KR101826265B1 - Gas sensor package - Google Patents

Abstract

The present invention provides a gas sensor package. A protective cap for covering a gas sensor element on a main board includes a cap main body made of synthetic resin; and a metal flange provided on the lower end of the cap body and mounted on the main board by soldering. So, the driving temperature of a gas sensor element can be more stably maintained because the characteristic of a synthetic resin has a heat capacity larger than that of a metal. It is possible to ensure long-term usability with improved airtightness and durability with respect to a joint part by a solder layer between the main board and the protective cap.

Description

Gas sensor package {GAS SENSOR PACKAGE}

An embodiment of the present invention relates to a gas sensor package that senses the presence and concentration of a gas, such as carbon dioxide (CO2).

Recently, the paradigm of Information & Communication Technology (ICT) or Internet of Things (IoT) technology has shifted away from competition based on OS (Operating System) and hardware, The demand for sensors is rapidly increasing as they are shifting toward providing the UX (User Experience).

In particular, CO2 sensors and TVOC (Total Volatile Organic Compounds) sensors are representative indoor environmental monitoring sensors. They are combined with industrial trends such as compliance with environmental regulations and reduction of air-conditioning energy. HVAC (Heating, Ventilating and Air Conditioning) (Building Energy Management System, BEMS), smart home, and various IoT services.

Among the gas sensors that detect the presence and concentration of the gas, the most widely used methods are solid electrolyte gas sensors and metal oxide semiconductor (MOS) gas sensors. They are simple in structure, have a long life span and low in production cost, and are applied to various fields based on mass demand.

1 is a perspective view showing a general gas sensor package. 1, the gas sensor package generally includes a stem 1 (or a substrate) and a protective cap 3. The stem (1) is configured to support the gas sensor element, and the protective cap (3) covers the supported gas sensor element to protect the gas sensor element from the outside. The protective cap 3 is adhered to the top of the stem 1 by an adhesive. The gas sensor element may comprise a solid electrolyte gas sensor or a metal oxide semiconductor gas sensor.

In such a gas sensor package, the protective cap 3 is made of metal. The driving temperature of the gas sensor element in the protective cap 3 can be changed to a large extent in a short time in accordance with the temperature change outside the protective cap 3 due to the characteristic of the metal having a small heat capacity, There is a problem that the accuracy is lowered.

Further, the adhesive (adhesive layer) used to assemble the stem 1 and the protective cap 3 may be damaged due to the normal high temperature driving temperature of the gas sensor element, so that the adhesive force of the adhesive can be gradually weakened, A problem of airtightness and durability deterioration with respect to the joint portion between the protective cap 1 and the protective cap 3 may occur. As the adhesive is heated to the high temperature driving temperature of the gas sensor element, gas may be generated from the adhesive, and the measurement accuracy of the gas sensor element may be lowered due to the gas generated from the adhesive agent.

Korean Patent Publication No. 10-2015-0111102 (Oct.

It is an object of the present invention to provide a gas sensor package which is more advantageous in terms of improving the functionality and long-term usability of the protective cap accommodating the gas sensor element.

The problems to be solved are not limited thereto, and other matters not mentioned can be clearly understood by those skilled in the art from the following description.

According to an embodiment of the present invention, there is provided a semiconductor device comprising: a main substrate which is a printed substrate; A gas sensor element mounted on the main substrate and electrically connected to a wiring of the main substrate; And a protective cap covering the gas sensor element and shielding the gas sensor element from the outside, wherein the protective cap includes: a cap body having a lower end opened and having an element accommodating space for accommodating the gas sensor element therein; And a flange which is provided along the lower end of the cap body at the lower end of the cap body and is made of metal and the entire lower surface is soldered to the main board, A gas sensor package may be provided that includes a large material.

The protective cap may further include at least one reinforcing frame protruding from the upper portion of the flange toward the wall of the cap body to be buried in the wall through the lower end of the wall. The reinforcing frame may be buried in the wall during the molding of the cap body so as to be embedded in the wall.

The reinforcing frame may be embedded in the wall in a state inclined with respect to the vertical direction.

The reinforcement frame may be provided with at least one or more than one of engagement holes, engagement projections, and engagement grooves for structural coupling between the wall and the reinforcement frame.

The cap body may be provided with a gas inlet / outlet passage for communicating the element accommodating space with the outside of the cap body. Wherein the gas inlet / outlet passage includes: a first passage communicating with the element accommodating space; And a second passage extending from the first passage and communicating with the outside.

