CN118142603A - Microfluidic chip and preparation method thereof - Google Patents

Abstract

The application provides a microfluidic chip and a preparation method of the microfluidic chip, wherein the microfluidic chip comprises a bearing substrate, a cover layer, a thin film transistor driving component and a transition driving component, the cover layer is arranged on the bearing substrate and comprises a horizontal part and a deformation part which are connected, the thin film transistor driving component is arranged between the cover layer and the bearing substrate and corresponds to the horizontal part of the cover layer, the transition driving component is arranged between the cover layer and the bearing substrate and corresponds to the deformation part of the cover layer, and the transition driving component is matched with the thin film transistor driving component to drive micro liquid drops to move from the horizontal part to the deformation part or from the deformation part to the horizontal part. The micro-droplet can move from the horizontal part to the deformation part or from the deformation part to the horizontal part only by providing a small driving force due to self gravity, and the thin film transistor driving assembly only needs to provide a small driving voltage, so that the thin film transistor driving assembly can be conveniently and effectively applied to the field of micro-flow control.

Description

A microfluidic chip and a method for preparing the same

Technical Field

The present application relates to the field of microfluidic technology, and specifically to a microfluidic chip and a method for preparing the microfluidic chip.

Background technique

Microfluidics is a technology that precisely controls and manipulates microscale fluids. It can integrate basic operating units such as sample preparation, reaction, separation, and detection in the biochemical analysis process onto a micrometer-scale chip, automatically completing the entire analysis process. Microfluidics has the advantages of low sample consumption, fast detection speed, simple operation, multifunctional integration, small size, and easy portability. It has great application potential in biology, chemistry, medicine, and other fields.

Among the related technologies, thin film transistor driven backplane technology is mature and has low preparation cost, and can be used to drive the movement of microdroplets. However, the driving voltage required for the movement of microdroplets is relatively high, which limits the application of thin film transistor driven backplane technology in microfluidic technology.

Summary of the invention

The purpose of the present application is to provide a microfluidic chip and a method for preparing the microfluidic chip, so as to solve the technical problem in the related art that the thin film transistor driving backplane technology is difficult to apply to the microfluidic field.

In a first aspect, the present application provides a microfluidic chip for controlling the movement of microdroplets, comprising:

A carrier substrate;

A covering layer, disposed on the supporting substrate, the covering layer is used to support the micro-droplets, and the covering layer includes a connected horizontal portion and a deformation portion;

a thin film transistor driving component, disposed between the cover layer and the carrier substrate, and arranged corresponding to the horizontal portion of the cover layer; and

A transition drive component is disposed between the cover layer and the carrier substrate and is arranged corresponding to the deformation portion of the cover layer. The transition drive component cooperates with the thin film transistor drive component to drive the micro-droplet to move from the horizontal portion to the deformation portion or from the deformation portion to the horizontal portion.

In the microfluidic chip provided by the present application, the covering layer includes a connected horizontal portion and a deformable portion, the thin film transistor driving component is arranged corresponding to the horizontal portion of the covering layer, the transition driving component is arranged corresponding to the deformable portion of the covering layer, and the transition driving component cooperates with the thin film transistor driving component to drive the micro droplets to move from the horizontal portion to the deformable portion or from the deformable portion to the horizontal portion. Due to the gravity of the micro droplets themselves, the thin film transistor driving component only needs to provide a small driving force to move from the horizontal portion to the deformable portion or from the deformable portion to the horizontal portion, and the thin film transistor driving component only needs to provide a small driving voltage, which is convenient for the thin film transistor driving component to be effectively used in the field of microfluidics.

Wherein, the deformable portion is a groove portion, and the groove portion extends in a direction toward the supporting substrate; or, the deformable portion is a protrusion portion, and the protrusion portion extends in a direction away from the supporting substrate.

