KR102706712B1 - Microfluidic apparatus and method for manufacturing the same - Google Patents

Abstract

A microfluidic device according to an embodiment of the present invention and a manufacturing method therefor are provided. A microfluidic device according to an embodiment of the present invention includes: a first substrate on which an electrode array formed of a plurality of electrode lines is formed; a photoresist layer on which an inlet for injecting a fluid, an outlet for discharging the fluid, and a flow channel fluidly connected to the inlet and the outlet so that the fluid flows are formed; and a second substrate on which a first hole through which the fluid is injected corresponding to the inlet and a second hole through which the fluid is discharged corresponding to the outlet are formed on the photoresist layer, wherein a plurality of gas discharge lines are formed in a remaining area of the photoresist layer excluding an area where the inlet, the outlet, and the flow channel are formed.

Description

{MICROFLUIDIC APPARATUS AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to a microfluidic device and a method for manufacturing the same.

Lab-on-a-chip (LOC) technology is in the spotlight. Lab-on-a-chip technology is a representative example of NT, IT, and BT convergence technology, and refers to technology that performs all preprocessing and analysis steps of samples, such as dilution, mixing, reaction, separation, and quantification, on a single chip using technologies such as MEMS and NEMS.

Microfluidic devices using lab-on-a-chip technology such as this one are manufactured in a form in which a number of units necessary for analysis are equipped on a small chip of a few cm2 in size made of glass, silicon or plastic so that they can analyze and diagnose the flow of a fluid sample flowing through a reaction channel or the reaction between a fluid sample and a reagent supplied to the reaction channel, as well as perform various stages of processing and manipulation related to the control of the fluid sample on a single chip.

However, since these microfluidic devices are made up of multiple layers of glass, silicon, or plastic, adhesion may not occur well due to different materials, and the thickness of the bonded layers may increase, which may cause defects during the subsequent dicing process.

Accordingly, a microfluidic device and a method for manufacturing the same are required to minimize dicing defects while increasing adhesive strength when bonding multiple layers made of various materials.

The inventors of the present invention have recognized that when a substrate formed of glass is bonded to a layer in which a euro channel is formed, if the bonding strength decreases, the layers are either completely separated or damaged during a subsequent dicing process.

In addition, the inventors of the present invention recognized that when bonding a plurality of layers made of different materials and dicing the bonded plurality of layers, a defect may be caused in the dicing device due to the thickness of the layers, and the bonded layers may be damaged.

The problem to be solved by the present invention is to provide a microfluidic device and a manufacturing method therefor for minimizing breakage defects in a dicing process while increasing the adhesive strength of layers made of different materials.

The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

In order to solve the above-described problem, a microfluidic device according to an embodiment of the present invention and a method for manufacturing the same are provided. The microfluidic device according to an embodiment of the present invention may include a first substrate on which an electrode array composed of a plurality of electrode lines is formed; a photoresist layer on which an inlet for injecting a fluid, an outlet for discharging the fluid, and a flow channel fluidly connected to the inlet and the outlet so that the fluid flows are formed on the first substrate; and a second substrate on which a first hole for injecting a fluid corresponding to the inlet and a second hole for discharging the fluid corresponding to the outlet are formed on the photoresist layer.

According to an embodiment of the present invention, a photoresist layer may have a plurality of gas discharge lines formed in a region other than a region where an inlet, outlet, and euro channel are formed.

The first substrate according to an embodiment of the present invention may be made of silicon.

The photoresist layer according to an embodiment of the present invention may be formed of an adhesive organic material.

The inlet and outlet according to an embodiment of the present invention are formed in a cylindrical shape, and the diameter of each of the inlet and outlet can be configured to be wider than the width of the euro channel.

According to an embodiment of the present invention, a photoresist layer may have an open region formed such that a portion of the upper surface of an edge portion of the first substrate is open.

According to an embodiment of the present invention, a second substrate may have a second open area formed such that a portion of an upper surface of an edge portion of the first substrate is opened corresponding to the first open area of the photoresist layer.

An electrode array according to an embodiment of the present invention may further include a plurality of dummy lines corresponding to each of a plurality of electrode lines.

According to an embodiment of the present invention, the method comprises the steps of forming an electrode array composed of a plurality of electrode lines on a first substrate, bonding a photoresist layer on the first substrate on which the electrode array is formed, etching the photoresist layer using a first mask pattern to form an inlet for injecting a fluid, an outlet for discharging the fluid, and a flow channel fluidly connected to the inlet and the outlet so that the fluid can flow, and bonding a second substrate that has been etched through a second mask pattern on the etched photoresist layer.

