JP3716165B2 - Pressure detection device package and pressure detection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pressure detection device package used in a pressure detection device for detecting pressure.
[0002]
[Prior art]
Conventionally, a capacitance type pressure detection device is known as a pressure detection device for detecting pressure. For example, as shown in a cross-sectional view in FIG. 4, the capacitance type pressure detection device is accommodated in a capacitance type pressure sensitive element 22 and a package 28 on a wiring board 21 made of a ceramic material or a resin material. And a semiconductor element 29 for operation. The pressure sensitive element 22 is made of, for example, an electrically insulating material such as a ceramic material, and has an insulating base 24 having a concave portion in which one electrode 23 for forming a capacitance is attached at the center of the upper face, and an upper face of the insulating base 24 And an insulating plate 26 which is joined in a flexible state so as to form a sealed space with the insulating base 24, and the other electrode 25 for forming a capacitance is attached to the lower surface, and each capacitance It is composed of external lead terminals 27 for electrically connecting the forming electrodes 23 and 25 to the outside, and the insulating plate 26 bends in response to external pressure, thereby forming each capacitance. The capacitance formed between the electrodes 23 and 25 changes. Then, the external pressure can be detected by performing arithmetic processing on the change in the electrostatic capacitance by the semiconductor element 29 for arithmetic operation.
[0003]
[Problems to be solved by the invention]
However, according to this conventional pressure detection device, since the pressure sensitive element 22 and the semiconductor element 29 are individually mounted on the wiring board 21, the pressure detection device becomes large and the pressure detection electrode 23 is increased. The wiring between 25 and the semiconductor element 29 becomes long, and an unnecessary electrostatic capacity is formed between the long wiring, so that the sensitivity is low.
[0004]
Therefore, the applicant of the present application previously described in Japanese Patent Application No. 2000-178618, an insulating base having a mounting portion on which a semiconductor element is mounted on one main surface, and the surface of and inside the insulating base, A plurality of wiring conductors to which each electrode is electrically connected, and a first capacitor for forming a capacitance that is attached to the central portion of the other main surface of the insulating base and is electrically connected to one of the wiring conductors. An insulating plate joined in a flexible state so as to form a sealed space between the electrode and the other main surface of the insulating base, and a central portion of the main surface; and an inner main surface of the insulating plate There has been proposed a pressure sensing device package comprising a second electrode for forming a capacitance that is deposited opposite to one electrode and is electrically connected to the other one of the wiring conductors. According to this pressure detection device package, the first electrode for forming a capacitance is provided on the other main surface of the insulating base having the mounting portion on which the semiconductor element is mounted on one main surface. Since the insulating plate having the second electrode for forming the opposing capacitance on the inner surface is joined in a flexible state so as to form a sealed space between the other main surface of the insulating base, A pressure-sensitive element is integrally formed in a package that houses a semiconductor element. As a result, the pressure detection device can be reduced in size, and the wiring for connecting the pressure detection electrode and the semiconductor element can be shortened. Unnecessary capacitance generated between the wirings can be reduced.
[0005]
However, according to the package for a pressure detection device proposed in Japanese Patent Application No. 2000-178618, the insulating plate is made of a brittle ceramic material. Therefore, when external pressure is repeatedly applied to the insulating plate, Small cracks are generated at the periphery, and this gradually progresses to the center of the insulating plate. Finally, the hermeticity of the sealed space between the insulating base and the insulating plate is lowered, so that the external pressure can be accurately adjusted. There has been a problem that it may become impossible to detect.
[0006]
The present invention has been completed in view of the above-mentioned problems, and an object of the present invention is to provide a pressure detection device that is small in size and high in sensitivity and can accurately detect external pressure over a long period of time. There is to do.
[0007]
[Means for Solving the Problems]
A package for a pressure detection device according to the present invention includes a ceramic base having a mounting portion on which a semiconductor element is mounted on one main surface, and a surface and inside of the ceramic base, and each electrode of the semiconductor element is electrically A plurality of metallized wiring conductors connected to a first metallization for forming a capacitance, which is attached to a central portion of the other main surface of the ceramic base and is electrically connected to one of the metallized wiring conductors An electrode, a ceramic plate joined in a flexible state so as to form a sealed space between the other main surface and the central portion; and the first metallized electrode on the inner main surface of the ceramic plate; A package for a pressure detection device comprising a second metallization electrode for forming a capacitance, which is deposited oppositely and electrically connected to another one of the metallized wiring conductors, the ceramic plate The reinforcing metallization layer formed by firing a metallized paste containing metal powder together with the ceramic green sheet for the ceramic plate is applied to substantially the entire outer main surface. is there.
Further, in the package for a pressure detection device of the present invention, a concave portion for accommodating the semiconductor element is formed in the central portion of the lower surface of the ceramic substrate, and the central portion of the bottom surface of the concave portion is the mounting portion. A portion of the metallized wiring conductor led out to the lower surface of the outer periphery of the ceramic base is joined to the wiring conductor of the external electric circuit board.
