JPH10332506A - Semiconductor pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the semiconductor pressure sensor with high reliability. SOLUTION: A semiconductor sensor chip 1 is mounted on a ceramic substrate 10. The semiconductor sensor chip 1 has piezoresistance formed on its pressure receiving diaphragm formed by forming a recessed part in the semiconductor substrate. The semiconductor sensor chip 1 and a bonding wire W are shielded by a light shield lid 40 from external light. The light shield lid 40 is adhered to the ceramic substrate 10 with an adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor pressure sensor.

[0002]

2. Description of the Related Art A conventional semiconductor pressure sensor is, for example, shown in FIG.
As shown in FIG. 4 and FIG. 25, a semiconductor sensor chip 1 in which a piezoresistor is formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate is a ceramic substrate 1.
0 (printed board). Here, the electrodes (not shown) on the surface of the semiconductor sensor chip 1 and the electrodes 13 formed on the ceramic substrate 10 are connected by bonding wires W made of fine aluminum wires. Also,
An output amplifier circuit for amplifying the output (differential output) of the semiconductor sensor chip 1 is provided on the ceramic substrate 10. Here, the output amplifier circuit is a ceramic substrate 10
, And thick film resistors R ₁ and R ₂ for trimming formed on the ceramic substrate 10 by firing. The thick film resistors R ₁ and R ₂ are formed by firing a resistor paste printed by screen printing, and R ₃ and R _{4 in} FIG. 24 constitute a part of the output amplifier circuit. Thick film resistance.

The ceramic substrate 10 on which the semiconductor sensor chip 1 and the like are mounted is housed in a body 20 made of, for example, resin having an open surface as shown in FIG. Note that a cover (not shown) is attached to the body 20. Also,
Reference numeral 21 in FIG. 24 denotes a pressure introducing hole 24 communicating with the recess provided in the semiconductor sensor chip 1 and the hole 11 formed in the ceramic substrate 10.

A plurality of metal terminals 22 are formed on the body 20 at the same time, and the output amplifying circuit uses a conductive paste (for example, silver paste), solder, or the like on the terminals 22 provided on the body 20. Connected by Here, the terminal 22 constitutes a terminal for taking out the output of the output amplifier circuit to the outside, a terminal for supplying power to the output amplifier circuit, and the like.

Further, as another semiconductor pressure sensor,
As shown in FIGS. 27 and 28, the semiconductor sensor chip 1
In some cases, a glass pedestal 5 is interposed between the glass pedestal 5 and the ceramic substrate 10. Here, a hole 6 communicating with the recess 3 of the semiconductor sensor chip 1 and the pressure introducing hole 24 is formed in the glass pedestal 5. In the semiconductor sensor chip 1, a piezoresistor is formed on the main surface of a pressure receiving diaphragm formed by providing a recess 3 in a semiconductor substrate, and is connected to a conductive portion (electrode) of a ceramic substrate 10 by a bonding wire W. The surface is coated with a silicone resin 7. C in FIG. 28 is a capacitor constituting a part of the output amplifier circuit. FIG. 27 (a)
Reference numeral 33 denotes an adhesive for fixing the ceramic substrate 10 to the body 20, reference numeral 34 denotes a conductive paste for establishing conduction between the conductive portion of the ceramic substrate 10 and the terminal 22, and reference numeral 100 denotes a conductive paste. Is a frame for integrally molding the terminal 22 with the body 20.

A pressure introducing pipe 21 having a pressure introducing hole 24 communicating between the inside and the outside of the body 20 projects from the bottom surface of the body 20, and a hole 11 is also formed in the ceramic substrate 10 so that a semiconductor sensor chip is formed. The pressure from the pressure introduction hole 24 of the pressure introduction pipe is transmitted to the first pressure receiving diaphragm. Further, a case is constituted by the body 20 and a cover 60 adhered and fixed to the body 20 and covering the semiconductor sensor chip 1 and the ceramic substrate 10. The body 20 includes the semiconductor sensor chip 1 and the cover 6.
An air introduction hole 26 is formed which communicates a space between 0 and the outside of the case.

[0007] In this type of semiconductor pressure sensor, variations in the magnitude (sensitivity) of the output with respect to the pressure of the sensor itself,
Since the change in the characteristics with respect to the ambient temperature is large, it is often difficult to control the characteristics to the required accuracy. For this reason, the output of the sensor is measured once after assembly, and the resistance values of the thick film resistors R ₁ and R ₂ for trimming on the ceramic substrate 10 are calculated (hereinafter, referred to as predetermined values). By trimming with a laser, the characteristics are driven to a required range or a target value. There are roughly two types of trimming methods. One is a resistor trimming for obtaining the resistance value of the thick film resistor and trimming the thick film resistors R ₁ and R ₂ so as to reach the predetermined value, and the other is an output. Function trimming is to trim the thick film resistors R ₁ and R ₂ while monitoring the output voltage of the amplifier circuit to drive the output voltage to a predetermined range or a predetermined value.