Using the first mask pattern according to an embodiment of the present invention, a plurality of gas discharge lines can be further formed in an area other than an area where an inlet, outlet, and euro channel are formed.

Specific details of other embodiments are included in the detailed description and drawings.

According to the present invention, since a gas discharge line is formed in a photoresist layer, air bubbles generated from the photoresist layer when bonding the photoresist layer and a second substrate are discharged to the outside through the gas discharge line, thereby strengthening the adhesive strength between layers made of different materials, thereby minimizing the occurrence of errors such as breakage or damage during a dicing process.

In addition, the present invention minimizes the dicing line of the photoresist layer and the second substrate by forming each side of the photoresist layer and the second substrate concavely inward from the side so as to open a portion of the upper surface of the edge portion of the first substrate, thereby minimizing the occurrence of errors such as breaking or damage during the dicing process and enabling stable and smooth dicing.

The effects according to the present invention are not limited to those exemplified above, and more diverse effects are included in this specification.

FIG. 1 is a schematic perspective view illustrating a microfluidic device according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view illustrating a microfluidic device according to an embodiment of the present invention.
FIG. 3 is a cross-sectional view taken along line A-A' shown in FIG. 1 according to an embodiment of the present invention.
FIG. 4 is an exemplary diagram of a first mask pattern for forming a photoresist layer according to an embodiment of the present invention.
FIG. 5 is an exemplary diagram of a second mask pattern for forming a second substrate according to an embodiment of the present invention.
FIGS. 6A, 6B, 6C, 6D, and 6E are schematic cross-sectional views illustrating a method for manufacturing a microfluidic device according to an embodiment of the present invention.

The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and these embodiments are provided only to make the disclosure of the present invention complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. With respect to the description of the drawings, similar reference numerals may be used for similar components.

In this document, the expressions "have," "can have," "include," or "may include" indicate the presence of a given feature (e.g., a numerical value, function, operation, or component such as a part), but do not exclude the presence of additional features.

In this document, the expressions "A or B," "at least one of A and/or B," or "one or more of A or/and B" can include all possible combinations of the items listed together. For example, "A or B," "at least one of A and B," or "at least one of A or B" can all refer to cases where (1) at least one A is included, (2) at least one B is included, or (3) both at least one A and at least one B are included.

The expressions "first," "second," "first," or "second," etc., used in this document can describe various components, regardless of order and/or importance, and are only used to distinguish one component from another, but do not limit the components. For example, a first user device and a second user device can represent different user devices, regardless of order or importance. For example, without departing from the scope of the rights set forth in this document, a first component can be named a second component, and similarly, a second component can also be renamed as a first component.

When it is stated that a component (e.g., a first component) is "(operatively or communicatively) coupled with/to" or "connected to" another component (e.g., a second component), it should be understood that the component can be directly coupled to the other component, or can be connected via another component (e.g., a third component). Conversely, when it is stated that a component (e.g., a first component) is "directly coupled to" or "directly connected to" another component (e.g., a second component), it should be understood that no other component (e.g., a third component) exists between the component and the other component.

The expression "configured to" as used herein can be used interchangeably with, for example, "suitable for," "having the capacity to," "designed to," "adapted to," "made to," or "capable of." The term "configured to" does not necessarily mean something that is "specifically designed to" in terms of hardware. Instead, in some contexts, the expression "a device configured to" can mean that the device is "capable of" doing something in conjunction with other devices or components. For example, the phrase "a processor configured (or set) to perform A, B, and C" can mean a dedicated processor (e.g., an embedded processor) to perform those operations, or a generic-purpose processor (e.g., a CPU or an application processor) that can perform those operations by executing one or more software programs stored in a memory device.

The terms used in this document are only used to describe specific embodiments and may not be intended to limit the scope of other embodiments. The singular expression may include the plural expression unless the context clearly indicates otherwise. The terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by a person of ordinary skill in the art described in this document. Among the terms used in this document, terms defined in general dictionaries may be interpreted as having the same or similar meaning in the context of the related technology, and shall not be interpreted in an ideal or excessively formal meaning unless explicitly defined in this document. In some cases, even if a term is defined in this document, it cannot be interpreted to exclude the embodiments of this document.

The individual features of the various embodiments of the present invention may be partially or wholly combined or combined with each other, and as can be fully understood by those skilled in the art, various technical connections and operations are possible, and each embodiment may be implemented independently of each other or may be implemented together in a related relationship.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings.

