KR20100112699A - Gas sensing device and method for manufacturing the same - Google Patents

Abstract

PURPOSE: A gas sensing device and a method for manufacturing the same are provided to reduce the manufacturing cost of a gas sensing device by excluding a separate printed circuit board. CONSTITUTION: A gas sensing device(1000) comprises a gas sensing board(100), a packaging board(200), a first bonding pattern(300) and a second bonding pattern(400). The gas sensing board includes a gas sensing part(160) whose electric resistance changes when contacting a gas desired to be detected. The packaging board is located on the gas sensing board to package the gas sensing board. The first bonding pattern is formed on the gas sensing board opposite to the packaging board and has a first polymer. The second bonding pattern is formed on the packaging board to be bonded with the first bonding pattern and has a second polymer different from the first polymer.

Description

Gas sensing device and manufacturing method of gas sensing device {GAS SENSING DEVICE AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to a gas sensing device, and more particularly, to a gas sensing device using MEMS (Micro Electro Mechanical Systems) technology and a manufacturing method thereof.

In general, the gas sensing device is for detecting a specific gas, and when the gas sensing unit included in the gas sensing device is exposed to a specific gas, the conductivity of the semiconductor, which is a sensing material of the gas sensing unit, changes or electromotive force is generated. The specific gas can be detected by measuring the change in conductivity or the generated electromotive force of the semiconductor to measure the change in electrical resistance of the semiconductor.

1 is a cross-sectional view of a conventional gas sensing device.

As shown in FIG. 1, the conventional gas sensing device 1 includes a printed circuit board 10, a gas sensing substrate 20, and a cover 30.

The printed circuit board 10 includes a circuit pattern for gas sensing, and a substrate pad 11 connected to the circuit pattern is positioned on the printed circuit board 10. A portion of the printed circuit board 10 is recessed from the upper surface of the printed circuit board 10 so that the gas sensing substrate 20 is seated.

The gas sensing substrate 20 includes a substrate 21, an insulating layer 22, a heating unit 23, an insulating unit 24, an electrode unit 25, a gas sensing unit 26, and an electrode pad 27. do.

The substrate 21 is formed from a silicon wafer, and the insulating layer 22 is positioned on the substrate 21.

The insulating layer 22 includes silicon oxide, silicon nitride, or the like. The heating part 23 is located on the insulating layer 22.

The heating unit 23 serves to heat the gas sensing unit 26 to a temperature at which the gas sensing unit 26 can exhibit optimal performance. The heating unit 23 includes a metal material such as platinum (Pt) in which the properties of electrical conductivity are not degraded in a high temperature environment. The heating part 23 is connected to the electrode pad 27.

The insulating part 24 is positioned between the heating part 23 and the electrode part 25, and serves to prevent a short circuit between the heating part 23 and the electrode part 25.

The electrode part 25 serves to detect a change in the electrical resistance of the gas sensing unit 26 by the gas introduced from the outside. The electrode portion 25 is connected to the electrode pad 27.

The gas sensing unit 26 is a portion indicating a change in electrical resistance as the gas is in direct contact with a gas to be detected and adsorbs the gas, and includes a metal oxide having a semiconductor property. When the gas introduced from the outside comes into contact with the gas sensing unit 26 to cause a chemical reaction, electrons are exchanged between the gas and the gas sensing unit 26, so that a change in electrical resistance of the gas sensing unit 26 occurs. Done.

The electrode pad 27 is connected to the heating unit 23 and the electrode unit 25, and is connected to the substrate pad 11 positioned on the printed circuit board 10 through a wire w. In other words, the heating part 23 and the electrode part 25 are connected to a circuit pattern for gas sensing formed on the printed circuit board 10 through the electrode pad 27, the wire w and the substrate pad 11. .

The cover 30 protects the gas sensing substrate 20 from external shock.