[0008]

The thick film resistor R
_1, the trimming of R _2, so-called laser trimming device is used. Here, the laser trimming device is
Generally, in order to perform high-precision trimming of the small-sized thick-film resistors R ₁ and R ₂ , the ceramic substrate 10 is aligned using an image recognition device or the like. This type of alignment is performed by detecting an alignment mark formed in advance on the surface of the ceramic substrate 10 on which the thick film resistors R ₁ and R ₂ are formed (hereinafter, this surface is referred to as the front surface of the ceramic substrate 10). Therefore, it is necessary to irradiate light to the front surface of the ceramic substrate 10 to brighten the entire front surface of the ceramic substrate 10. In addition,
Even when an image recognition device is not used, it is necessary to perform manual alignment while looking at a monitor, so that the front surface of the ceramic substrate 10 is often irradiated with light.

However, in the semiconductor pressure sensor, when the semiconductor sensor chip 1 is irradiated with light, the semiconductor sensor chip 1 itself generates photovoltaic power, which is amplified by an output amplifier circuit. Even photovoltaic power is taken out as a large output voltage. For this reason, the error especially when performing the fact trimming becomes large,
In some cases, trimming was not possible. Similarly, there is a problem that extra current is generated even in resistance trimming, and the trimming accuracy is reduced.

In order to solve this kind of problem, conventionally,
After the accurate alignment is completed in the image recognition device, the illumination for the alignment is turned off, and then trimming is performed using a laser beam. The service life is shortened, the maintenance cost of the laser trimming device is increased, and as a result, the manufacturing cost including the maintenance cost of the manufacturing device is increased.

In the conventional semiconductor pressure sensor, the ceramic substrate 10 is used for trimming in consideration of the stability and reliability of the trimming thick film resistor for adjusting the output voltage, temperature characteristics, amplification degree, etc. of the sensor. And a thin aluminum wire is used as the bonding wire W. This is because the ceramic substrate 10 has a high thermal conductivity. In general, when a highly reliable gold wire is used as a bonding wire, the temperature of the bonding pad (electrode) is raised to about 150 ° C. This is because the substrate 10 needs to be heated to a higher temperature. That is, in addition to the semiconductor sensor chip 1, the ceramic substrate 10 has an amplification I / O such as an operational amplifier.
Since C30 is present, bonding at such a high temperature cannot be performed, and wire bonding is performed using an aluminum thin wire that can be bonded at a lower temperature than a gold wire.

However, aluminum thin wires have a problem that they are more susceptible to corrosion than gold wires, and their reliability is low in a high-temperature, high-humidity environment. In addition, in either case of a gold wire or an aluminum thin wire, there is a problem that the bonding wire W may be deformed and disconnected due to vibration or impact. Further, in the semiconductor pressure sensor of the conventional configuration, when the detected pressure becomes a 0.2 kg / cm ² or less fine pressure, the sensitivity of the semiconductor sensor chip 1 is lowered, the pressure of 0.2 kg / cm ² or less If detection is desired, it is necessary to increase the amplification gain of the output amplifier circuit. Therefore, the drift of the offset voltage of the amplification IC 30 cannot be ignored as the drift of the sensor. In particular, under high humidity, offset drift of the amplification IC 30 appears remarkably. Although a silicon gel 90 is sealed around the ceramic substrate 10 as in the conventional configuration shown in FIG. 26, the silicon gel 90 has high moisture permeability, and thus has little effect at high temperature and high humidity. The frame 110 in FIGS. 26 and 27 is a member for preventing the silicon gel 90 from flowing into the semiconductor sensor chip 1.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a highly reliable semiconductor pressure sensor.

[0014]

In order to achieve the above object, according to the present invention, there is provided a semiconductor sensor chip in which a piezoresistor is formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate; A substrate on which the semiconductor sensor chip is mounted and on which an amplifier circuit for amplifying the output of the semiconductor sensor chip is formed; bonding wires connecting the electrodes of the semiconductor sensor chip and the electrodes of the ceramic substrate; A trimming resistor for adjusting the output, wherein the semiconductor sensor chip is shielded from light by a light-blocking member, so that the semiconductor sensor chip is not irradiated with external light when trimming is performed. Therefore, stable characteristic adjustment is possible,
Since the sensitivity can be increased, the reliability can be increased. In addition, since trimming can be performed with high precision without being affected by the illumination for positioning the substrate, the number of times of turning on and off the illumination for alignment can be reduced, and the life of the illumination for alignment is prolonged. Manufacturing costs including maintenance costs can be reduced.

According to a second aspect of the present invention, in the first aspect, the light-shielding member is a box-shaped light-shielding cover that covers at least the semiconductor sensor chip and the bonding wire, has a ventilation hole, and is open on one side. It is possible to suppress the generation of the photovoltaic force of the semiconductor sensor chip only by bonding the light shielding cover. According to a third aspect of the present invention, in the first or second aspect of the present invention, since the resin is filled in the light shielding member, the bonding wire can be prevented from being exposed to the outside air, so that the corrosion of the bonding wire can be prevented. Furthermore, deformation and disconnection of the bonding wire when an impact such as vibration is applied can be prevented, and reliability can be improved.

According to a fourth aspect of the present invention, there is provided a semiconductor sensor chip in which a piezoresistor is formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate, a substrate on which the semiconductor sensor chip is mounted, and a semiconductor sensor chip. A bonding wire for connecting the electrode and the electrode of the substrate, and a frame attached to the substrate so as to cover at least the semiconductor sensor chip and the bonding wire, wherein the inside of the frame is filled with resin. Because it can prevent the bonding wire from touching the outside air,
Corrosion of the bonding wire can be prevented, and deformation and disconnection of the bonding wire when an impact such as vibration is applied can be prevented, and reliability can be improved.

