other embodiments, the hydrophilic layer 108 may be prepared using a material that is not hydrophilic. In this case, it is necessary to perform a hydrophilic treatment on the surface of the hydrophilic layer 108 away from the limiting layer 102 so that the surface of the hydrophilic layer 108 away from the limiting layer 102 is hydrophilic. If a non-hydrophilic material (such as silicon nitride, etc.) is used to prepare the hydrophilic layer 108, the non-hydrophilic material may be hydrophilicized, for example, by using a gelation modification method, an ultraviolet radiation method, a plasma method, or the like, so that the surface of the non-hydrophilic material has a hydrophilic group and is thus hydrophilic.

[0095] like Figure 1 and Figure 2As shown, the array substrate 100 may further include a first hydrophobic layer 109 on a side of the hydrophilic layer 108 away from the first substrate 101, and a part of the hydrophilic layer 108 (i.e., the part of the covering and defining layer 102 of the hydrophilic layer 108 away from the surface of the first substrate 101) is located between the first hydrophobic layer 109 and the defining layer 102. The first hydrophobic layer 109 covers the surface of the hydrophilic layer 108 on the defining layer 102 away from the first substrate 101 and extends to the junction of this surface and the side wall of the recess 103, so that the first hydrophobic layer 109 defines a plurality of holes 114. In one example, the plurality of recesses 103 defined by the defining layer 102, the plurality of openings 105 defined by the shielding layer 104, and the plurality of holes 114 defined by the first hydrophobic layer 109 correspond one by one, and the first orthographic projection of each hole 114 on the first substrate 101 and the third orthographic projection of an opening 105 corresponding to the hole 114 on the first substrate 101 are both located within the second orthographic projection of a recess 103 corresponding to the hole 114 on the first substrate 101, and the first orthographic projection, the second orthographic projection, and the third orthographic projection form concentric circular rings, the first orthographic projection is located between the second orthographic projection and the third orthographic projection, and the third orthographic projection is located within the first orthographic projection, forming a concentric circular ring pattern as shown in Figure 5 the right figure. That is to say, the circular opening 105 defined by the shielding layer 104 has the smallest size, the circular recess 103 defined by the defining layer 102 has the largest size, and the circular hole 114 defined by the first hydrophobic layer 109 has a size between the two. Of course, the recesses 103, the openings 105, and the holes 114 are not limited to forming concentric circular rings, and they can also form, for example, concentric rectangular rings, concentric square rings, concentric elliptical rings, concentric polygonal rings, etc.

[0096] The first hydrophobic layer 109 has the characteristics of being hydrophobic and lipophilic. The material of the first hydrophobic layer 109 is resin or silicon nitride. For example, it can be an epoxy resin of the commercially available model DL-1001C. The first hydrophobic layer 109 can also be prepared using other suitable inorganic or organic materials, as long as the first hydrophobic layer 109 has hydrophobicity. In some embodiments, the first hydrophobic layer 109 can be directly prepared using a hydrophobic material. In other embodiments, the first hydrophobic layer 109 can be prepared using a material that does not have hydrophobicity. In this case, the surface of the first hydrophobic layer 109 needs to be hydrophobized so that the surface of the first hydrophobic layer 109 has hydrophobicity.

[0097] In the embodiment of the present disclosure, the hydrophilic layer 108 and the first hydrophobic layer 109 can jointly adjust the surface contact angle of the droplet of the reaction system solution, so that the microfluidic device including the array substrate 100 can realize self-imbibition liquid sampling and oil sealing. In the array substrate 100, the hydrophobic property of the outside of the recessed portion 103 is improved by setting the first hydrophobic layer 109, and the hydrophilic property of the inside of the recessed portion 103 (the side wall (and bottom) of the recessed portion 103) is improved by setting the hydrophilic layer 108, so as to facilitate the reaction system solution to infiltrate from the outside of the recessed portion 103 to the inside of the recessed portion 103. Therefore, under the joint action of the hydrophilic layer 108 and the first hydrophobic layer 109, the reaction system solution is more likely to enter each recessed portion 103.

[0098] In some embodiments, the ratio of the area of ​​the first hydrophobic layer 109 to the area of ​​the hydrophilic layer 108 is between 0.01 and 2.00. For example, the ratio of the area of ​​the first hydrophobic layer 109 to the area of ​​the hydrophilic layer 108 can be 0.01, 0.05, 0.10, 0.50, 1.00, 1.20, 1.40, 1.60, 1.80, 2.00, etc. If the area of ​​the first hydrophobic layer 109 is too large and the area of ​​the hydrophilic layer 108 is too small, the reaction system solution injected from the outside into the microfluidic device is easy to adhere to the surface of the first hydrophobic layer 109, and it is difficult to enter the recessed portion 103. In the embodiment of the present disclosure, by making the first hydrophobic layer 109 and the hydrophilic layer 108 have a suitable area ratio, under the joint action of the hydrophilic layer 108 and the first hydrophobic layer 109, the reaction system solution can more easily enter each recessed portion 103, thereby avoiding the waste of the reaction system solution and improving the utilization rate, thereby increasing the fluorescence emission intensity of the reagent to be detected in each recessed portion 103, and further improving the fluorescence detection accuracy of the reagent to be detected.

[0099] like Figure 1 and Figure 2 As shown, the array substrate 100 may further include a second insulating layer 111, which is located between the heating electrode 106 and the shielding layer 104. The second insulating layer 111 is used to protect the heating electrode 106, provide insulation, prevent liquid from corroding the heating electrode 106, slow down the aging of the heating electrode 106, and play a flattening role. In the case where the recessed portion 103 penetrates the limiting layer 102, the bottom of the recessed portion 103 exposes part of the surface of the second insulating layer 111, and the hydrophilic layer 108 covers the side wall of the recessed portion 103 and the exposed surface of the second insulating layer 111.

[0100] In some embodiments, the first insulating layer 110 and the second insulating layer 111 may be made of the same insulating material, such as an inorganic insulating material or an organic insulating material. In one example, the material of the first insulating layer 110 and the second insulating layer 111 includes silicon dioxide or silicon nitride.

[0101] It should be noted that, although the shielding layer 104 is shown in the figure as being located between the limiting layer 102 and the second insulating layer 111, this is only an example. As mentioned above, the shielding layer 104 may be located in any film layer between the first substrate 101 and the limiting layer 102 or at other locations as described later. For example, the shielding layer 104 may be located between the first substrate 101 and the conductive layer 107, between the conductive layer 107 and the first insulating layer 110, between the first insulating layer 110 and the heating electrode 106, between the heating electrode 106 and the second insulating layer 111, etc.

[0102] In the embodiments of the present disclosure, a shielding layer 104 having an opening 105 is provided so that the shielding layer 104 at least partially blocks the first substrate 101 and the limiting layer 102, thereby avoiding or at least reducing the background fluorescence interference caused by the limiting layer 102 and the first substrate 101, and improving the fluorescence detection accuracy of the reagent to be detected in the recess 103; by providing a heating electrode 106 having a plurality of separated sub-parts and optimizing the arrangement of the conductive layer 107, the temperature uniformity of the heating electrode 106 is improved, which is beneficial to the amplification reaction of the reaction system solution in the recess 103; by providing a hydrophilic layer 108 and a first hydrophobic layer 109, the reaction system solution can more easily enter each recess 103, thereby improving the reaction efficiency and avoiding liquid cross-talk.

[0103] Figure 7 FIG. 2 is a partial cross-sectional view of an array substrate 200 provided according to another embodiment of the present disclosure. As shown in the figure, in addition to the arrangement of the shielding layer 104 and the third insulating layer 115, the array substrate 200 and Figure 1 and Figure 2 The array substrate 100 shown is basically the same. The shielding layer 104 and the third insulating layer 115 in the array substrate 200 are described below. Other structures and corresponding technical effects can be referred to Figure 1 and Figure 2 The array substrate 100 shown is not described in detail here.