Among them, the microfluidic chip also includes a flat layer, which is arranged between the covering layer and the supporting substrate, and the flat layer covers the source layer, the drain layer and the active layer of the thin film transistor driving component. The portion of the flat layer close to the transition driving component has an inclined surface, and the inclined surface is inclined in a direction close to the transition driving component in a direction close to the supporting substrate, or the inclined surface is inclined in a direction close to the supporting substrate in a direction away from the transition driving component.

Among them, the microfluidic chip also includes a gate insulating layer, which is arranged on the supporting substrate and covers the gate layer of the thin film transistor driving component. The source layer, the drain layer, the active layer and the transition driving component are arranged on the gate insulating layer; the flat layer also includes a via, and the driving electrode layer of the thin film transistor driving component is connected to the drain layer through the via.

Among them, the transition driving component includes a signal transmission layer and a transition electrode layer, the transition electrode layer is arranged on the side of the signal transmission layer away from the carrying substrate, the signal transmission layer and the source layer of the thin film transistor driving component are prepared through one process, and the transition electrode layer and the driving electrode layer of the thin film transistor driving component are prepared through one process.

Wherein, the driving electrode layer further includes an extending portion, the extending portion extends to the inclined surface of the flat layer, and at least a portion of the extending portion is disposed on the inclined surface and corresponding to the deformable portion of the covering layer.

The microfluidic chip further comprises a first data line and a second data line, wherein the first data line is connected to the source layer of the thin film transistor driving component, and the second data line is connected to the signal transmission layer of the transition driving component.

In a second aspect, the present application provides a method for preparing a microfluidic chip, which is used to prepare the microfluidic chip, comprising:

providing a carrier substrate;

forming a thin film transistor driving component and a transition driving component on the carrier substrate;

A covering layer is formed on the thin film transistor driving component and the transition driving component, wherein the covering layer includes a horizontal portion and a deformation portion connected to each other, the horizontal portion is arranged corresponding to the thin film transistor driving component, and the deformation portion is arranged corresponding to the transition driving component.

Wherein, the preparation method of the microfluidic chip further comprises:

forming a flat layer;

An inclined surface is formed on a portion of the flat layer close to the transition drive assembly, wherein the inclined surface is inclined in a direction close to the carrier substrate in a direction close to the transition drive assembly, or the inclined surface is inclined in a direction close to the carrier substrate in a direction away from the transition drive assembly.

Wherein, an inclined surface is formed on a portion of the flat layer close to the transition drive assembly, comprising:

Providing a mask with a gradient transmittance and exposing the flat layer;

The flat layer is developed so that a portion of the flat layer close to the transition drive assembly forms an inclined surface.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

FIG1 is a schematic diagram of the structure of a microfluidic chip provided in Embodiment 1 of the present application;

FIG2 is a schematic diagram of the structure of a microfluidic chip provided in Embodiment 2 of the present application;

FIG3 is a second structural schematic diagram of a microfluidic chip provided in Embodiment 1 of the present application;

FIG4 is a schematic diagram of the structure of a microfluidic chip provided in Embodiment 3 of the present application;

FIG5 is a schematic diagram of a circuit structure of a microfluidic chip provided in Embodiment 1 of the present application;

FIG6 is a schematic cross-sectional view of a microfluidic chip provided in Embodiment 4 of the present application;

FIG7 is a schematic structural diagram of a microfluidic chip provided in Embodiment 5 of the present application;

FIG8 is a flow chart of a method for preparing a microfluidic chip provided in Embodiment 1 of the present application;

FIG9 is a flow chart of step S300 in a method for preparing a microfluidic chip according to the first embodiment of the present application;

FIG. 10 is a flow chart of step S340 in a method for preparing a microfluidic chip provided in the first embodiment of the present application.