FIG. 1 is a schematic perspective view for explaining a microfluidic device according to an embodiment of the present invention, FIG. 2 is an exploded perspective view for explaining a microfluidic device according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along line A-A' shown in FIG. 1 according to an embodiment of the present invention.

Referring to FIGS. 1 to 3, a microfluidic device (1000) includes a first substrate (1100) on which an electrode array (1110) is formed, a photoresist layer (1200) formed on an upper surface of the substrate (1100), and a second substrate (1300) formed on an upper surface of the photoresist layer (1200).

An electrode array (1110) composed of a plurality of electrode lines is formed on the first substrate (1100). In particular, the first substrate (1100) may be made of silicon, amorphous silicon, single crystal silicon, silicon carbide, etc., but is not limited thereto. In various embodiments, the first substrate (1100) may be coated with an insulating layer depending on electrical characteristics.

The electrode array (1110) is made of a metal material, and the metal material may be a material composed of an element named as a metal in the chemical periodic table, such as Au, Mg, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Al, Zr, Nb, Mo, Ru, Ag, Sn, etc. The electrode array (1110) may be formed of any one of the aforementioned metal materials, or may be formed of a metal mixture in which at least one or more of the aforementioned metal materials are mixed.

In various embodiments, the electrode array (1100) may further include a plurality of dummy lines corresponding to each electrode line in addition to the electrode lines. For example, a plurality of dummy lines may be arranged on both sides centered on each metal line. Through these dummy lines, precise pattern formation of the electrode lines is possible.

The photoresist layer (1200) is formed on the first substrate (1100) and may be made of an adhesive organic material. In particular, the photoresist layer (1200) has an inlet (1210) for injecting a fluid, an outlet (1220) for discharging the fluid, and a flow channel (1230) fluidically connected to the inlet (1210) and the outlet (1220) so that the fluid flows.

The inlet (1210) may be formed to correspond to the position of the first hole (1310) of the second substrate (1300) described later, and the outlet (1220) may be formed to correspond to the position of the second hole (1320) of the second substrate (1300). Accordingly, the microfluid injected through the first hole (1310) may be inserted into the flow channel (1230) through the inlet (1210) and flow, and the microfluid flowing through the flow channel (1230) may be discharged out through the outlet (1220) and the second hole (1320).

Specifically, the inlet (1210) and the outlet (1220) are formed in a cylindrical shape, and a flow channel (1230) may be formed between the inlet (1210) and the outlet (1230) to connect the inlet (1210) and the outlet (1230) to each other. The flow channel (12330) connects one side of the inlet (1210) and one side of the outlet (1220) facing the one side, and may have a width narrower than the diameters of the inlet (1210) and the outlet (1220). The inlet (1210), the outlet (1220), and the flow channel (1230) may be formed to penetrate the photoresist layer (1200).

In particular, the euro channel (1230) may be formed at a position corresponding to the electrode array (1110) of the first substrate (1100). When a fluid containing particles flows over the electrode array (1110) through the euro channel (1230), a potential difference is generated each time the fluid passes the electrode array (1110), thereby enabling detection of the passage of particles.

In addition, the photoresist layer (1200) may have a plurality of gas discharge lines (1240) formed in the remaining area except for the area where the flow channel is formed. When a second substrate (1300) made of glass is bonded to the photoresist layer (1200), bubbles may be generated between the photoresist layer (1200) and the second substrate (1300), and these bubbles may penetrate into the flow channel (1230). Therefore, in order to prevent the generated bubbles from penetrating into the flow channel, a plurality of gas discharge lines (1240) intersecting straight lines may be formed in the photoresist layer (1200). These gas discharge lines (1240) are connected to the sidewall of the photoresist layer (1200) so that the bubbles may be discharged to the outside.

In this way, by discharging air bubbles generated in the photoresist layer (1200) during bonding with the second substrate (1300) through the gas discharge line (1240), the adhesive strength between the photoresist layer (1200) and the second substrate (1300) can be improved while minimizing the error rate.

In addition, a first open area may be formed on each side of the photoresist layer (1200) so that a portion of the upper surface (1120) of the edge portion of the first substrate (1100) is opened. For example, a portion of the side surface of the photoresist layer (1200) may be formed concavely inward from the side surface, thereby opening a portion of the upper surface (1120) of the edge portion of the first substrate (1100). Through this first open area, a contact pad is exposed, so that a voltage can be applied to the electrode for electrical measurement.

