CN109174219B

CN109174219B - Microfluidic substrate, driving method thereof and microfluidic device

Info

Publication number: CN109174219B
Application number: CN201811195581.3A
Authority: CN
Inventors: 刘英明; 董学; 王海生; 陈小川; 丁小梁; 顾品超; 张平; 秦云科
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2018-10-15
Filing date: 2018-10-15
Publication date: 2021-12-24
Anticipated expiration: 2038-10-15
Also published as: CN109174219A

Abstract

Embodiments of the present disclosure provide a microfluidic substrate, a driving method thereof, and a microfluidic device. The micro-fluidic substrate comprises a plurality of driving electrodes which are insulated from each other and used for receiving driving signals, each driving electrode comprises an opening area, and the parts of the driving electrodes, which are positioned on two opposite sides of the opening area, have different areas.

Description

Microfluidic substrate, driving method thereof and microfluidic device

Technical Field

Embodiments of the present disclosure relate to a microfluidic substrate, a driving method thereof, and a microfluidic device.

Background

The microfluidic technology is a research hotspot at present, and the micro-fluidic chip can be used for controlling the actions of micro-droplet movement, separation, polymerization, chemical reaction, biological detection and the like.

Disclosure of Invention

At least one embodiment of the present disclosure provides a microfluidic substrate including a plurality of driving electrodes insulated from each other, the driving electrodes for receiving driving signals, each driving electrode including an open region, portions of the driving electrodes on opposite sides of the open region having different areas.

In a microfluidic substrate according to some embodiments of the present disclosure, the plurality of driving electrodes are electrically insulated from each other.

In a microfluidic substrate according to some embodiments of the present disclosure, a vertical centerline of the opening region with respect to a direction is offset from a vertical centerline of the driving electrode with respect to the direction.

In a microfluidic substrate according to some embodiments of the present disclosure, at least one side of the opening region is open, or the opening region is closed.

The microfluidic substrate according to some embodiments of the present disclosure further includes a first substrate on which the driving electrode is disposed, and an auxiliary electrode disposed on the first substrate and insulated from the driving electrode, the auxiliary electrode at least partially overlapping with an opening area of the driving electrode.

In a microfluidic substrate according to some embodiments of the present disclosure, the auxiliary electrode is disposed in the same layer as the driving electrode, and the auxiliary electrode is at least partially located in an opening region of the driving electrode.

In a microfluidic substrate according to some embodiments of the present disclosure, the auxiliary electrode and the driving electrode are disposed in different layers, and the driving electrode is farther from the first substrate than the auxiliary electrode.

In a microfluidic substrate according to some embodiments of the present disclosure, the auxiliary electrode is a slit electrode.

In the microfluidic substrate according to some embodiments of the present disclosure, the slit electrode at least partially overlaps with the opening region of the driving electrode in a direction perpendicular to the first substrate.

In a microfluidic substrate according to some embodiments of the present disclosure, a hydrophobic layer is disposed on a surface of the microfluidic substrate for carrying a droplet.

In a microfluidic substrate according to some embodiments of the present disclosure, a plurality of driving electrodes are arranged in an array of rows and columns.

In a microfluidic substrate according to some embodiments of the present disclosure, a droplet can move in a row direction or a column direction of the array.

The microfluidic substrate according to some embodiments of the present disclosure further includes a plurality of first signal lines and a plurality of second signal lines,

the micro-fluidic substrate further comprises a plurality of first switch elements, the control electrode of each first switch element is electrically connected with one of the plurality of first signal lines, the first electrode of each first switch element is electrically connected with one of the plurality of second signal lines, and the second electrode of each first switch element is electrically connected with at least one driving electrode, so that the first switch elements output driving signals applied by the second signal lines to the at least one driving electrode under the control of the first signal lines.

At least one embodiment of the present disclosure provides a microfluidic device, comprising:

the microfluidic substrate described above; and

and a box aligning substrate arranged opposite to the microfluidic substrate, wherein a channel for liquid drop movement is formed between the box aligning substrate and the microfluidic substrate.

The microfluidic device according to some embodiments of the present disclosure further comprises:

a second substrate base plate; and

an opposite electrode disposed on the second substrate.

In a microfluidic device according to some embodiments of the present disclosure, the pair of cartridge substrates further includes an optical unit disposed on the second substrate, wherein the optical unit overlaps the at least one driving electrode for generating light that illuminates the droplet at the at least one driving electrode.

In a microfluidic device according to some embodiments of the present disclosure, an orthographic projection of the optical unit on the second substrate base overlaps with an orthographic projection of the at least one driving electrode on the second substrate base.

According to at least one embodiment of the present disclosure, there is provided a driving method for the above-mentioned microfluidic substrate, the above-mentioned plurality of driving electrodes including two driving electrodes adjacent to each other in a first direction, the driving method including:

providing a droplet on one of the two drive electrodes and applying a drive signal to the other of the two drive electrodes such that the droplet moves from one of the two drive electrodes to the other of the two drive electrodes.

Drawings

To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below, and it is apparent that the drawings in the following description relate only to some embodiments of the present disclosure and are not limiting to the present disclosure.

Fig. 1 is a schematic plan view of an array of drive electrodes of a microfluidic substrate according to some embodiments of the present disclosure.

Fig. 2 is a schematic cross-sectional view of a microfluidic substrate according to some embodiments of the present disclosure.

Fig. 3A-3C are schematic top views of drive electrodes of microfluidic substrates according to some embodiments of the present disclosure.

Fig. 4 is a schematic top view of a drive electrode of a microfluidic substrate according to further embodiments of the present disclosure.