[0104] As shown in the figure, the shielding layer 104 is located on the side of the first substrate 101 away from the defining layer 102, that is, on the back side of the first substrate 101. The shielding layer 104 defines at least one opening 105, and the orthographic projection of the at least one opening 105 on the first substrate 101 at least partially overlaps with the orthographic projection of at least one recessed portion 103 on the first substrate 101, and the orthographic projection of the shielding layer 104 on the first substrate 101 at least partially overlaps with the orthographic projection of the defining layer 102 on the first substrate 101. It is worth noting that the figure only schematically shows one opening 105 defined by the shielding layer 104 and one recessed portion 103 defined by the defining layer 102, but as described above, the shielding layer 104 actually defines a plurality of openings 105, and the defining layer 102 defines a plurality of recessed portions 103, and each opening 105 corresponds to each recessed portion 103. In one example, the shape of the orthographic projection of each opening 105 on the first substrate 101 is circular, the shape of the orthographic projection of each recessed portion 103 on the first substrate 101 is also circular, and the diameter of the opening 105 is smaller than the diameter of the corresponding recessed portion 103. In the subsequent optical detection process, the excitation light can be incident into the recessed portion 103 from one side of the first substrate 101 through the opening 105 of the shielding layer 104. The shielding layer 104 is arranged on the side of the first substrate 101 away from the limiting layer 102. The arrangement of the shielding layer 104 is no longer limited by other film layers in the array substrate 200. The shielding layer 104 can occupy a larger area, which is conducive to the shielding layer 104 shielding a larger part of the first substrate 101 and the limiting layer 102 or completely shielding the first substrate 101 and the limiting layer 102, thereby further reducing or even avoiding the background fluorescence generated by the limiting layer 102 and the first substrate 101, and improving the fluorescence detection accuracy of the reagent to be detected in the recessed portion 103.

[0105] As shown in the figure, the array substrate 200 also includes a third insulating layer 115 located on the side of the shielding layer 104 away from the first substrate 101, and the third insulating layer 115 covers the shielding layer 104 to provide protection for the shielding layer 104 from the external environment. The figure shows that the third insulating layer 115 is a continuous film layer and completely fills the opening 105 of the shielding layer 104. In another example, the third insulating layer 115 is disconnected at the position corresponding to the opening 105, and a film layer of the same material as the third insulating layer 115 fills the opening 105 of the shielding layer 104. In another example, the third insulating layer 115 is also a continuous film layer, but does not fill the opening 105 of the shielding layer 104. The first insulating layer 110, the second insulating layer 111 and the third insulating layer 115 can be made of the same insulating material, for example, an inorganic insulating material or an organic insulating material. In one example, the materials of the first insulating layer 110, the second insulating layer 111 and the third insulating layer 115 include silicon dioxide or silicon nitride.

[0106] Figure 8 FIG. 1 is a partial cross-sectional view of an array substrate 300 provided according to another embodiment of the present disclosure. As shown in the figure, in addition to the arrangement of the shielding layer 104 and the hydrophilic layer 108, the array substrate 300 and Figure 1 and Figure 2 The array substrate 100 shown is basically the same. The shielding layer 104 and the hydrophilic layer 108 in the array substrate 300 are described below. Other structures and corresponding technical effects can be referred to Figure 1 and Figure 2 The array substrate 100 shown is not described in detail here.

[0107] As shown in the figure, the shielding layer 104 includes a first portion 104a, which is located on the side of the defining layer 102 away from the first substrate 101, and is attached to the side of the defining layer 102 and the surface away from the first substrate 101. It should be noted that the terms such as "A is attached to B" herein refer to the direct contact between the surfaces of A and B. Here, the first portion 104a of the shielding layer 104 is in direct contact with the side of the defining layer 102 and the surface away from the first substrate 101, and at least partially surrounds the defining layer 102. The first portion 104a of the shielding layer 104 defines a plurality of openings 105, and the orthographic projection of each opening 105 on the first substrate 101 at least partially overlaps with the orthographic projection of a corresponding recessed portion 103 on the first substrate 101. In one example, the orthographic projection of each opening 105 on the first substrate 101 is circular, and the orthographic projection of each recessed portion 103 on the first substrate 101 is also circular, and the diameter of the opening 105 is smaller than the diameter of the corresponding recessed portion 103. Through such an arrangement, in the subsequent optical detection process, the excitation light can be directly irradiated from the top of the array substrate 300 through the opening 105 of the shielding layer 104 to the reagent to be detected in the recessed portion 103 (i.e., from top to bottom in the figure), thereby improving the utilization rate of the light source and improving the fluorescence emission intensity of the reagent to be detected. The side surface of the limiting layer 102 and the surface away from the first substrate 101 are completely shielded by the first part 104a of the shielding layer 104, and therefore will not be irradiated by the excitation light.

[0108] Although the above embodiment is described as two independent film structures of the limiting layer 102 and the first part 104a of the shielding layer 104, as mentioned above, the limiting layer 102 and the first part 104a of the shielding layer 104 may also be the same film structure. In the embodiment where the limiting layer 102 and the first part 104a of the shielding layer 104 are the same film structure, for example, by physically or chemically treating the side surface of the limiting layer 102 and the surface (i.e., the upper surface) away from the first substrate 101 to make it opaque, the side surface and the upper surface of the limiting layer 102 serve as the first part 104a of the shielding layer 104; and the remaining untreated part of the limiting layer 102 continues to serve as the limiting layer 102.

[0109] The hydrophilic layer 108 is disposed on the surface of the first portion 104a of the shielding layer 104 away from the first substrate 101, and covers the surface of the first portion 104a of the shielding layer 104 and at least covers the sidewalls of each recessed portion 103. The hydrophilic layer 108 has hydrophilic and oleophobic properties. Since the hydrophilic layer 108 at least covers the sidewalls of the recessed portion 103, the hydrophilicity of the recessed portion 103 can be improved. In the absence of a driving force applied to the reaction system solution by the outside world, the reaction system solution can automatically and gradually enter each recessed portion 103 based on the capillary phenomenon, thereby realizing automatic injection and avoiding liquid cross-talk.

[0110] Figure 9 FIG. 4 is a partial cross-sectional view of an array substrate 400 provided according to another embodiment of the present disclosure. As shown in the figure, in addition to the arrangement of the shielding layer 104 and the hydrophilic layer 108, the array substrate 400 and Figure 1 and Figure 2 The array substrate 100 shown is basically the same. The shielding layer 104 and the hydrophilic layer 108 in the array substrate 400 are described below. Other structures and corresponding technical effects can be referred to Figure 1 and Figure 2 The array substrate 100 shown is not described in detail here.

[0111] As shown in the figure, the shielding layer 104 includes a first portion 104a and a second portion 104b. The first portion 104a is located on the side of the defining layer 102 away from the first substrate 101, and is attached to the side surface of the defining layer 102 and the surface away from the first substrate 101; the second portion 104b is located between the second insulating layer 111 and the defining layer 102, and is attached to the surface (i.e., the bottom surface) of the defining layer 102 close to the first substrate 101. The first portion 104a and the second portion 104b jointly surround the defining layer 102. The first portion 104a of the shielding layer 104 defines a plurality of openings 105, and the orthographic projection of each opening 105 on the first substrate 101 at least partially overlaps with the orthographic projection of a corresponding recessed portion 103 on the first substrate 101; the second portion 104b of the shielding layer 104 defines a plurality of openings 105, and the orthographic projection of each opening 105 on the first substrate 101 at least partially overlaps with the orthographic projection of a corresponding recessed portion 103 on the first substrate 101. Through such an arrangement, in the subsequent optical detection process, the excitation light can be directly irradiated from the top of the array substrate 300 through the opening 105 of the first part 104a of the shielding layer 104 to the reagent to be detected in the recessed portion 103 (i.e., from top to bottom in the figure), or from the bottom of the array substrate 300 through the opening 105 of the second part 104b of the shielding layer 104 to the recessed portion 103 (i.e., from bottom to top in the figure), so that the position of the light source emitting the excitation light can be flexibly arranged as needed. Since all surfaces (upper surface, lower surface, and each side surface) of the limiting layer 102 are completely shielded by the shielding layer 104, they will not be irradiated by the excitation light.