As such, the conventional gas sensing device 1 manufactures the printed circuit board 10, the gas sensing substrate 20, and the cover 30 through a separate process and adheres them to each other, thereby increasing the manufacturing cost. have.

In addition, since the electrical connection between the printed circuit board 10 and the gas sensing substrate 20 is made through the wire w, there is a problem that the reliability of gas sensing is lowered.

Meanwhile, in order to connect the printed circuit board 10 and the gas sensing substrate 20, the wire w must be bonded to the electrode pad 27. In general, since the electrode pad 27 and the wire w are formed of a metal, the temperature around the electrode pad 27 to the temperature at which the metal can melt when bonding the wire w to the electrode pad 27 is obtained. Should be raised. However, there is a problem in that the crystal structure of the gas sensing unit 26 is changed by the high ambient temperature caused by the bonding process, thereby deteriorating the electrical performance of the gas sensing unit 26.

In addition, after the gas sensing substrate 20 is connected to the printed circuit board 10, the cover 30 must be bonded to the printed circuit board 10, and the cover 30 is bonded to the printed circuit board 10. When the temperature around the cover 30 must be raised to a relatively high temperature, the crystal structure constituting the gas sensing unit 26 is changed by this high ambient temperature, thereby deteriorating the electrical performance of the gas sensing unit 26. There was a problem.

That is, the electrical performance of the gas sensing unit 26 is lowered due to the increase in the ambient temperature by the bonding process, thereby deteriorating the sensing performance of the gas sensing unit 26 with respect to the gas.

The first embodiment of the present invention is to solve the above-described problems, an object of the present invention is to provide a gas sensing device and a manufacturing method of the gas sensing device that can reduce the manufacturing cost by improving the structure.

In addition, an object of the present invention is to provide a gas sensing device and a method for manufacturing the gas sensing device, which can improve the reliability of the gas sensing by improving the connection structure between the gas pattern and the circuit pattern for gas sensing.

In addition, an object of the present invention is to provide a gas sensing device and a method for manufacturing the gas sensing device, which can improve the sensing performance of the gas sensing part by improving a packaging method for packaging the gas sensing part.

After extensive research and various experiments, the inventors of the present application have found that the packaging performance of the gas sensing unit is improved when two polymers are used as the bonding polymer for packaging the gas sensing unit. . In particular, as the two polymers, it was found that the packaging performance for the gas sensing unit is most effective when using polyimide and parylene.

As a technical means for achieving the above technical problem, the first aspect of the present invention is a gas sensing device, the gas sensing substrate having a gas sensing unit for changing the electrical resistance when in contact with the gas to be detected, the gas sensing substrate A packaging substrate formed on the gas sensing substrate so as to face the packaging substrate, the first bonding pattern comprising a first polymer, and a first bonding pattern formed on the packaging substrate; A gas sensing device is bonded to a pattern and includes a second bonding pattern including a second polymer different from the first polymer.

The gas sensing substrate may include a first substrate, a first substrate insulating layer positioned between the first substrate and the gas sensing unit, a pad unit disposed on the first substrate insulating layer, and connected to the gas sensing unit, Located between the first substrate insulating film and the gas sensing unit, further comprising a heating unit for applying heat to the gas sensing unit and an electrode unit for connecting between the pad unit and the gas sensing unit, the first bonding pattern is the The pad portion can be exposed.

The packaging substrate may be disposed on the first substrate, the second substrate forming a detection space surrounding the gas sensing unit, and formed to penetrate the second substrate in correspondence with the gas sensing unit to allow the gas to pass therethrough. A second through pattern, a through hole formed through the second substrate corresponding to the pad part, and a connection part disposed in the through hole and connected to the pad part through the through hole; May expose the connection portion.

One of the first polymer and the second polymer may be polyimide, and the other may be parylene.