According to a fifth aspect of the present invention, there is provided a semiconductor sensor chip in which a piezoresistor is formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate, and an amplifying IC for amplifying an output of the semiconductor sensor chip. And a case in which a pressure inlet is formed at an appropriate position and at least the semiconductor sensor chip and the substrate are provided, and a lid member that is adhered to the substrate and seals the amplification IC is provided. It is characterized by the fact that the moisture resistance of the amplification IC is improved, and the amplification IC due to changes in the ambient environment temperature and humidity.
The characteristic fluctuation of C can be reduced, and the reliability can be improved.

According to a sixth aspect of the present invention, as compared with the fifth aspect of the present invention, the lid member is constituted by a frame-shaped projection projecting from the inner peripheral surface of the case. The number of parts can be reduced, and assembling becomes easy.
According to a seventh aspect of the present invention, in the invention of the sixth aspect, a secondary sealing hole is formed in the case, which is communicated with a space surrounded by the lid member and the substrate, and is sealed after the lid member and the substrate are bonded. Therefore, a one-liquid type adhesive can be used as the bonding adhesive, and the secondary sealing after bonding the lid member and the substrate can be easily performed.

The invention of claim 8 is the invention of claim 5 or claim 6.
According to the invention, since the resin is filled in the lid member, the moisture resistance of the amplifier IC is further improved, and the characteristic fluctuation of the amplifier IC due to a change in ambient temperature or humidity can be reduced. Can be enhanced. Claim 9
According to the invention of claim 8, in the invention according to claim 8, since the guide groove for controlling the direction in which the resin protrudes when bonded to the substrate is formed, the direction in which the resin protrudes due to overfilling of the resin is controlled. As a result, it is possible to prevent resin from flowing into the pressure introduction hole, the air introduction hole, and the like provided in the case, and to improve reliability.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) The basic configuration of a semiconductor pressure sensor of this embodiment is substantially the same as the conventional configuration shown in FIG. 24. As shown in FIG. 1 and FIG. It is characterized in that a box-shaped light shielding cover 40 is provided. Here, the light-shielding lid 40 is attached to the ceramic substrate 10 so as to cover the semiconductor sensor chip 1, the bonding wires W made of fine aluminum wires, and the electrodes 13 (bonding pad portions) formed on the ceramic substrate 10. Note that the same components as those in the conventional configuration are denoted by the same reference numerals, description thereof will be omitted, and only different points will be described.

The light shielding cover 40 is a molded product, and is adhered to the ceramic substrate 10 by an adhesive or the like. In the light-shielding lid 40, ventilation holes 41 are formed at appropriate positions so that the inside and outside of the light-shielding lid 40 have the same atmospheric pressure in a state of being adhered to the ceramic substrate 10. In addition, the ventilation hole 41
Needs to be provided at a position where external light hardly hits the semiconductor sensor chip 1. The light-shielding lid 40 is not limited to a molded product, and may be any as long as it can shield light.

By the way, a piezoresistor constituting the resistors Ra, Rb, Rc, Rd of the bridge circuit as shown in FIG. 3 is formed on the pressure receiving diaphragm of the semiconductor sensor chip 1, and the thick film resistor R is formed on the ceramic substrate 10. ₁ and R ₂ are formed, and the output of the entire sensor including the output amplifier circuit is adjusted to a predetermined range or a target value by adjusting the resistance values of the thick film resistors R ₁ and R ₂ by trimming as in the conventional case. I'm going to drive.

Now, let us consider a case where the output of the output amplifier circuit when the pressure is not applied to the pressure receiving diaphragm through the pressure introducing hole 24 of the body 20 is set to a constant value. The voltage (differential output) between the output terminals Vout ₁ and Vout ₂ of the bridge circuit in FIG. 3 often does not become zero due to variation in resistance even when no pressure is applied to the semiconductor sensor chip 1. and laser trimming at least one of the thick film resistor R ₁ and the thick film resistor R ₂ while monitoring the amplified output of the sensor.

In this embodiment, since the semiconductor sensor chip 1 is covered with the light shielding cover 40, it is possible to prevent photoelectromotive force from being generated in the semiconductor sensor chip 1 and to use a position used for image recognition of the trimming device. The trimming can be performed with high accuracy without being affected by the illumination for alignment, and the sensitivity of the sensor can be improved. Therefore, the reliability of the sensor can be improved. In addition, since the number of times of turning on and off the illumination for positioning of the trimming device is reduced, the life of the illumination for alignment is prolonged, and as a result, manufacturing costs including maintenance costs of the manufacturing apparatus can be reduced.

(Embodiment 2) The basic configuration of a semiconductor pressure sensor of this embodiment is substantially the same as that of Embodiment 1 shown in FIGS. 1 to 3, and as shown in FIGS. On the inside, a protective agent 46 (for example, a resin such as silicon gel) having electrical insulation and excellent heat resistance, water resistance, vibration resistance, etc.
The feature is that it is filled with. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The protective agent 46 may be injected through the vent 41 after the light-shielding lid 40 is bonded to the ceramic substrate 10. In the present embodiment, since the bonding wire W made of a thin aluminum wire does not come into direct contact with the outside air, even when the bonding wire W is used in a high-temperature, high-humidity environment, corrosion of the bonding wire W can be prevented, and the reliability of the sensor is improved. . Further, since the silicone gel has high flexibility, it also plays a role of a shock absorbing agent and improves reliability against shocks due to vibrations and drops.

