KR20170093548A - Biosensor and method for manufacturing thereof - Google Patents

Abstract

The present invention relates to a biosensor and a manufacturing method thereof. By manufacturing a sensor based on a field effect transistor (FET) using a printed circuit board (PCB); a packaging process is not required and a semiconductor process to manufacture the sensor is simplified. The biosensor comprises: a printed circuit board (PCB) formed with a circuit pattern; a source electrode, a gate electrode, and a drain electrode formed with a predetermined space from each other on the printed circuit board; a first insulating film formed on the gate electrode; and a detection film laminated to connect the source electrode and the drain electrode on the printed circuit board formed with the first insulating film.

Description

TECHNICAL FIELD [0001] The present invention relates to a biosensor and a method of manufacturing the same,

The present invention relates to a biosensor, and more particularly, to a biosensor using a printed circuit board (PCB) to fabricate a field-effect transistor (FET) -based sensor and a method of manufacturing the same.

A biosensor is a sensor that uses biological elements to detect information from a measurement object or imitates a biological system and converts it into a recognizable signal such as color, fluorescence, or electrical signal.

In recent years, research and development using biosensors have been progressing more rapidly than precision analyzers, with emphasis on promptness and convenience in the field of detecting chemical or biological molecules. Particularly, biosensors using electrical signals are fast in signal conversion and easy to miniaturize There are many advantages and many are applied.

As a typical biosensor using an electrical signal, there is a field effect transistor (FET) biosensor. Since it is manufactured using a semiconductor process, it is easy to integrate integrated circuits and MEMS, There is an advantage.

1 is a schematic diagram schematically showing a conventional field-effect transistor-based biosensor.

Referring to FIG. 1, a conventional field effect transistor-based biosensor 10 is configured based on a wafer substrate.

That is, the insulating layer 12 and the sensing film 13 are formed on the wafer substrate 11 such as silicon or glass, and the source electrode 14 and the drain electrode 15 are formed on both sides of the sensing film 13 Are arranged at a predetermined interval. When a voltage is applied between the source electrode 14 and the drain electrode 15, the sensing film 13 between the two electrodes acts as a channel through which current flows, and selectively recognizes a specific molecule in the sensing film 13 Charged particles generated between the source electrode 14 and the drain electrode 15 move along the electric field direction and a current signal is output from the source electrode 14 or the drain electrode 15.

The intensity of the output current signal is proportional to the density of the charged particles. When a voltage is applied to a gate electrode (not shown) formed under the channel through the insulating layer 12, the density of charged particles existing in the channel changes , The voltage of the gate electrode (not shown) can be controlled to output a current signal of a size easy to detect. For example, in FIG. 1, it is possible to control the wafer substrate 11 to function as a gate electrode by applying a voltage of the opposite polarity to the voltage applied to the source electrode 14 on the wafer substrate 11.

However, the conventional field effect transistor-based biosensor 10 has a disadvantage in that a basic manufacturing process ratio increases because a wafer substrate is used.

In addition, the conventional field effect transistor-based biosensor 10 may include a dicing process for cutting a wafer in order to separate chips into individual chips, a packaging process for mounting on a PCB substrate, There is a problem that the defect rate due to these processes is increased.

Accordingly, the applicant of the present invention has proposed the present invention in order to solve the above-mentioned problems. As a prior art document related thereto, Korean Patent No. 10-1130947 entitled " Carbon Nanotube- Sensor and manufacturing method thereof, registered on March 20, 2012).

The present invention aims to provide a biosensor in which a packaging process is not required and a semiconductor process for manufacturing a sensor is simplified by manufacturing a field-effect transistor (FET) -based sensor using a printed circuit board (PCB) have.

According to an aspect of the present invention, there is provided a printed circuit board (PCB) substrate on which circuit patterns are formed. A source electrode, a gate electrode, and a drain electrode formed on the printed circuit board at predetermined intervals; A first insulating layer formed on the gate electrode; And a sensing layer laminated on the printed circuit board on which the first insulating layer is formed so that the source electrode and the drain electrode are connected to each other.