Fig. 5-7 illustrate a process of driving a microfluidic substrate according to some embodiments of the present disclosure.

Fig. 8 is a schematic plan view of a portion of a microfluidic substrate according to some embodiments of the present disclosure.

Fig. 9 is a schematic side perspective view of a microfluidic substrate according to some embodiments of the present disclosure.

Fig. 10 is a schematic cross-sectional view of a microfluidic substrate according to some embodiments of the present disclosure.

Fig. 11 is a schematic cross-sectional view of a microfluidic substrate according to some embodiments of the present disclosure.

Fig. 12 is a schematic cross-sectional view of a microfluidic device according to some embodiments of the present disclosure.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be described below clearly and completely with reference to the accompanying drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

To maintain the following description of the embodiments of the present disclosure clear and concise, a detailed description of known functions and known components have been omitted from the present disclosure.

In microfluidic systems, it is necessary to control the movement of droplets so that physicochemical reactions, biological detection, etc. can be performed. The microfluidic chip is a main platform for realizing the microfluidic technology, and basic operation units for moving, separating and the like of sample liquid drops can be integrated on the microfluidic chip with the micron scale. The micro-fluidic chip comprises a driving electrode array, the driving electrode array comprises a plurality of driving electrodes arranged in an array, and one driving electrode can be controlled according to needs.

At least one embodiment of the present disclosure provides a microfluidic substrate including a plurality of driving electrodes insulated from each other, the driving electrodes for receiving driving signals, each driving electrode including an open region, portions of the driving electrodes located at opposite sides of the open region having different areas.

Fig. 1 is a schematic plan view of an array of drive electrodes of a microfluidic substrate 100, for example, for forming a microfluidic chip, according to some embodiments of the present disclosure. As shown, the microfluidic substrate 100 includes a plurality of driving electrodes 101, the plurality of driving electrodes 101 are arranged in an electrode array of rows and columns, and the plurality of driving electrodes 101 are insulated from each other. Specifically, the plurality of driving electrodes 101 are electrically insulated from each other. For example, each drive electrode 101 belongs to one drive unit. The electrode array can drive the liquid drop comprising the sample to move along the row direction of the array under the condition of applying a driving signal, and other operations can also be carried out, such as splitting, polymerizing and the like of the liquid drop. Furthermore, it should also be understood that in other embodiments, the plurality of driving electrodes 101 may also be arranged to drive the droplet including the sample to move along the column direction or other directions of the array under the application of the driving signal, which is not limited by the embodiments of the present disclosure.

The following description will be given taking as an example the row direction of the array of drive electrodes 101 as the first direction (the direction indicated by arrow a) in which the liquid droplets are allowed to move. The microfluidic substrate 100 according to some embodiments of the present disclosure further includes a plurality of first signal lines G1-Gm and a plurality of second signal lines D1-Dn. The plurality of first signal lines G1-Gm are connected to, for example, a gate driving circuit, and the plurality of second signal lines D1-Dn are connected to a driving voltage applying circuit. The gate driving circuit may be directly fabricated on the microfluidic substrate 100, for example, or may be fabricated as a separate gate driving chip and then bonded to the microfluidic substrate 100 by means of bonding. Similarly, the driving voltage applying circuit may be directly prepared on the microfluidic substrate 100, for example, or may be prepared as a separate driving voltage applying chip and then bonded to the microfluidic substrate 100 by means of bonding.

Fig. 2 is a schematic cross-sectional view of the microfluidic substrate 100 along line L-L', and for convenience of description, a droplet 200 including a sample is also shown in fig. 2. As shown in fig. 1 and 2, a microfluidic substrate 100 according to some embodiments of the present disclosure includes a plurality of driving electrodes 101 juxtaposed in a first direction. The driving electrodes 101 receive driving signals to drive the droplet 200 to move on the microfluidic substrate 100. Each driving electrode 101 includes an open region 1011. Portions of the driving electrode 101 located at opposite sides of the open region 1011 have different areas. Specifically, the opening area 1011 divides the driving electrode 101 into a first portion 101a facing the first direction (a portion on the left side of the opening area 1011 in fig. 2) and a second portion 101b facing away from the first direction (a portion on the right side of the opening area 1011 in fig. 2) in a first direction (a direction indicated by an arrow a) in which the droplet 200 is allowed to move, and the area of the first portion 101a is larger than that of the second portion 101 b. In various embodiments, the first direction in which the droplets are allowed to move may be any direction, as desired, and embodiments of the present disclosure are not limited in this regard. The area of the first portion 101a mentioned above refers to a projected area of the first portion 101a on the surface of the microfluidic substrate 100, and the area of the second portion 101b mentioned above refers to a projected area of the second portion 101b on the surface of the microfluidic substrate 100.

Fig. 3A-3C are top schematic views of exemplary drive electrodes according to some embodiments of the present disclosure. Although the opening area 2011 of the driving electrode 201 is formed in a rectangular shape in fig. 3A, it should be understood by those skilled in the art that the opening area 2011 may have any shape, and the disclosure is not limited thereto. For example, the opening area 2011 may also be formed in a circular, trapezoidal, or irregular pattern; also for example, the open area 2011 may be closed (as shown in fig. 3A), open on one side (as shown in fig. 3B), or open on both sides (as shown in fig. 3C).