[0112] In one example, the orthographic projection of the opening 105 defined by the first portion 104a of the shielding layer 104 on the first substrate 101 completely overlaps with the orthographic projection of the opening 105 defined by the second portion 104b of the shielding layer 104 on the first substrate 101. For example, the orthographic projection of the opening 105 defined by the first portion 104a of the shielding layer 104 on the first substrate 101 is circular, and the orthographic projection of the opening 105 defined by the second portion 104b of the shielding layer 104 on the first substrate 101 is also circular, and the sizes of the openings defined by the first portion 104a and the second portion 104b are exactly the same. In another example, the shape of the orthographic projection of the recessed portion 103 on the first substrate 101 is a circle, the shape of the orthographic projection of the opening 105 defined by the first portion 104a of the shielding layer 104 on the first substrate 101 is a circle, and the shape of the orthographic projection of the opening 105 defined by the second portion 104b of the shielding layer 104 on the first substrate 101 is also a circle, and the sizes of the openings defined by the first portion 104a and the second portion 104b are exactly the same and are both smaller than the size of the recessed portion 103.

[0113] Although the above embodiment is described as the defining layer 102 and the first part 104a and the second part 104b of the shielding layer 104 being independent film structures, as mentioned above, the defining layer 102 and the first part 104a and the second part 104b of the shielding layer 104 may also be the same film structure. In the embodiment where the defining layer 102 and the first part 104a and the second part 104b of the shielding layer 104 are the same film structure, for example, by physically or chemically treating the side surface of the defining layer 102, the surface away from the first substrate 101 (i.e., the upper surface), and the surface close to the first substrate 101 (i.e., the lower surface) to make it opaque, the side surface, the upper surface, and the lower surface of the defining layer 102 (i.e., all the outer surfaces of the defining layer 102) serve as the first part 104a and the second part 104b of the shielding layer 104; and the remaining untreated part of the defining layer 102 (e.g., the inner part of the defining layer 102 wrapped by the outer surface) continues to serve as the defining layer 102.

[0114] The hydrophilic layer 108 is disposed on the surface of the first portion 104a of the shielding layer 104 away from the first substrate 101, and covers the surface of the first portion 104a of the shielding layer 104 and at least covers the sidewalls of each recessed portion 103. The hydrophilic layer 108 has hydrophilic and oleophobic properties. Since the hydrophilic layer 108 at least covers the sidewalls of the recessed portion 103, the hydrophilicity of the recessed portion 103 can be improved. In the absence of a driving force applied to the reaction system solution by the outside world, the reaction system solution can automatically and gradually enter each recessed portion 103 based on the capillary phenomenon, thereby realizing automatic injection and avoiding liquid cross-talk.

[0115] According to another aspect of the present disclosure, a microfluidic device is provided, the microfluidic device includes the array substrate described in any of the above embodiments, and the microfluidic device including the array substrate 100 is used as an example for description below. It should be noted that the array substrate provided herein can be used not only in the microfluidic field, but also in any other appropriate field, such as the display field, the automotive field, etc.

[0116] Figure 10 A microfluidic device 500 is shown, which includes an array substrate 100, an opposing substrate 2000 that is aligned with the array substrate 100, and a spacer between the array substrate 100 and the opposing substrate 2000. The opposing substrate 2000 includes a second substrate 201 and a second hydrophobic layer 202, and the second hydrophobic layer 202 is located on a side of the second substrate 201 close to the first substrate 101. The opposing substrate 2000 includes at least one through hole that penetrates the second substrate 201 and the second hydrophobic layer 202. In some embodiments, the size of the microfluidic device 500 is 1.5 cm*1.5 cm.

[0117] In one example, the first substrate 101 and the second substrate 201 are both glass substrates. The second substrate 201 is arranged opposite to the first substrate 101 to protect, support, isolate, etc. The microfluidic device 500 is prepared by micro-machining of glass substrate combined with semiconductor technology, so that large-scale batch production can be achieved, which can greatly reduce the corresponding production costs. It should be noted that in multiple embodiments of the present disclosure, the first substrate 101 and the second substrate 201 can also be made of other suitable materials, and the embodiments of the present disclosure are not limited to this.

[0118] In some embodiments, the shape of the first substrate 101 and the shape of the second substrate 201 are both rectangular. In some examples, the size of the first substrate 101 is 3.2 cm*4.5 cm, and the size of the second substrate 201 is 3.2 cm*3 cm. In some embodiments, the size of the second substrate 201 is smaller than the size of the first substrate 101, the second substrate 201 covers the reaction area 1001, and the orthographic projection of the second substrate 201 on the first substrate 101 can completely overlap with the reaction area 1001. It should be noted that the embodiments of the present disclosure are not limited to this. In some other examples, the size of the second substrate 201 can also be the same as the size of the first substrate 101. In this case, the second substrate 201 covers the reaction area 1001 and the peripheral area 1002. For example, the orthographic projection of the second substrate 201 on the first substrate 101 can completely overlap with the first substrate 101.

[0119] The second hydrophobic layer 202 has hydrophobic and oleophilic properties and is located on the side of the second substrate 201 facing the first substrate 101. By providing the second hydrophobic layer 202, the reaction system solution can more easily enter each recessed portion 103. In one example, the material of the second hydrophobic layer 202 includes SiN x In an alternative example, the second hydrophobic layer 202 is a light absorbing layer, and the material of the light absorbing layer includes TiO 2 By designing the second hydrophobic layer 202 as a light absorbing layer, some unused excitation light can be further absorbed to prevent the excitation light from irradiating the first substrate 101 and / or the defining layer 102 in some way, thereby further reducing the fluorescence interference of the first substrate 101 and / or the defining layer 102.

[0120] The counter substrate 2000 includes at least one through hole penetrating the second substrate 201 and the second hydrophobic layer 202. As shown in the figure, the counter substrate 2000 includes an injection hole 203 and an outlet hole 205, and the injection hole 203 and the outlet hole 205 both penetrate the second substrate 201 and the second hydrophobic layer 202. In one example, the reaction system solution can be injected into the injection hole 203 by a microinjection pump or a pipette, and then enter each recessed portion 103 by self-sucking. In some embodiments, combined with Figure 5 , the reaction area 1001 also includes a non-functional area 1001b, the injection hole 203 and the outlet hole 205 are both located in the non-functional area 1001b, and are located on different sides of the functional area 1001a, for example, symmetrically distributed on different sides of the functional area 1001a. Figure 5 As shown, in the first direction X, the injection hole 203 and the outlet hole 205 are respectively located on both sides of the functional area 1001a. For example, the injection hole 203 and the outlet hole 205 are symmetrically distributed about the second direction Y, so that the reaction system solution can flow more evenly in the microfluidic device 500, which facilitates the reaction system solution to enter each recessed portion 103. Of course, the embodiments of the present disclosure are not limited to this, and the injection hole 203 and the outlet hole 205 can also be symmetrically distributed about the first direction X or other arbitrary directions. It should be noted that the injection hole 203 and the outlet hole 205 can also be located in the functional area 1001a.