Wherein the sensing film of the biosensor is formed of carbon nanotubes or graphenes and is stacked on the upper surface of the printed circuit board corresponding to the source electrode, the gate electrode and the drain electrode, and the upper surface of the gate electrode, And overlaps the upper surface of the source electrode and the drain electrode.

The biosensor further includes a second insulating layer formed to cover at least one of the source electrode and the drain electrode so as to prevent short-circuiting between the source electrode and the drain electrode.

The biosensor may further include: first and second electrode terminals formed on the printed circuit board to connect to a power source; A third electrode terminal formed on the printed circuit board to connect to the current detection unit; The first electrode terminal electrically connects the first and second electrode terminals to the source electrode and the gate electrode, and the third electrode terminal includes signal lines formed on a lower surface of the printed circuit board to electrically connect the drain electrode and the drain electrode .

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, including: stacking a conductive material for forming an electrode on a PCB substrate on which a circuit pattern is formed; Forming a source electrode, a gate electrode, and a drain electrode on the substrate by patterning the conductive material; Forming a first insulating film on the gate electrode; And forming a sensing film so that the source electrode and the drain electrode are connected to each other on the printed circuit board on which the first insulating film is formed.

The method of fabricating the biosensor may further include forming a second insulating layer so as to cover at least one of the source electrode and the drain electrode to prevent a short circuit between the source electrode and the drain electrode.

In the method for fabricating a biosensor, the forming of the sensing layer may include forming a sensing layer of carbon nanotubes or graphene on the sensing layer, An upper surface and an upper surface of the gate electrode, and may be formed to overlap the upper surface of the source electrode and the drain electrode.

In the method of manufacturing the biosensor, the step of forming the first insulating film and the step of forming the sensing film may be formed using an ink-jet printing method.

In the method of fabricating the biosensor, forming first and second electrode terminals on the printed circuit board to connect to a power source unit; Forming a third electrode terminal on the printed circuit board to connect to the current detection unit; Forming the signal lines on the lower surface of the printed circuit board so as to electrically connect the first and second electrode terminals to the source electrode and the gate electrode and electrically connect the third electrode terminal to the drain electrode, .

According to the present invention, by manufacturing a field-effect transistor (FET) -based sensor using a substrate on which a circuit pattern is formed, that is, a printed circuit board (PCB), a packaging process is unnecessary and a semiconductor process for manufacturing a sensor is simplified, Can be saved.

In addition, defects caused by the packaging process can be solved. Further, since the source electrode, the gate electrode, and the drain electrode constituting the field effect transistor (FET) are implemented on the same plane, The bonding process can be reduced.

In addition, an additional insulating film is formed on at least one of the source electrode and the drain electrode, so that the occurrence of a short circuit between the source electrode and the drain electrode can be eliminated.

1 is a schematic diagram schematically illustrating a conventional field effect transistor-based biosensor.
2 is a cross-sectional view illustrating a field-effect transistor-based biosensor according to an embodiment of the present invention.
FIGS. 3 to 7 are views for explaining a method of manufacturing a field effect transistor-based biosensor according to an embodiment of the present invention.
8 is a plan view of a biosensor in which electrodes of a biosensor are connected to an electrode terminal on a PCB substrate according to an embodiment of the present invention.

It is noted that the technical terms used herein are used only to describe specific embodiments and are not intended to limit the invention. Also, the technical terms used herein should be interpreted in a sense that is generally understood by those skilled in the art to which the present invention belongs, unless otherwise defined in this specification, and it should be understood that an overly comprehensive It should not be construed as a meaning or an overly reduced meaning.

Also, the singular forms "as used herein include plural referents unless the context clearly dictates otherwise. In the present application, the term "comprising" or "comprising" or the like should not be construed as necessarily including the various elements or steps described in the specification, Or may be further comprised of additional components or steps.