Explanation of reference numerals: microfluidic chip 100, carrier substrate 10, covering layer 20, dielectric layer 201, hydrophobic layer 202, horizontal portion 21, first horizontal portion 211, second horizontal portion 212, deformation portion 22, groove portion 221, protrusion portion 222, thin film transistor driving component 30, first thin film transistor 301, second thin film transistor 302, gate layer 31, source layer 32, drain layer 33, active layer 34, driving electrode layer 35, extension portion 351, transition driving component 40, signal transmission layer 41, transition electrode layer 42, flat layer 50, inclined surface 51, gate insulating layer 60, first data line 71, second data line 72.

Detailed ways

The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

Reference to "embodiment" or "implementation" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiment or implementation may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above drawings are used to distinguish different objects rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

In this specification, for the sake of convenience, words and phrases indicating orientation or positional relationship such as "middle", "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like are used to illustrate the positional relationship of constituent elements with reference to the drawings. This is only for the convenience of describing this specification and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation of the present disclosure. The positional relationship of the constituent elements is appropriately changed according to the orientation of the constituent elements being described. Therefore, it is not limited to the words and phrases described in the specification and can be appropriately replaced according to the circumstances.

In this specification, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate, or the internal communication of two elements. For ordinary technicians in this field, the meanings of the above terms in this disclosure can be understood according to the circumstances.

Microfluidics is a technology that precisely controls and manipulates microscale fluids. It can integrate basic operating units such as sample preparation, reaction, separation, and detection in the biochemical analysis process onto a micrometer-scale chip, automatically completing the entire analysis process. Microfluidics has the advantages of low sample consumption, fast detection speed, simple operation, multifunctional integration, small size, and easy portability. It has great application potential in biology, chemistry, medicine, and other fields.

Among them, digital microfluidic chips generally drive the movement of droplets through the dielectric wetting effect, that is, by applying voltage to the electrode to change the contact angle of the droplet, thereby driving the droplet to move. At present, due to the mature technology and low preparation cost of thin-film transistor (TFT) backplane, microfluidic chips driven by thin-film transistors (TFTs) are increasingly valued by the market. However, the dielectric wetting effect driving voltage is generally high, sometimes reaching 60V-90V or even hundreds of volts. This voltage is difficult for existing thin-film transistor devices to bear, limiting the application of thin-film transistor technology in microfluidic chips.

Please refer to Figures 1 and 2, Figure 1 is a structural schematic diagram of a microfluidic chip provided in Embodiment 1 of the present application, and Figure 2 is a structural schematic diagram of a microfluidic chip provided in Embodiment 2 of the present application.

The present application provides a microfluidic chip 100, which is used to control the movement of microdroplets to solve the technical problem in the related art that thin film transistor driving backplane technology is difficult to apply to the microfluidic field.

The microfluidic chip 100 includes a carrier substrate 10 , a cover layer 20 , a thin film transistor driving component 30 and a transition driving component 40 .

In this embodiment, the carrier substrate 10 can be a flexible substrate. Optionally, the carrier substrate 10 can be made of any one or more of the following materials: polyimide, polyethylene terephthalate (PET), polyethylene naphthalate diformicacid glycol ester (PEN), cycloolefin polymer (COP), polycarbonate (PC), polystyrene (PS), polypropylene (PP), polytetrafluoroethylene (PTFE). In other embodiments, the carrier substrate 10 can also be a non-flexible substrate, such as glass, ceramics, etc., which is not limited in this application.

The covering layer 20 is disposed on the supporting substrate 10 , and the covering layer 20 is used for supporting the micro-droplets.

The covering layer 20 includes a dielectric layer 201 and a hydrophobic layer 202 . The hydrophobic layer 202 is disposed on a side of the dielectric layer 201 away from the supporting substrate 10 , and the hydrophobic layer 202 is used to support micro-droplets.

Furthermore, the covering layer 20 includes a horizontal portion 21 and a deformation portion 22 which are connected to each other.

