JPH04131726A - Semiconductor pressure sensor - Google Patents

Abstract

PURPOSE:To reduce the influence of a thermal stress on a soldering part by using a lead terminal having a buckled stress moderating part formed thereon. CONSTITUTION:Near the clip part 43 of a lead terminal 42, a buckled stress moderating part 45 is formed. When the environmental temperature is changed in the mounting position of an engine controller in the state where a semiconductor pressure sensor is mounted on a circuit board, a hybrid circuit board 35 and a socket 46 are thermally expanded to generate a thermal stress in which the socket 46 relatively presses a lead terminal 24 and the hybrid circuit board 35. Then, the stress moderating part 45 of the lead terminal 42 is extended to moderate the thermal stress. Therefore, the stress by thermal stress is prevented from collectively acting on a soldering part 62 which is the joint part between the lead terminal 42 and the circuit board 60 of the engine controller, and the reliability of the soldering part 62 is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the intake air pressure of an internal combustion engine installed in an automobile, etc.
It relates to semiconductor pressure sensors that detect atmospheric pressure, exhaust pressure, etc.

BACKGROUND OF THE INVENTION In recent years, with the tightening of automobile exhaust gas regulations, it is necessary to control automobile engines so that they are always in the best combustion state regardless of their operating conditions.

Therefore, a pressure transducer is used to detect the engine's intake pressure and convert it into an electrical signal to electronically control the amount of fuel supplied, as well as to control ignition timing to maintain optimal combustion conditions. Alternatively, methods that detect changes in atmospheric pressure and perform advanced corrections have been adopted.

Automotive pressure transducers used for such applications are
There is a demand for products with excellent heat resistance and earthquake resistance, and semiconductor gauge type pressure sensors have come to be widely adopted to meet this demand.

Below, we will explain about this type of conventional semiconductor pressure sensor in the fifth section.
This will be explained based on FIGS. 8 to 8.

FIG. 5 is a plan view of a conventional semiconductor pressure sensor, FIG. 6 is a sectional view taken along line I-I in FIG. 5, FIG. 7 is a partially cutaway side view of a conventional semiconductor pressure sensor, and FIG. 1 is a partially cutaway side view showing a state in which a conventional semiconductor pressure sensor is mounted on a circuit board such as an engine controller.

As shown in FIG. 6, in the conventional semiconductor pressure sensor, a pedestal 3 is bonded to a sensor element 2 on which a pressure-sensitive diaphragm 1 is formed by means such as electrostatic bonding, and a metal spacer 4 is attached to the pedestal 3.
It is mounted together with electronic components 6 such as capacitors on a hybrid circuit board 5 via.

Incidentally, the metal spacer 4 and the hybrid circuit board 5 are joined by soldering, adhesive, or other means.

7 is a bonding wire that connects an electrode (not shown) formed on the pressure sensitive diaphragm 1 and the hybrid circuit board 5; 8 is a bonding wire that connects the electrode (not shown) formed on the pressure sensitive diaphragm 1;
This gel is coated to cover the bonding wire 7 and the bonding wire 7.

9 is the pressure sensitive diaphragm 1 and the bonding wire 7
This is a cap attached to the hybrid circuit board 5 so as to cover it, and a hole 10 for pressure intake is formed in the upper surface of the cap.

Further, in FIG. 5, 11 is a plurality of lead terminals attached to the hybrid circuit board 5 for outputting signals from the hybrid circuit board 5, and 14 is a socket attached to the lead terminal 11. It is.

The above hybrid circuit board 5 of these lead terminals 11
A clip portion 12 for attaching the lead terminal 11 to the hybrid circuit board 5 is formed on the side base, and the tip thereof can be easily inserted into an insertion hole 21 of a circuit board 20 of an engine controller or the like to be described later. As in, ■Cut 13. Then, the plurality of lead terminals 1
1, the f terminal shown in Figure 5 is for grounding (GND), and the g
The terminal indicates the power input terminal, the h terminal indicates the sensor output terminal,
The remaining terminals a to el and i to l are characteristic check terminals and terminals that are inserted into a circuit board of the engine controller or the like and serve to hold the actual conductive pressure sensor.

