JP2020094933A - Thermal flowmeter - Google Patents

Abstract

To provide a thermal flowmeter capable of reducing both of a distortion occurring at a semiconductor mounting part of a circuit package and a distortion occurring at connection terminals due to a temperature change.SOLUTION: A thermal flowmeter 1 includes a chip package 5 which is sealed by resin in such a state that a detection part formed at a flow rate detection element 53 and connection terminals 522 are respectively exposed. The chip package 5 includes a lead frame 521 including a plurality of metal materials with different linear expansion coefficients. The lead frame 521 includes: the connection terminals 522 for connecting with the outside; and a semiconductor mounting part 523 at which a semiconductor element is mounted. A metal material forming the semiconductor mounting part 523 has a smaller linear expansion coefficient than that forming the connection terminals 522.SELECTED DRAWING: Figure 8

Description

The present invention relates to a thermal type flow meter.

In Patent Document 1, as a claim 1, "a sensor element for measuring a flow rate of a fluid to be measured, and an LSI electrically connected to the sensor element are provided, and a cavity is formed in a substrate of the sensor element. In a chip package in which a heating resistor is formed in the thin film portion on the cavity through an electric insulating film, the LSI and a chip component for protecting the LSI are mounted on a metal lead frame, The LSI and the lead frame are sealed with a thermosetting resin, one end side of the lead frame projects from the thermosetting resin, and an input/output terminal portion for inputting and outputting a signal to and from the outside, and the drive circuit. And a mounting portion on which the I/O terminal portion is mounted, the input/output terminal portion is formed independently of the mounting portion, and the input/output terminal portion is formed independently of the mounting portion. A terminal that is electrically connected via bonding, and the chip component is a terminal that is integrally formed with the mounting portion and a terminal that is formed independently of the mounting portion. A chip package, which is directly mounted on the lead frame via a conductive adhesive so as to bridge between.

JP, 2017-228798, A

When the above-mentioned conventional chip package is mounted on a printed circuit board (not shown) with solder, there are problems due to conflicting characteristics in selecting the material of the lead frame. For example, considering the thermal strain between the mounting part and electronic components such as LSI and chip components, it is necessary to select a material having a relatively small linear expansion coefficient close to the linear expansion coefficient of these electronic components as the lead frame material. is there. On the other hand, considering the solder strain between the input/output terminal portion and the printed circuit board, it is necessary to select a material having a relatively large linear expansion coefficient close to that of the printed circuit board as the lead frame material.

The present invention has been made in view of the above points, and an object thereof is to reduce the heat generated in the semiconductor mounting portion of the circuit package and the distortion generated in the connection terminal due to temperature change. Type flow meter.

A thermal type flow meter of the present invention which solves the above-mentioned problems includes a lead frame provided with a plurality of metal materials having different linear expansion coefficients, and the lead frame is mounted with a connection terminal for connecting to the outside and a semiconductor element. A semiconductor mounting portion, and the linear expansion coefficient of the metal material forming the semiconductor mounting portion is smaller than that of the metal material forming the connection terminal, and the detection portion and the connection terminal formed on the semiconductor element. It is characterized by comprising a circuit package sealed with a resin so that and are exposed.

According to the present invention, it is possible to provide a thermal type flow meter capable of reducing both the strain generated in the semiconductor mounting portion and the strain generated in the connection terminal due to the temperature change.

Further features related to the present invention will be apparent from the description of the present specification and the accompanying drawings. Further, problems, configurations and effects other than those described above will be clarified by the following description of the embodiments.

The front view of a thermal type flow meter. The rear view of a housing. The right view of the thermal type flow meter. IV-IV sectional view taken on the line of FIG. The front view of the thermal type flow meter which shows a housing transparently. The figure explaining the structure of a cover assembly. The front view of the circuit board with which the chip package and the circuit component were mounted. VIIB-VIIB sectional view taken on the line of FIG. 7A. The VIIC-VIIC sectional view taken on the line of FIG. 7A. FIG. 3 is a schematic diagram illustrating the configuration of a chip package. FIG. 3 is a schematic diagram illustrating a configuration of a semiconductor mounting portion and a connection terminal of a chip package. The XX sectional view taken on the line of FIG. The figure which shows the state which the chip package mounted in the circuit board typically.