In addition, the second aspect of the present invention provides a gas sensing device, comprising the steps of: (a) providing a gas sensing substrate comprising a gas sensing unit in which the electrical resistance changes when in contact with the gas to be detected, (b) the Providing a packaging substrate for packaging a gas sensing substrate, (c) forming a first bonding pattern comprising a first polymer on the gas sensing substrate facing the packaging substrate during packaging; and (d) Forming a second bonding pattern comprising a second polymer different from the first polymer on the packaging substrate to bond the first bonding pattern to each other; and (e) the first bonding pattern and the second bonding pattern cross each other. And bonding the package to the packaging substrate on the gas sensing substrate.

At least one of the steps (a) and (b) may be performed using a MEMS process.

The step (a) may include preparing a first substrate, forming a first substrate insulating film on the first substrate, and a heating unit applying heat to the gas sensing unit on the first substrate insulating film, and the gas. And forming a pad part connected to a sensing part and an electrode part positioned between the first substrate insulating film and the gas sensing part to connect the pad part and the gas sensing part, and the step (c) includes: The first bonding pattern may be performed to expose the pad part.

The step (b) may include preparing a second substrate, forming a detection space formed in the second substrate in correspondence with the gas sensing unit, and corresponding to the gas sensing unit in the second substrate. Forming a through hole penetrating the second substrate and a gas through portion penetrating through the second substrate, and a connecting portion connected to the pad portion through the through hole in the through hole; And forming a second bonding pattern, wherein the second bonding pattern exposes the connection portion.

In step (c) and step (d), one of the first polymer and the second polymer may be polyimide, and the other may be parylene.

The step (e) may be performed in a temperature environment of 100 degrees Celsius to 200 degrees Celsius.

According to one of the problem solving means of the present invention described above, by improving the structure of the packaging substrate to omit a separate printed circuit board, there is a technical effect that can reduce the manufacturing cost.

In addition, by improving the structure of the packaging substrate, there is a technical effect that can improve the gas sensing reliability.

In addition, by packaging the gas sensing unit using the first bonding pattern including the first polymer and the second bonding pattern including the second polymer, there is a technical effect of improving the sensing performance of the gas sensing unit.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Throughout the specification, when a member is located “on” another member, this includes not only when one member is in contact with another member but also when another member exists between the two members. In addition, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless otherwise stated.

Hereinafter, a gas sensing device according to a first embodiment of the present invention will be described with reference to FIGS. 2 and 3.

2 is a cross-sectional view of the gas sensing device according to the first embodiment of the present invention, Figure 3 is a top plan view of the gas sensing device according to the first embodiment of the present invention.

As shown in FIG. 2, the gas sensing device 1000 according to the first embodiment of the present invention may include a gas sensing substrate 100, a packaging substrate 200, a first bonding pattern 300, and a second bonding pattern ( 400).

The gas sensing substrate 100 may include a first substrate 110, a first substrate insulating layer 120, a heating unit 130, an insulating unit 140, an electrode unit 150, a gas sensing unit 160, and a pad unit ( 170 and bump portion 180.

The first substrate 110 is formed from a wafer containing silicon (Si) as a material. The first substrate insulating layer 120 is positioned on the first substrate 110.

The first substrate insulating layer 120 includes silicon oxide (SiO 2), silicon nitride (SiN x), or the like. The heating unit 130 is positioned on the first substrate insulating layer 120.

The heating unit 130 serves to heat the gas sensing unit 160 to a temperature at which the gas sensing unit 160 can exhibit optimal performance. The heating unit 130 includes a metal material such as platinum (Pt) and a conductive material such as polycrystalline silicon (poly Si) in which the properties of electrical conductivity are not degraded in a high temperature environment. The heating unit 130 is connected to the pad unit 170.

The insulating unit 140 is positioned between the heating unit 130 and the electrode unit 150, and serves to prevent a short circuit between the heating unit 130 and the electrode unit 150.

The electrode unit 150 serves to detect a change in electrical resistance of the gas sensing unit 160 by the gas introduced from the outside. The electrode unit 150 includes a metal material such as platinum (Pt) and a conductive material such as polycrystalline silicon, in which the properties of electrical conductivity are not degraded in a high temperature environment. The electrode unit 150 is connected to the pad unit 170.