The second passage includes: a first hole extending from the first passage; And a second hole extending from the first hole. Wherein a cross-sectional area of the first hole is larger than that of the first passage, and a cross-sectional area of the second hole is larger than that of the first hole, so that a distance between the first passage and the first hole, A first step difference surface and a second step difference surface may be provided, respectively.

The first stepped surface may be provided with a first gas permeable member, a first moisture permeable restricting member, or a first gas permeable member and a first moisture permeable restricting member laminated to each other. The second stepped surface may be provided with a second gas permeable member, a second moisture permeable restricting member, or a second gas permeable member and a second moisture permeable restricting member laminated to each other. Thus, the filter can be received in the first hole in which both openings are blocked.

The cap body may be formed of at least one material selected from a large synthetic resin and a ceramics having a larger heat capacity than the metal.

The cap body includes a heat insulating coating layer made of a material such as a synthetic resin having a heat capacity larger than that of a metal, and may be coated with the heat insulating coating layer.

According to an embodiment of the present invention, there is provided a gas sensor device including a main substrate, a gas sensor element on the main substrate, and a protection cap covering the gas sensor element, A cap body having a housing space and formed of metal and having a lower end mounted on the main board by soldering; And a heat insulating layer coated on the cap body.

The gas sensor element may be a type including a solid electrolyte gas sensor, a type including a metal oxide semiconductor gas sensor, or a composite gas sensor provided with at least one of the solid electrolyte gas sensor and the metal oxide semiconductor gas sensor It can be a type that includes.

Means for solving the problems will be more specifically and clarified through the embodiments, drawings, and the like described below. In addition, various solution means other than the above-mentioned solution means may be further proposed.

According to the embodiment of the present invention, since the protective cap accommodating the gas sensor element includes a material such as synthetic resin or ceramic having a large heat capacity as compared with the metal, the temperature change outside the protective cap affects the gas sensor element in the protective cap. The influence can be largely reduced and the driving temperature of the gas sensor element can be more stably maintained.

In addition, since the flange constituting the bottom of the protective cap is made of metal and is mounted on the main board by soldering, the long-term usability can be ensured by the excellent airtightness and durability of the joint portion between the main board and the protective cap. In addition, since the protection cap can be soldered together with the circuit board when the circuit components are soldered on the main board, the protection cap can be mounted without adding a separate process for mounting the protection cap.

Further, since the reinforcing frame protrudes from the flange and is buried in the wall of the cap body, the cap body can be structurally reinforced. Since a hole, a projection or a groove is formed in the reinforcing frame embedded in the wall of the cap body, the coupling force between the cap body and the reinforcing frame can be greatly improved. Further, since the reinforcing frame is inclined with respect to the vertical direction, it is pos- sible to positively prevent the cap body from separating from the reinforcing frame.

Since the cross-sectional area of the first hole is larger than that of the first passage and the cross-sectional area of the second hole is larger than that of the first hole, a gas permeable member or a water permeable member is provided between the first passage and the first hole, (The first stepped surface and the second stepped surface) to which the restraining member is attached can be ensured, whereby the attaching operation of the gas permeable member and the moisture permeation suppressing member can be carried out easily and quickly. In addition, since the gas permeable member or the moisture permeation suppressing member attached to the attachment face (second-stage contact face) between the first hole and the second hole is accommodated in the second hole, it is possible to prevent damage or fall- have.

1 is a perspective view showing a general gas sensor package.
2 and 3 are a perspective view and an exploded perspective view showing a gas sensor package according to a first embodiment of the present invention.
4 is a sectional view showing a gas sensor package according to the first embodiment of the present invention.
5 is a perspective view showing the mounting frame shown in Fig.
6 is a cross-sectional view showing a gas sensor package according to a second embodiment of the present invention.
7 is a perspective view showing a gas sensor package according to a third embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. For a better understanding of the invention, it is to be understood that the size of elements and the thickness of lines may be exaggerated for clarity of understanding. Further, the terms used to describe the embodiments of the present invention are mainly defined in consideration of the functions of the present invention, and thus may be changed depending on the intentions and customs of the user and the operator. Therefore, the terminology should be interpreted based on the contents of the present specification throughout.

2 to 4 are a perspective view, an exploded perspective view, and a cross-sectional view showing a gas sensor package according to a first embodiment of the present invention.

2 to 4, the gas sensor package according to the first embodiment of the present invention includes a main substrate 10, a gas sensor element 20 mounted on the main substrate 10, And a protection cap (30) covering the gas sensor element (20) on the main substrate (10).

Various circuit components (electronic components) for driving the gas sensor element 20 can be mounted on the main board 10. [ For example, the circuit component may be an integrated circuit (IC), a resistor, a condenser, or the like. Some of the circuit components may be disposed close to the gas sensor element 20 and covered with the gas sensor element 20 by the protective cap 30.