For example, in fig. 3A, the opening area 2011 is closed; in fig. 3B, on the plane of the driving electrode 201, in the direction perpendicular to the first direction (the direction indicated by the arrow a) allowing the droplet to move, one side of the opening area 2011 is open, although it is shown in fig. 3B that the lower side of the opening area 2011 is open, a person skilled in the art should understand that in other embodiments, the upper side of the opening area 2011 may be open, and the embodiment of the present disclosure is not limited thereto; in fig. 3C, the opening area 2011 extends through the driving electrode 201 in a direction perpendicular to the first direction (the direction indicated by the arrow a) in which the droplet is allowed to move on the plane of the driving electrode 201, that is, the opening area is open on both sides in the direction perpendicular to the first direction, and at this time, the first portion 201a and the second portion 201b of the driving electrode 201 can receive the same signal. Further, in some embodiments, a ratio between a width of the opening area 2011 in a direction perpendicular to the first direction (the direction indicated by the arrow a) in which the droplet is allowed to move and a width of the driving electrode 201 in a direction perpendicular to the first direction (the direction indicated by the arrow a) in which the droplet is allowed to move may be greater than a preset value, for example, greater than 0.3, greater than 0.5, greater than 0.8, or the like.

As shown in fig. 3A-3C, line I-I 'is a vertical centerline of the drive electrode 201 as a whole (i.e., including the opening area 2011) with respect to the first direction (the direction indicated by arrow a) in which the liquid droplet is allowed to move, line S-S' is a vertical centerline of the opening area 2011 with respect to the first direction in which the liquid droplet is allowed to move, the vertical centerline S-S 'of the opening area 2011 with respect to the first direction is offset in the first direction away from the first direction as compared to the vertical centerline I-I' of the drive electrode 201 with respect to the first direction, i.e. the perpendicular centre line I-I ' of the rectangular opening area 2011 with respect to the first direction does not overlap the perpendicular centre line S-S ' of the drive electrode 201 with respect to the first direction, the perpendicular centre line S-S ' of the opening area 2011 is offset in a direction opposite to the first direction with respect thereto. A vertical centerline of an object with respect to a direction as referred to herein refers to a line passing through the midpoint of the width of the object in the direction and perpendicular to the direction. Therefore, a vertical center line of the driving electrode 201 with respect to the first direction is a line passing through a midpoint of a width of the driving electrode 201 in the first direction and perpendicular to the first direction; a vertical center line of the opening region 2011 with respect to the first direction is a line passing through a midpoint of a width of the opening region 2011 in the first direction and perpendicular to the first direction. The opening region 2011 divides the driving electrode 201 into a first portion 201a facing the first direction (located at a right portion of the opening region 2011 in fig. 3A to 3C) and a second portion 201b facing away from the first direction (located at a left portion of the opening region 2011 in fig. 3A to 3C), the first portion 201a has an area larger than that of the second portion 201b, and in the case shown in the drawings, the width of the first portion 201a in the first direction is larger than that of the second portion 201b in the first direction. Furthermore, those skilled in the art will appreciate that the rectangular shape of the driving electrode 201 in fig. 3A-3C is merely exemplary, and the driving electrode 201 may have any suitable shape as desired.

Furthermore, although in fig. 3A-3B, the first portion 201a of the driving electrode 201 located at the right side of the opening area 2011 (i.e., located at the side of the opening area 2011 facing the first direction) and the second portion 201B located at the left side of the opening area 2011 (i.e., located at the side of the opening area 2011 facing away from the first direction) are connected together to achieve electrical connection, in other embodiments, as shown in fig. 3C, the first portion 201a and the second portion 201B of the driving electrode 201 may also be separated, and in the case that the first portion 201a and the second portion 201B of the driving electrode 101 are separated from each other, the first portion 201a and the second portion 201B of the driving electrode 201 receive the same driving signal to drive the droplet to move or separate. In the example of fig. 3C, in order to make the first portion 201a and the second portion 201b of the driving electrode 201 receive the same driving signal, for example, both may be connected to an electrode of the same switching element, or connected through a bridge electrode provided in a different layer, or, although connected to different switching electrodes, the different switching electrodes receive the same driving signal.

Furthermore, although in fig. 3A to 3C, the opening region 2011 of the driving electrode 201 is shown to include only one opening, in some embodiments of the present disclosure, the opening region 2011 of the driving electrode 201 may also include a plurality of openings, which is not limited by the embodiments of the present disclosure.

FIG. 4 is a schematic top view of a drive electrode according to further embodiments of the present disclosure. As shown in fig. 4, the opening region 2011 'of the driving electrode 201' has a planar shape protruding toward the first direction (the direction indicated by the arrow a) in which the liquid droplet is allowed to move, so that the movement or separation of the liquid droplet in the first direction (the direction indicated by the arrow a) can be more easily achieved. A line I-I ' in fig. 4 is a vertical center line of the driving electrode 201 ' with respect to the first direction (the direction indicated by the arrow a), a line S-S ' is a vertical center line of the opening area 2011 ' with respect to the first direction, the opening area 2011 ' divides the driving electrode 201 ' into a first portion 201a ' located on the right side of the opening area 2011 ' (i.e., on the side of the opening area 2011 ' facing the first direction) and a second portion 201b located on the left side of the opening area 2011 ' (i.e., on the side of the opening area 2011 ' facing away from the first direction), and the area of the first portion 201a ' is larger than that of the second portion 201b '.

Referring again to fig. 1 and 2, the microfluidic substrate 100 according to some embodiments of the present disclosure further includes a first substrate 102. The first substrate base plate 102 may be made of a rigid material or a flexible material. For example, the first substrate board 102 may be made of glass, ceramic, silicon, polyimide, or the like. The first substrate base plate 102 may support elements formed thereon.