(Embodiment 3) The basic configuration of a semiconductor pressure sensor according to this embodiment is substantially the same as the conventional configuration shown in FIGS. 24 and 25, and as shown in FIGS. A frame 47 surrounding the side surface and the bonding wire W is bonded to the ceramic substrate 10 with an adhesive, and a protective agent 46 ′ such as silicon gel is provided inside the frame 47.
The feature is that it is filled with. The same components as those of the conventional configuration are denoted by the same reference numerals, and description thereof will be omitted.

In the present embodiment, similarly to the second embodiment, the bonding wire W made of a thin aluminum wire does not come into direct contact with the outside air. Therefore, even when the bonding wire W is used in a high-temperature and high-humidity environment, the bonding wire W is not corroded. Can be prevented, and the reliability of the sensor is improved. Further, since the silicone gel has high flexibility, it also plays a role of a shock absorbing agent and improves reliability against shocks due to vibrations and drops.

(Embodiment 4) The basic configuration of a semiconductor pressure sensor of this embodiment is substantially the same as the conventional configuration shown in FIGS. 27 and 28, and is formed of an airtight material as shown in FIG. It is characterized in that a box-shaped dehumidifying lid 50 having an open rear surface is attached to the ceramic substrate 10 so as to cover the IC 30 for amplification. The other configuration is the same as the conventional configuration, so that illustration and description are omitted.

The dehumidifying lid 50 is bonded to the ceramic substrate 10 with an adhesive such as an epoxy resin or a silicon resin. Further, the dehumidifying lid 50 may be formed of a molded product or a ceramic, or the like, as long as it can maintain a desired airtightness in a state of being adhered to the ceramic substrate 10. Also,
A through hole 12 is formed in the ceramic substrate 10 in correspondence with the mounting position of the amplification IC 30, and serves as an air hole when a one-liquid type adhesive is used. The through hole 12 is sealed with an adhesive such as epoxy after bonding the dehumidifying lid 50 to the ceramic substrate 10. The ceramic substrate 10 has a through hole 1
Instead of providing 2, the dehumidifying lid 50 may be provided with a ventilation hole.

In this embodiment, however, the amplification IC 3
The moisture resistance of 0 is remarkably improved, the offset drift is reduced to about several μV, and the sensor drift is also several mV, so that there is no problem in use. (Embodiment 5) The basic configuration of a semiconductor pressure sensor of this embodiment is substantially the same as the conventional configuration shown in FIGS.
As shown in FIG. 9, a feature is that a frame-shaped partition wall 51 protruding from the bottom surface of the body 20 and an IC storage chamber 52 formed by the bottom surface of the body 20 constitute the dehumidifying lid 50 in the fourth embodiment. In addition, the number of parts can be reduced as compared with the fourth embodiment, and the assembly is simplified.

In the present embodiment, as shown in FIG. 10, the ceramic substrate 10 on which the amplifying IC 30, the semiconductor sensor chip 1, and the like are mounted, as shown in FIG.
Is fixed via an adhesive 33 applied to the upper end surface of the partition wall 51, the upper end surface of the pressure introducing pipe 21a, and an appropriate position of the body 20. That is, the ceramic substrate 10 is
At the same time as fixing to 0, the upper end surface of the partition wall 51 is adhered to the ceramic substrate 10.

However, in this embodiment, similarly to the fourth embodiment, the moisture resistance of the amplifying IC is dramatically improved, the offset drift is reduced to about several μV, and the sensor drift is also several mV. And there is no problem in use. (Embodiment 6) The basic configuration of the semiconductor pressure sensor of this embodiment is substantially the same as that of Embodiment 5, and the through hole 12 as the ventilation hole described in Embodiment 4 is replaced with the ceramic substrate 1.
0, as shown in FIG.
Vent hole 29 communicating from outside to the inside of IC storage room 52
The feature is that it is perforated. Here, the ventilation holes 29 are secondarily sealed after the ceramic substrate 10 is bonded to the body 10.

In this embodiment, as in the case of the fourth embodiment, the moisture resistance of the IC is dramatically improved, the offset drift is reduced to about several μV, and the sensor drift is also several mV. Absolutely no problem. In the present embodiment, since the step of forming the through-holes 12 in the ceramic substrate 10 can be eliminated, the manufacturing cost can be reduced. Further, as compared with the case where the through hole 12 is provided in the ceramic substrate 10 as in the fifth embodiment, the secondary sealing is facilitated, and the step of forming the through hole 12 can be eliminated, thereby reducing the manufacturing cost. You can also.

(Embodiment 7) The basic configuration of the semiconductor pressure sensor of this embodiment is substantially the same as the conventional configuration shown in FIGS. 27 and 28, and as shown in FIG.
This embodiment is characterized in that the amplification IC 30 mounted on the IC chip 0 is sealed with the resin 71. In this embodiment, similarly to the fourth embodiment, the moisture resistance of the amplification IC 30 is dramatically improved, and the offset drift is reduced. Is reduced to about several μV, and the sensor drift is also several mV, so that there is no problem in use.
In this embodiment, the through holes 1 are formed in the ceramic substrate 10.
Since the step of forming 2 can be eliminated, the manufacturing cost can be reduced.