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

For reference, the biosensor according to the embodiment of the present invention implements the components, which perform the same functions as the components of the existing wafer-based biosensor, directly on the printed circuit board, thereby simplifying the semiconductor process, And to provide a configuration capable of eliminating defects that occur.

2 is a cross-sectional view illustrating a field-effect transistor-based biosensor according to an embodiment of the present invention.

2, a biosensor 100 according to an embodiment of the present invention includes a printed circuit board 110 (hereinafter referred to as a PCB substrate) having a circuit pattern formed thereon, A patterned source electrode S 121, a gate electrode G 123 and a drain electrode D 125, a first insulating layer 130 formed on the gate electrode 123, a source electrode 121, And a sensing film 140 stacked on the PCB substrate 110 such that the electrodes 125 are connected to each other. The second insulating layer 150 may be formed to cover at least one of the source electrode 121 and the drain electrode 125 to eliminate a short circuit between the source electrode 121 and the drain electrode 125 when biological or chemical molecules are detected. As shown in FIG.

Such a biosensor 100 is manufactured through the manufacturing process of FIGS. 3 to 7 described below.

Referring to FIG. 3, a PCB substrate 110 on which a circuit pattern is formed is prepared, and a conductive material 120 for forming a source electrode, a gate electrode, and a drain electrode is deposited on the PCB substrate 110.

The PCB substrate 110 refers to a substrate having a plurality of wire bonding portions (for example, a band of conductive metal) provided on an insulating substrate.

Referring to FIG. 4, a conductive material 120 is patterned to form a source electrode 121, a gate electrode 123, and a drain electrode 125 on a PCB substrate 110.

The source electrode 121, the gate electrode 123 and the drain electrode 125 are formed on the PCB substrate 110 at a predetermined distance from each other and are generally formed into a patterned shape through a photoresist process. no.

The source electrode 121, the gate electrode 123 and the drain electrode 125 are made of at least one metal selected from the group consisting of gold (Au), silver (Ag), titanium (Ti) Lt; / RTI > For example, it may be formed of gold (Au) having high conductivity, but titanium (Ti) may be mixed with the outer substrate 110 to enhance adsorption thereof.

5, a first insulating layer 130 is formed on a PCB substrate 110 on which a source electrode 121, a gate electrode 123, and a drain electrode 125 are formed to insulate the gate electrode 123. Referring to FIG. do.

The first insulating film 130 is formed to surround the upper surface and side surfaces of the gate electrode 123. The first insulating layer 130 may be formed of a silicon dioxide (SiO 2) -based insulating material.

As shown in the figure, in the step of forming the first insulating layer 130 only on the gate electrode 123, which is a part of the PCB substrate 110, the first insulating layer 130 may be formed using an inkjet printing method or a dipping method. However, the present invention is not limited thereto, and may be formed using a photoresist process and a partial etching process. In the case of the ink-jet printing method, the first insulating layer 130 may be formed on the gate electrode 123 as shown in FIG. 5 without being formed as a thin film, but may be convexly coated. However, it is possible to adjust the amount and speed of the ink jetted from the inkjet to have a thickness that does not greatly affect the performance of the biosensor and the resistance of the sensing film.

6, a sensing layer 140 is formed on the PCB substrate 110 such that the source electrode 121 and the drain electrode 125 are connected to each other in a state where the first insulating layer 130 is formed. The sensing film 140 formed between the source electrode 121 and the drain electrode 125 becomes a channel in which charge carriers generated between the source electrode 121 and the drain electrode 125 move along the electric field direction.

The sensing layer 140 may be formed of carbon nanotube (CNT) or graphene. Graphene is a thin layer of carbon that is thinner than 0.2 nanometers (nm) in thickness, but has the advantage of being harder than steel and better electrically than copper. Carbon nanotubes are tubes made of one layer of carbon, with six hexagons of carbon connected together to form a tubular shape with only a few nanometers of tube diameter. Carbon nanotubes have the same electrical conductivity as copper and have the same thermal conductivity as natural diamond.