The modes for carrying out the invention (hereinafter, examples) described below solve various problems demanded as actual products, and particularly as a detection device for detecting a physical quantity of intake air of a vehicle. It solves various problems desirable for use and exerts various effects. One of the various problems that the following examples are solving is the content described in the column of the problems to be solved by the invention described above, and one of the various effects that the following examples have, It is the effect described in the column of the effect of the invention. Various problems solved by the following examples and various effects achieved by the following examples will be described in the description of the following examples. Therefore, the problems and effects solved by the embodiments described in the following embodiments are also described in the contents other than the contents of the problems to be solved by the invention and the effects of the invention.

In each of the following embodiments, the same reference numeral indicates the same configuration even if the drawing numbers are different, and has the same effect. With respect to the configurations already described, only the reference symbols are attached to the drawings, and the description may be omitted.

1 to 3 are views showing the appearance of a thermal type flow meter, FIG. 1 is a front view of the thermal type flow meter, FIG. 2 is a rear view of a housing, and FIG. 3 is a right side of the thermal type flow meter. FIG.
The thermal type flow meter 1 of this embodiment is a physical quantity detection device for detecting a physical quantity of intake air taken into an internal combustion engine of an automobile, and is mounted on an intake pipe of the internal combustion engine.

The thermal type flow meter 1 is used by being inserted into the intake pipe through a mounting hole provided in a passage wall of the intake pipe. The thermal type flow meter 1 includes a housing 2 and a cover 3 attached to the housing 2. The housing 2 is configured by injection molding a synthetic resin material, and the cover 3 is configured by a plate-shaped member made of a conductive material such as an aluminum alloy. The cover 3 is formed in a thin plate shape and has a wide flat cooling surface.

The housing 2 has a flange 21 for fixing the thermal type flow meter 1 to the intake pipe, a connector 23 protruding from the flange 21 and exposed to the outside from the intake pipe for electrical connection with an external device, and a flange. The measuring unit 22 extends from 21.

The measurement unit 22 has a thin and long shape that extends straight from the flange 21, and has a wide front surface 221 and a rear surface 222, and a pair of narrow side surfaces 223 and 224. The measurement unit 22 projects from the inner wall of the intake pipe toward the center of the passage of the intake pipe when the thermal flow meter 1 is attached to the intake pipe. The front surface 221 and the back surface 222 are arranged parallel to each other along the central axis of the intake pipe, and the side surface 223 of the narrow side surfaces 223, 224 of the measurement portion 22 on the one short side of the measurement portion 22 serves as the intake pipe. The side surface 224 on the other side in the short-side direction of the measurement unit 22 is disposed so as to face the upstream side and faces the downstream side of the intake pipe. With the thermal flow meter 1 attached to the intake pipe, the tip of the measurement unit 22 is the lower surface 225.

In the thermal type flow meter 1, since the sub passage inlet 201 is provided at the tip of the thin and long measuring portion 22 extending from the flange 21 toward the center of the intake pipe, the measurement error related to the decrease in the flow velocity near the inner wall surface. Can be reduced. Further, in the thermal type flow meter 1, not only the sub passage inlet 201 is provided at the tip of the measuring portion 22 extending from the flange 21 toward the center of the intake pipe, but also the first outlet 202 and the second passage 202 of the sub passage are provided. Since the outlet 203 is also provided at the tip of the measurement unit 22, the measurement error can be further reduced.

The thermal flow meter 1 has a shape in which the measuring unit 22 extends long along the axis extending from the outer wall of the intake pipe toward the center, but the widths of the side surfaces 223 and 224 are narrow as shown in FIG. Is done. Thereby, the thermal type flow meter 1 can suppress the fluid resistance to a small value with respect to the gas to be measured.

The measuring unit 22 of the thermal type flow meter 1 is inserted inside from a mounting hole provided in the intake pipe, the flange 21 of the thermal type flow meter 1 is brought into contact with the intake pipe, and is fixed to the intake pipe with a screw. The flange 21 has a substantially rectangular shape in plan view having a predetermined plate thickness.

As shown in FIGS. 4 and 5, the connector 23 has an external terminal 231 provided therein. The external terminal 231 is a terminal for outputting a physical quantity such as a flow rate or a temperature, which is a measurement result of the thermal type flow meter 1, and a power supply terminal for supplying DC power for operating the thermal type flow meter 1.