The gas sensing unit 160 shows a change in electrical resistance as the gas is in direct contact with a gas to be detected and adsorbs the gas, and the tin oxide (SnO₂), tungsten oxide (WO₃), and titanium oxide having semiconductor properties Metal oxides such as (TiO 2); When the gas introduced from the outside comes into contact with the gas sensing unit 160 to cause a chemical reaction, electrons are exchanged between the gas and the gas sensing unit 160, so that a change in electrical resistance of the gas sensing unit 160 occurs. do.

The pad unit 170 is partially connected to the heating unit 130, and the rest of the pad unit 170 is connected to the electrode unit 150. The pad unit 170 is connected to the gas sensing unit 160 by the electrode unit 150 and to the connection unit 250 of the packaging substrate 200 to be described later. The pad unit 170 is connected to a circuit pattern for gas sensing formed on another substrate through the connection unit 250.

The bump part 180 is positioned on the pad part 170. The bump unit 180 is positioned between the pad unit 170 and the connection unit 250 to connect the pad unit 170 and the connection unit 250. The bump unit 180 may include a conductive metal material such as gold (Au), silver (Ag), and copper (Cu).

The packaging substrate 200 is positioned on the gas sensing substrate 100 as described above.

As shown in FIGS. 2 and 3, the packaging substrate 200 may include a second substrate 210, a second substrate insulating layer 220, a gas through part 230, a through hole 240, and a connection part 250. Include. The second substrate 210 is formed from a wafer containing silicon as a material. The second substrate 210 surrounds the gas sensing unit 160 so that the detection space S is formed around the gas sensing unit 160 of the gas sensing substrate 100. That is, the detection space S surrounds the gas sensing unit 160, and the gas introduced from the outside is located in the detection space S during gas sensing by the gas sensing device 1000.

The second substrate insulating layer 220 is made of an insulating material including silicon oxide (SiO 2) or silicon nitride (SiN x). The second substrate insulating film 220 surrounds the surface of the second substrate 210, and the second substrate insulating film 220 corresponding to the detection space S faces the detection space S directly. That is, the second substrate insulating layer 220 facing the gas sensing unit 160 of the gas sensing substrate 100 is floating with respect to the gas sensing unit 160 with the detection space S therebetween. The second substrate insulating film 220 may include a plurality of insulating films. In this case, a plurality of insulating films may be formed so that the lattice structures of neighboring insulating films may cross each other. As the lattice structures of the neighboring plurality of insulating films cross each other, the plurality of insulating films play a role of reinforcing mutual insulation and elastic strength, thereby preventing damage to the packaging substrate 200 due to external interference.

The gas penetrating portion 230 penetrates through the second substrate 210 in correspondence with the gas sensing unit 160 and the detection space S. FIG. The gas penetrating part 230 serves as a channel through which gas flows into the detection space S in which the gas sensing unit 160 is located during gas sensing by the gas sensing device 1000.

The through hole 240 penetrates the second substrate 210 to correspond to the pad 170 and the bump 180 with the gas through part 230 therebetween. The connection part 250 is positioned in the through hole 240.

The connection part 250 is located in the through hole 240 and is connected to the pad part 170 by the bump part 180. The connection part 250 is connected to a circuit pattern for gas sensing formed on another substrate, and serves to connect between the pad unit 170 and the circuit pattern for gas sensing. The connection part 250 includes a conductive metal material such as gold (Au), silver (Ag), and copper (Cu).

In another embodiment, the packaging substrate 200 may include a circuit pattern for gas sensing connected to the connection unit 250, and the circuit pattern for gas sensing may be formed on the second substrate 210. have. In addition, the circuit pattern for gas sensing may exchange electrical signals with the heating unit 130 and the electrode unit 150 of the gas sensing substrate 100 through the connection unit 250 and the pad unit 170. That is, the circuit pattern for gas sensing may be formed in the form of chip on silicon (COG) including a plurality of thin film transistors.