Circuit components can be soldered. Specifically, the circuit components are mounted by applying a solder paste on the wiring to be mounted with circuit components on the main board 10 by screen printing or the like, arranging the circuit components on the solder paste applied , Reflow soldering where the solder paste is melted and resolidified.

The gas sensor element 20 may include a heater for heating the sensor body and the sensor body to a high temperature drive temperature. The sensor body may include a first electrode provided on a first surface of the sensing part and a second electrode provided on a first surface of the sensing part or a second surface thereof opposite to the first surface.

Such a gas sensor element 20 has a structure in which the sensing part is a solid electrolyte and the principle that the electromotive force measured at the first electrode which is the sensing electrode and the second electrode which is the reference electrode is changed by the Nernst equation And a solid electrolyte gas sensor configured to detect the presence of the gas and measure the concentration of the gas.

Alternatively, the gas sensor element 20 detects the presence of the gas by using the principle that the sensing part is a metal oxide semiconductor and the electric conductivity of the metal oxide semiconductor is changed by adsorption, oxidation, and reduction reaction of the gas, And a metal oxide semiconductor gas sensor configured to measure a change in electrical conductivity of the metal oxide semiconductor by the first electrode and the second electrode.

Alternatively, the gas sensor element 20 may include a composite gas sensor in which a plurality of types of gas sensors (solid electrolyte gas sensor, metal oxide semiconductor gas sensor, etc.) are appropriately combined for various types of gas detection.

The gas sensor element 20 can be mounted on the main board 10 by soldering. In other words, it can be mounted by reflow soldering used for mounting of circuit components. For this purpose, the gas sensor element 20 may include a contact pad for electrical connection with the wiring of the main board 10. [

4, the protective cap 30 includes a cap body 100 made of a synthetic resin (or ceramic) having excellent heat resistance and a heat capacity larger than that of a metal, a mounting frame 200 made of metal, .

The cap body 100 has a structure in which the lower end thereof is opened. The cap body 100 is provided with an element accommodation space 105 therein. The element accommodating space 105 has a structure communicating with the open lower end of the cap body 100 and houses the gas sensor element 20. [ As described above, when some of the circuit components are covered with the gas sensor element 20 by the protective cap 30, circuit components are accommodated in the element accommodating space 105 together with the gas sensor element 20. [ 2 to 4, the cap body 100 is illustrated as having a rectangular cross-section, but the cap body 100 may be formed to have a circular or polygonal cross-sectional shape other than a rectangular shape. The cap body 100 may be formed in such a shape that the circumference gradually decreases toward the upper side.

5 is a perspective view showing the mounting frame 200. Fig. 4 and 5, the mounting frame 200 is provided in the lower end of the cap body 100 along the circumferential direction of the cap body 100, And at least one reinforcing frame 220 integrally extending upward from the flange 210 and embedded in the wall constituting the cap body 100, . The flange 210 and the reinforcing frame 220 may not be integral but may be coupled to each other. In this case, the flange 210 is made of metal, while the reinforcing frame 220 is made of a material other than metal (preferably a material having a high strength and a heat capacity larger than that of the metal).

The protective cap 30 covers the gas sensor element 20 while being mounted on the main board 10 to protect the gas sensor element 20 from the outside. To mount the protection cap 30, the metal flange 210 is bonded to the main board 10 by reflow soldering. A solder paste (see reference symbol SP) is applied on the wiring to which the protective cap 30 is to be mounted, the protective cap 30 is placed so that the flange 210 is in contact with the solder paste applied, When the re-solidification is performed, the protective cap 30 is mounted on the main substrate 10 while the flange 210 is bonded. Of course, in mounting the protection cap 30, the wiring of the main board 10 to be used is formed in an annular shape corresponding to the flange 210 having an annular structure, and the solder paste used is an annular wiring Respectively.

According to the configuration in which the protection cap 30 is mountable by soldering, solder paste is applied on each wiring to be mounted with the circuit component, the gas sensor element 20 and the protection cap 30, The gas sensor element 20 and the protective cap 30 are disposed on the main substrate 10 and then the solder paste is simultaneously melted and resolidified so that the circuit component, 10) in a single process. Thus, the manufacturing process of the gas sensor package can be simplified.

Further, according to soldering, since the airtightness and durability of the joint portion of the main board 10 and the protective cap 30 are excellent, further improved long-term usability can be ensured.