On the other hand, the socket 14 has a substantially convex side surface, and the socket 14 is attached to the hybrid circuit board 5 on the top surface 15 as shown in FIGS. A tapered groove 16 into which a part of the clip portion 12 of the lead terminal 11 is inserted is formed, and from the deepest part of this tapered groove 16 to the bottom surface 17 of the socket 14, the cut portion 13 of the lead terminal 11 is inserted. An insertion hole 18 is formed for this purpose.

Note that 19 in FIGS. 7 and 8 is a moisture-resistant insulation coating agent that is applied to cover the flat surface of the hybrid circuit board 5 to which the sensor element 2 and the like are bonded.

Further, 20 in FIG. 8 is a circuit board, for example, an engine controller, on which a real conductor pressure sensor consisting of the hybrid circuit board 5 to which the socket 13 is attached is mounted, and is exposed from the bottom surface 17 of the socket 14. In order to insert the V-cut portion 13 of the lead terminal 11,
A plurality of insertion holes 21 are formed. Furthermore, 22 is
The soldering that joins the circuit board 20 and the V-cut portion 12 of the lead terminal 11 is a part.

Next, the operation of the conventional semiconductor pressure sensor configured as described above will be explained.

As shown in FIG. 7, when the V-cut portion 13 of the lead terminal 11 is inserted into the insertion hole 18 from the tapered groove 16 of the socket 14 and the socket 14 is mounted on the hybrid circuit board 5, as shown in FIGS. As shown in the figure, lead terminal 1
The first clip portion 12 is brought into contact with the tapered groove 16 of the socket 14.

In this state, the V-cut portion 13 of the lead terminal 11 is exposed from the bottom surface 17 of the socket 14, and as shown in FIG. When inserted, the bottom surface 17 of the socket 14 comes into contact with the substrate surface of the circuit board 20, and the real conductor pressure sensor is stably placed on the circuit board 20.

Therefore, the V of the lead terminal 11 inserted into the insertion hole 21 is
The cut portion 13 is soldered 22 on the back side of the circuit board 20 as shown in FIG. 8, thereby completing the mounting of the semiconductor pressure sensor on the circuit board 20.

Problems to be Solved by the Invention However, in the conventional configuration, the circuit board 20
When the environmental temperature changes at the mounting location of the engine controller etc., thermal expansion occurs between the socket 14 and the hybrid circuit board 5, and the socket 14 is relatively connected to the lead terminal 11 or the hybrid circuit board 5. A thermal stress will be generated that tries to press the substrate 5.

Therefore, this thermal stress concentrates on the soldering portion 22 of the lead terminal 11 to the circuit board 20, causing deterioration of the solder and reducing the reliability of the soldering portion 22.

The present invention is intended to solve the above conventional problems,
The purpose of the present invention is to provide a semiconductor pressure sensor that can reduce the influence of thermal stress on soldering parts and improve its reliability as an automotive electrical component.

Means for Solving the Problems In order to achieve the above objects, the present invention provides a hybrid circuit board on which a sensor element incorporating a temperature compensation circuit and an amplification and filtering circuit is mounted, and a signal from the hybrid circuit board. The structure includes an output lead terminal in which a buckled stress relaxation part is formed, and a socket attached to the lead terminal.

Therefore, according to the present invention, when the semiconductor pressure sensor is mounted on a circuit board of an engine controller, etc., the environmental temperature of the engine controller, etc. changes, and thermal expansion occurs in the hybrid circuit board and the socket. Even if the socket is pushed toward the hybrid circuit board, the force that tends to push the socket toward the hybrid circuit board is alleviated by the stress relief part formed on the lead terminal, so the soldering that connects the lead terminal and the circuit board of the engine controller, etc. Deterioration of the parts due to thermal stress can be prevented.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 to 4.

