JP2643029B2 - Semiconductor pressure sensor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a semiconductor pressure sensor,
In particular, it relates to a small and inexpensive semiconductor pressure sensor having a highly accurate temperature compensation function.

[0002]

FIG. 3 is a sectional view showing a conventional semiconductor pressure sensor. In the figure, a semiconductor pressure sensor (hereinafter, referred to as a pressure sensor) (1) has a semiconductor pressure sensor chip (hereinafter, referred to as a pressure sensor chip) for converting pressure into an electric signal (2) fixed to a stem (4). , Packaged with a cap (3) . A diaphragm (5) is formed on the back surface of the portion of the pressure sensor chip (2) where the IC chip (not shown) is provided. Diaphragm
(5) is a thin portion formed by etching the back surface of the pressure sensor chip (2), and a pressure sensing bridge (not shown) is formed on the surface of the pressure sensor chip (2). The pressure sensor chip (2) is supported by a pedestal (6), and the pedestal (6) is fixed to the stem (4) by an adhesive (7). In the center of the stem (4), a diaphragm
A pressure introduction pipe (8) leading to (5) is provided. Outside the pressure introducing pipe (8), a sensor lead (10) connected to a pressure sensor chip (2) via a wire (9) has a stem.
It is fixed to (4). The inside of the pressure sensor (1) covered with the chap (3) is a vacuum as a reference pressure chamber (11).

FIG. 4 is a perspective view showing a state in which the pressure sensor (1) is mounted on a thick film substrate (13) by a support base (12), and FIG. 5 is a rear view thereof. In these figures, an operational amplifier IC (14) for amplifying the output of the pressure sensor (1) is provided on the back surface of the thick film substrate (13). Pressure sensor
The output from (1) is connected to an operational amplifier IC (14) and the like by a sensor lead (10) and the like. Also, thick film substrates
On the surface of (13), a resistor (1) for adjusting electric characteristics is provided.
5) is formed, and a clip lead (16) is provided on the periphery of the thick film substrate (13).

The conventional pressure sensor (1) is constructed as described above, and when pressure is applied from a pressure introducing pipe (8), a diaphragm formed on the back surface of a pressure sensor chip (2) in the pressure sensor (1). Stress is applied to (5) and the pressure sensor chip
(2) An output signal corresponding to the pressure value is generated from the pressure sensing bridge on the surface. This output signal is the operational amplifier IC (14)
To obtain the final output.

[0005]

The above-described pressure sensor (1) has a problem that the number of parts is large and the product becomes large. Further, since the temperature compensation function of the output is provided in the operational amplifier IC (14), the temperature compensation becomes insufficient because the pressure sensor chip (2) and the operational amplifier IC (14) are arranged apart from each other. And so on. The present invention has been made in order to solve such a problem, and an object of the present invention is to provide a pressure sensor which enables highly accurate temperature compensation and is downsized.

[0006]

According to a first aspect of the present invention, a semiconductor pressure sensor device includes a diaphragm for converting pressure into stress, a strain gauge for converting stress of the diaphragm into an electric signal, and an output of the strain gauge. A semiconductor pressure sensor chip integrally formed with an integrated circuit for amplifying the temperature and compensating for temperature, a pedestal supporting the semiconductor pressure sensor chip and forming a reference pressure chamber with the semiconductor pressure sensor chip, The main body accommodating the pressure sensor chip and the pedestal inside and the lid having the opening are joined together.
When configured packages are embodied, held between the main body and the lid
And one end is electrically connected to the semiconductor pressure sensor chip, and the other end is bent.
And a sensor lead extending opposite to the opening side of the package and supporting the package on a substrate. Further, a semiconductor pressure sensor device according to a second aspect of the present invention, in the first aspect, includes a resistor for adjusting an electrical characteristic of the semiconductor pressure sensor chip on a back surface of the substrate on which the package is mounted. Things.