Since the cap body 100 constituting the remainder of the protection cap 30 except for the bottom of the protection cap 30 is made of synthetic resin having a larger heat capacity than the metal, The influence of the temperature change on the gas sensor element 20 inside the protective cap 30 can be greatly reduced. Accordingly, the gas sensor package according to the first embodiment of the present invention can maintain the driving temperature of the gas sensor element 20 more stably, thereby minimizing the influence of environmental change on the performance of the gas sensor element 20 It is possible to maximize the functionality of the protective cap 30.

Although not shown, the cap body 100 may be provided with a heat insulating layer made of a heat insulating material in order to more stably maintain the driving temperature of the gas sensor element 20. The heat insulating layer may be partially or entirely covered with at least one of the inner surface and the outer surface of the cap body 100.

The reinforcing frame 220 protrudes from the top of the flange 210 toward the wall of the cap body 100. The reinforcing frame 220 is buried in the wall of the cap body 100 to structurally reinforce the cap body 100 and to couple the cap body 100 and the mounting frame 200 together.

The reinforcing frame 220 may be embedded in the wall of the cap body 100 by insert injection molding. The reinforcing frame (200) is provided with a fitting hole (222). At least one or more engagement holes 222 are provided. Since the synthetic resin composing the cap body 100 is filled in the engagement hole 222 by the engagement hole 222, the cap body 100 and the reinforcement frame 220 are structurally and firmly coupled to each other. Convex projections or concave grooves may be applied instead of the engagement holes 222, depending on the operating conditions and the like.

4, the cap body 100 is provided with gas inlet / outlet passages 110 and 120 for communicating the element accommodating space 105 with the outside of the cap body 100. The gas inlet and outlet passages 110 and 120 may be disposed at an upper portion of the cap body 100.

The gas inlet and outlet passages 110 and 120 include a first passage 110 and a second passage 120. The first passage 110 is formed to communicate with the element accommodating space 105. The second passage 120 includes a first hole 122 communicating with the first passage 110 and a second hole 124 communicating the first hole 122 with the exterior of the cap body 100 do. Of course, the first hole 122 extends from the first passage 110, and the second hole 124 extends from the first hole 122.

The first hole (122) extending from the first passage (110) is formed to have a larger cross sectional area than the first passage (110). Thus, a stepped surface (first stepped surface) is formed between the first passage 110 and the first hole 122. The second hole 124 extending from the first hole 122 is formed so as to have a larger cross sectional area than the first hole 122 and is also provided between the first hole 122 and the second hole 124, (Second-stage difference surface) is formed.

A first gas permeable member 42 is attached to the stepped surface (first stepped surface) between the first passage 110 and the first hole 122. The second gas permeable member 44 is attached to the step difference surface (second step difference surface) between the first hole 122 and the second hole 124. [ The first gas permeable member 42 and the second gas permeable member 44 may be a gas permeable film, a nonwoven fabric, or the like.

The water permeation suppressing member may be applied instead of the first gas permeable member 42 depending on the operating conditions and the like. Alternatively, the moisture permeation suppressing member may be applied instead of the second gas permeable member 44. Alternatively, the water permeation suppressing member may be laminated to at least one of the first gas permeable member 42 and the second gas permeable member 44 so as to be applied together. The moisture permeation inhibiting member may be a functional film that has permeability for gas but can inhibit permeation for moisture.

According to the stepped surface between the first passage 110 and the first hole 122 and the stepped surface between the first hole 122 and the second hole 124, the first gas permeable member 42 Permeation suppressing member) and the second gas permeable member 44 (or the moisture permeation suppressing member) can be ensured, whereby the first gas permeable member 42 and the second gas permeable member 44 The member 44 can be easily attached.

Since the second hole 124 allows the second gas permeable member 44 (and / or the moisture permeation inhibiting member) to be accommodated, it is difficult to access the second gas permeable member 44, It is possible to prevent the permeable member 44 from being damaged or dropped by an external force.

Moisture is introduced into the element accommodating space 105 or a gas other than the gas to be measured is introduced into the first hole 122 in which both openings are blocked by the first gas permeable member 42 and the second gas permeable member 44, A filter 46 for preventing gas from entering the element accommodating space 105 is accommodated. The filter 46 may be in the form of a powder, a molded body, or a paste.

6 is a cross-sectional view showing a gas sensor package according to a second embodiment of the present invention. 6, the gas sensor package according to the second embodiment of the present invention is similar to the gas sensor package according to the first embodiment of the present invention, And reinforcement frame 220 are different.

The reinforcement frame 220 is protruded at a predetermined angle with respect to the vertical direction and buried in the wall of the cap body 100.