The housing 2 is provided with a sub passage groove 210 for forming a sub passage and a circuit chamber 213 for accommodating the circuit board 4. The circuit chamber 213 and the sub-passage groove 210 are recessed in the back surface 222 of the measuring unit 22. The circuit chamber 213 is provided in a region on the upstream side in the flow direction of the gas to be measured in the intake pipe on the one side in the lateral direction (side surface 223 side). Then, the sub passage groove 210 is located in a region on the distal end side (lower surface 225 side) in the longitudinal direction of the measurement unit 22 with respect to the circuit chamber 213 and a position downstream of the circuit chamber 213 in the flow direction of the measured gas in the intake pipe. It is provided over the region on the other side in the lateral direction (side surface 224 side).

The sub passage groove 210 forms a sub passage in cooperation with the cover 3. The sub-passage groove 210 that forms the sub-passage has a first sub-passage groove 211 and a second sub-passage groove 212 that branches in the middle of the first sub-passage groove 211. The first sub-passage groove 211 has a sub-passage inlet 201 that opens to the side surface 223 on one side in the short-side direction of the measuring section 22 and a first outlet 202 that opens to the side surface 224 on the other side in the short-side direction of the measuring section 22. It is formed so as to extend along the lateral direction of the measuring unit 22 over the space. The first sub-passage groove 211 constitutes a first sub-passage that takes in the measurement gas flowing in the intake pipe from the sub-passage inlet 201 and returns the taken measurement gas from the first outlet 202 to the intake pipe. The first sub passage extends from the sub passage inlet 201 along the flow direction of the gas to be measured in the intake pipe and is connected to the first outlet 202.

The second sub passage groove 212 is branched at an intermediate position of the first sub passage groove 211, is bent toward the base end side (flange side) of the measurement unit 22, and extends along the longitudinal direction of the measurement unit 22. Exists Then, the base end portion of the measurement unit 22 bends toward the other short-side direction (side surface 224 side) of the measurement unit 22, makes a U-turn toward the tip end of the measurement unit 22, and again in the longitudinal direction of the measurement unit 22. Extend along. The first outlet 202 is bent toward the other side in the lateral direction of the measuring unit 22, and is provided so as to be continuous with the second outlet 203 that opens to the side surface 224 on the other side in the lateral direction of the measuring unit 22. Has been. The second outlet 203 is arranged so as to face the downstream side in the flow direction of the measured gas in the intake pipe. The second outlet 203 has an opening area that is almost the same as or slightly larger than that of the first outlet 202, and is formed at a position adjacent to the first outlet 202 on the proximal side in the longitudinal direction of the measuring unit 22.

The second sub-passage groove 212 constitutes a second sub-passage through which the measured gas branched and flown from the first sub-passage passes and is returned from the second outlet 203 to the intake pipe. The second auxiliary passage has a path that reciprocates along the longitudinal direction of the measuring unit 22. That is, the second sub-passage is branched in the middle of the first sub-passage, extends toward the base end side of the measurement unit 22, is folded back at the base end side of the measurement unit 22, and is then folded back. A path that extends toward the tip end side and is connected to a second outlet 203 that is located downstream of the auxiliary passage inlet 201 in the flow direction of the measured gas in the intake pipe and that faces the downstream side in the flow direction of the measured gas. Have. The flow rate detection element 53 is arranged at an intermediate position in the second sub passage groove 212. The second sub passage groove 212 can secure a longer passage length of the second sub passage, and can reduce the influence on the flow rate detection element 53 when pulsation occurs in the intake pipe.

According to the above configuration, the sub passage can be formed along the extending direction of the measuring unit 22, and the length of the sub passage can be sufficiently long. As a result, the thermal type flow meter 1 can include a sub passage having a sufficient length. Therefore, the thermal type flow meter 1 can suppress the fluid resistance to a small value and can measure the physical quantity of the gas to be measured with high accuracy.

The first sub-passage groove 211 extends from the sub-passage inlet 201 to the first outlet 202 along the lateral direction of the measuring unit 22, and therefore enters the sub-passage inlet 201 into the first sub-passage. Foreign matter such as dust can be discharged as it is from the first outlet 202. Therefore, it is possible to prevent foreign matter from entering the second auxiliary passage and prevent the flow rate detecting element 53 in the second auxiliary passage from being affected.