The pressure detection device of the present invention includes a semiconductor element, a ceramic base having a concave portion in which the semiconductor element is accommodated on one main surface, a surface of the ceramic base and the inside thereof, and each electrode of the semiconductor element includes A plurality of metallized wiring conductors that are electrically connected to each other and a central portion of the other main surface of the ceramic base, and a first capacitor for forming a capacitance that is electrically connected to one of the metallized wiring conductors. A ceramic plate joined in a flexible state so as to form a sealed space between the one metallized electrode and the other main surface with the central portion; and the first metallized on the inner main surface of the ceramic plate A second metallization electrode for forming a capacitance, which is deposited opposite to the electrode and electrically connected to the other one of the metallized wiring conductors, and the metallized wiring conductors from the side surface of the ceramic substrate One main surface of the ceramic base located on the side is led out around the opening of the recess, and the lead is joined to the wiring conductor of the external electric circuit board It is.
[0008]
According to the pressure detection device package of the present invention, the first metallization electrode for forming the capacitance is provided on the other main surface of the ceramic base having the mounting portion on which the semiconductor element is mounted on one main surface. A ceramic plate having a second metallized electrode for forming a capacitance opposite to the first metallized electrode on its inner surface is flexible so as to form a sealed space between the other main surface of the ceramic substrate. As a result, the pressure-sensitive element is integrally formed in the package that accommodates the semiconductor element. As a result, the pressure detection device can be miniaturized and wiring for connecting the pressure detection electrode and the semiconductor element can be provided. As short, unnecessary capacitance generated between these wirings can be reduced. Furthermore, since a reinforcing metallization layer is applied to substantially the entire outer main surface of the ceramic plate, cracks may occur in the outer periphery of the ceramic plate when external pressure is repeatedly applied to the ceramic plate. Is effectively prevented, and even if a crack occurs, it is effectively prevented that the crack progresses to the center of the ceramic plate.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing an example of an embodiment of a pressure detection device package according to the present invention, in which 1 is a ceramic substrate, 2 is a ceramic plate, and 3 is a semiconductor element.
[0010]
The ceramic substrate 1 is a laminated body made of a ceramic material such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, a silicon carbide sintered body, a silicon nitride sintered body, or a glass-ceramic. For example, in the case of an aluminum oxide sintered body, an appropriate organic binder, solvent, plasticizer, and dispersant are added to and mixed with ceramic raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide. Then, it is made into a mud shape and formed into a sheet shape by adopting a conventionally known doctor blade method, and then a plurality of ceramic green sheets are obtained. -A green ceramic molded body for the insulating substrate 1 is obtained by cutting, and this green ceramic is obtained. It is manufactured by firing a form at a temperature of about 1600 ° C..
[0011]
The ceramic substrate 1 has a recess 1a for accommodating the semiconductor element 3 at the center of the lower surface thereof, thereby functioning as a container for accommodating the semiconductor element 3. The central portion of the bottom surface of the recess 1a is a mounting portion 1b on which the semiconductor element 3 is mounted. The semiconductor element 3 is mounted on the mounting portion 1b and the resin sealing such as an epoxy resin is provided in the recess 1a. The semiconductor element 3 is sealed by filling the material 4. In this example, the semiconductor element 3 is sealed by filling the recess 1a with the resin sealing material 4. However, the semiconductor element 3 has a lid made of metal or ceramics on the lower surface of the ceramic base 1 to form the recess 1a. It may be sealed by bonding so as to block.
[0012]
Further, a plurality of metallized wiring conductors 5 connected to the respective electrodes of the semiconductor element 3 are led out to the mounting portion 1b, and the metalized wiring conductors 5 and the respective electrodes of the semiconductor element 3 are connected to conductive materials such as solder bumps 6 and the like. The electrodes of the semiconductor element 3 and the metallized wiring conductors 5 are electrically connected to each other through the conductive bonding member made of the semiconductor element 3 and the semiconductor element 3 is fixed to the mounting portion 1b. In this example, the electrode of the semiconductor element 3 and the metallized wiring conductor 5 are connected via the solder bumps 6. However, the electrode of the semiconductor element 3 and the metalized wiring conductor 5 are connected to other types of electric wires such as bonding wires. It may be connected by a general connection means.
[0013]
The metallized wiring conductor 5 functions as a conductive path for electrically connecting each electrode of the semiconductor element 3 to an external electric circuit and a first metallized electrode 7 and a second metallized electrode 9 to be described later, and a part thereof is a ceramic substrate. The other part is electrically connected to the first metallized electrode 7 and the second metallized electrode 9. Each electrode of the semiconductor element 3 is electrically connected to these metallized wiring conductors 5 via the conductive bonding material 6 and the semiconductor element 3 is sealed with the resin sealing material 4. The portion led out to the lower surface of the outer periphery of the ceramic substrate 1 is joined to the wiring conductor of the external electric circuit board via a conductive bonding material such as solder, so that the semiconductor element 3 accommodated therein is electrically connected to the external electric circuit. Will be.