6, the sensing film 140 is formed on the upper surface of the PCB substrate 110 corresponding to the space between the source electrode 121 and the gate electrode 123 and the drain electrode 125. In this case, And the upper surface of the gate electrode 123 on which the first insulating layer 130 is formed and overlaps the upper surface of the source electrode 121 and the drain electrode 123 partially or entirely.

As a method of forming the sensing layer 140, an inkjet printing method, a dipping method, or the like may be used in the same manner as the method of forming the first insulating layer 130.

For example, when a surfactant and a dispersion solution are added to and dispersed in a solid carbon nanotube (CNT), and the liquid carbon nanotube ink having been dispersed is injected into an inkjet, You can print while adjusting. Alternatively, the dipping process can be performed using a roll of the carbon nanotube ink in the liquid state in which the dispersion is completed. The carbon nanotube ink applied by these processes is adsorbed on the upper surface of the PCB substrate 110 and the upper surfaces of the electrodes 121, 123, and 125 by the carbon nanotube particles, Thereby forming a film 140.

When the particles are adsorbed on the surfaces of the carbon nanotubes (CNTs) by adsorbing the antibodies, the sensing material 140 is immobilized on the surfaces of the target substances (for example, IgF, IgM , IgG, hemoglobin, etc.) is adsorbed on the antibody, the resistance of the sensing membrane 140 changes. By detecting such a change, it becomes possible to detect a molecule as a target substance.

Next, referring to FIG. 7, the upper surface of the source electrode 121, more specifically, the exposed surface of the source electrode 121 and the sensing film 140 located on the upper surface of the source electrode 121 The second insulating film 150 can be formed.

The second insulating layer 150 is formed to prevent short-circuiting between the source electrode 121 and the drain electrode 125 when biological or chemical molecules are detected. In FIG. 7, the second insulating layer 150 is formed only on the source electrode 121, But may be formed on the drain electrode 125 without limitation.

Alternatively, the second insulating layer 150 may be formed to cover both the source electrode 121 and the drain electrode 125.

The second insulating layer 150 may be formed of an insulating material such as silicon dioxide (SiO 2) in the same manner as the first insulating layer 130, and may be formed using an inkjet printing method. Or may be formed using a dipping method.

The biosensor 100 thus formed is formed by forming a source electrode 121, a gate electrode 123 and a drain electrode 125 on a same plane on a PCB substrate 110 and forming a sensing film 140 thereon Thereby making it possible to simplify the manufacturing process. .

In addition, since the biosensor 100 according to the embodiment of the present invention performs a semiconductor process directly on the PCB substrate 110, the operation for wire bonding between the biosensor 100 and the PCB substrate 110 during the packaging process And direct connection between the electrode terminals on the PCB substrate 110 and the electrodes 121, 123, and 125 is possible. A detailed description thereof will be made with reference to FIG.

8 is a plan view of a biosensor in which electrodes of a biosensor are connected to an electrode terminal on a PCB substrate according to an embodiment of the present invention.

The biosensor 100 includes first and second electrode terminals 161 and 163 formed on a PCB substrate 110 to be connected to a power source unit and first and second electrode terminals 161 and 163 formed on a PCB substrate 110 And a third electrode terminal 165. Signal lines 167 for connecting the electrode terminals 161, 163 and 165 to the source electrode 121 and the gate electrode 123 and the drain electrode 125, respectively, As shown in FIG. Here, the power supply unit and the current detection unit are provided in the main body of the sensor on which the biosensor 100 is mounted.