The microfluidic substrate 100 according to some embodiments of the present disclosure may further include a plurality of first switching elements for respectively providing driving signals to the plurality of driving electrodes 101. For example, a plurality of first switching elements are in one-to-one correspondence with the plurality of driving electrodes 101, and are combined to obtain a plurality of driving units. As an example, in fig. 1 and 2, the first switching element is illustrated in the form of a thin film transistor, however, it may be understood by those skilled in the art that the first switching element may be implemented in other forms, and the present disclosure is not limited thereto.

As shown in fig. 1 and 2, the first switching element exemplified by a thin film transistor may include a gate electrode 103, a gate insulating layer 104, an active layer 105, a first pole 106, and a second pole 107. As an example, in the embodiment of the present disclosure, the first pole 106 is a source electrode and the second pole 107 is a drain electrode, however, the present disclosure does not limit this. An insulating layer or dielectric layer 108 is formed between the driving electrode 101 and the thin film transistor. The first portion 101a of the drive electrode 101 is in electrical contact with the second pole 107 through a via in the insulating layer 108. In other embodiments, it is also possible that the second portion 101b of the driving electrode 101 is electrically contacted to the second pole 107 through a via in the insulating layer 108, or that both the first portion 101a and the second portion 101b of the driving electrode 101 are electrically contacted to the second pole 107 through a via in the insulating layer 108, which is not limited by the present disclosure.

Further, in still other embodiments, in the case where the first and

second portions

101a and 101b of the driving electrode 101 are separated (see fig. 3C), the first and

second portions

101a and 101b of the driving electrode 101 may also be driven by two different thin film transistors connected to the same data and gate lines.

In fig. 1, the first switching element is illustrated by taking a thin film transistor as an example, and the first signal lines G1-Gm are gate lines and the second signal lines D1-Dn are data lines. The control electrode (i.e., the gate electrode) of the thin film transistor is electrically connected to one of the first signal lines G1-Gm, the first electrode of the thin film transistor is electrically connected to one of the second signal lines D1-Dn, and the second electrode of the thin film transistor is electrically connected to the driving electrode 101, so that the thin film transistor outputs the driving signal applied from the second signal line to the driving electrode 101 under the control of the first signal line.

Although one first switching element is electrically connected to one driving electrode 101 in fig. 1, according to actual needs, in some embodiments, one first switching element may be electrically connected to a plurality of driving electrodes 101, so that the plurality of driving electrodes 101 can receive the same driving signal at the same time, thereby providing a larger driving force.

Referring to fig. 2, the microfluidic substrate 100 according to some embodiments of the present disclosure may further include a hydrophobic layer 110, the hydrophobic layer 110 being formed on a surface of the microfluidic substrate 100 for carrying the droplet 200. The penetration of the droplet 200 into the microfluidic substrate 100 may be prevented by the hydrophobic layer 110, reducing the loss of the droplet 200, and facilitating the movement of the droplet 200 on the microfluidic substrate 100. The water-repellent layer 110 may be directly formed on the surface of the driving electrode 101, or an insulating layer 109 may be further formed between the water-repellent layer 110 and the driving electrode 101, whereby the driving electrode 101 may be electrically insulated from the droplet 200. The insulating layer 109 may also function as a planar layer so that the microfluidic substrate 100 has a planar surface. In some exemplary embodiments, the hydrophobic layer 110 may be formed of teflon (teflon), and the insulating layer 109 may be formed of an inorganic insulating material or an organic insulating material, for example, a resin, but the present disclosure is not limited thereto.

Some embodiments of the present disclosure also provide a driving method for the microfluidic substrate described above, the method including: for a droplet provided on one of the two drive electrodes, a drive signal is applied to the other of the two drive electrodes such that the droplet moves from the one of the two drive electrodes to the other of the two drive electrodes, wherein the two drive electrodes are adjacent to each other in the first direction.

A driving method for a microfluidic substrate according to some embodiments of the present disclosure will be described below with reference to fig. 5 to 7.

A driving method for a microfluidic substrate according to some embodiments of the present disclosure will be explained in fig. 5 to 7 based on the microfluidic substrate 100 shown in fig. 1 and 2, in which the driving electrode 101 is an example of one of two driving electrodes adjacent to each other in a first direction allowing a droplet to move, and the driving electrode 101' is an example of the other of the two driving electrodes.

As shown in fig. 5, in a first period of time, when the control electrode of the first switching element electrically connected to the driving electrode 101 receives a turn-on signal, the first electrode and the second electrode of the first switching element are turned on, and the first electrode of the first switching element connected to the data line receives the driving signal, so that the second electrode of the first switching element provides the driving electrode 101 with the driving signal, and since the driving electrode 101 is inputted with a voltage, for example, with a positive charge, a corresponding negative charge is coupled to the lower portion of the droplet 200 located above the driving electrode 101. Since the drive electrode 101 has an open area 1011, the negative charge coupled out at the lower part of the droplet 200 will also have an uneven distribution. Specifically, as shown in fig. 5, the portion of the droplet 200 corresponding to the first portion 101a couples out more negative charge than the portion of the droplet 200 corresponding to the second portion 101 b.

As shown in fig. 6, in the second period, when the control electrode of the first switching element electrically connected to the driving electrode 101 'receives the turn-on signal, the first electrode and the second electrode of the first switching element are turned on, and the first electrode of the first switching element connected to the data line at this time receives the driving signal, so that the second electrode of the first switching element provides the driving signal to the driving electrode 101', and no driving signal is input to the driving electrode 101 at this time, or the driving electrode 101 is grounded or discharged by applying a negative driving signal. Here, the second period of time is later than the first period of time. The driving electrode 101' and the driving electrode 101 are adjacent to each other in a first direction (e.g., the direction indicated by the arrow a). In the second time period, since the driving electrode 101 'is inputted with a voltage, for example, with a positive charge, and the lower portion of the droplet 200 is charged with a negative charge, the droplet 200 moves toward the driving electrode 101' in the direction indicated by the arrow a by the attraction force between the positive charge and the negative charge.