Regarding the sub-passage inlet 201 and the first outlet 202 of the first sub-passage groove 211, the sub-passage inlet 201 has a larger opening area than the first outlet 202. By making the opening area of the sub-passage inlet 201 larger than that of the first outlet 202, the measured gas that has flowed into the first sub-passage can be reliably transferred to the second sub-passage that branches in the middle of the first sub-passage. Can be guided.

FIG. 6 is a diagram illustrating the configuration of the cover assembly.
The cover assembly includes a cover 3 and a circuit board 4 on which a chip package (circuit package) 5 is mounted. The cover 3 is made of a conductive material made of metal such as aluminum alloy or stainless alloy. The cover 3 is made of a flat plate member having a size that covers the back surface 222 of the measuring unit 22, and is fixed to the measuring unit 22 with an adhesive. The cover 3 covers the circuit chamber 213 of the measurement unit 22 and forms a sub-passage in cooperation with the first sub-passage groove 211 and the second sub-passage groove 212 of the measurement unit 22. The cover 3 is electrically connected to the ground by interposing a conductive intermediate member between the cover 3 and a predetermined connector terminal, and has a static elimination function.

A circuit board 4 on which a chip package 5 is mounted is fixed to the back surface of the cover 3. The circuit board 4 has a board body 41 made of, for example, a printed board. The substrate body 41 has a rectangular shape extending along the longitudinal direction of the measuring unit 22. The chip package 5 is fixed to the circuit board 4 at a central position in the longitudinal direction of the circuit board 4 in a state of protruding laterally from the end along the lateral direction of the circuit board 4. The package body 51 of the chip package 5 includes a base end portion 512 in which at least a part in the thickness direction is accommodated in the accommodation portion 412 of the circuit board 4, and an end portion of the circuit board 4 along the lateral direction of the circuit board 4. It has a tip portion 511 protruding laterally from.

The cover assembly accommodates the circuit board 4 in the circuit chamber 213 and extends the chip package 5 between the sub passage and the circuit chamber 213 by attaching the cover 3 to the back surface 222 of the housing 2. Thus, the tip portion 511 of the package body 51 can be arranged in the sub passage. A flow rate detection element 53 is provided at the tip portion 511 of the package body 51, and the detection section of the flow rate detection section is arranged to be exposed in the second sub passage groove 212.

7A is a front view of a circuit board on which a chip package and circuit components are mounted, FIG. 7B is a sectional view taken along line VIIB-VIIB of FIG. 7A, and FIG. 7C is a sectional view taken along line VIIC-VIIC of FIG. 7A.

The circuit board 4 is provided with an accommodating portion 412 for accommodating a part of the chip package 5. As shown in FIG. 7A, the accommodating portion 412 is configured by partially cutting out a portion that is deviated to the one side in the lateral direction at the center of the substrate body 41 in the longitudinal direction (notch portion). Reference numeral 41 has a substantially U shape in a plan view.

As shown in FIGS. 7A, 7B, and 7C, at least a part of the package body 51 in the thickness direction of the chip package 5 is accommodated in the accommodation portion 412 of the circuit board 4. Specifically, the package front surface of the package body 51, which is the base end portion 512 and the surface of the package body 51 on which the flow rate detection element 53 is provided, is accommodated in the accommodation portion 412 of the circuit board 4. ..

In this embodiment, a part of the package body 51 in the thickness direction is housed in the housing portion 412 of the circuit board 4, so that the overall mounting height including the thickness of the chip package 5 and the height of the terminals is suppressed. be able to. As a result, for example, the mounting height can be reduced to the same as that of a small pressure sensor mounted on the circuit board 4 together with the chip package 5. Further, the mounting height of the mounted components can be suppressed to be lower than that in the case where the chip package 5 is mounted on the circuit board 4 in an overlapping manner. Therefore, the height of the measuring unit 22 can be reduced, the thermal flowmeter 1 can be made thin, and the flow resistance in the main passage in the intake pipe can be reduced.

In the present embodiment, the case where a part of the package body 51 in the thickness direction is housed in the housing portion 412 of the circuit board 4 has been described as an example, but the entire package body 51 in the thickness direction is housed. It may be configured to be. With such a configuration, the height of the measuring unit 22 can be further promoted, and the thermal type flow meter 1 can be thinned.