[0121] Continue to refer Figure 10 , the microfluidic device 500 also includes a plurality of sealants 204. The plurality of sealants 204 are arranged in the peripheral area 1002 and are located between the array substrate 100 and the opposing substrate 2000. The plurality of sealants 204 are configured to maintain the interval between the array substrate 100 and the opposing substrate 2000, thereby providing space for the flow of the reaction system solution. In some embodiments, a portion of the sealants 204 may also be arranged in the reaction area 1001, for example, dispersedly arranged in multiple locations of the reaction area 1001, thereby improving the compressive strength of the microfluidic device 500 and preventing the reaction area 1001 from being damaged by external forces and causing the microfluidic device 500. In some embodiments, the sizes and shapes of the plurality of sealants 204 may be the same as each other, thereby improving the thickness uniformity of the microfluidic device 500. In an alternative embodiment, the sizes and shapes of the plurality of frame sealants 204 may also be set according to possible stress conditions of the microfluidic device 500 . For example, the size of the frame sealants 204 may be larger at the periphery and center of the microfluidic device 500 , and smaller at other locations.

[0122] In some embodiments, in a direction perpendicular to the first substrate 101, the height of the sealant 204 is greater than the height of the limiting layer 102, and the first substrate 101, the limiting layer 102, and the sealant 204 jointly define the inlet and outlet channels of the reaction system solution, thereby ensuring that the reaction system solution can move to each recessed portion 103, and allowing the reaction system solution that has not entered the recessed portion 103 to flow out of the space between the array substrate 100 and the counter substrate 2000. In some embodiments, the height of the sealant 204 is 30% or 50% greater than the height of the limiting layer 102, and the specific ratio between the two can be determined, for example, according to actual needs, and the embodiments of the present disclosure are not limited thereto.

[0123] The material of the sealant 204 may be a curable organic material, such as a thermosetting material or a light-curing material, for example, an ultraviolet (UV) curable acrylic resin or other suitable material. The shape of the sealant 204 may be spherical. At this time, the array substrate 100 and the opposing substrate 2000 may be cured and packaged by the sealant 204 so that the array substrate 100 and the opposing substrate 2000 are aligned. In this way, the sealant 204 may control the spacing between the array substrate 100 and the opposing substrate 2000. The embodiments of the present disclosure include but are not limited to this, and the shape of the sealant 204 may also be any applicable shape such as a columnar shape or an ellipsoidal shape.

[0124] In some embodiments, the microfluidic device 500 may further include a first temperature sensor (not shown in the figure). The first temperature sensor is disposed on a side of the first substrate 101 away from the second substrate 201 and located in the reaction area 1001. The first temperature sensor is configured to detect the temperature of the reaction area 1001. For example, the temperature at the reaction area 1001 needs to be maintained at a predetermined temperature (e.g., 95°C, 55°C, or 72°C, etc.). At this time, the first temperature sensor can detect the temperature at the reaction area 1001 in real time, and then adjust the temperature at the reaction area 1001 in real time through the heating electrode 106, so that the temperature of the reaction area 1001 is maintained at a predetermined temperature, thereby preventing the temperature of the reaction area 1001 from being too high or too low to affect the amplification reaction. The first temperature sensor can be various types of temperature sensors, including but not limited to contact temperature sensors or non-contact temperature sensors, such as thermocouple temperature sensors or infrared temperature sensors.

[0125] The microfluidic device 500 provided in the embodiment of the present disclosure can have substantially the same technical effects as the array substrate described in the previous embodiments. Therefore, for the purpose of brevity, a repeated description will not be given here.

[0126] According to another aspect of the present disclosure, a microfluidic system is provided, which includes a control device and a microfluidic device 500 described in any of the previous embodiments. The control device is electrically connected to the microfluidic device 500 and is configured to control the temperature of the microfluidic device 500. The microfluidic system helps to automatically allow droplets to enter each recessed portion 103 of the microfluidic device 500, can achieve effective sample injection and avoid cross-liquid, can effectively achieve temperature control of the recessed portion 103 of the microfluidic device 500, can achieve temperature cycling without driving the droplets, and does not require external heating equipment, and has high integration, simple operation, and low production cost.

[0127] Figure 11 FIG. 6 is a schematic block diagram of a microfluidic system 600 provided according to an embodiment of the present disclosure. Figure 11 As shown, the microfluidic system 600 includes a microfluidic device 500, a control device 620, and a power supply device 630, which provides a signal voltage or a driving voltage to the microfluidic device 500 and the control device 620. The control device 620 is electrically connected to the microfluidic device 500 and is configured to apply an electrical signal to the microfluidic device 500 to drive the heating electrode 106 of the microfluidic device 500. The multiple recessed portions 103 of the microfluidic device 500 can accommodate a reaction system solution. The control device 620 applies an electrical signal to the heating electrode 106 of the microfluidic device 500, so that the heating electrode 106 releases heat, thereby controlling the temperature of the functional area of ​​the microfluidic device 500, so that the reaction system solution performs an amplification reaction. For example, the control device 620 can be implemented as general or dedicated hardware, software or firmware, etc., for example, it can also include a central processing unit (CPU), an embedded processor, a programmable logic controller (PLC), etc., and the embodiments of the present disclosure are not limited to this.

[0128] In some embodiments, the microfluidic system 600 may optionally further include a second temperature sensor 650. For example, when the microfluidic device 500 does not include the first temperature sensor, it is necessary to set the second temperature sensor 650 in the microfluidic system 600, and the second temperature sensor 650 needs to be set at a position substantially the same as the first temperature sensor in the microfluidic device 500, so as to realize the function of detecting temperature. For example, the second temperature sensor 650 is set on the side of the first substrate 101 of the microfluidic device 500 away from the second substrate 201, and is located in the reaction area 1001 of the array substrate 100, and the second temperature sensor 650 is configured to detect the temperature of the reaction area 1001 of the microfluidic device 500. The second temperature sensor 650 can be various types of temperature sensors, including but not limited to contact temperature sensors or non-contact temperature sensors, such as thermocouple temperature sensors or infrared temperature sensors. It should be noted that in some other embodiments, when the microfluidic device 500 includes the first temperature sensor, the microfluidic system 600 including the microfluidic device 500 does not need to be provided with the second temperature sensor 650.

[0129] The microfluidic system 600 may further include an optical unit 640, which is configured to perform optical detection on the microfluidic device 500. In some embodiments, the optical unit 640 includes a fluorescence detection device, which is configured to perform fluorescence detection on the reagent to be detected in the plurality of recesses 103. For example, the fluorescence detection device may include a fluorescence light source and an image sensor (e.g., a charge coupled device (CCD) image sensor). The optical unit 640 may further include an image processing device, which is configured to process the detection image output by the fluorescence detection device. For example, the image processing device may include a central processing unit (CPU) or a graphics processing unit (GPU), etc. For example, the control device 620 is also configured to control the fluorescence detection device and the image processing device to perform corresponding functions.

[0130] The working principle and process of the microfluidic system 600 are described as follows.

[0131] First, configure the reaction system solution. For example, the reaction system solution may include a cell lysate, a DNA fragment sample solution after being broken by a DNA lysing enzyme, and a PCR amplification reagent. In one example, assuming that the DNA to be detected is exon 19 of the epidermal growth factor receptor (EGFR) gene, the PCR amplification reagent accordingly contains a PCR amplification primer specific for exon 19 of the EGFR gene. For example, the volume of the reaction system solution is 20 microliters, and the reaction system solution includes 10 microliters of MIX reagent (MIX reagent includes Taq enzyme, dNPTs and MgCl2), 0.6 microliters of upstream primer (10 millimoles (mM)), 0.6 microliters of downstream primer (10mM), 7.8 microliters of water, and 1 microliter of fully diluted template deoxyribonucleic acid (DNA) to ensure that the number of template DNA in each micro-reaction chamber is less than or equal to 1.