The thin film transistor driving component 30 is disposed between the cover layer 20 and the carrier substrate 10, and is disposed corresponding to the horizontal portion 21 of the cover layer 20. The transition driving component 40 is disposed between the cover layer 20 and the carrier substrate 10, and is disposed corresponding to the deformation portion 22 of the cover layer 20. The transition driving component 40 cooperates with the thin film transistor driving component 30 to drive the micro-droplet to move from the horizontal portion 21 to the deformation portion 22 or from the deformation portion 22 to the horizontal portion 21.

It should be noted that the microfluidic chip 100 in the present application drives the micro-droplets to move by the dielectric wetting effect. Specifically, when a voltage is applied to the thin film transistor drive assembly 30 and the transition drive assembly 40 under the dielectric layer, the wetting characteristics between the dielectric layer and the micro-droplets attached to its surface will change. This change causes the contact angle between the micro-droplets and the hydrophobic layer surface to change, causing the micro-droplets to produce asymmetric deformation. This asymmetric deformation will produce a hydrostatic pressure difference inside the micro-liquid. When this pressure difference is large enough, the micro-droplets can be driven from a static state and move continuously along the driving direction of the electrodes in the thin film transistor drive assembly 30 or the transition drive assembly 40. In addition, the moving direction of the micro-droplets is opposite to the direction of the electric field.

Optionally, the deformation portion 22 is a groove portion 221 extending in a direction toward the carrier substrate 10 ; or, the deformation portion 22 is a protrusion portion 222 extending in a direction away from the carrier substrate 10 .

When the deformable portion 22 is a groove portion 221 , the groove portion 221 extends in a direction toward the supporting substrate 10 . In other words, the bottom of the groove portion 221 is closer to the supporting substrate 10 than the horizontal portion 21 .

The thin film transistor driving component 30 is arranged corresponding to the horizontal portion 21, and is used to drive the micro-droplets to move from the horizontal portion 21 to the groove portion 221. When the micro-droplets move from the horizontal portion 21 to the groove portion 221, part of the gravitational potential energy of the micro-droplets is converted into kinetic energy, thereby driving the micro-droplets from the horizontal portion 21 into the groove portion 221. The thin film transistor driving component 30 only needs to provide a relatively small driving voltage, so that the thin film transistor driving component 30 can be effectively used in the microfluidic chip 100. It should be noted that in this embodiment, the size of the micro-droplets is not limited, and the micro-droplets can be located at the horizontal portion 21 and partially extend to the groove portion 221.

The transition drive component 40 is arranged corresponding to the groove portion 221, and is used to drive the micro-droplets to move from the groove portion 221 to the horizontal portion 21. When the micro-droplets move from the groove portion 221 to the horizontal portion 21, it is necessary to overcome the factor of gravity, so the transition drive component 40 needs to provide a larger driving voltage. There is no need to set a thin film transistor structure in the transition drive component 40, and a larger driving voltage can be provided without affecting the normal operation of the microfluidic chip 100. In addition, because the moving direction of the micro-droplets is opposite to the direction of the electric field, when the micro-droplets need to move from the groove portion 221 to the horizontal portion 21, the voltage provided by the transition drive component 40 is a negative high voltage.

When the deformable portion 22 is a protruding portion 222 , the protruding portion 222 extends in a direction away from the supporting substrate 10 . In other words, the protruding portion 222 is away from the supporting substrate 10 relative to the horizontal portion 21 .

The thin film transistor driving component 30 is set corresponding to the horizontal part 21, and the transition driving component 40 is set corresponding to the raised part 222. When the micro droplet moves from the horizontal part 21 to the raised part 222, it is necessary to overcome the factor of gravity. Therefore, the transition driving component 40 needs to provide a larger forward driving voltage. There is no need to set a thin film transistor structure in the transition driving component 40, so a larger driving voltage can be provided without affecting the normal operation of the microfluidic chip 100.