FIG. 1 is a partially cutaway plan view of a semiconductor pressure sensor according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line J-J in FIG.
FIG. 3 is a cross-sectional view taken along the line -2 in FIG. 1, and FIG. 4 is a partially cut-away side view showing a state in which a semiconductor pressure sensor according to an embodiment of the present invention is mounted on a circuit board of an engine controller or the like. It is.

As shown in FIG. 2, in the semiconductor pressure sensor according to this embodiment, a pedestal 33 is bonded to a sensor element 32 on which a pressure-sensitive diaphragm 31 is formed by means of electrostatic bonding, etc. It is mounted on a hybrid circuit board 35 together with electronic components 36 such as capacitors.

Note that the metal spacer 34 and the hybrid circuit board 3
5 by soldering or by means of adhesive or the like.

37 is a bonding wire that connects an electrode (not shown) formed on the pressure-sensitive diaphragm 31 and the hybrid circuit board 35; 38 is a bonding wire that covers the pressure-sensitive diaphragm 31 and the bonding wire 37; It is a gel that is coated on the surface.

Reference numeral 39 denotes a hybrid circuit board 3 surrounding the pressure sensitive diaphragm 3.1 and the bonding wire 37.
5, and the cap 4 has a pressure intake hole 41 formed in its open upper surface.
0 is attached.

Further, in FIG. 1, 42 indicates the hybrid circuit board 35 mounted on the hybrid circuit board 35.
A plurality of lead terminals 46 for outputting signals from the lead terminals 42 are sockets that are attached to the lead terminals 42.

The above hybrid circuit board 3 of these lead terminals 42
A clip portion 43 for attaching the lead terminal 42 to the hybrid circuit board 35 is formed on the 5-side base, and the tip thereof is inserted into an insertion hole 61 of a circuit board 6o of an engine controller or the like to be described later. ■Cut 44 for ease of use. Furthermore, a buckled stress relaxation section 45 is formed near the clip section 43 of the lead terminal 42 .

Of the plurality of lead terminals 42, the f terminal shown in FIG. 1 is for grounding (GND), the g terminal is a power input terminal, the h terminal is a sensor output terminal, and the remaining terminals a to el and i to l The terminal is a terminal for checking characteristics, and a terminal that is inserted into a circuit board of the engine controller or the like and serves to hold the semiconductor pressure sensor.

On the other hand, the socket 46 has a substantially convex side surface, and has an insertion hole from the top surface to the bottom surface into which the lead terminal 42 is inserted when the socket 46 is mounted on the hybrid circuit board 35. 47 is formed.

As shown in FIGS. 1, 3, and 4, this insertion hole 47 has a large-diameter portion 48 on its upper surface that matches the buckled shape of the stress relaxation portion 450, and its middle part is cut as described above. Part 4
4 is formed as a small diameter portion 49 that can be inserted.

Note that 50 is applied so as to cover the flat surface of the hybrid circuit board 35 on which the sensor element 32 and the like are mounted.
A coating agent for moisture-resistant insulation, and 60 in Fig. 4,
This is a circuit board for an engine controller or the like on which the semiconductor pressure sensor of this embodiment is mounted, and has a plurality of insertion holes 61 into which the cut portions 44 of the lead terminals 42 exposed from the sockets 46 are inserted. Furthermore, 62 is a soldering part that joins the circuit board 60 and the V-cut part 44 of the lead terminal 42.

Next, the operation of the semiconductor pressure sensor of this embodiment with the above configuration will be explained.