[0132] Then, a polytetrafluoroethylene connector and a silicone tube are installed on the injection hole 203 of the microfluidic device 500, and the above-configured reaction system solution is injected into the injection hole 203 through a microinjection pump or a pipette. The reaction system solution enters the injection hole 203 through the polytetrafluoroethylene connector and the silicone tube, and then the reaction system solution enters each recessed portion 103 through self-imbibition under the mutual cooperation of the hydrophilic layer 108 and the first hydrophobic layer 109.

[0133] Next, a three-step dPCR is used for the thermal cycle amplification process. The oil-sealed microfluidic device 500 is placed on the chip carrier of the microfluidic system 600 and fixed by a clamp so that the electrode and the conductive layer 107 of the microfluidic device 500 are electrically connected. The parameters are set by, for example, the parameter setting button, and the cycle parameters are 95°C denaturation for 15 seconds, 55°C annealing for 45 seconds, and 72°C extension for 45 seconds, with a total of 30 thermal cycles. For example, a pre-denaturation at 95°C can also be set for 5 minutes. The droplets in the microreaction chamber containing the template DNA in the microfluidic device 500 will undergo a PCR amplification reaction, while the droplets in the microreaction chamber without the template DNA will serve as a control group.

[0134] It should be noted that before PCR amplification, the recessed portion 103 can be filled with a bovine serum albumin (BSA) solution with a mass fraction of 0.2% and soaked for 1 hour to reduce the adsorption of PCR reagents and sample templates on the inner surface of the recessed portion 103, thereby improving the reaction efficiency and detection accuracy. Then, the BSA solution is extracted cleanly using a micropump, and the reaction system solution is injected into the recessed portion 103, and then sealed with an oil phase liquid. The oil phase liquid seal can use mineral oil, liquid paraffin, isopropyl palmitate, butyl laurate, perfluoroalkane oil, etc. to seal the injection hole 203 and the sample outlet hole 205 to prevent the reaction system solution from volatilizing.

[0135] After 30 cycles of amplification, the reaction system solution in the recessed portion 103 becomes a reagent to be detected after polymerase chain reaction. The microfluidic device 500 is taken out and observed by a fluorescence microscope. The excitation wavelength can be, for example, 450nm~480nm, so as to obtain a fluorescence spectrum. In one example, when the reagent to be detected contains the 19th exon of the EGFR gene mutation, since the reagent to be detected includes the specific PCR amplification primer of the 19th exon of the EGFR gene mutation, the mutated exon 19 is greatly amplified under the action of the PCR amplification primer, so that the reagent to be detected presents a positive result, that is, at least part of the reagent to be detected undergoes a fluorescent reaction. In another example, when the reagent to be detected does not contain the 19th exon of the EGFR gene mutation, the reagent to be detected presents a negative result, that is, the reagent to be detected does not undergo a fluorescent reaction. Thus, the detection of the 19th exon of the EGFR gene can be achieved.

[0136] The microfluidic system 600 provided in the embodiment of the present disclosure can have substantially the same technical effects as the array substrate described in the previous embodiments. Therefore, for the purpose of brevity, a repeated description will not be given here.

[0137] According to yet another aspect of the present disclosure, a fluorescence detection method is provided. Figure 12 FIG. 7 shows a flow chart of a fluorescence detection method 700 provided according to an embodiment of the present disclosure. Figure 13 FIG. 5 is a schematic diagram showing a fluorescence detection process of a microfluidic device 500 according to an embodiment of the present disclosure. Figure 12 and Figure 13 The fluorescence detection method 700 is described.

[0138] S701: Accommodate a reagent to be detected in at least one recess of a microfluidic device.

[0139] In one example, the prepared reaction system solution is injected into the injection hole 203 of the microfluidic device 500, and the reaction system solution enters each recess 103 of the microfluidic device 500 through self-imbibition under the cooperation of the hydrophilic layer 108 and the first hydrophobic layer 109. After the reaction system solution in each recess 103 undergoes polymerase chain reaction, that is, after the amplification reaction is completed, the above-mentioned reagent to be detected is formed.

[0140] S702: Allow light of a first wavelength emitted by a light source to irradiate at least one recessed portion through at least one opening of the shielding layer.

[0141] like Figure 13As shown, the fluorescence detection device 300 includes a light source system (not shown), which emits light 301 of a first wavelength. The light 301 of the first wavelength is irradiated into the corresponding multiple recesses 103 defined by the limiting layer 102 through the multiple openings 105 of the shielding layer 104, thereby stimulating the reagent to be detected in each recess 103 to emit fluorescence. The light 301 of the first wavelength shown in the figure is incident from bottom to top, because the shielding layer 104 is located below the limiting layer 102. When the shielding layer 104 is located above the limiting layer 102 (such as Figure 8 and Figure 9 As shown in FIG. 3 ), the light 301 of the first wavelength may also be incident from top to bottom. In addition, it should be noted that the light source system may be integrated into the fluorescence detection device 300 or may be independent of the fluorescence detection device 300, and the embodiments of the present disclosure are not limited thereto.

[0142] S703: Detect the light of the second wavelength emitted by the reagent to be detected.

[0143] In one example, after the reagent to be detected in the recessed portion 103 is excited by the light 301 of the first wavelength, it emits the light 302 of the second wavelength, which is greater than the first wavelength. For example, the light 301 of the first wavelength can be blue light, and the light 302 of the second wavelength can be green light; or, the light 301 of the first wavelength can be yellow light, and the light 302 of the second wavelength can be red light. The fluorescence detection device 300 can, for example, include a fluorescence light source and an image sensor (such as a charge coupled device (CCD) image sensor). The image processing device is configured to process the detection image output by the fluorescence detection device 300. For example, the image processing device can include a central processing unit (CPU) or a graphics processing unit (GPU), etc.

[0144] Figure 14A The fluorescence image of the microfluidic device without a shielding layer in conventional technology is shown. Figure 14B A fluorescent image of a microfluidic device 500 provided according to an embodiment of the present disclosure is shown. Figure 14A Each dot in FIG. 1 represents a recessed portion 103' of the microfluidic device. Figure 14A It can be seen that each recessed portion 103' and the surrounding area presents basically the same color. This is because there is no shielding layer in the conventional microfluidic device. When the excitation light irradiates the recessed portion, not only the reagent to be detected in the recessed portion is excited to emit fluorescence, but also the substrate and the limiting layer in the microfluidic device are excited to emit fluorescence. Compared with the usually trace volume of the reagent to be detected, the background fluorescence caused by the substrate and the limiting layer in the microfluidic device greatly affects the fluorescence detection accuracy of the reagent to be detected in the recessed portion, making it impossible to obtain accurate detection results. Therefore, it is presented as Figure 14A The phenomenon shown is that almost the entire area emits fluorescence.