The package of the amplification IC 30 is a normal plastic package (for example, a so-called SOP).
, SSOP, etc.), and the sealing resin is an epoxy resin or a urethane resin. (Embodiment 8) The basic configuration of the semiconductor pressure sensor of the present embodiment is substantially the same as the conventional configuration shown in FIGS. 27 and 28, and as shown in FIG.
2 is adhered to the ceramic substrate 10, and the portion surrounded by the frame 72 is filled with the resin 71 'to seal the amplification IC 30. Thus, the moisture resistance of the amplification IC 30 can be improved. Here, the frame body 72 may be formed of a molded product, ceramic, or the like, but may be formed by applying a resin having high viscosity with a dispenser.

In this embodiment, as in the case of the fourth embodiment, the humidity resistance of the IC is dramatically improved, the offset drift is reduced to about several μV, and the sensor drift is also several mV. Absolutely no problem. By the way, in this embodiment, the frame 72 can prevent the resin 71 ′ from being unnecessarily spread, and can eliminate the adverse effect of the sealing resin 71 ′ on other parts.

(Embodiment 9) The basic configuration of a semiconductor pressure sensor of this embodiment is substantially the same as the conventional configuration shown in FIGS. 27 and 28, and as shown in FIG. It is characterized in that the amplification IC 30 mounted on the ceramic substrate 10 is covered by the body 50 and the resin 71 ″ is filled inside the lid body 50.

In this embodiment, as in the case of the fourth embodiment, the moisture resistance of the IC is remarkably improved, the offset drift is reduced to about several μV, and the sensor drift is reduced to several mV. Absolutely no problem. The lid 50 is made of a resin 71 ″ as shown in FIG.
Is filled in an appropriate amount, and then bonded so as to cover the amplification IC 30 mounted on the ceramic substrate 10 as shown in FIG.

(Embodiment 10) The basic configuration of a semiconductor pressure sensor of this embodiment is substantially the same as the conventional configuration shown in FIGS. 27 and 28. As shown in FIG. An IC accommodating chamber formed by a frame-shaped partition wall 51 and a bottom surface is provided, and a resin 77 is sealed in the IC accommodating chamber. The lid 50 according to the ninth embodiment is integrally formed with the body 20. Equivalent to something.

That is, in the present embodiment, the ceramic substrate 10 on which the amplifying IC 30 and the semiconductor sensor chip 1 are mounted as shown in FIG.
The body 20 in which the C storage chamber is filled with an appropriate amount of the sealing resin and the adhesive 33 is applied to a predetermined position (the upper end surface of the pressure introducing pipe 21a or a part of the step formed with the peripheral wall of the body 20). Adhesively fixed.

Thus, in the present embodiment, the number of components can be reduced as compared with the ninth embodiment, and the assembly is simplified. (Embodiment 11) By the way, in the semiconductor pressure sensor according to the ninth embodiment, when the cover 50 is covered with the resin 71 ″ after the cover 50 is placed on the amplification IC 30, the resin 71 ″ is used.
There is a possibility that the pressure-introducing hole 11 and the air-introducing hole 26 formed in the body 20 may protrude from the lid 50 and be closed.

In the present embodiment, as shown in FIGS. 20 and 21, a cover 50 is provided to solve this kind of problem.
It is characterized in that a notch 50a (guide groove) for controlling the direction in which the resin 71 "protrudes is formed in a portion where the resin 71" may protrude. That is, in the present embodiment, the lid 5
0, the pressure introduction hole 11 and the air introduction hole 26
Notches 50a are formed on two surfaces that are not opposed to the portion where the is formed. Thus, in this embodiment,
Since most of the resin 71 ″ that protrudes from the lid 50 protrudes from the notch 50 a, it is possible to prevent the pressure introduction hole 11 and the air introduction hole 26 from being blocked by the resin 71 ″.

(Embodiment 12) Embodiment 10
When the ceramic substrate 10 is fixed to the body 20 after the resin accommodating chamber is filled with the resin 77 in advance, the resin 77 protrudes from the IC accommodating chamber. There was a risk of being blocked.

In this embodiment, as shown in FIG. 22, a partition wall 51 of an IC storage room is used to solve this kind of problem.
Another feature is that a notch 51a for controlling the direction in which the resin protrudes is formed in a portion where the resin may protrude. That is, in the present embodiment, the notches 5 are formed on both side surfaces of the four side surfaces of the partition wall 51 that are orthogonal to the surface near the air introduction hole 26.
1 is formed. In this embodiment, since most of the resin protrudes from the notch 51, the air introduction hole 2
6 can be prevented from flowing into the resin.

(Embodiment 13) In each of the above embodiments, one of the semiconductor sensor chip 1 and the amplifying IC 30 is provided with a configuration for improving the reliability of the sensor. May be combined,
For example, the semiconductor pressure sensor as shown in FIG. 23 may be configured by combining Embodiment 2 and Embodiment 10.
That is, in the semiconductor pressure sensor shown in FIG. 23, the semiconductor sensor chip 1, the bonding wire W, etc.
0 and sealed with a protective agent 46.
The amplifying IC 30 is covered by an IC storage chamber formed by a frame-shaped partition wall 51 integrally formed with the resin housing 77, and a resin 77 is sealed in the IC storage chamber. Therefore, in the present embodiment, both the effects obtained in the second embodiment and the effects obtained in the tenth embodiment can be obtained.