In some embodiments, in the second time period, the droplet 200 moves to be located directly above the drive electrode 101'. Since the side of the droplet 200 closer to the drive electrode 101 ' has more charge than the side of the droplet 200 farther from the drive electrode 101 ', the droplet 200 moves more easily in the direction indicated by arrow a toward the drive electrode 101 '.

Furthermore, in some embodiments, during the second time period, the charge attraction between the droplet 200 and the drive electrode 101' may also cause the droplet 200 to be separated.

At the end of the second period of time, the droplet 200 is positioned over the drive electrode 101', as shown in fig. 7. In some embodiments, at the end of the second time period, the droplet 200 may be located directly above the drive electrode 101', although embodiments of the present disclosure are not limited in this regard. Thereafter, the above operation may be repeated, and the droplet 200 may continue to move to other driving units along the first direction.

Fig. 8 is a schematic plan view of a portion of a microfluidic substrate according to some embodiments of the present disclosure. A microfluidic substrate according to some embodiments of the present disclosure includes a plurality of detection cells 702. The plurality of detection cells 702 may be arranged in an array of rows and columns, and each detection cell 702 corresponds to one or more drive electrodes 101. For example, in these embodiments, the detection units may correspond one-to-one to the drive units, the detection units may be arranged in an array of the same specification as the drive units, or the number of detection units may be smaller than the drive units, for example, the array of detection units is more sparse than the array of drive units.

As in the example shown in fig. 8, each detection unit 702 at least partially overlaps the drive electrode 101 of one drive unit for enabling detection of the droplet 200 when the droplet 200 is located at the drive electrode 101, the detection result being used to obtain characteristic information of the droplet 200. A control electrode of the first switching element 701 of the driving unit is electrically connected to the first signal line L1, a first electrode of the first switching element 701 is electrically connected to the second signal line L2, and a second electrode of the first switching element 701 is electrically connected to the driving electrode 101. The detection unit 702 includes a sensor 7022 and a second switching element 7021, a control pole of the second switching element 7021 is electrically connected to the third signal line L3, a first pole of the second switching element 7021 is electrically connected to the fourth signal line L4, and a second pole of the second switching element 7021 is electrically connected to the sensor 7022, so that the second switching element 7021 outputs an electric signal generated by the sensor 7022 to the fourth signal line L4 under the control of the third signal line L3.

In some exemplary embodiments, the second switching element 7021 may be implemented as a thin film transistor, the control electrode of the second switching element 7021 may be a gate electrode, and the first and second electrodes of the second switching element 7021 may be a source electrode and a drain electrode, respectively, or may be a drain electrode and a source electrode, which is not limited by the present disclosure. For example, the gate layer, the active layer, and the source/drain electrode layer of the first switching element 701 and the second switching element 7021 are at least partially disposed in the same layer (the same layer is formed by the same material and simultaneously by a single patterning process), so that the manufacturing process can be simplified, which will be described in detail below with reference to fig. 9.

Although it is shown in fig. 8 that one sensing cell 702 partially overlaps one driving electrode 101, it will be understood by those skilled in the art that each sensing cell 702 may also overlap a plurality of driving electrodes 101, so that the number of sensing cells may be reduced. The sensor 7022 may comprise one or more sensors. For example, the sensor 7022 may receive a photoelectric sensor that irradiates light passing through the droplet to generate an electric signal, a temperature sensor that detects the temperature of the droplet to generate an electric signal, or the like, according to actual needs.

In one exemplary embodiment, the sensor 7022 may include a photodiode, which may be of various types, such as PN-type, PIN-type, MSM-type, and the like, and embodiments of the present disclosure are not limited thereto. The sensor 7022 may further include a storage capacitor, a switching transistor, or further include an amplifying transistor, etc., as needed, which is not limited by the embodiments of the present disclosure. In case the detection unit 702 comprises a photosensor, the drive electrode 101 may be at least partially transparent, such that light passes through the drive electrode 201 to the photosensor to be received and detected by the photosensor sensor. For example, the driving electrode 101 may be made of a transparent conductive material such as Indium Tin Oxide (ITO). In some embodiments, different sensors 7022 may also be provided at different locations or in different areas of the microfluidic substrate to achieve different detection requirements.

As shown in fig. 8, the microfluidic substrate according to some embodiments of the present disclosure may further include a signal processing device 703. The signal processing device 703 is in signal connection with the detection unit 702, here connected through a fourth signal line L4, to transmit the electrical signal generated by the detection unit 702 to the signal processing device 703, and the signal processing device 703 is configured to obtain characteristic information of the liquid droplet based on the detection result of the detection unit 702. In some embodiments, the characteristic information may include at least one of position information, shape information, concentration information, and temperature information.

In fig. 8, a wired connection is shown between the signal processing device 703 and the detection unit 702, however, it should be understood by those skilled in the art that a wireless connection, such as a bluetooth connection, a wifi connection, etc., may also be formed between the signal processing device 703 and the detection unit 702, and the disclosure is not limited thereto. The signal processing device 703 may be implemented by, for example, a central processing unit, an application specific integrated circuit, a field programmable gate array, or the like.