When the micro-droplet moves from the protrusion 222 to the horizontal portion 21, part of the gravitational potential energy of the micro-droplet is converted into kinetic energy, thereby driving the micro-droplet to move from the protrusion 222 to the horizontal portion 21. The thin-film transistor driving component 30 only needs to provide a relatively small driving voltage, so that the thin-film transistor driving component 30 can be effectively used in the microfluidic chip 100. It should be noted that in this embodiment, the size of the micro-droplet is not limited, and the micro-droplet can be located on the protrusion 222 and partially extend to the horizontal portion 21.

In the microfluidic chip 100 provided in the present application, the covering layer 20 includes a connected horizontal portion 21 and a deformable portion 22, the thin film transistor driving component 30 is arranged corresponding to the horizontal portion 21 of the covering layer 20, and the transition driving component 40 is arranged corresponding to the deformable portion 22 of the covering layer 20, and the transition driving component 40 cooperates with the thin film transistor driving component 30 to drive the micro droplets to move from the horizontal portion 21 to the deformable portion 22 or from the deformable portion 22 to the horizontal portion 21. Due to the gravity of the micro droplets themselves, the thin film transistor driving component 30 only needs to provide a small driving force to move from the horizontal portion 21 to the deformable portion 22 or from the deformable portion 22 to the horizontal portion, and the thin film transistor driving component 30 only needs to provide a small driving voltage, which is convenient for the thin film transistor driving component 30 to be effectively used in the field of microfluidics.

It should be noted that, in the present application, the horizontal portion 21 includes a plurality of sub-horizontal portions arranged at intervals, the deformation portion 22 includes a plurality of sub-deformation portions arranged at intervals, and the sub-horizontal portions and the sub-deformation portions are arranged in sequence, please refer to Figures 1 and 3, Figure 3 is a structural schematic diagram 2 of a microfluidic chip provided in the first embodiment of the present application. The present application is exemplified by the number of sub-horizontal portions being 2 and the number of sub-deformation portions being 1, which should not be understood as a limitation on the present application.

Specifically, the plurality of sub-horizontal portions include a first horizontal portion 211 and a second horizontal portion 212 that are spaced apart, and the sub-deformation portion is located between the first horizontal portion 211 and the second horizontal portion 212 .

The thin film transistor driving component 30 includes a first thin film transistor 301 and a second thin film transistor 302, and the transition driving component 40 includes a sub-driving component. The first thin film transistor 301 is arranged between the first horizontal part 211 and the carrying substrate 10, and is used to cooperate with the sub-driving component to drive the micro-droplets to move from the first horizontal part 211 to the sub-deformation part. The sub-driving component is arranged between the sub-deformation part and the carrying substrate 10, and is used to cooperate with the first thin film transistor 301 or the second thin film transistor 302 to drive the micro-droplets to move from the sub-deformation part to the first horizontal part 211 or the second horizontal part 212. The second thin film transistor 302 is arranged between the second horizontal part 212 and the carrying substrate 10, and is used to cooperate with the sub-driving component to drive the micro-droplets to move from the second horizontal part 212 to the sub-deformation part.

Please refer to Figures 1 and 3. In one embodiment, the thin film transistor driving component 30 includes a source layer 32, a drain layer 33 and an active layer 34. The microfluidic chip 100 also includes a planar layer 50. The planar layer 50 is arranged between the covering layer 20 and the supporting substrate 10. The planar layer 50 covers the source layer 32, the drain layer 33 and the active layer 34.

The planar layer 50 covers the source layer 32, the drain layer 33 and the active layer 34 of the thin film transistor driving component 30, and can be used to insulate the source layer 32, the drain layer 33 and the active layer 34, and can prevent the source layer 32, the drain layer 33 and the active layer 34 from being corroded by water vapor in the external environment, thereby extending the service life of the electrode metal.

Furthermore, the thin film transistor driving component 30 further includes a driving electrode layer 35 , and the planar layer 50 further includes a via hole, and the driving electrode layer 35 is connected to the drain layer 33 through the via hole.