In short, in the present embodiment, since the semiconductor sensor chip 1 is shielded from light by the light shielding cover 40, the semiconductor sensor chip 1 is not irradiated with external light when trimming is performed, and stable characteristic adjustment can be performed. And the sensitivity can be increased, so that the reliability can be increased. In addition, since the trimming can be performed with high accuracy without being affected by the alignment lighting of the ceramic substrate 10, the number of times of turning on and off the alignment lighting can be reduced, and the life of the alignment lighting is prolonged. The manufacturing cost including the maintenance cost of the device can be reduced. Moreover, since the bonding wire W can be prevented from being exposed to the outside air, corrosion of the bonding wire W can be prevented, and furthermore, deformation and disconnection of the bonding wire W when an impact such as vibration is applied can be prevented. Can be enhanced. Furthermore, the moisture resistance of the amplification IC 30 is improved, and the amplification IC 30
0 characteristic fluctuation can be reduced, and reliability can be improved.

[0048]

According to a first aspect of the present invention, there is provided a semiconductor sensor chip in which a piezoresistor is formed in a pressure-receiving diaphragm formed by providing a recess in a semiconductor substrate; A substrate on which an amplifier circuit for amplifying the output is formed, a bonding wire connecting the electrode of the semiconductor sensor chip and the electrode of the ceramic substrate, and a trimming resistor formed on the substrate and adjusting the output of the amplifier circuit; Since the semiconductor sensor chip is shielded from light by the light shielding member, the semiconductor sensor chip is not irradiated with external light during trimming, stable characteristic adjustment can be performed, and sensitivity can be increased, so reliability can be improved. Can be enhanced. Also,
High-precision trimming can be performed without being affected by the substrate positioning illumination, so that the number of times the positioning illumination needs to be turned on and off can be reduced, and the life of the positioning illumination can be prolonged. There is an effect that the manufacturing cost including the above can be reduced.

According to a second aspect of the present invention, in the first aspect, the light-shielding member is a box-shaped light-shielding cover that covers at least the semiconductor sensor chip and the bonding wire, has a ventilation hole, and is open on one side. There is an effect that generation of photoelectromotive force of the semiconductor sensor chip can be suppressed only by bonding the light shielding cover. The invention of claim 3 is
In the first or second aspect of the present invention, since the resin is filled in the light shielding member, it is possible to prevent the bonding wire from being exposed to the outside air, so that the bonding wire can be prevented from being corroded, and furthermore, shock such as vibration can be prevented. It is possible to prevent deformation and disconnection of the bonding wire when added, and it is possible to improve the reliability.

According to a fourth aspect of the present invention, there is provided a semiconductor sensor chip in which a piezoresistor is formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate, a substrate on which the semiconductor sensor chip is mounted, and a semiconductor sensor chip. A bonding wire for connecting the electrode and the electrode of the substrate, and a frame attached to the substrate so as to cover at least the semiconductor sensor chip and the bonding wire, wherein the inside of the frame is filled with resin. Because it can prevent the bonding wire from touching the outside air,
Corrosion of the bonding wire can be prevented, and furthermore, deformation and disconnection of the bonding wire when an impact such as vibration is applied can be prevented, so that reliability can be improved.

According to a fifth aspect of the present invention, a semiconductor sensor chip having a piezoresistor formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate, and an amplifying IC for amplifying an output of the semiconductor sensor chip are mounted. And a case in which a pressure inlet is formed at an appropriate position and at least the semiconductor sensor chip and the substrate are provided, and a lid member that is adhered to the substrate and seals the amplification IC is provided. It is characterized by the fact that the moisture resistance of the amplification IC is improved, and the amplification IC due to changes in the ambient environment temperature and humidity.
There is an effect that the characteristic fluctuation of C can be reduced and the reliability can be improved.

According to a sixth aspect of the present invention, as compared with the fifth aspect of the present invention, the lid member is constituted by a frame-shaped projection projecting from the inner peripheral surface of the case. This has the effect of reducing the number of parts and facilitating assembly. According to a seventh aspect of the present invention, in the invention of the sixth aspect, a secondary sealing hole is formed in the case, which is communicated with a space surrounded by the lid member and the substrate, and is sealed after the lid member and the substrate are bonded. Therefore, a one-liquid type adhesive can be used as the bonding adhesive, and the secondary sealing after bonding the lid member and the substrate can be easily performed.

The invention of claim 8 is the invention of claim 5 or claim 6.
According to the invention, since the resin is filled in the lid member, the moisture resistance of the amplifier IC is further improved, and the characteristic fluctuation of the amplifier IC due to a change in ambient temperature or humidity can be reduced. There is an effect that the property can be improved. The invention according to claim 9 is the invention according to claim 8,
Since the cover member has a guide groove for controlling the direction in which the resin protrudes when it is bonded to the substrate, the direction in which the resin protrudes due to overfilling of the resin can be controlled. It is possible to prevent the resin from flowing into the air or the air introduction hole, and to improve the reliability.