[0007]

In the present invention, the temperature of the strain gauge and the integrated circuit having the function of compensating for the temperature error with respect to the temperature change can be reduced by forming the diaphragm, the strain gauge, and the integrated circuit for signal amplification into one chip. Since they are equal, high-precision temperature compensation is possible. Further, by providing the opening which is the pressure introduction port directly on the package, the pressure introduction path is shortened, the leak of the pressure to be sensed is reduced, and the pressure to be sensed can be measured reliably and stably. . Also, by providing an opening which is a pressure inlet directly in the package and extending a sensor lead for attaching the package to the substrate to a side opposite to the opening of the package,
The sensor lead can be shortened, miniaturization can be realized,
When mounting the package on the substrate, there is no obstacle between the package and the substrate, and the package can be easily assembled. Further, the number of parts is reduced, for example, the conventional two-chip configuration is replaced with a one-chip configuration, the pressure reference chamber is simplified with a pedestal and a chip, and the number of components is reduced. Since the pressure introduction path can be shortened by directly introducing pressure, downsizing and cost reduction can be realized. Also, the package is separated into the main body and the lid.
The pedestal must be
To the sensor lead with one end of the sensor lead
The wire can be connected to the pressure sensor chip.
Therefore, the pedestal must be mounted without the lid
Shields and wires are connected to improve workability.
it can. Also, when joining the lid to the body, the sensor leads
Is also performed at the same time, and the assemblability is improved. Further, since the resistor for adjusting the electrical characteristics of the semiconductor pressure sensor chip is provided on the back surface of the substrate, the resistor is completely exposed, and the electrical characteristics of the semiconductor pressure sensor chip can be easily adjusted.

[0008]

1 is a side sectional view showing a semiconductor pressure sensor (hereinafter referred to as a pressure sensor) (1A) according to an embodiment of the present invention, and FIG. 2 is a perspective view thereof. In these figures, (7) and (9) are exactly the same as those in the conventional pressure sensor (1) described above. IC pressure sensor chip (hereinafter referred to as pressure sensor chip) (2A)
Has integrated a diaphragm (5) that converts pressure into stress, a strain gauge (not shown) that converts this stress into an electric signal, and an integrated circuit that amplifies the output of the strain gauge and performs temperature compensation. Things. Package (17) is a book
The lid (17B) is joined and integrated with the body (17A).
You. Then, pressure is introduced into the lid (17B) as an opening.
A mouth (21) is provided. In addition, sensor leads (19)
Is sandwiched between the main body (17A) and the lid (17B).
The package (17) is formed by joining the (17A) and the lid (17B).
It is fixed to. This sensor lead (19) has one end
Connected to the pressure sensor chip (2) via a wire (9),
The other end is bent to introduce the pressure of package (17)
It extends to the side opposite to the mouth (21) side. The pressure sensor chip (2A) is supported by a pedestal (6A).
A) is attached to the main body (17 ) of the package (17) by the adhesive (7).
A) is fixed. The package (17) is supported on an insulating substrate (18), for example, alumina ceramic, by sensor leads (19) for inputting and outputting signals from the pressure sensor (1A). An external lead, for example, a clip lead (20) for making an electrical connection to an external circuit is provided on the insulating substrate (18). On the other hand, a pressure inlet (21) is provided above the pressure sensor (1A). A reference pressure chamber (vacuum) is provided between the pressure sensor chip (2A) and the pedestal (6A).
(11A) is formed. Further, a resistor (15A) for adjusting the variation in the electrical characteristics of the pressure sensor chip (2A) is provided at a position corresponding to the pressure sensor chip (2A) on the back surface of the insulating substrate (18). Sensor (1A)
Can be further reduced in size.

In the semiconductor pressure sensor configured as described above, when pressure is applied from the pressure inlet (21), the pressure is received on the surface of the pressure sensor chip (2A) in the pressure sensor (1A). Then, an output signal corresponding to the pressure value is generated by the strain gauge due to the stress applied to the diaphragm (5). The output signal of the strain gauge is amplified by an integrated circuit formed in the pressure sensor chip (2A), and further subjected to temperature compensation.