As shown in FIG. 7A, the chip package 5 and electronic components such as the pressure sensor 42 are mounted on the front surface of the circuit board 4. The chip package 5 is provided with a plurality of connecting terminals 522 protruding from the base end portion 512 of the package body 51. By connecting these connecting terminals 522 to the pads 43 of the circuit board 4 by soldering, the circuit board 4 is formed. Is integrally fixed to. The chip package 5 is mounted with a flow rate detection element 53 and an LSI that is an electronic component that drives the flow rate detection element 53.

The base end portion 512 of the chip package 5 is provided with a plurality of connection terminals 522 that project in the direction away from each other along the lateral direction of the package body 51. On the mounting surface 411 of the board body 41 of the circuit board 4, a plurality of pads 43 are separately provided on one side and the other side in the longitudinal direction of the circuit board 4, which are locations facing each other with the accommodating portion 412 interposed therebetween. , The plurality of connection terminals 522 of the chip package 5 are soldered to the respective pads 43. The plurality of connection terminals 522 form a solder fixing portion that solder-fixes the chip package 5 to the circuit board 4.

The chip package 5 is configured by mounting the LSI 54 and the flow rate detecting element 53 on a lead frame 521 and sealing with a thermosetting resin. The chip package 5 has a package body 51 that is resin-molded into a substantially flat plate shape. The package main body 51 has a rectangular shape, extends along the lateral direction of the measuring unit 22, and the base end 512 on one longitudinal side of the package main body 51 is accommodated in the accommodation unit 412 of the circuit board 4. The tip portion 511 on the other longitudinal side of the package body 51 is arranged so as to project from the circuit board 4.

The flow rate detecting element 53 of the chip package 5 is provided so that the detecting portion is exposed in the passage groove 513 formed in the surface of the package body 51. The passage groove 513 extends from the one end in the lateral direction to the end in the other lateral direction of the package body 51 so as to extend along the second auxiliary passage groove 212 in the second auxiliary passage groove 212. Is formed over the entire width of. The flow rate detection element 53 has a diaphragm structure. When the chip package 5 is molded with resin, resin molding is performed by applying an insert piece so that the resin does not flow into the detection portion on the surface of the flow rate detection element 53. In the chip package 5, the flow rate detection element 53 is sealed with resin so that the detection portion of the flow rate detection element 53 is exposed.

The connection terminals 522 of the chip package 5 are provided so as to project in the lateral direction of the package body 51 from the center of the package body 51 in the thickness direction. The connection terminal 522 has a facing surface facing the pad 43 of the circuit board 4, and the position of the facing surface is set at the same height as the mounting surface of the lead frame 521.

The chip package 5 is electrically connected by soldering the plurality of connection terminals 522 provided on the base end portion 512 of the package body 51 to the plurality of pads 43 of the circuit board 4, and is integrated with the circuit board 4. Fixed. The base end portion 512 of the chip package 5 is fixed to the circuit board 4, the tip end portion 511 projects from the circuit board 4, and the chip package 5 is so-called cantilevered with respect to the circuit board 4.

8 is a schematic diagram illustrating the configuration of the chip package, FIG. 9 is a schematic diagram illustrating the configurations of the semiconductor mounting portion and the connection terminal of the chip package, and FIG. 10 is a cross-sectional view taken along line XX of FIG. FIG. 11 is a diagram schematically showing a state in which the chip package is mounted on the circuit board.

The chip package 5 has a structure in which the LSI 54 and the flow rate detection element 53 are mounted on a lead frame 521, and is sealed with resin so that the detection portion of the flow rate detection element 53 and the plurality of connection terminals 522 are exposed. have. The lead frame 521 has a connection terminal 522 for connecting to the outside and a semiconductor mounting portion 523 on which the LSI 54 and the flow rate detection element 53, which are semiconductor elements, are mounted.

The connection terminal 522 is partially exposed from the resin-sealed chip package 5, and is soldered to the pad 43 of the circuit board 4 as shown in FIG. The LSI 54 and the flow rate detection element 53 are adhered to the upper surface of the semiconductor mounting portion 523 by an adhesive layer 55.