[Brief description of the drawings]

FIGS. 1A and 1B show a state where a cover of a semiconductor pressure sensor according to a first embodiment is removed, wherein FIG. 1A is a plan view and FIG.

FIG. 2 shows a main part of the above, (a) is a plan view,
(B) is a sectional view.

FIG. 3 is a main part circuit diagram in the same.

4A and 4B show a state where a cover of a semiconductor pressure sensor according to a second embodiment is removed, wherein FIG. 4A is a plan view and FIG.

FIG. 5 shows a main part of the above, (a) is a plan view,
(B) is a sectional view.

6A and 6B show a state in which a cover of the semiconductor pressure sensor according to the third embodiment is removed, wherein FIG. 6A is a plan view and FIG. 6B is a cross-sectional view.

FIGS. 7A and 7B show essential parts of the above, FIG.
(B) is a sectional view.

8A and 8B show a main part in a fourth embodiment, where FIG. 8A is a plan view and FIG. 8B is a cross-sectional view.

9A and 9B show a fifth embodiment, in which FIG. 9A is a plan view with a cover removed, and FIG. 9B is a cross-sectional view.

10A and 10B show essential parts of the above, wherein FIG. 10A is a schematic external perspective view seen from the rear side, and FIG. 10B is a schematic external perspective view seen from the front side.

FIG. 11 is an explanatory diagram of how the ceramic substrate is incorporated into a body in the above.

12A and 12B show a sixth embodiment, in which FIG. 12A is a plan view with a cover removed, and FIG. 12B is a cross-sectional view.

13A and 13B show a main part in a seventh embodiment, where FIG. 13A is a plan view and FIG. 13B is a cross-sectional view.

14A and 14B show a main part in an eighth embodiment, where FIG. 14A is a plan view and FIG. 14B is a cross-sectional view.

15A and 15B show a main part in a ninth embodiment, where FIG. 15A is a plan view and FIG. 15B is a cross-sectional view.

FIG. 16 is an explanatory diagram of an assembling step of the embodiment.

FIGS. 17A and 17B show the tenth embodiment, wherein FIG. 17A is a plan view with a cover removed, and FIG.

18 (a) and 18 (b) are schematic perspective views of the essential parts of the above, as viewed from the rear side, and FIG. 18 (b) is a schematic perspective view of the external parts viewed from the front side.

FIG. 19 is an explanatory diagram of how to incorporate the ceramic substrate into the body in the above.

FIGS. 20A and 20B show a main part of the eleventh embodiment, wherein FIG. 20A is a plan view and FIG.

FIG. 21 is an explanatory diagram of how to incorporate the ceramic substrate into the body in the above.

FIG. 22 is an explanatory diagram of a method of incorporating a ceramic substrate into a body according to a twelfth embodiment.

23 shows the thirteenth embodiment, (a) is a plan view with a cover removed, and (b) is a cross-sectional view. FIG.

24A and 24B show a conventional example, in which FIG. 24A is a plan view with a cover removed, and FIG. 24B is a cross-sectional view with the cover removed.

25 (a) is a plan view, and FIG.
Is a front view.

FIG. 26 is an external perspective view of the body in the above.

27A and 27B show another conventional example, in which FIG. 27A is a plan view with a cover removed, and FIG. 27B is a cross-sectional view.

28 (a) is a plan view, and FIG.
Is a front view.

[Explanation of symbols]

1 sensor chip 10 ceramic substrate 20 body 24 the pressure introducing hole 30 for amplifying IC 40 shielding cover 41 vent W bonding wire R _1, R ₂ film resistor

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[Procedure amendment]

[Submission date] July 7, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007] In this type of semiconductor pressure sensor, variations in the magnitude (sensitivity) of the output with respect to the pressure of the sensor itself,
Since the change in the characteristics with respect to the ambient temperature is large, it is often difficult to control the characteristics to the required accuracy. For this reason, the output of the sensor is measured once after assembly, and the resistance values of the thick film resistors R ₁ and R ₂ for trimming on the ceramic substrate 10 are calculated (hereinafter, referred to as predetermined values). By trimming with a laser, the characteristics are driven to a required range or a target value. There are roughly two types of trimming methods. One is a method of obtaining the resistance value of the thick film resistor and trimming the thick film resistors R ₁ and R ₂ so as to reach the predetermined value, and the other is an output amplification. This is a function trimming in which the thick film resistors R ₁ and R ₂ are trimmed while monitoring the output voltage of the circuit to drive the output voltage to a predetermined range or a predetermined value.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

[0014]

In order to achieve the above object, according to the present invention, there is provided a semiconductor sensor chip in which a piezoresistor is formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate; A substrate on which the semiconductor sensor chip is mounted and on which an amplifier circuit for amplifying the output of the semiconductor sensor chip is formed; bonding wires connecting the electrodes of the semiconductor sensor chip and the electrodes of the ceramic substrate; A trimming resistor for adjusting the output, wherein the semiconductor sensor chip is shielded from light by a light-blocking member, so that the semiconductor sensor chip is not irradiated with external light when trimming is performed. Therefore, stable characteristic adjustment is possible ,
Since the accuracy of the adjustment can be improved , the reliability can be improved. In addition, since trimming can be performed with high precision without being affected by the illumination for positioning the substrate, the number of times of turning on and off the illumination for alignment can be reduced, and the life of the illumination for alignment is prolonged. Manufacturing costs including maintenance costs can be reduced.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