For example, the first electrode terminal 161 is connected to the source electrode 121 to apply a (+) voltage, and the second electrode terminal 163 is connected to the gate electrode 123 to apply a negative And the third electrode terminal 165 may be connected to the drain electrode 125 to detect a current signal output from the drain electrode 125. [ (+) Voltage to the gate electrode 123 according to the operation principle of the field-effect transistor (N-channel, P-channel). Here, electrode terminal connection at the source electrode 121 and the drain electrode 125 may be interchanged.

The signal lines 167 are connected to the sensor film 140 which occupies a relatively larger area than the electrodes 121, 123 and 125 of the biosensor 100, And may be implemented on the lower surface of the PCB substrate 110 to minimize the occurrence of a short circuit.

The foregoing description is merely illustrative of the present invention, and various modifications may be made by those skilled in the art without departing from the spirit of the present invention. Therefore, the embodiments disclosed in the specification of the present invention should be interpreted by the following claims, and all the techniques within the scope of equivalents should be construed as being included in the scope of the present invention.

100: Biosensor 110: PCB substrate
120: conductive material 121: source electrode
123: gate electrode 125: drain electrode
130: first insulating film 140: sensing film
150: second insulating film
161, 163, 165: electrode terminals 167: signal lines

Claims (9)

A printed circuit board (PCB) substrate on which circuit patterns are formed;
A source electrode, a gate electrode, and a drain electrode formed on the printed circuit board at predetermined intervals;
A first insulating layer formed on the gate electrode; And
A sensing film laminated on the printed circuit board on which the first insulating film is formed so that the source electrode and the drain electrode are connected to each other;
.
The method according to claim 1,
The sensing layer
Carbon nanotube or graphene,
The upper surface of the printed circuit board corresponding to the source electrode, the gate electrode and the drain electrode, and the upper surface of the gate electrode,
Wherein the source electrode and the drain electrode overlap each other on the upper surface of the source electrode and the drain electrode.
The method according to claim 1,
And a second insulating layer formed to cover at least one of the source electrode and the drain electrode to prevent a short circuit between the source electrode and the drain electrode.
Further comprising a biosensor.
The method according to claim 1,
First and second electrode terminals formed on the printed circuit board for connection with a power supply unit;
A third electrode terminal formed on the printed circuit board to connect to the current detection unit;
Signal lines formed on a lower surface of the printed circuit board so as to electrically connect the first and second electrode terminals to the source electrode and the gate electrode and to electrically connect the third electrode terminal to the drain electrode;
.
Stacking a conductive material for forming an electrode on a printed circuit board (PCB) substrate on which a circuit pattern is formed;
Forming a source electrode, a gate electrode, and a drain electrode on the substrate by patterning the conductive material;
Forming a first insulating film on the gate electrode; And
Forming a sensing film so that the source electrode and the drain electrode are connected to each other on the printed circuit board on which the first insulating film is formed;
The method comprising the steps of:
6. The method of claim 5,
Forming a second insulating film so as to cover at least one of the source electrode and the drain electrode in order to prevent a short circuit between the source electrode and the drain electrode;
Further comprising the steps of:
6. The method of claim 5,
Wherein forming the sensing layer comprises:
The sensing film is formed of carbon nanotubes or graphenes,
The sensing film is stacked on the upper surface of the printed circuit board corresponding to the source electrode, between the gate electrode and the drain electrode, and on the upper surface of the gate electrode,
Wherein the source electrode and the drain electrode overlap each other on the upper surface of the source electrode and the drain electrode.
6. The method of claim 5,
The forming of the first insulating layer and the forming of the sensing layer may include:
Ink-jet printing method.
6. The method of claim 5,
Forming first and second electrode terminals on the printed circuit board for connection to a power supply;
Forming a third electrode terminal on the printed circuit board to connect to the current detection unit;
Forming signal lines on the lower surface of the printed circuit board so as to electrically connect the first and second electrode terminals to the source electrode and the gate electrode and to electrically connect the third electrode terminal to the drain electrode;
Further comprising the steps of:

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