Furthermore, the covering layer 20 is disposed on the flat layer 50, and a portion of the flat layer 50 close to the transition drive component 40 has an inclined surface 51, and the inclined surface 51 is inclined in a direction close to the carrier substrate 10 in a direction close to the transition drive component 40, or, referring to Figure 2, the inclined surface 51 is inclined in a direction close to the carrier substrate 10 in a direction away from the transition drive component 40.

Please refer to Figures 1 and 3. In one embodiment, the thin film transistor driving component 30 also includes a gate layer 31, and the microfluidic chip 100 also includes a gate insulating layer 60. The gate insulating layer 60 is disposed on the carrier substrate 10 and covers the gate layer 31 of the thin film transistor driving component 30. The source layer 32, the drain layer 33, the active layer 34 and the transition driving component 40 are disposed on the gate insulating layer 60.

1 and 3, in one embodiment, the transition driving component 40 includes a signal transmission layer 41 and a transition electrode layer 42, and the transition electrode layer 42 is disposed on a side of the signal transmission layer 41 away from the carrier substrate 10. Specifically, the signal transmission layer 41 is used to transmit signals, and the transition electrode layer 42 is used to diffuse the signal emission.

In one embodiment, the signal transmission layer 41 and the source layer 32 can be prepared in one process, which can simplify the preparation process of the microfluidic chip 100 and improve the preparation efficiency. In addition, the transition electrode layer 42 and the drive electrode layer 35 can be prepared in one process, which further simplifies the preparation process of the microfluidic chip 100 and improves the preparation efficiency. Optionally, the transition electrode layer 42 and the drive electrode layer 35 include but are not limited to indium tin oxide (ITO). It should be noted that the signal transmission layer 41 and the transition electrode layer 42 can also be separately prepared metal layers, and this application does not limit this.

Please refer to Figures 1 to 4, Figure 4 is a schematic diagram of the structure of a microfluidic chip provided in Embodiment 3 of the present application.

In one embodiment, the driving electrode layer 35 further includes an extension portion 351, the extension portion 351 extends to the inclined surface 51 of the flat layer 50, and at least part of the extension portion 351 is disposed on the inclined surface 51 and is disposed corresponding to the deformation portion 22 of the cover layer 20. The extension portion of the driving electrode layer 35 extends to the inclined surface 51, and the micro-droplets on the inclined surface 51 can be driven, thereby improving the driving efficiency of the microfluidic chip 100 for the micro-droplets.

Please refer to FIG. 1 to FIG. 5 , FIG. 5 is a schematic diagram of a circuit structure in a microfluidic chip provided in Embodiment 1 of the present application.

In one embodiment, the microfluidic chip 100 further includes a first data line 71 and a second data line 72. The first data line 71 is connected to the source layer 32 of the thin film transistor driving component 30, and is used to transmit a first electrical signal to the source layer 32. The second data line 72 is connected to the signal transmission layer 41 of the transition driving component 40, and is used to transmit a second electrical signal to the signal transmission layer 41, wherein the voltage of the first electrical signal is less than that of the second electrical signal.

Please refer to Figure 6, which is a schematic diagram of the cross-sectional structure of a microfluidic chip provided in the fourth embodiment of the present application. In one embodiment, when the deformation portion 22 is a protrusion 222, and the height of the protrusion 222 is relatively high, the required transition electrode layer 42 can provide a relatively large driving voltage, and the transition electrode layer 42 can be divided into a plurality of sub-transition electrodes, and the heights of the plurality of sub-transition electrodes are increased in sequence, and the driving voltages of the plurality of sub-transition electrodes can also be increased as the heights increase, so as to better provide a relatively large driving voltage to the transition electrode layer 42 to better drive the micro-droplets to move.