The first bonding pattern 300 is formed on the gas sensing substrate 100 with the pad unit 170 and the gas sensing unit 160 interposed therebetween to face the gas sensing substrate 100. The first bonding pattern 300 includes a first polymer including polyimide or parylene, and is bonded to the second bonding pattern 400 to package the substrate 200 on the gas sensing substrate 100. ). The first bonding pattern 300 is patterned in a predetermined form so as not to cover the pad portion 170, the bump portion 180, and the gas sensing portion 160 of the gas sensing substrate 100. The first bonding pattern 300 bonds with the second bonding pattern 400 to hermetic the pad unit 170, the bump unit 180, and the connection unit 250.

The second bonding pattern 400 is formed on the packaging substrate 200 with the connection portion 250 and the detection space S interposed therebetween to correspond to the first bonding pattern 300 patterned in a predetermined shape. The first bonding pattern 300 includes a second polymer including polyimide or parylene. The second polymer is parylene when the first polymer included in the first bonding pattern 300 is polyimide, and is polyimide when the first polymer is parylene. That is, the first polymer and the second polymer include different polymers. The second bonding pattern 400 bonds the first bonding pattern 300 to package the packaging substrate 200 on the gas sensing substrate 100. The second bonding pattern 400 is patterned in a predetermined shape so as not to cover the connection portion 250 and the detection space S of the packaging substrate 200. The second bonding pattern 400 bonds with the first bonding pattern 300 to hermetic the pad part 170, the bump part 180, and the connection part 250.

Hereinafter, a method of manufacturing the gas sensing device according to the second embodiment of the present invention will be described with reference to FIGS. 4 to 10.

4 is a flowchart illustrating a method of manufacturing a gas sensing device according to a second embodiment of the present invention, and FIGS. 5 to 10 are cross-sectional views illustrating a method of manufacturing a gas sensing device according to a second embodiment of the present invention. .

As shown in FIG. 4 and FIG. 5, first, a gas sensing substrate 100 is prepared (S100).

Specifically, the first substrate 110, the first substrate insulating film 120, the heating unit 130, the insulating unit 140, using MEMS (Micro Electro Mechanical Systems) technology such as a photolithography process, A gas sensing substrate 100 including an electrode unit 150, a gas sensing unit 160, a pad unit 170, and a bump unit 180 is prepared.

More specifically, first, a silicon-containing oxide in a water (H 2 O) atmosphere using a wet thermal oxidation method on a first substrate 110, which is a single side polished silicon (Si) wafer, is used. 1 The substrate insulating film 120 is formed to a thickness of 4000 kPa to 6000 kPa.

Next, after the conductive layer and the insulating layer including tin (Sn), platinum (Pt), and the like are formed alternately on the first substrate insulating film 120, the heating unit 130, using a photolithography process, The insulating part 140, the electrode part 150, the gas sensing part 160, and the pad part 170 are formed. The thickness of the conductive layer used to form the heating unit 130, the electrode unit 150 and the gas sensing unit 160 is 2000 kPa to 5000 kPa, and the etching method used in the photolithography process may include reactive ion etching, RIE) method.

Next, after the conductive layer including gold (Au), silver (Ag), copper (Cu), and the like is formed on the pad unit 170, the bump part may be formed using a photolithography process including an ion reaction etching method. 180).

In another embodiment, the bump unit 180 may be formed using a printing process using a soft stamp or a hard stamp, or may be formed using a plating process using the pad unit 170 as a seed layer. .

The gas sensing substrate 100 is provided by the above process.

Next, as shown in FIGS. 6 to 9, the packaging substrate 200 is prepared (S200).