Meanwhile, the second substrate (1300) may be made of an organic material such as glass, plastic, and PDMS (Polydimethylsiloxane). In particular, the second substrate (1300) may be formed with a first hole (1310) that can inject fluid into the inlet (1210) and a second hole (1320) that discharges fluid discharged from the outlet (1220). The first hole (1310) is formed in a cylindrical shape penetrating the second substrate (1300) corresponding to the position of the inlet (1210) of the photoresist layer (1200), and the second hole (1320) is formed in a cylindrical shape penetrating the second substrate (1300) corresponding to the position of the outlet (1220) of the photoresist layer (1200).

The second substrate (1300) may also be formed with a second open area so that each side surface of a portion (120) of an edge portion of the first substrate (1100) is open. For example, a portion of a side surface of the second substrate (1300) may be formed to be concave inward from the side surface, thereby opening a portion (1120) of an upper surface of an edge portion of the first substrate (1100). The positions and sizes of the first open area and the second open area described above may be identical to each other.

These open areas expose the contact pads, allowing voltage to be applied to the electrodes for electrical measurements.

In this way, the contact pads are exposed by the side structures of the photoresist layer (1200) and the second substrate (1300), so that a voltage can be applied to the electrode layer (1110) of the substrate (1100) for electrical measurement.

Below, the first mask pattern for forming the above-described photoresist layer (1200) and the second mask pattern for forming the second substrate (1300) will be described.

FIG. 4 is an exemplary diagram of a first mask pattern for forming a photoresist layer according to an embodiment of the present invention, and FIG. 5 is an exemplary diagram of a second mask pattern for forming a second substrate according to an embodiment of the present invention.

Referring to FIGS. 1 to 4, the first mask pattern (400) may include a first pattern region (410) for forming an inlet (1210), an outlet (1220), and a flow channel (1230) of a photoresist layer (1200), a second pattern region (420) for forming a plurality of gas discharge lines (1240), and a third pattern region (430) for opening a portion of an upper surface of an edge portion of a substrate (1100). The above-described photoresist layer (1200) may be formed using the first mask pattern (400).

In addition, the first mask pattern (400) may further include a dicing line pattern (440) for dicing. By the dicing line pattern (440), the photoresist layer (1200) may be partially etched to a preset thickness during an etching process for the photoresist layer (1200). Since the length of the dicing line pattern (440) is minimized by the third pattern area (430), the area for dicing is also minimized, thereby enabling stable dicing.

Referring to FIGS. 1 to 3 and 5, the second mask pattern (500) may include a fifth pattern region (510) for forming a first hole (1310) of the second substrate (1300), a sixth pattern region (520) for forming a second hole (1320), and a seventh pattern region (530) for opening a portion of an upper surface of an edge portion of the substrate (1100).

In addition, the second mask pattern (500) may further include a dicing line pattern (540) for dicing. By this dicing line pattern (540), the second substrate (1300) may be partially etched to a preset thickness during an etching process for the second substrate (1300). Since the length of the dicing line pattern (540) is minimized by this seventh pattern region (530), the region for dicing is also minimized, thereby enabling stable dicing.

Hereinafter, a method for manufacturing a microfluidic device will be described in detail with reference to FIGS. 6a, 6b, 6c, 6d, and 6e.

FIGS. 6A, 6B, 6C, 6D, and 6E are schematic cross-sectional views illustrating a method for manufacturing a microfluidic device according to an embodiment of the present invention.

Referring to FIG. 6a, an electrode array (1110) is formed on a first substrate (1100). The electrode array (1110) may be formed, for example, through lithography, metal deposition, and patterning steps. Furthermore, when the first substrate (1100) is silicon, an insulating film may be formed on an upper surface of the first substrate (1100). The insulating film may be an oxide or nitride layer.

Referring to FIG. 6b, a photoresist layer (1200) is formed on a first substrate (1100). The formation of the photoresist layer (1200) can be performed in a manner in which the photoresist layer (1200) is bonded on a first substrate (1100) on which an electrode array (1110) is formed.

Referring to FIG. 6c, a first mask pattern (400) described in FIG. 4 is formed on a photoresist layer (1200), and as shown in FIG. 6d, the photoresist layer (1200) is patterned using the first mask pattern (400) to form an inlet (1210), an outlet (1220), a flow channel (1230), and a gas exhaust line (1240). Furthermore, through this patterning process, a portion of each side surface of the photoresist layer (1200) may be removed so that a portion of the upper surface (1120) of each edge portion of the first substrate (1100) is exposed (or opened). The patterning of the photoresist layer (1200) may be implemented using a general photoresist method.