[0010]

As described above, the present invention provides a diaphragm for converting pressure into stress, a strain gauge for converting stress of the diaphragm into an electric signal, and an integrated circuit for amplifying the output of the strain gauge and performing temperature compensation. Since the circuit and the semiconductor pressure sensor chip are integrally formed on one semiconductor pressure sensor chip and the semiconductor pressure sensor chip is housed in the package, the temperature of the diaphragm and the semiconductor piece becomes equal even with a change in temperature, and the temperature of the integrated circuit is reduced. Temperature compensation function is realized with high accuracy,
In addition, the use of a single chip has the effects of reducing the number of parts, reducing the size, and obtaining an inexpensive semiconductor pressure sensor device. In addition, since the pressure reference chamber is formed by the pedestal and the semiconductor pressure sensor chip, the pressure reference chamber can be configured with a simple structure, and the sensor lead extends to the side opposite to the opening of the package. You can shorten the length of the lead, since the only directly setting the opening in the package, from the opening to introduce the sensor pressure directly can be shortened pressure introduction path, it is possible to obtain a semiconductor pressure sensor device size reduction can be achieved It has the effect of being able to.
In addition, since the opening is provided in the package and the sensor lead extends on the opposite side of the opening of the package, there is no obstacle between the package and the substrate when the package is mounted on the substrate, and the assembly workability is improved. There is an effect that a semiconductor pressure sensor device capable of improving the performance can be obtained. Further, since the opening is directly provided in the package, the pressure introduction path can be formed short, the leak of the pressure to be sensed is reduced, and the semiconductor pressure sensor device capable of improving the stability of characteristics can be obtained. Play. In addition,
Cage joins body and lid together to form a package
The sensor lead between the body and the lid
Because it is fixed, before joining the main body and the lid,
The pedestal can be fixed to the main body from the pace using an adhesive.
Connect one end of the saddle and the semiconductor pressure sensor chip with a wire
Can be connected, and even when the lid is
The arm is fixed at the same time, improving the workability of assembly.
Semiconductor pressure sensor device
Play a fruit. Furthermore, since a resistor for adjusting the electrical characteristics of the semiconductor pressure sensor chip is provided on the back surface of the substrate on which the package is mounted, it is possible to obtain a semiconductor pressure sensor device that can simplify the electrical adjustment of the semiconductor pressure sensor chip. This has the effect that it can be performed.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a semiconductor pressure sensor according to one embodiment of the present invention.

FIG. 2 is a perspective view of the pressure sensor shown in FIG.

FIG. 3 is a side sectional view showing a conventional semiconductor pressure sensor.

FIG. 4 is a perspective view of the pressure sensor shown in FIG.

FIG. 5 is a back view of the pressure sensor shown in FIG. 3;

[Explanation of symbols]

1A pressure sensor, 2A pressure sensor chip, 5 diaphragm, 6A pedestal, 7 adhesive, 9 wires, 11
A Reference pressure chamber, 15A resistor, 17 packages, 1
7A main body, 17B lid, 18 insulating substrate, 19 sensor lead, 20 clip lead, 21 pressure inlet.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-191037 (JP, A) JP-A-60-205329 (JP, A) JP-A-62-121030 (JP, A) 78229 (JP, U) Actually open 55-116252 (JP, U)

Claims (2)

(57) [Claims] A semiconductor pressure sensor chip integrally formed with a diaphragm for converting pressure into stress, a strain gauge for converting stress of the diaphragm into an electric signal, and an integrated circuit for amplifying the output of the strain gauge and performing temperature compensation. And a pedestal supporting the semiconductor pressure sensor chip and constituting a reference pressure chamber with the semiconductor pressure sensor chip; and accommodating the semiconductor pressure sensor chip and the pedestal therein.
Body and lid with opening are joined and integrated
And packages, are pinched between the main body and the cover secured to the package
One end is electrically connected to the semiconductor pressure sensor chip, the other end is bent and extends to the side opposite to the opening side of the package, and a sensor lead for supporting the package on a substrate is provided. A semiconductor pressure sensor device characterized by the above-mentioned. 2. A back surface of a substrate on which a package is mounted.
Resistance to adjust the electrical characteristics of the semiconductor pressure sensor chip.
The semiconductor pressure according to claim 1, further comprising an antibody.
Force sensor device.