Specifically, first, as shown in FIG. 6, the upper and lower surfaces of the second substrate 210 formed of a double side polished silicon (Si) wafer are subjected to a wet thermal oxidation method in a water (H 2 O) environment. And the second substrate insulating film 220 formed of silicon oxide (SiO 2) on the upper and lower surfaces of the second substrate 210 to have a thickness of 4000 kPa to 6000 kPa.

Next, after removing the second substrate insulating film 220 corresponding to the detection space S to be formed later by using a photolithography process including an ion reaction etching method, deep ions using the second substrate insulating film 220 as a mask The detection space S is formed by recessing a lower surface of the second substrate 210 corresponding to the detection space S to be formed later by using a deep reactive ion etching (DRIE) method. In this case, the etching surface of the second substrate 210 is selectively formed of at least one of an acute angle, a right angle, or an obtuse angle depending on the crystal direction of silicon. The area of the detection space S is 0.3 * 0.3 mm² to 0.8 * 0.8 mm² and the height is 50 to 200 m.

Next, the second substrate insulating layer 220 corresponding to the gas penetrating portion 230 and the through hole 240 to be formed later is removed using a photolithography process including an ion reaction etching method, and then the second substrate insulating layer 220 is removed. Through the gas penetrating portion 230 and the through part of the second substrate 210 corresponding to the gas penetrating portion 230 and the through hole 240 to be formed later by using a deep ion reaction etching method using a mask as a mask. The hole 240 is formed. The gas through part 230 and the through hole 240 are formed in a circular shape, and the diameter of the gas through part 230 is 30 μm to 70 μm, and the height is 300 μm to 700 μm. In addition, the diameter of the through hole 240 is 40 μm to 120 μm, and the height is 350 μm to 750 μm.

Next, as illustrated in FIG. 7, water (H 2 O) is formed on the recessed lower surface of the second substrate 210 corresponding to the detection space S and one surface of the second substrate 210 corresponding to the through hole 240. Oxidation is performed using a wet thermal oxidation method in an environment, and silicon oxide (SiO₂) is formed on the bottom surface of the second substrate 210 corresponding to the detection space S and on one surface of the second substrate 210 corresponding to the through hole 240. ) Is formed to a thickness of 4000 kPa to 6000 kPa.

Next, as shown in FIG. 8, the connection part 250 is formed by filling conductive materials such as gold (Au), silver (Ag), and copper (Cu) in the through hole 240 using a plating process or the like. By the plating process, the conductive material protrudes not only in the through hole 240 but also on the second substrate 210.

Next, as shown in FIG. 9, the conductive material protruding from the second substrate 210 and the upper and lower surfaces of the second substrate 210 are formed using a chemical mechanical polishing (CMP) process. The second substrate insulating film 220 is removed. The flatness of the top and bottom surfaces of the second substrate 210 is improved by the chemical mechanical polishing process.

Next, the upper and lower surfaces of the second substrate 210 exposed by the chemical mechanical polishing process are oxidized by a wet thermal oxidation method in a water (H 2 O) environment, and the silicon oxide is deposited on the upper and lower surfaces of the second substrate 210. The second substrate insulating film 220 formed of (SiO 2) is formed again to a thickness of 4000 kPa to 6000 kPa.

The packaging substrate 200 is provided by the above process.

Next, as shown in FIG. 10, the first bonding pattern 300 is formed on the gas sensing substrate 100 (S300).

In detail, the first bonding pattern 300 including parylene as the first polymer is formed on the gas sensing substrate 100. The first bonding pattern 300 is patterned in a predetermined shape such that the pad part 170, the bump part 180, and the gas sensing part 160 of the gas sensing substrate 100 are exposed. The first bonding pattern 300 is formed by forming a first polymer layer including parylene and then patterning the first polymer to form the first bonding pattern 300 or by using a printing process using a soft stamp or a hard stamp. can do.

Next, a second bonding pattern 400 is formed on the packaging substrate 200 (S400).