[0145] Figure 14B Each dot in FIG. 1 represents a recessed portion 103 of the microfluidic device 500 provided according to an embodiment of the present disclosure. Figure 14B It can be seen that the colors presented by each recessed portion 103 and the colors presented by its surrounding area are very different, and the contrast is very obvious. Each recessed portion 103 presents a relatively bright color, while the surrounding area is black. This is because a shielding layer 104 is provided in the microfluidic device 500, and the orthographic projection of the shielding layer 104 on the first substrate 101 overlaps at least partially with the orthographic projection of the limiting layer 102 on the first substrate 101, that is, the shielding layer 104 blocks at least a part or all of the limiting layer 102, and the orthographic projection of the shielding layer 104 on the first substrate 101 must also overlap at least partially with the first substrate 101 itself. When the light 301 of the first wavelength is irradiated to the recessed portion 103 via the opening 105 of the shielding layer 104, the shielding layer 104 can shield the first substrate 101 and the limiting layer 102. Therefore, the shielding layer 104 can not only prevent the limiting layer 102 from being irradiated by the light 301 of the first wavelength, but also prevent the fluorescence emitted by the first substrate 101 irradiated by the light 301 of the first wavelength from transmitting through the shielding layer 104. Therefore, the light 301 of the first wavelength can only irradiate the recessed portion 103 through the opening 105, and excite the reagent to be detected in the recessed portion 103 to emit fluorescence, thereby Figure 14B The position corresponding to the recessed portion 103 in the image is brighter in color, while the area other than the recessed portion 103 is black. Therefore, by such a fluorescence detection method, the fluorescence interference caused by the first substrate 101 and the limiting layer 102 can be reduced or even avoided, so that the fluorescence signal emitted by the reagent to be detected in the recessed portion 103 can be accurately identified by the detector, so that the reaction signal can be read more sensitively and accurately, the fluorescence detection accuracy of the reagent to be detected can be improved, and image data support can be provided for the data analysis of the subsequent nucleic acid amplification reaction. In addition, by such a detection method, clearer microwell array imaging can be achieved, the detection error caused by false positives can be reduced, and the interference between different channels in the multi-channel fluorescence signal detection process can be well avoided.

[0146] Another aspect of the present disclosure provides a method 800 for manufacturing a microfluidic device 500, which may include an array substrate described in any of the above embodiments. The following takes the microfluidic device 500 including the array substrate 100 as an example to briefly describe the method steps.

[0147] Step 801: Provide a first substrate 101. The first substrate 101 may be made of any suitable material. In one example, the first substrate 101 is made of glass.

[0148] Step 802: Form a conductive film layer on the first substrate 101 at about 240° C. In one example, a molybdenum (Mo) layer with a thickness of 200Å, an aluminum neodymium (AlNd) layer with a thickness of 3000Å, and a molybdenum (Mo) layer with a thickness of 800Å are sequentially deposited on the first substrate 101 to form the conductive film layer. The conductive film layer is patterned, such as by exposure, development, etching, etc., to form a conductive layer 107.

[0149] Step 803: Deposit a first insulating film layer on the conductive layer 107 at about 200° C., and pattern the first insulating film layer to form a first insulating layer 110 covering the conductive layer 107. In one example, the first insulating layer 110 is SiO with a thickness of about 3000 Å. 2 layer.

[0150] Step 804: patterning the first insulating layer 110 to form at least one via hole 112 penetrating the first insulating layer 110, wherein the at least one via hole 112 exposes a portion of the conductive layer 107. In one example, the first insulating layer 110 is etched in a dry etching machine to form the via hole 112. The specific process is described as follows: at a pressure of about 150 mtorr, a power of about 800 W, and a 2 The etching was performed for 10 s at a volume flow rate of about 400 sccm (standard cubic centimeter per minute); the etching was performed for 10 s at a pressure of about 60 mtorr, a power of about 800 W, and a CF 4 and O 2 The etching was performed for 200 s under the conditions of a gas volume flow ratio of about 200:50; the etching was performed for 200 s under the conditions of a pressure of about 130 mtorr, a power of about 800 W, and O 2 and CF 4 The etching was performed for 30 s at a gas volume flow ratio of about 400:40; and at a pressure of about 60 mtorr, a power of about 800 W, and a CF 4 and O 2 The etching was performed for 160 s under the condition that the gas volume flow ratio was about 200:50.

[0151] Step 805: depositing a conductive film layer on the side of the first insulating layer 110 away from the first substrate 101, and then performing processes such as exposure, development, etching, and stripping on the conductive film layer to form a patterned heating electrode 106. In one example, the material of the heating electrode 106 is ITO. In one example, the heating electrode 106 includes a plurality of sub-parts separated from each other.

[0152] Step 806: Deposit a second insulating film layer on the side of the heating electrode 106 away from the first substrate 101, and pattern the second insulating film layer to form a second insulating layer 111 that at least partially covers the heating electrode 106. In one example, the material of the second insulating layer 111 is SiO 2 In another example, the second insulating layer 111 includes SiO2 having a thickness of about 1000Å and a stacked 2 layer and SiN with a thickness of about 2000Å x layer.

[0153] Step 807: Coat a shielding film layer on the side of the second insulating layer 111 away from the first substrate 101, and pattern the shielding film layer to form a shielding layer 104 defining an opening 105. In one example, the specific steps of forming the shielding layer 104 may include: spin coating the shielding film layer on the side of the second insulating layer 111 away from the first substrate 101 at a pressure of 30 Kpa, with a spin coating speed of about 380 rpm and a spin coating time of about 7 seconds. Then pre-cure the spin-coated shielding film layer at 90°C for 120 seconds. Next, expose, develop, and etch the shielding film layer through a mask template, and the development time is about 75 seconds. Finally, post-cure the etched shielding film layer at 230°C for about 20 minutes to form a shielding layer 104 defining an opening 105. The thickness of the shielding layer 104 is, for example, in the range of 0.6-2.4 microns, for example, 2 microns. In one example, the material forming the shielding layer 104 includes chromium, chromium oxide, and black resin.

[0154] Step 808: Coat a limiting film layer on the side of the shielding layer 104 away from the first substrate 101, and pattern the limiting film layer to form a limiting layer 102 defining a plurality of recessed portions 103. In one example, the process of forming the limiting layer 102 is described as follows: First, under a pressure of 30Kpa, spin-coat an optical adhesive at a speed of 300 rpm on the surface of the shielding layer 104 away from the first substrate 101, and the spin-coating time is about 10 seconds, and then the optical adhesive is cured for 120 seconds at a temperature of 90°C. Repeat the above process twice to obtain a limiting film layer. Next, the limiting film layer is exposed through a mask, and then the exposed limiting film layer is developed with a developer for 100 seconds, and then etched. At a temperature of 230°C, the etched limiting film layer is cured for 30 minutes, and finally a limiting layer 102 defining a plurality of recessed portions 103 is obtained. The material of the limiting layer 102 includes photoresist. The orthographic projection of each opening 105 of the shielding layer 104 on the first substrate 101 at least partially overlaps with the orthographic projection of a corresponding recessed portion 103 of the defining layer 102 on the first substrate 101, and the orthographic projection of the shielding layer 104 on the first substrate 101 at least partially overlaps with the orthographic projection of the defining layer 102 on the first substrate 101. In one example, the recessed portion 103 of the defining layer 102 is a cylinder, the bottom diameter of the recessed portion 103 is 50 microns, the depth is between 40 and 50 microns, and the distance between the centers of two adjacent recessed portions 103 is 100 microns.

[0155] Step 809: At 200°C, deposit an insulating film layer on the surface of the limiting layer 102 away from the first substrate 101, and expose, develop, and etch the insulating film layer to form a patterned layer. Treat the patterned layer with a 0.4% KOH solution for about 15 minutes to hydrophilically modify the patterned layer, thereby forming a hydrophilic layer 108. The hydrophilic layer 108 covers the surface of the limiting layer 102 away from the first substrate 101, and at least covers the sidewalls of each recessed portion 103. In one example, the hydrophilic layer 108 is SiO with a thickness of about 3000Å. 2 layer.

[0156] Step 810: deposit an insulating film layer on the surface of the hydrophilic layer 108 away from the first substrate 101, and expose, develop, and etch the insulating film layer to form a first hydrophobic layer 109. In one example, the process of forming the first hydrophobic layer 109 is as follows: in a plasma enhanced chemical vapor deposition (PECVD) device, at a temperature of about 200°C, a power of about 600 W, a pressure of about 1200 mtorr, and a distance between the plasma reaction enhancement target in the PECVD device and the sample to be deposited of about 1000 mils, SiH is introduced into the reaction chamber.4 (volume flow rate is 110sccm), NH 3 (volume flow rate is 700 sccm) and N 2 (volume flow rate is 2260 sccm, flow time is 100 seconds) to deposit a SiN layer with a thickness of 1000Å on the surface of the hydrophilic layer 108 away from the first substrate 101. x The SiN x The film layer is exposed, developed, and etched to form a first hydrophobic layer 109 .