Please refer to Figure 7, which is a schematic diagram of the structure of a microfluidic chip provided in Embodiment 5 of the present application. In one embodiment, in the horizontal direction, the shape of the transition electrode layer 42 can be a cross, and the transition electrode layer 42 is arranged between the four thin film transistor driving components 30, which can make the micro droplets move linearly in multiple directions.

Please refer to FIG. 1 to FIG. 8 , FIG. 8 is a flow chart of a method for preparing a microfluidic chip provided in Embodiment 1 of the present application.

The present application also provides a method for preparing a microfluidic chip 100, which is used to prepare the microfluidic chip 100. The method for preparing the microfluidic chip 100 includes steps S100, S300 and S500. The detailed description of steps S100, S300 and S500 is as follows.

S100: providing a carrier substrate 10 .

S300 : forming a thin film transistor driving component 30 and a transition driving component 40 on the carrier substrate 10 .

S500: forming a covering layer 20 on the thin film transistor driving component 30 and the transition driving component 40 , wherein the covering layer 20 includes a horizontal portion 21 and a deformation portion 22 connected to each other, the horizontal portion 21 is arranged corresponding to the thin film transistor driving component 30 , and the deformation portion 22 is arranged corresponding to the transition driving component 40 .

Please refer to FIG. 9 , which is a flow chart of step S300 in a method for preparing a microfluidic chip provided in the first embodiment of the present application.

In one embodiment, step S300 of forming the thin film transistor driving component 30 and the transition driving component 40 on the carrier substrate 10 includes steps S310 , S320 , S330 and S340 , and steps S310 , S320 , S330 and S340 are described in detail as follows.

S310 : forming a gate layer 31 and a gate insulating layer 60 on the carrier substrate 10 .

S320 : forming a source electrode layer 32 , a drain electrode layer 33 and an active layer 34 on the gate insulating layer 60 .

S330 : forming a planarization layer 50 .

Specifically, the planarization layer 50 is formed on the source electrode layer 32 , the drain electrode layer 33 , and the active layer 34 .

S340: An inclined surface 51 is formed on a portion of the flat layer 50 close to the transition drive assembly 40 , wherein the inclined surface 51 is inclined in a direction close to the carrier substrate 10 in a direction close to the transition drive assembly 40 , or the inclined surface 51 is inclined in a direction close to the carrier substrate 10 in a direction away from the transition drive assembly 40 .

Specifically, when the deformation portion 22 is a groove portion 221, the inclined surface 51 is inclined in a direction close to the carrier substrate 10 in a direction close to the transition drive assembly 40. When the deformation portion 22 is a protrusion 222, the inclined surface 51 is inclined in a direction close to the carrier substrate 10 in a direction away from the transition drive assembly 40.

Please refer to FIG. 10 , which is a flow chart of step S340 in a method for preparing a microfluidic chip provided in the first embodiment of the present application.

In one embodiment, step S340 of forming the inclined surface 51 on the portion of the flat layer 50 close to the transition drive assembly 40 includes steps S341 and S342 , and steps S341 and S342 are described in detail as follows.

S341 : providing a mask with a gradient transmittance and exposing the planar layer 50 .

S342 : Developing the planar layer 50 so that a portion of the planar layer 50 close to the transition drive assembly 40 forms an inclined surface 51 .

The mask has a gradient transmittance. After exposure, different positions are exposed to different exposure energies. For example, if the flat layer 50 is a positive insulating flat layer photoresist (the photoresist will be developed after exposure), the remaining film thickness of the part with high exposure energy is low after development, and the remaining film thickness of the part with low exposure energy is high after development, so as to form an inclined surface 51 in the part of the flat layer 50 close to the transition drive component 40. If the flat layer 50 is a negative photoresist, the mask is changed accordingly, which should not be understood as a limitation to the present application. Optionally, in other embodiments, the flat layer 50 can also be processed in other ways so that the flat layer 50 can form an inclined surface 51.