Referring to FIG. 6e, a second substrate (1300) is formed on a photoresist layer (1200). The formation of the second substrate (1300) may be performed in such a manner that the second substrate (1300) is bonded on a photoresist layer (1200) in which an inlet (1210), an outlet (1220), a flow channel (1230), and a gas exhaust line (1240) are formed. Here, the second substrate (1300) may be formed with a first hole (1310) and a second hole (1320) through an etching process using the second mask pattern (500) described in FIG. 5, and a portion of each side surface of the second substrate (1300) may be removed so that a portion of the upper surface (1120) of an edge portion of the first substrate (1100) is exposed (or opened). For example, the etching process for the second substrate (1300) may use a sand blast process.

When a second substrate (1300) having a first hole (1310) and a second hole (1320) formed on the upper surface of a photoresist layer (1200) having a gas discharge line (1240) formed in this way is bonded, air bubbles generated from the photoresist layer (1200) are discharged through the gas discharge line (1240) formed in the photoresist layer (1200), thereby strengthening the adhesive strength between layers made of different materials (the first substrate, the photoresist layer (1200), and the second substrate (1300)), thereby minimizing the occurrence of errors such as breakage or damage during the dicing process.

In addition, since each side of the photoresist layer (1200) and the second substrate (1300) is formed concavely inward from the side to open a portion of the upper surface of the edge portion of the first substrate (1100), the dicing line of the photoresist layer (1200) and the second substrate (1300) is minimized, thereby minimizing the occurrence of errors such as breaking or damage during the dicing process, and enabling stable and smooth dicing.

Although the embodiments of the present invention have been described in more detail with reference to the attached drawings, the present invention is not necessarily limited to these embodiments, and various modifications may be made without departing from the technical idea of the present invention. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain it, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are exemplary in all aspects and not restrictive. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

1000: Microfluidic Devices
1100: 1st board
1100: Electrode Array
1200: Photoresist layer
1210: Inlet
1220: Outlet
1230: Euro Channel
1300: Second substrate
1310: Hall 1
1320: 2nd hole

Claims (8)

A first substrate on which an electrode array composed of a plurality of electrode lines is formed;
A photoresist layer having an inlet for injecting a fluid onto the first substrate, an outlet for discharging the fluid, and a flow channel fluidly connected to the inlet and the outlet so that the fluid flows; and
A second substrate is formed on the upper surface of the photoresist layer, in which a first hole through which the fluid is injected corresponding to the inlet and a second hole through which the fluid is discharged corresponding to the outlet are formed,
A microfluidic device in which the photoresist layer forms a plurality of gas discharge lines in a form in which a plurality of straight lines intersect in a region other than the region where the inlet, the outlet, and the flow channel are formed so that air bubbles generated when the second substrate is bonded to the upper surface of the photoresist layer can be discharged. In the first paragraph,
The above first substrate is a microfluidic device made of silicon. In the first paragraph,
A microfluidic device, wherein the photoresist layer is made of an adhesive organic material. In the first paragraph,
The above inlet and the above outlet are formed in a cylindrical shape,
A microfluidic device, wherein each of the inlet and the outlet has a diameter wider than the width of the euro channel. In the first paragraph, the photoresist layer,
A microfluidic device, wherein a first open area is formed so that a portion of an upper surface of an edge portion of the first substrate is open. In the fifth paragraph, the second substrate,
A microfluidic device, wherein a second open area is formed so that a portion of an upper surface of an edge portion of the first substrate is opened corresponding to the first open area of the photoresist layer. In the first paragraph, the electrode array,
A microfluidic device further comprising a plurality of dummy lines corresponding to each of the plurality of electrode lines. A step of forming an electrode array composed of a plurality of electrode lines on a first substrate;
A step of bonding a photoresist layer on the first substrate on which the electrode array is formed;
A step of etching the photoresist layer using a first mask pattern to form an inlet for injecting a fluid, an outlet for discharging the fluid, and a flow channel fluidly connected to the inlet and the outlet so that the fluid flows;
A step of bonding a second substrate etched through a second mask pattern to the upper surface of the etched photoresist layer,
The step of etching the above photoresist layer is:
A method for manufacturing a microfluidic device, wherein a plurality of gas discharge lines are further formed in a form in which a plurality of straight lines intersect in a remaining area excluding an area where the inlet, the outlet, and the flow channel are formed using the first mask pattern so that air bubbles generated when the second substrate is adhered to the upper surface of the photoresist layer can be discharged.

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