In detail, a second bonding pattern 400 including polyimide as a second polymer is formed on the packaging substrate 200. The second bonding pattern 400 is patterned in a predetermined shape such that the connection portion 250 and the detection space S of the packaging substrate 200 are exposed. The second bonding pattern 400 is formed by forming a second polymer layer including polyimide and then patterning the second polymer to form the second bonding pattern 400 or using a printing process using a soft stamp or a hard stamp. can do.

In another embodiment, when the first polymer of the first bonding pattern 300 is polyimide, the second polymer of the second bonding pattern 400 may be parylene.

In another embodiment, the first bonding pattern 300 may be any polymer of the first polymer, wherein the second polymer of the second bonding pattern 400 is different from the first polymer. It may be a polymer.

Next, the packaging substrate 200 is packaged on the gas sensing substrate 100 (S500).

Specifically, after bonding the gas sensing substrate 100 and the packaging substrate 200 to each other such that the first bonding pattern 300 and the second bonding pattern 400 are in contact with each other, a temperature of 100 degrees to 200 degrees Celsius The packaging substrate 200 is packaged on the gas sensing substrate 100 by performing low temperature vacuum bonding in an environment. As such, the first bonding pattern 300 and the second bonding pattern 400 are bonded to each other, such that the pad part 170, the bump part 180, and the connection part 250 are connected to the first bonding pattern 300 and the second bonding pattern 400. It is hermetic by the bonding pattern 400.

The gas sensing device according to the first embodiment of the present invention is manufactured by the method of manufacturing the gas sensing device according to the second embodiment of the present invention.

As described above, the manufacturing method and the manufacturing cost of the gas sensing device and the gas sensing device according to the present invention do not require a process of separately manufacturing a cover as compared to the conventional gas sensing device having a separate cover. . In addition, when the packaging substrate is manufactured in chip-on-silicon form, manufacturing time and manufacturing cost are reduced because a separate printed circuit board for gas sensing is not required.

In addition, when the connection between the gas sensing substrate 100 and the separate printed circuit board is performed through the connection unit 250, the electrical connection between the gas sensing substrate 100 and the separate printed circuit board is connected to the connection unit 250. Since it is made through, the reliability of gas sensing is improved.

In addition, since there is no bonding process between metals for electrical connection to the pad unit 170, when manufacturing the gas sensing device 1000, it is not necessary to raise the ambient temperature to a temperature at which the metal can melt. That is, since the temperature at the time of manufacturing the gas sensing device 1000 is 100 to 200 degrees Celsius, which is a temperature below the melting temperature of the metal, the gas sensing unit 160 may be changed by the manufacturing process temperature of the gas sensing device 1000. The crystal structure constituting the same does not change, and thus, the electrical performance of the gas sensing unit 160 is prevented from being lowered, thereby reducing the sensing performance of the gas sensing device 1000.

In addition, by packaging the packaging substrate 200 on the gas sensing substrate 100 using the bonding of parylene and polyimide as two kinds of polymers instead of a single polymer, the inventors of the present application have conducted in-depth studies and various experiments. Compared to bonding using a single polymer at the end, bonding can be performed even when the ambient temperature is set to 100 to 200 degrees Celsius, and the bonding strength and durability of the packaging substrate 200 to the gas sensing substrate 100 after bonding. It was found to be substantially twice as resistant to this external stress.

In addition, since the entire process of the gas sensing device is manufactured by the MEMS process, not only the gas sensing device can be miniaturized, but also an electrically, thermally and mechanically stable gas sensing device is provided.

In addition, since the entire process of the gas sensing device is manufactured by the MEMS process, mass production can be performed in a single process, thereby reducing manufacturing costs. More specifically, each silicon wafer having a plurality of gas sensing substrates 100 and a plurality of packaging substrates 200 formed thereon is bonded to each other using the gas sensing substrate 100 and the packaging substrate 200 formed from the silicon wafer. After bonding each of the packaging substrate 200 to each of the gas sensing substrate 100 to package, cut and manufactured by each gas sensing device 1000 to mass-produce in one process.