The connection terminal 522 and the semiconductor mounting portion 523 are formed independently of each other, and are provided in the same height direction in the package body 51 of the chip package 5, that is, on the same plane, as shown in FIG. They are arranged so as to be lined up by a predetermined distance. The LSI 54 mounted on the semiconductor mounting portion 523 and the connection terminal 522 are electrically connected by a bonding wire 524, and the LSI 54 and the flow rate detection element 53 are electrically connected by a bonding wire 525. It is connected.

The connection terminal 522 and the semiconductor mounting portion 523 are made of metal materials having different linear expansion coefficients. The connection terminal 522 is made of a metal material having a linear expansion coefficient close to that of the circuit board 4, and the semiconductor mounting portion 523 is made of a metal material having a linear expansion coefficient close to that of the LSI 54 and the flow rate detection element 53. Has been done. Regarding the connection terminal 522 and the semiconductor mounting portion 523, the metal material forming the semiconductor mounting portion 523 has a smaller linear expansion coefficient than the metal material forming the connection terminal 522. In other words, the semiconductor mounting portion 523 is made of a metal material having a smaller linear expansion coefficient than the connection terminal 522, and the connection terminal 522 is made of a metal material having a larger linear expansion coefficient than the semiconductor mounting portion 523. Wood is used.

In this example, the linear expansion coefficient α of the copper material forming the connection terminal 522 is 16.5 [ppm/° C.], the linear expansion coefficient α of the solder is 23.0 [ppm/° C.], and the circuit board 4 is used. The linear expansion coefficient α of the glass epoxy printed circuit board is 11.0 to 15.0 [ppm/° C.], and the values are close to each other. The semiconductor mounting portion 523 is made of a 42 alloy (42% Ni-Fe) material in which iron is mixed with nickel, and the connection terminal 522 is made of a copper (Cu) material. The linear expansion coefficient α of the 42 alloy material forming the semiconductor mounting portion 523 is 4.2 [ppm/°C], and the linear expansion coefficient α of the flow rate detection element 53 is 3.0 [ppm/°C], and the values are close to each other. doing.

In the chip package 5 of the present embodiment, by using a plurality of materials having different characteristics such as a linear expansion coefficient as the material of the lead frame 521, the strain generated in the semiconductor mounting portion 523 and the solder strain of the connection terminal 522 are used. To reduce both. The chip package 5 uses a metal material having a linear expansion coefficient close to that of the circuit board 4 for the connection terminal 522, and uses a metal material having a linear expansion coefficient close to that of the LSI 54 and the flow rate detection element 53 as a semiconductor. It is used for the mounting unit 523. Therefore, it is possible to reduce the difference in the linear expansion coefficient between the circuit board 4 and the connection terminal 522 and reduce the difference in the linear expansion coefficient between the LSI 54 and the flow rate detection element 53 and the semiconductor mounting portion 523. Therefore, both the stress generated between the circuit board 4 and the connection terminal 522 due to the temperature change and the stress generated between the LSI 54 and the flow rate detection element 53 and the semiconductor mounting portion 523 are reduced, and the stress is generated in the semiconductor mounting portion 523. Both the strain and the strain generated in the connection terminal 522 can be reduced.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It is something that can be changed. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Furthermore, it is possible to add/delete/replace other configurations with respect to a part of the configurations of the respective embodiments.

1 Thermal Type Flow Meter 5 Chip Package 53 Flow Rate Detection Element 521 Lead Frame 522 Connection Terminal 523 Semiconductor Mounting Section

Claims (5)

A lead frame provided with a plurality of metal materials having different linear expansion coefficients,
The lead frame has a connection terminal for connecting to the outside, and a semiconductor mounting portion on which a semiconductor element is mounted,
The linear expansion coefficient of the metal material forming the semiconductor mounting portion is smaller than that of the metal material forming the connection terminal,
A thermal type flow meter, comprising: a circuit package sealed with a resin so that a detection part formed on the semiconductor element and the connection terminal are exposed. The thermal flow meter according to claim 1, wherein the connection terminal is formed independently of the semiconductor mounting portion and is electrically connected to the semiconductor element via a bonding wire. The thermal type flow meter according to claim 1, wherein the semiconductor mounting portion and the connection terminal are provided in the same height direction. The thermal type flow meter according to claim 1, wherein the connection terminal is a copper material, and the semiconductor mounting portion is a 42 alloy material. The thermal flow meter according to claim 1, wherein the connection terminal is soldered to a circuit board.

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