An external force acts on the cap body 100 and the mounting frame 200 in a direction in which the cap body 100 and the mounting frame 200 are spaced apart from each other, It is possible to prevent the mounting frame 100 and the mounting frame 200 from being separated from each other.

The reinforcing frame 220 may be formed in a twisted shape or may be curved in order to maximize the separation preventing effect of the cap body 100 and the mounting frame 200 due to the configuration in which the reinforcing frame 220 is inclined with respect to the vertical direction Or the like. Alternatively, a plurality of reinforcing frames 220 may be provided, and all of them may be formed to be inclined inward or outward.

The engaging hole 222 for preventing the separation of the cap body 100 from the mounting frame 200 is formed by the reinforcing frame 220 ).

7 is a perspective view showing a gas sensor package according to a third embodiment of the present invention. As shown in Fig. 7, the gas sensor package according to the third embodiment of the present invention is different from the gas sensor package according to the first embodiment or the second embodiment of the present invention in other constructions and operations Only the constitution of the protective cap 30A is different from that of the protective cap 30A. The differences are as follows.

The protective cap 30A covering the gas sensor element has a lower end opened and an element accommodating space (refer to reference numeral 105 in FIG. 4 and FIG. 6) inside, and a cap body and a heat insulating layer 230 coated on the cap body .

The gas sensor package according to the third embodiment of the present invention has a cap body made of metal. The cap body of the metal is soldered to the lower end of the main board 10. For ease of soldering operation, the cap body is provided along the circumferential direction of the cap body at the lower end thereof to have a flange (annular ring-shaped structure according to Fig. 7) structure constituting the bottom of the protective cap 30A .

The heat insulating layer 230 serves to reduce the influence of a temperature change outside the protective cap 30A on the gas sensor element in the protective cap 30A and may be made of a heat insulating material or a heat resistant material such as a synthetic resin or a ceramic, It may be made of a larger material. The heat insulating layer 230 may be partially or wholly covered with at least one of the inner surface and the outer surface of the cap body.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Further, the technical ideas described in the embodiments of the present invention may be performed independently of each other, or two or more may be implemented in combination with each other.

10: main substrate
20: Gas sensor element
30, 30A: Protective cap
42: first gas permeable member
44: second gas permeable member
46: Filter
100: cap body of synthetic resin
105: element accommodating space
110: first passage
120: second passage
122: first hole
124: Second hole
200: Metal mounting frame
210: Flange
220: reinforcement frame
230: insulating layer

Claims (7)

A printed board; A gas sensor element mounted on the printed board and electrically connected to the wiring of the printed board; And a protective cap covering the gas sensor element and shielding the gas sensor element from the outside,
The cap includes a cap body having a lower end thereof opened and having an element accommodating space for accommodating the gas sensor element therein; And a flange which is provided along the lower end of the cap body at the lower end of the cap body and is made of metal and the entire lower surface is bonded to the printed board by soldering,
Wherein the cap body comprises a material having a heat capacity greater than that of the metal,
Gas sensor package. The method according to claim 1,
Wherein the protective cap further comprises at least one reinforcing frame protruding from the top of the flange toward the wall of the cap body and embedded in the wall to be embedded in the wall.
Gas sensor package. The method of claim 2,
Wherein the reinforcement frame is buried in the wall in a state inclined with respect to the vertical direction,
Gas sensor package. The method according to claim 2 or 3,
Wherein the reinforcing frame is provided with at least one of a hole, a projection and a groove for structural coupling between the wall and the reinforcing frame,
Gas sensor package. The method according to any one of claims 1 to 3,
The cap body is provided with a gas inlet / outlet passage for communicating the element accommodating space with the outside,
Wherein the gas inlet / outlet passage includes: a first passage communicating with the element accommodating space; And a second passage extending from the first passage and communicating with the outside,
The second passage includes: a first hole extending from the first passage; And a second hole extending from the first hole,
Wherein a cross-sectional area of the first hole is larger than that of the first passage, and a cross-sectional area of the second hole is larger than that of the first hole, and between the first passage and the first hole and between the first hole and the second hole A first stage surface and a second stage surface are provided, respectively,
Wherein the first gas permeable member and the second gas permeable member are attached to the first stepped surface and the second stepped surface, respectively, and both openings are blocked by the first gas permeable member and the second gas permeable member, In the first hole,
Gas sensor package. The method according to any one of claims 1 to 3,
Wherein the cap body is made of at least one selected from a synthetic resin having a heat capacity greater than that of a metal and ceramic,
Gas sensor package. The method according to any one of claims 1 to 3,
Wherein the cap body includes a coating layer made of a material having a heat capacity greater than that of metal,
Gas sensor package.

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