The above are some implementation methods of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications are also considered to be within the scope of protection of the present application.

Claims (10)

1. A microfluidic chip for controlling movement of droplets, comprising:

a carrier substrate;

The covering layer is arranged on the bearing substrate and used for bearing the micro-droplets, and comprises a horizontal part and a deformation part which are connected;

the thin film transistor driving assembly is arranged between the covering layer and the bearing substrate and corresponds to the horizontal part of the covering layer; and

The transition driving assembly is arranged between the covering layer and the bearing substrate and corresponds to the deformation part of the covering layer, and the transition driving assembly is matched with the thin film transistor driving assembly to drive the micro liquid drops to move from the horizontal part to the deformation part or from the deformation part to the horizontal part.

2. The microfluidic chip according to claim 1, wherein the deformation portion is a groove portion extending in a direction toward the carrier substrate; or the deformation part is a protruding part, and the protruding part extends along the direction deviating from the bearing substrate.

3. The microfluidic chip according to claim 2, further comprising a flat layer provided between the cover layer and the carrier substrate, the flat layer covering the source layer, the drain layer, and the active layer of the thin film transistor driving assembly, a portion of the flat layer close to the transition driving assembly having an inclined surface, and the inclined surface being inclined in a direction close to the carrier substrate in a direction close to the transition driving assembly or the inclined surface being inclined in a direction close to the carrier substrate in a direction away from the transition driving assembly.

4. The microfluidic chip of claim 3, further comprising a gate insulating layer disposed on the carrier substrate and covering the gate layer of the thin film transistor drive assembly, the source layer, the drain layer, the active layer, and the transition drive assembly being disposed on the gate insulating layer; the flat layer further comprises a via hole, and the driving electrode layer of the thin film transistor driving component is connected with the drain electrode layer through the via hole.

5. The microfluidic chip according to claim 3, wherein the transition driving assembly comprises a signal transmission layer and a transition electrode layer, the transition electrode layer is disposed on a side of the signal transmission layer facing away from the carrier substrate, the signal transmission layer and the source electrode layer of the thin film transistor driving assembly are prepared by one process, and the transition electrode layer and the driving electrode layer of the thin film transistor driving assembly are prepared by one process.

6. The microfluidic chip according to claim 5, wherein the driving electrode layer further comprises an extension portion extending onto the inclined surface of the flat layer, and at least a portion of the extension portion is disposed on the inclined surface and is disposed corresponding to the deformation portion of the cover layer.

7. The microfluidic chip of claim 3, further comprising a first data line and a second data line, the first data line connecting the source layer of the thin film transistor drive assembly, the second data line connecting the signal transmission layer of the transition drive assembly.

8. A method for preparing a microfluidic chip for preparing the microfluidic chip according to any one of claims 1 to 7, comprising:

Providing a bearing substrate;

Forming a thin film transistor driving assembly and a transition driving assembly on the bearing substrate;

And forming a covering layer on the thin film transistor driving assembly and the transition driving assembly, wherein the covering layer comprises a horizontal part and a deformation part which are connected, the horizontal part is arranged corresponding to the thin film transistor driving assembly, and the deformation part is arranged corresponding to the transition driving assembly.

9. The method of manufacturing a microfluidic chip according to claim 8, further comprising:

forming a flat layer;

And forming an inclined surface on a part of the flat layer, which is close to the transition driving assembly, wherein the inclined surface is inclined in a direction close to the bearing substrate in a direction close to the transition driving assembly, or the inclined surface is inclined in a direction close to the bearing substrate in a direction away from the transition driving assembly.

10. The method of manufacturing a microfluidic chip according to claim 9, wherein forming an inclined surface at a portion of the flat layer adjacent to the transition driving assembly comprises:

Providing a mask plate with gradual transmittance and exposing the flat layer;

the flat layer is developed so that a portion of the flat layer adjacent to the transition drive assembly forms an inclined surface.