The operation principle of the microfluidic substrate 100 provided by some embodiments will be described below by taking the size, position, and concentration detection of the droplet as an example. For example, in the case where the sensor 7022 of the detection unit 702 includes a photosensor (e.g., a photodiode), when the droplet 200 moves to a certain position on the microfluidic substrate 100, the droplet 200 is located above a portion of the photosensor, and thus the portion of the photosensor is shielded, so that incident light of the portion of the photosensor is changed, and thus an electrical signal output by the portion of the photosensor is changed, and based on this, information such as the position, size, shape, and the like of the droplet 200 can be obtained by analyzing the electrical signals of the detection unit array. In addition, since the intensity of the light blocked by the liquid drops 200 with different concentrations is different, the incident light intensity of different areas of the detection cell array is different, and therefore, the concentration information of the liquid drops 200 can be obtained by analyzing the electric signals of the detection cell array based on the incident light intensity.

In some embodiments, if the detected droplet 200 is large and may cover more than one detection unit, the signal processing device 703 may integrate the detection signals output by the plurality of detection units for analysis.

Fig. 9 is a schematic side perspective view of a microfluidic substrate according to some embodiments of the present disclosure, for example corresponding to the situation shown along line T-T' in fig. 8.

In fig. 9, a first switching element 910 and a second switching element 920 are illustrated as a thin film transistor. The first switching element 910 includes a gate electrode 911, a gate insulating layer 912, an active layer 913, a first pole 914 and a second pole 915, and the second switching element 920 includes a gate electrode 921, a gate insulating layer 912, an active layer 922, a first pole 923 and a second pole 925. The first switching element 910 and the second switching element 920 share the same gate insulating layer, i.e., the gate insulating layer 912. The gate electrode 911 of the first switching element 910 and the gate electrode 921 of the second switching element 920 are formed on the first substrate 9001 at the same layer. The active layer 913, the first pole 914, and the second pole 915 of the first switching element 910 and the active layer 922, the first pole 923, and the second pole 925 of the second switching element 920 are respectively formed on the gate insulating layer 912 in the same layer. A first passivation layer 9003 covers the active layer 913, the first and

second poles

914 and 915 of the first switching element 910 and the active layer 922, the first and second poles 923 and 925 of the second switching element 920. The driving electrode 9009 is in electrical contact with the metal layer 9007 through vias formed in the barrier layer 9008, the metal layer 9007 is in electrical contact with the electrode 9002 through vias formed in the second passivation layer 9006 and the capping layer 9004, and the electrode 9002 is in electrical contact with the second pole 915 of the first switching element 910, so that the driving electrode 9009 can receive a driving signal from the second pole 915 of the first switching element 910. A resin layer 9010 and a water-repellent layer 9011 may also be formed over the driving electrode 9009, and a resin layer 9005 may also be formed between the cover layer 9004 and the second passivation layer 9006.

In addition, in fig. 9, the detection unit 930 is illustrated with a photodiode as an example. The sensing unit 930 includes a lower electrode 931, a photodiode (PIN type) 932, a cap layer 933, and an upper electrode 934. And the lower electrode 931 is in electrical contact with the second pole 924 of the second switching element 920 so that the sensing unit 930 can output an electrical signal through the second switching element 920. The upper electrode 934 may have a fixed potential and is electrically insulated from the drive electrode 9009 by a barrier layer 9008. The driving electrode 9009 and the cap layer 933 may both be formed of a transparent conductive material such as Indium Tin Oxide (ITO) so that light may reach the photodiode 932 through the driving electrode 9009 and the cap layer 933.

As shown in fig. 9, the driving electrodes 9009 may overlap the detection unit 930 in a direction perpendicular to the surface of the microfluidic substrate, such that when a droplet moves to the driving electrodes 9009, the droplet may also at least partially overlap the detection unit 930 in the direction perpendicular to the surface of the microfluidic substrate.

The microfluidic substrate described above with reference to fig. 9 and other embodiments of the microfluidic substrate may be fabricated by semiconductor processes, such as deposition, etching, etc., and will not be described in detail herein.

Fig. 10 is a schematic cross-sectional view of a microfluidic substrate 800 according to some embodiments of the present disclosure. The microfluidic substrate 800 is substantially the same as the microfluidic substrate 100 except that the microfluidic substrate 800 further includes an auxiliary electrode 111. The auxiliary electrode 111 at least partially overlaps with the open region 1011 of the driving electrode 101 in a direction perpendicular to the surface of the first substrate 102. The auxiliary electrode 111 is electrically insulated from the driving electrode 101. The driving electrode 101 may be located above the auxiliary electrode 111 in a direction perpendicular to the surface of the first substrate 102, that is, the driving electrode 101 is closer to the droplet 200 than the auxiliary electrode 111. The auxiliary electrodes 111 may be provided individually for each driving electrode 101, that is, the auxiliary electrodes 111 corresponding to different driving electrodes 101 may be spaced apart from each other, or a common auxiliary electrode 111 may be provided collectively for a plurality of driving electrodes 101, that is, the auxiliary electrodes 111 corresponding to different driving electrodes 101 may be connected or formed in one body. The auxiliary electrode 111 may be formed of various suitable conductive materials, for example, Indium Tin Oxide (ITO) in order to allow light to transmit therethrough. The auxiliary electrodes 111 may be connected to electrode lines (not shown), and in operation, the auxiliary electrodes 111 have a fixed potential, e.g. are applied with a common voltage or grounded, etc., so that the auxiliary electrodes 111 may form an electric field substantially transverse (i.e. parallel to the surface of the microfluidic substrate 800) over the surface of the microfluidic substrate 800 (e.g. over the hydrophobic layer 110 in fig. 9), thereby facilitating a more non-uniform distribution of the charge coupled out of the lower portion of the droplet 200 and facilitating a movement of the droplet 200 in a first direction (e.g. the direction indicated by arrow a). The operation principle of the microfluidic substrate 800 is similar to that of the microfluidic substrate 100, and the details of the disclosure will not be repeated.