According to a sixth aspect of the present invention, as compared with the fifth aspect of the present invention, the lid member is constituted by a frame-shaped protrusion projecting from the inner peripheral surface of the case. The number of parts can be reduced, and assembling becomes easy.
According to a seventh aspect of the present invention, in the invention of the sixth aspect, a secondary sealing hole is formed in the case, which is communicated with a space surrounded by the lid member and the substrate, and is sealed after the lid member and the substrate are bonded. Therefore, a one-liquid type adhesive can be used as the bonding adhesive, and the secondary sealing after bonding the lid member and the substrate can be easily performed.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

In this embodiment, since the semiconductor sensor chip 1 is covered with the light shielding cover 40, it is possible to prevent photoelectromotive force from being generated in the semiconductor sensor chip 1 and to use a position used for image recognition of the trimming device. It can be trimmed with high accuracy without being affected by the lighting for alignment, and can be adjusted
Therefore , the reliability of the sensor can be increased. In addition, since the number of times of turning on and off the illumination for positioning of the trimming device is reduced, the life of the illumination for alignment is prolonged, and as a result, manufacturing costs including maintenance costs of the manufacturing apparatus can be reduced.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0048

[Correction method] Change

[Correction contents]

[0048]

According to a first aspect of the present invention, there is provided a semiconductor sensor chip in which a piezoresistor is formed in a pressure-receiving diaphragm formed by providing a recess in a semiconductor substrate; A substrate on which an amplifier circuit for amplifying the output is formed, a bonding wire connecting the electrode of the semiconductor sensor chip and the electrode of the ceramic substrate, and a trimming resistor formed on the substrate and adjusting the output of the amplifier circuit; Since the semiconductor sensor chip is shielded from light by the light shielding member, the semiconductor sensor chip is not irradiated with external light during trimming, stable characteristic adjustment can be performed , and the adjustment accuracy can be improved.
Because it is Mel that, it is possible to improve the reliability.
In addition, since trimming can be performed with high precision without being affected by the illumination for positioning the substrate, the number of times of turning on and off the illumination for alignment can be reduced, and the life of the illumination for alignment is prolonged. There is an effect that manufacturing costs including maintenance costs can be reduced.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0052

[Correction method] Change

[Correction contents]

According to a sixth aspect of the present invention, as compared with the fifth aspect of the present invention, the lid member is constituted by a frame-shaped projection projecting from the inner peripheral surface of the case. This has the effect of reducing the number of parts and facilitating assembly. According to a seventh aspect of the present invention, in the invention of the sixth aspect, a secondary sealing hole is formed in the case, which is communicated with a space surrounded by the lid member and the substrate, and is sealed after the lid member and the substrate are bonded. Therefore, a one-liquid type adhesive can be used as the bonding adhesive, and the secondary sealing after bonding the lid member and the substrate can be easily performed.

Claims (9)

[Claims] A semiconductor sensor chip in which a piezoresistor is formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate, and an amplifier circuit in which the semiconductor sensor chip is mounted and which amplifies the output of the semiconductor sensor chip. A substrate formed, a bonding wire connecting the electrodes of the semiconductor sensor chip and the electrodes of the ceramic substrate, and a trimming resistor formed on the substrate and adjusting the output of the amplifier circuit. A semiconductor pressure sensor characterized by being shielded from light. 2. The semiconductor pressure sensor according to claim 1, wherein the light-shielding member is a box-shaped light-shielding lid that covers at least the semiconductor sensor chip and the bonding wire, has a ventilation hole, and is open on one side. 3. The semiconductor pressure sensor according to claim 1, wherein the light shielding member is filled with a resin. 4. A semiconductor sensor chip in which a piezoresistor is formed in a pressure-receiving diaphragm formed by providing a recess in a semiconductor substrate, a substrate on which the semiconductor sensor chip is mounted, electrodes of the semiconductor sensor chip, and electrodes of the substrate. And a frame attached to the substrate so as to cover at least the semiconductor sensor chip and the bonding wire, wherein the inside of the frame is filled with a resin. Sensor. 5. A semiconductor sensor chip having a piezoresistor formed in a pressure receiving diaphragm formed by providing a recess in a semiconductor substrate, a substrate on which an amplifying IC for amplifying an output of the semiconductor sensor chip is mounted, and A semiconductor pressure, comprising: a case in which an inlet is formed at an appropriate position and at least a semiconductor sensor chip and a substrate are provided; and a lid member adhered to the substrate and sealing the amplification IC is provided. Sensor. 6. The semiconductor pressure sensor according to claim 5, wherein the lid member is constituted by a frame-shaped projection projecting from an inner peripheral surface of the case. 7. A case in which a secondary sealing hole is formed in the case, which is communicated with a space surrounded by the lid member and the substrate and which is sealed after the lid member and the substrate are bonded. 7. The semiconductor pressure sensor according to 6. 8. The semiconductor pressure sensor according to claim 5, wherein a resin is filled in the lid member. 9. The semiconductor pressure sensor according to claim 8, wherein a guide groove for controlling a direction in which the resin protrudes when the cover member is adhered to the substrate is formed in the lid member.