[0157] Step 811: packaging the array substrate 100 after the hydrophilic-hydrophobic treatment.

[0158] Step 812: Provide a second substrate 201. The second substrate 201 may be made of any suitable material. In one example, the second substrate 201 is made of glass.

[0159] Step 813: deposit a film layer on a side of the second substrate 201 close to the first substrate 101, and process the film layer to form a second hydrophobic layer 202. The second hydrophobic layer 202 is a TiO 2 In one example, the second hydrophobic layer 202 is made of a light absorbing material, which includes TiO 2 In another example, the second hydrophobic layer 202 is made of SiN x The second substrate 201 and the second hydrophobic layer 202 constitute an opposing substrate 2000 opposing the array substrate 100 .

[0160] Step 814: Punch the second substrate 201 and the second hydrophobic layer 202 to form at least one injection hole 203 and at least one output hole 205 that penetrate the second substrate 201 and the second hydrophobic layer 202. In one example, the diameter of the at least one injection hole 203 and the at least one output hole 205 is between 0.6 mm and 1.2 mm.

[0161] Step 815 : using a sealing adhesive to cure and package the array substrate 100 and the counter substrate 2000 , and defining a gap between the array substrate 100 and the counter substrate 2000 .

[0162] It should be noted that the manufacturing method may further include more steps, which may be determined according to actual needs, and the embodiments of the present disclosure do not limit this. The technical effects achieved by the manufacturing method can refer to the above description of the array substrate 100 and the microfluidic device 500, which will not be repeated here.

[0163] When the microfluidic device 500 includes Figure 7When the array substrate 200 is shown, the manufacturing method of the microfluidic device 500 is basically the same as the above method 800, except that the order of the steps is slightly different. According to the above steps 801-806 and steps 808-811, the first substrate 101, the conductive layer 107, the first insulating layer 110, the heating electrode 106, the second insulating layer 111, the limiting layer 102 and the recessed portion 103, the hydrophilic layer 108, the first hydrophobic layer 109 and the package are prepared in sequence, that is, step 807 is omitted (that is, the preparation step of the shielding layer 104 is omitted). After the package is completed, the array substrate formed with the above-mentioned film layers is turned over, and a shielding film layer is coated on the side of the first substrate 101 away from the limiting layer 102, and the shielding film layer is patterned to form a shielding layer 104 defining an opening 105. In one example, the specific steps of forming the shielding layer 104 may include: under a pressure of 30 Kpa, spin-coating a shielding film layer on a side of the second insulating layer 111 away from the first substrate 101, the spin-coating speed is about 380 rpm, and the spin-coating time is about 7 seconds. Then, the shielding film layer after spin coating is pre-cured at 90° C. for 120 seconds. Next, the shielding film layer is exposed, developed, and etched through a mask template, and the development time is about 75 seconds. Finally, the etched shielding film layer is post-cured for about 20 minutes at 230° C. to form a shielding layer 104 with openings 105 defined. The orthographic projection of each opening 105 of the shielding layer 104 on the first substrate 101 overlaps at least partially with the orthographic projection of a corresponding recessed portion 103 of the defining layer 102 on the first substrate 101, and the orthographic projection of the shielding layer 104 on the first substrate 101 overlaps at least partially with the orthographic projection of the defining layer 102 on the first substrate 101. The thickness of the shielding layer 104 is, for example, in the range of 0.6-2.4 micrometers, for example, 2 micrometers. In one example, the material forming the shielding layer 104 includes chromium, chromium oxide, and black resin.

[0164] Then, at about 200° C., a third insulating film layer is deposited on the side of the shielding layer 104 away from the first substrate 101, and the third insulating film layer is patterned to form a third insulating layer 115. The third insulating layer 115 has a protective effect on the shielding layer 104. In one example, the third insulating layer 115 is SiO with a thickness of about 3000 Å. 2 .

[0165] Finally, the counter substrate 2000 is prepared according to the above steps 812 - 815 , and the array substrate 200 and the counter substrate 2000 are cured and packaged, thereby completing the preparation of the microfluidic device 500 including the array substrate 200 .

[0166] When the microfluidic device 500 includes Figure 8When the array substrate 300 is shown, the manufacturing method of the microfluidic device 500 is basically the same as the above method 800, except that the order of step 807 and step 808 is exchanged. That is, after the first substrate 101, the conductive layer 107, the first insulating layer 110, the heating electrode 106, and the second insulating layer 111 are prepared in sequence according to the above steps 801-806, then according to step 808, a limiting layer 102 with multiple recesses 103 is prepared on the surface of the second insulating layer 111 away from the first substrate 107. Then, a shielding layer 104 with openings 105 is prepared on the surface of the limiting layer 102 away from the first substrate 101, and the preparation process is the same as described in the above step 807. The formed shielding layer 104 covers the side surface of the limiting layer 102 and the surface away from the first substrate 101. Finally, the subsequent preparation is continued according to steps 809-815 to complete the preparation of the microfluidic device 500 including the array substrate 300.

[0167] When the microfluidic device 500 includes Figure 9 When the array substrate 400 is shown, the manufacturing method of the microfluidic device 500 is basically the same as the above method 800, except that an additional step is added between step 808 and step 809. That is, the first substrate 101, the conductive layer 107, the first insulating layer 110, the heating electrode 106, the second insulating layer 111, the shielding layer 104 and the limiting layer 102 are prepared in sequence according to the above steps 801-808. In step 808, an exemplary process for preparing the limiting layer 102 is as follows: first, under a pressure of 30Kpa, the optical glue is spin-coated at a speed of 200 rpm on the surface of the shielding layer 104 away from the first substrate 101, and the spin-coating time is about 10 seconds, and then the optical glue is cured at a temperature of 90°C for 120 seconds. Next, the optical glue is exposed through a mask, and then the exposed optical glue is developed with a developer for 240 seconds, and then etched. The etched optical adhesive was cured at a temperature of 230° C. for 30 minutes, and finally a defining layer 102 defining a plurality of recessed portions 103 was obtained. The material of the defining layer 102 includes photoresist.

[0168] After the definition layer 102 is prepared, a shielding layer 104 with openings 105 is prepared again on the surface of the definition layer 102 away from the first substrate 101, and the preparation method is the same as described in the above step 807. The formed shielding layer 104 covers the side of the definition layer 102 and the surface away from the first substrate 101. Finally, the subsequent preparation is continued according to steps 809-815 to complete the preparation of the microfluidic device 500 including the array substrate 400. That is, when preparing the microfluidic device 500 including the array substrate 400, it is necessary to prepare the shielding layer 104 twice before and after the process of preparing the definition layer 102.

[0169] Another aspect of the present disclosure provides a method 900 for using the microfluidic device 500. The method 900 may include the following steps:

[0170] Step 901: allowing a reaction system solution to enter the plurality of recesses 103 of the microfluidic device 500 through the injection hole 203 of the microfluidic device 500;

[0171] Step 902 : applying an electrical signal to the conductive layer 107 of the microfluidic device 500 to drive the heating electrode 106 to heat the plurality of recesses 103 through the conductive layer 107 .

[0172] In some embodiments, the method 900 further includes: cooling the plurality of recesses 103 to change the temperature of the plurality of recesses 103, so that the reaction system solution in the plurality of recesses 103 undergoes a temperature cycle including a denaturation stage, an annealing stage, and an extension stage. For example, an air cooling device may be used to cool it, which has a simple structure and is easy to implement.