Fig. 11 is a schematic cross-sectional view of a microfluidic substrate 900 according to some embodiments of the present disclosure. The microfluidic substrate 900 is substantially the same as the microfluidic substrate 800 except that the auxiliary electrodes 111' are formed in the open regions 1011 of the driving electrodes 101. Although the auxiliary electrode 111 'is formed in the open region 1011 of the driving electrode 101, the auxiliary electrode 111' is electrically insulated from the driving electrode 101. In some embodiments, the auxiliary electrode 111 'may occupy a portion of the open region 1011, while in other embodiments, the auxiliary electrode 111' may occupy the entire open region 1011, which is not limited by the present disclosure. The operation principle of the microfluidic substrate 900 is similar to that of the microfluidic substrate 100, and the details of the disclosure will not be repeated.

In some embodiments of the present disclosure, the auxiliary electrode may be a slit electrode, and the non-slit portion of the auxiliary electrode at least partially overlaps the opening region of the driving electrode in a direction perpendicular to the first substrate base plate.

Fig. 12 is a schematic cross-sectional view of a microfluidic device 1000 according to some embodiments of the present disclosure. The microfluidic device is for example realized as a microfluidic chip. The microfluidic device includes the microfluidic substrate (e.g., the microfluidic substrate 100) in the above-described embodiment and the opposing-cartridge substrate 300 disposed opposite to the microfluidic substrate. As shown in fig. 12, spaces for the movement of the droplet 200 are formed between the pair of cartridge substrates 300 and the microfluidic substrate 100, and the spaces may be divided into different channels extending in the first direction.

The opposing base plate 300 may include a second substrate base plate 301. The second substrate base 301 may be made of a rigid material or a flexible material. For example, the second base substrate 301 may be made of glass, ceramic, silicon, polyimide, or the like. The second substrate base 301 is formed of the same or different material as the first substrate base 102, which is not limited by the present disclosure.

In some embodiments, the microfluidic device 1000 may also include a counter electrode 302. The counter electrode 302 is provided on the second substrate board 301. In operation, counter electrode 302 may be applied with a drive signal, ground or a common voltage to form an electric field between drive electrode 101 and counter electrode 302 in operation, thereby for example driving droplet 200 to move. In addition, the counter electrode 302 may also function to shield an external electromagnetic field. The counter electrode 302 may be a planar electrode, a slit electrode, or a plurality of block electrodes connected together.

The counter-cell substrate 300 may further include an insulating layer 303 to insulate the counter electrode 302 from the droplet 200. The counter-cell substrate 300 may further include a hydrophobic layer 304 to prevent the droplet 200 from penetrating the insulating layer 303, the counter electrode 302, and/or the second substrate 301, to reduce the loss of the droplet 200, and to facilitate the movement of the droplet 200. The insulating layer 303 may be located between the counter electrode 302 and the hydrophobic layer 304. In some exemplary embodiments, the hydrophobic layer 304 may be formed of teflon (teflon) and the insulating layer 303 may be formed of resin, but the present disclosure is not limited thereto. The opposite electrode 302 may be formed of any suitable material such as metal, Indium Tin Oxide (ITO), and the like.

In the microfluidic device 1000, the microfluidic substrate 100 may be bonded to the opposite cartridge substrate 300 using an adhesive to form a cartridge in which the droplet 200 may move. In some embodiments, one or more spacers 305 may also be formed between the microfluidic substrate 100 and the cartridge-opposing substrate 300 to define a channel for the movement of the droplet 200. Meanwhile, the spacer 305 may also function to maintain the distance between the microfluidic substrate 100 and the counter cassette substrate 300. The spacer 305 may be formed of a resin (e.g., a photosensitive resin) or the like, and may be formed in a columnar shape, a long dam shape, or the like.

In some embodiments, the microfluidic device 1000 may further include an optical unit disposed on the second substrate base 301. In some embodiments, as shown in fig. 12, the optical unit may include a light source 306 and a light guide plate 307, thereby obtaining a surface light source, which may provide light for detection to all or part of the detection units on the microfluidic substrate 100, for example. In some embodiments, the optical unit may further include a light extraction unit 308, the light extraction unit 308 for providing detection light at a specific location. For example, the light extraction unit 308 overlaps at least one drive electrode 101 for generating light that illuminates the droplet 200 at the at least one drive electrode 101. In some embodiments, the orthographic projection of the optical unit on the second substrate 301 overlaps with the orthographic projection of the at least one drive electrode 101 on the second substrate. Light source 306 is used to emit light for illuminating droplet 200. For example, the light source 306 may be a point light source, a line light source, or the like, and may be, for example, a Light Emitting Diode (LED), a Cold Cathode Fluorescent Lamp (CCFL), or the like. In some embodiments, the light source 306 may also be a laser light source that emits laser light, such as a laser diode or the like. The light guide plate 307 serves to guide light emitted from the light source 306. For example, the light guide plate 307 may be made of glass or plastic. The light source 306 may be designed to emit parallel light in a predetermined direction, which is incident from the incident surface of the light guide plate 307 at a predetermined angle, satisfying a total reflection condition, so as to be laterally propagated within the light guide plate 307.