First, as shown in FIG. 1, the lead terminal 42 is inserted into the insertion hole 47 of the socket 46, and the socket 46 is mounted on the hybrid circuit board 35. Then, the stress relaxation part 45 of the lead terminal 42 is connected to the large diameter part 48 of the insertion hole 47, and the V cut part 44 of the lead terminal 42 is connected to the small diameter part 4 of the insertion hole 47.
9, and furthermore, the above ■cut part 4
4 becomes exposed from the bottom side of the socket 46.

Here, when the V-cut portion 44 of the lead terminal 42 exposed from the bottom of the socket 46 is inserted into the insertion hole 61 of the circuit board 60 of an engine controller or the like as shown in FIG. The present semiconductor pressure sensor is stably placed on the circuit board 60 in contact with the substrate surface of the board 60.

Therefore, the V of the lead terminal 42 inserted into the insertion hole 61 is
The cut portion 44 is soldered 62 on the back side of the circuit board 60 as shown in FIG. 4, thereby completing the mounting of the semiconductor pressure sensor on the circuit board 60.

By the way, when the present semiconductor pressure sensor is mounted on the circuit board 60, if there is a change in the environmental temperature at the mounting location of the engine controller or the like, thermal expansion will occur in the hybrid circuit board 35 and the socket 46, causing the socket 46 to A thermal stress is generated that tends to press the lead terminals 42 to the hybrid circuit board 35 relatively.

Then, the large diameter portion 48 and the small diameter portion 49 of the insertion hole 47 of the socket 46 are attached to the stress relaxation portion 45 of the lead terminal 42.
The interface between the lead terminal 42 and the lead terminal 42 is pressed relative to each other, and the stress relaxation part 45 of the lead terminal 42 expands, and the expansion of the stress relaxation part 45 relieves the thermal stress. .

Therefore, the stress due to the thermal expansion is prevented from acting concentratedly on the soldering section 62, which is the joint between the lead terminal 42 and the circuit board 60 of the engine controller, etc., and therefore, the soldering This configuration improves the reliability of the section 62.

Effects of the Invention As described above, according to the present invention, there is provided a hybrid circuit board on which a sensor element incorporating a temperature compensation circuit and an amplification/filtering circuit is mounted, and a buckled circuit board that outputs a signal from the hybrid circuit board. The structure includes a lead terminal in which a stress relaxation part is formed, and a socket to be attached to the lead terminal.

Therefore, even if the semiconductor pressure sensor is mounted on a circuit board of an engine controller, etc., and the environmental temperature of the engine controller, etc. changes and thermal expansion occurs between the hybrid circuit board and the socket, the socket will Since the force that tends to push the circuit board toward the circuit board is relieved by the stress relaxation part formed on the lead terminal, the soldering that joins the lead terminal to the circuit board of an engine controller, etc. Deterioration can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view of a semiconductor pressure sensor according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line J-J in FIG.
FIG. 3 is a cross-sectional view taken along the line -2 in FIG. 1, and FIG. 4 is a partially cut-away side view showing a state in which a semiconductor pressure sensor according to an embodiment of the present invention is mounted on a circuit board of an engine controller or the like. , FIG. 5 is a plan view of a conventional semiconductor pressure sensor, and FIG. 6 is a plan view of a conventional semiconductor pressure sensor.
The figures are a sectional view taken along the line I-I in Fig. 5, Fig. 7 is a partially cutaway side view of a conventional semiconductor pressure sensor, and Fig. 8 shows a conventional semiconductor pressure sensor installed on a circuit board of an engine controller, etc. FIG. 3 is a partially cutaway side view showing the mounted state. 32...Sensor element, 35...Hybrid circuit board, 42...Lead terminal, 45...Stress relaxation part, 4
6...Socket.

Claims (1)

[Claims] A hybrid circuit board on which a sensor element incorporating a temperature compensation circuit and an amplification and filtering circuit is mounted; a lead terminal on which a buckled stress relaxation part is formed for outputting a signal from the hybrid circuit board; A semiconductor pressure sensor having a socket attached to the lead terminal.