[0173] It should be noted that the method 900 may further include more steps, which may be determined according to actual needs, and the embodiments of the present disclosure are not limited to this.

[0174] In the description of this specification, the description with reference to the terms "one embodiment", "another embodiment", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0175] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0176] As will be appreciated by those skilled in the art, although the various steps of the method in the present disclosure are described in a particular order in the accompanying drawings, this does not require or imply that the steps must be performed in this particular order unless the context clearly indicates otherwise. Additionally or alternatively, multiple steps may be combined into one step for execution, and / or a step may be decomposed into multiple steps for execution. In addition, other method steps may be inserted between steps. The inserted steps may represent improvements to the method such as described herein, or may be unrelated to the method. In addition, a given step may not be fully completed before the next step begins.

[0177] The above is only a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. An array substrate, comprising at least one recessed portion, in, The array substrate is located in a plane, and the ratio of the area of ​​the orthographic projection of the at least one recessed portion on the plane to the area of ​​the orthographic projection of the array substrate on the plane is between 0.05 and 0.

60. The array substrate further includes: a first substrate; a defining layer located on the first substrate, defining the at least one recessed portion; a shielding layer defining at least one opening; and A hydrophilic layer and a first hydrophobic layer, The orthographic projection of the at least one opening on the first substrate at least partially overlaps with the orthographic projection of the at least one recessed portion on the first substrate. The orthographic projection of the shielding layer on the first substrate at least partially overlaps with the orthographic projection of the limiting layer on the first substrate. The hydrophilic layer covers the sidewall of the at least one recessed portion, the surface of the limiting layer away from the first substrate, and the bottom of the at least one recessed portion. The first hydrophobic layer is located on a side of the limiting layer away from the first substrate and is further away from the first substrate than the hydrophilic layer. The first hydrophobic layer defines a plurality of holes, the limiting layer defines a plurality of recessed portions, and the shielding layer defines a plurality of openings, and the plurality of holes, the plurality of recessed portions, and the plurality of openings correspond to each other one by one. wherein a first orthographic projection of each of the plurality of holes on the first substrate and a third orthographic projection of an opening corresponding to the hole on the first substrate are both located within a second orthographic projection of a recess corresponding to the hole on the first substrate, and the first orthographic projection, the second orthographic projection and the third orthographic projection form concentric rings, and wherein the first orthographic projection is located between the second orthographic projection and the third orthographic projection, and the third orthographic projection is located within the first orthographic projection.

2. The array substrate according to claim 1, in, The at least one recess penetrates the defining layer.

3. The array substrate according to claim 1 or 2, in, The shielding layer is located between the first substrate and the defining layer.

4. The array substrate according to claim 1 or 2, in, The shielding layer is located on a side of the first substrate away from the defining layer.

5. The array substrate according to claim 1 or 2, in, The shielding layer includes a first portion, the first portion is located on a side of the defining layer away from the first substrate, and is attached to a side surface of the defining layer and a surface away from the first substrate; and Wherein, the first portion defines the at least one opening.

6. The array substrate according to claim 5, in, The shielding layer further includes a second portion, the second portion being attached to a surface of the defining layer close to the first substrate to surround the defining layer together with the first portion; and Wherein, the second portion defines the at least one opening.

7. The array substrate according to claim 6, in, An orthographic projection of the at least one opening defined by the first portion of the shielding layer on the first substrate completely overlaps with an orthographic projection of the at least one opening defined by the second portion of the shielding layer on the first substrate.

8. The array substrate according to any one of claims 1-2 and 6-7, in, A surface of the defining layer close to the first substrate and / or a surface of the defining layer far from the first substrate constitute the shielding layer.

9. The array substrate according to any one of claims 1-2 and 6-7, in, A tangent line at any point on the side wall of the at least one recessed portion forms an angle with the plane on which the array substrate is located, and the angle is not equal to 90°.

10. The array substrate according to any one of claims 1-2 and 6-7, in, The limiting layer defines a plurality of recessed portions, the shielding layer defines a plurality of openings, the plurality of recessed portions correspond one-to-one to the plurality of openings, and an orthographic projection of each of the plurality of openings on the first substrate is located within an orthographic projection of a recessed portion corresponding to the opening on the first substrate.

11. The array substrate according to any one of claims 1 to 2 and 6 to 7, in, A shape of an orthographic projection of each of the at least one recess and each of the at least one opening on the first substrate includes a circle or a regular polygon.

12. The array substrate according to claim 11, in, The limiting layer defines a plurality of recessed portions, the shielding layer defines a plurality of openings, the plurality of recessed portions correspond to the plurality of openings one by one, and an orthographic projection of each of the plurality of openings on the first substrate is located within an orthographic projection of a recessed portion corresponding to the opening on the first substrate; and The orthographic projections of each opening and a recessed portion corresponding to the opening on the first substrate are both circular, the diameter of each opening is in the range of 20 to 80 μm, and the diameter of a recessed portion corresponding to the opening is in the range of 25 to 90 μm; or, the orthographic projection of each opening on the first substrate is a first regular polygon, the orthographic projection of a recessed portion corresponding to the opening on the first substrate is a second regular polygon, the diameter of the inscribed circle of the first regular polygon is in the range of 20 to 80 μm, and the diameter of the inscribed circle of the second regular polygon is in the range of 25 to 90 μm.

13. The array substrate according to any one of claims 1 to 2 and 6 to 7, in, The material of the definition layer includes photoresist.

14. The array substrate according to any one of claims 1 to 2 and 6 to 7, in, The material of the shielding layer includes a light-proof material, and the light-proof material includes chromium, chromium oxide, and black resin.

15. The array substrate according to any one of claims 1 to 2 and 6 to 7, in, The thickness of the shielding layer in a direction perpendicular to the first substrate is in the range of 0.6 to 2.4 μm. 16 . The array substrate according to claim 1 , further comprising a heating electrode located between the first substrate and the defining layer, wherein the heating electrode is configured to heat the at least one recessed portion.

17. The array substrate according to claim 16, in, The material of the heating electrode includes indium tin oxide.

18. The array substrate according to claim 16, in, The heating electrode includes a plurality of sub-portions separated from each other.

19. The array substrate according to claim 16, further comprising a conductive layer, in, The conductive layer is located between the first substrate and the heating electrode and is electrically connected to the heating electrode; and The orthographic projection of at least a portion of the conductive layer on the first substrate falls on the periphery of the orthographic projection of the heating electrode on the first substrate, and the conductive layer at least partially surrounds the heating electrode.

20. The array substrate according to claim 1, in, The ratio of the area of ​​the first hydrophobic layer to the area of ​​the hydrophilic layer is between 0.01 and 2.

00.

21. A microfluidic device, comprising an array substrate according to any one of claims 1 to 20, a counter substrate aligned with the array substrate, and a spacer between the array substrate and the counter substrate, in, The counter substrate comprises: a second substrate; and a second hydrophobic layer located on a side of the second substrate close to the first substrate, Wherein, the counter substrate includes at least one through hole penetrating the second substrate and the second hydrophobic layer.

22. The microfluidic device according to claim 21, in, The material of the first substrate and the second substrate includes glass.

23. The microfluidic device according to claim 21, in, The second hydrophobic layer includes a light absorbing material, and the light absorbing material includes TiO 2 and at least one of TiON.

24. A microfluidic system comprising a control device and a microfluidic device according to any one of claims 21 to 23, in, The control device is electrically connected to the microfluidic device and is configured to control the temperature of the microfluidic device.

25. A fluorescence detection method, include: Accommodating a reagent to be detected in at least one recess of the microfluidic device according to any one of claims 21 to 23; Allowing light of a first wavelength emitted by the light source to irradiate the at least one recessed portion through at least one opening defined by the shielding layer; as well as The light of the second wavelength emitted by the reagent to be detected is detected.

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