The light extracting unit 308 is configured to extract light in the light guide plate 307 and emit the light toward the driving electrode 101. In some embodiments, the light extraction unit 308 may be implemented by a grating, for example. The light guiding unit 308 can make different wavelengths and different intensities of light exit toward the driving electrode 101 through different grating structures. In other embodiments, the light outlet unit 308 may be implemented by forming a plurality of notches, roughness, grooves, or the like on the surface of the light guide plate 307, for example, by breaking the total reflection condition of light in the light guide plate through these structures, so that the light is emitted from the light outlet unit 308. In still other embodiments, a light shielding layer (e.g., a reflective layer, etc.) may be formed on the surface of the light guide plate 307, and the light extraction unit 308 may be implemented by openings formed in the light shielding layer, at which the light propagating in the light guide plate 307 may be extracted. It will be appreciated by those skilled in the art that the light-out unit 308 may also be embodied in other forms, and the present disclosure is not limited to the above-described embodiments.

Those skilled in the art will appreciate that the positions of the light source 306, the light guide plate 307, and the light out-guiding unit 308 are exemplarily illustrated in fig. 12, and the present disclosure is not limited thereto. For example, the positions of the light guide plate 307 and the light extraction unit 308 may also be located between the second substrate base 301 and the counter electrode 302, between the counter electrode 302 and the insulating layer 303, between the insulating layer 303 and the hydrophobic layer 304, or the like.

The light emitted from the light source 306 passes through the light guide plate 307 and the light extraction unit 308 (e.g., a grating) and then is irradiated onto the droplet 200 or the detection unit (e.g., a photosensor) in the microfluidic substrate 100. Because different light irradiates the detection unit, the detection unit can generate different output signals, so that the detection unit generates a detection result according to input light and transmits the detection result to the signal processing device, and the signal processing device analyzes the detection result, thereby realizing the measurement of the position, the shape, the concentration and the like of the liquid drop 200.

In other embodiments of the present disclosure, the optical unit in the microfluidic device 1000 may also be a surface light source, such as an LED array, a flat fluorescent lamp (VFD), an electroluminescent sheet (ELD), etc., disposed on the second substrate 301, with the light emitting surface facing the microfluidic substrate 100, in which case elements such as a light guide plate may be omitted, thereby simplifying the structure of the microfluidic device 1000.

It will be understood by those skilled in the art that the microfluidic substrate 800 or the microfluidic substrate 900 described above may also be used in place of the microfluidic substrate 100 in the microfluidic device 1000.

The above description is only a specific embodiment of the present disclosure, but the scope of the present disclosure is not limited thereto, and the scope of the present disclosure should be subject to the scope of the claims.

Claims

1. A microfluidic substrate comprising a plurality of driving electrodes insulated from each other, the driving electrodes being configured to receive a driving signal, each of the driving electrodes including an open region, portions of the driving electrodes located on opposite sides of the open region in a first direction having different areas, and the driving electrodes being asymmetric in the first direction;

the micro-fluidic substrate further comprises a first substrate and an auxiliary electrode, wherein the driving electrode is arranged on the first substrate, the auxiliary electrode is arranged on the first substrate and insulated from the driving electrode, and the auxiliary electrode at least partially overlaps with the driving electrode and an opening area of the driving electrode.

2. The microfluidic substrate according to claim 1, wherein a vertical centerline of the open area with respect to a direction is offset from a vertical centerline of the driving electrode with respect to the direction.

3. The microfluidic substrate according to claim 1, wherein at least one side of the open region is open or the open region is closed.

4. The microfluidic substrate according to claim 1, wherein the auxiliary electrode and the driving electrode are disposed in different layers, and the driving electrode is farther from the first substrate than the auxiliary electrode.

5. The microfluidic substrate according to claim 1, wherein the auxiliary electrode is a slit electrode.

6. The microfluidic substrate according to claim 1, wherein a hydrophobic layer is disposed on a surface of the microfluidic substrate for carrying the droplet.

7. The microfluidic substrate according to any one of claims 1-6, wherein the plurality of driving electrodes are arranged in an array of rows and columns.

8. The microfluidic substrate according to any one of claims 1-6, further comprising a plurality of first signal lines and a plurality of second signal lines,

the micro-fluidic substrate further comprises a plurality of first switch elements, a control electrode of each first switch element is electrically connected with one of the plurality of first signal lines, a first electrode of each first switch element is electrically connected with one of the plurality of second signal lines, and a second electrode of each first switch element is electrically connected with at least one driving electrode, so that the first switch elements output driving signals applied by the second signal lines to at least one driving electrode under the control of the first signal lines.

9. A microfluidic device comprising:

the microfluidic substrate of any one of claims 1 to 8; and

and the box aligning substrate is arranged opposite to the microfluidic substrate, and a channel for liquid drop movement is formed between the box aligning substrate and the microfluidic substrate.

10. The microfluidic device of claim 9, further comprising:

a second substrate base plate; and

and a counter electrode provided on the second substrate base plate.

11. The microfluidic device according to claim 10, the pair of cartridge substrates further comprising an optical unit disposed on the second substrate, wherein an orthographic projection of the optical unit on the second substrate overlaps with an orthographic projection of at least one of the driving electrodes on the second substrate for generating light illuminating the droplet at the at least one of the driving electrodes.

12. A driving method for the microfluidic substrate of any one of claims 1-8, the plurality of driving electrodes comprising two driving electrodes adjacent to each other, the driving method comprising:

providing a droplet on one of the two drive electrodes, applying a drive signal to the other of the two drive electrodes such that the droplet moves from the one of the two drive electrodes to the other of the two drive electrodes.