The foregoing description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

1 is a cross-sectional view of a conventional gas sensing device,

2 is a cross-sectional view of a gas sensing device according to a first embodiment of the present invention,

3 is a top plan view of a gas sensing device according to a first embodiment of the present invention,

4 is a flowchart illustrating a method of manufacturing a gas sensing device according to a second embodiment of the present invention.

5 to 10 are cross-sectional views illustrating a method of manufacturing a gas sensing device according to a second embodiment of the present invention.

Claims (10)

In the gas sensing device, A gas sensing substrate having a gas sensing unit in which electrical resistance changes when contacted with a gas to be detected; A packaging substrate positioned on the gas sensing substrate to package the gas sensing substrate; A first bonding pattern formed on the gas sensing substrate to face the packaging substrate, the first bonding pattern comprising a first polymer, and A second bonding pattern formed on the packaging substrate and bonded to the first bonding pattern and including a second polymer different from the first polymer Gas sensing device comprising a. The method of claim 1, The gas sensing substrate, First substrate, A first substrate insulating layer positioned between the first substrate and the gas sensing unit, A pad part disposed on the first substrate insulating layer and connected to the gas sensing part; A heating unit positioned between the first substrate insulating layer and the gas sensing unit and applying heat to the gas sensing unit; An electrode unit connecting between the pad unit and the gas sensing unit More, And the first bonding pattern exposes the pad part. The method of claim 2, The packaging substrate, A second substrate positioned on the first substrate and forming a detection space surrounding the gas sensing unit; A gas penetrating part formed to penetrate the second substrate so as to penetrate the gas; A through hole formed through the second substrate in correspondence to the pad part; A connection part located in the through hole and connected to the pad part through the through hole; Including; And the second bonding pattern exposes the connection portion. The method of claim 1, Any one of the first polymer and the second polymer is a polyimide, the other is parylene (parylene) gas sensing device. In the manufacturing method of the gas sensing device, (a) preparing a gas sensing substrate including a gas sensing unit in which electrical resistance changes when contacted with a gas to be detected; (b) providing a packaging substrate for packaging the gas sensing substrate, (c) forming a first bonding pattern including a first polymer on the gas sensing substrate facing the packaging substrate during the packaging; (d) forming a second bonding pattern comprising a second polymer different from the first polymer on the packaging substrate to bond with the first bonding pattern during the packaging; (e) packaging the packaging substrate on the gas sensing substrate by bonding the first bonding pattern and the second bonding pattern to each other; Method of manufacturing a gas sensing device comprising a. The method of claim 5, At least one of the steps (a) and (b), Method of manufacturing a gas sensing device that is carried out using a MEMS (Micro Electro Mechanical Systems) process. The method of claim 6, In step (a), Preparing a first substrate, Forming a first substrate insulating film on the first substrate, and A heating part that heats the gas sensing part on the first substrate insulating film, a pad part connected to the gas sensing part, and positioned between the first substrate insulating film and the gas sensing part, the pad part and the gas sensing part Forming an electrode portion connecting between Including; Step (c) is, And the first bonding pattern is exposed to expose the pad part. The method of claim 7, wherein In step (b), Preparing a second substrate, Forming a detection space formed in the second substrate in a depression corresponding to the gas sensing unit; Forming a through hole penetrating the second substrate corresponding to the gas sensing part and a through hole penetrating the second substrate corresponding to the pad part in the second substrate; and Forming a connection part connected to the pad part through the through hole in the through hole; Including; In step (d), And manufacturing the second bonding pattern to expose the connection part. The method of claim 5, In the step (c) and (d), Any one of the first polymer and the second polymer is a polyimide, and the other is parylene. The method of claim 5, In step (e), Method for producing a gas sensing device is performed in a temperature environment of 100 degrees Celsius to 200 degrees Celsius.

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