[0014]
Such a metallized wiring conductor 5 is made of metal powder metallization such as tungsten, molybdenum, copper, and silver, and is obtained by adding and mixing an appropriate organic binder, solvent, plasticizer, dispersant, and the like to metal powder such as tungsten. The metallized paste is printed and applied in a predetermined pattern on a ceramic green sheet for the ceramic substrate 1 by employing a conventionally known screen printing method, and is fired together with a green ceramic molded body for the ceramic substrate 1 to thereby form the ceramic substrate 1. A predetermined pattern is formed inside and on the surface. In order to prevent the metallized wiring conductor 5 from being oxidized and corroded on the exposed surface of the metallized wiring conductor 5 and to improve the bonding between the metallized wiring conductor 5 and a conductive bonding material such as solder, If so, a nickel plating layer having a thickness of about 1 to 10 μm and a gold plating layer having a thickness of about 0.1 to 3 μm are sequentially deposited.
[0015]
Further, a frame-shaped protrusion 1c having a height of about 0.01 to 5 mm is provided on the outer peripheral portion of the upper surface of the ceramic substrate 1, thereby forming a recess 1d having a substantially flat bottom surface at the center of the upper surface. As will be described later, the concave portion 1d is for forming a sealed space between the concave portion 1d and the first metallized electrode 7 for forming a capacitance is attached to the bottom surface of the concave portion 1d. ing.
[0016]
The first metallized electrode 7 is for forming a capacitance for a pressure sensitive element together with a second metallized electrode 9 to be described later, and is formed in a substantially circular pattern, for example. The first metallized electrode 7 is connected to one of the metallized wiring conductors 5a, whereby the electrode of the semiconductor element 3 is connected to the metallized wiring conductor 5a via a conductive bonding material such as a solder bump 6. When connected, the electrode of the semiconductor element 3 and the first metallized electrode 7 are electrically connected.
[0017]
Such a first metallized electrode 7 is made of metal powder metallization such as tungsten, molybdenum, copper, and silver, and is obtained by adding and mixing an appropriate organic binder, solvent, plasticizer, and dispersant to metal powder such as tungsten. The metallized paste is printed and applied to a ceramic green sheet for the ceramic substrate 1 using a conventionally known screen printing method, and is fired together with a green ceramic molded body for the ceramic substrate 1 to form the bottom surface of the recess 1d of the ceramic substrate 1. A predetermined pattern is formed. Note that a nickel plating layer having a thickness of about 1 to 10 μm is normally applied to the exposed surface of the first metallized electrode 7 in order to prevent the first metallized electrode 7 from being oxidized and corroded. .
[0018]
Further, a frame-like bonding metallization layer 8 is deposited on the entire upper surface of the protrusion 1c of the ceramic substrate 1, and the bonding metallization layer 8 has a second metallization electrode 9 on the lower surface. The ceramic plate 2 is attached by bonding the second metallized electrode 9 and the bonding metallized layer 8 via a conductive bonding material such as a silver-copper brazing material.
[0019]
One metal metallization wiring conductor 5b is connected to the metallization layer 8 for bonding, whereby the electrode of the semiconductor element 3 is electrically connected to the metallized wiring conductor 5b via a conductive bonding material such as a solder bump 6. As a result, the second metallized electrode 9 connected to the bonding metallized layer 8 and the electrode of the semiconductor element 3 are electrically connected.
[0020]
The metallization layer 8 for bonding is made of metal powder metallization such as tungsten, molybdenum, copper, and silver. A conventionally known screen printing method is used to print and apply to a ceramic green sheet for the ceramic substrate 1, and this is fired together with a green ceramic molded body for the ceramic substrate 1 to form a frame shape on the upper surface of the protrusion 1 c of the ceramic substrate 1. Are formed in a predetermined pattern. In order to prevent the joining metallized layer 8 from being oxidized and corroded on the exposed surface of the joining metallized layer 8 and to strengthen the joining between the joining metallized layer 8 and the conductive joining material, If so, a nickel plating layer having a thickness of about 1 to 10 μm is applied.
[0021]
The ceramic plate 2 attached to the upper surface of the ceramic substrate 1 is made of an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, a silicon nitride sintered body, or a silicon carbide sintered body. A substantially flat plate having a thickness of 0.01 to 5 mm made of a ceramic material such as glass-ceramics, and functions as a so-called pressure detecting diaphragm that bends toward the ceramic substrate 1 in response to external pressure.
[0022]
In addition, since the mechanical strength of the ceramic plate 2 is less than 0.01 mm, the mechanical strength becomes small. Therefore, there is a high risk of being destroyed when a large external pressure is applied thereto. On the other hand, when it exceeds 5 mm, it becomes difficult to bend at a small pressure, and it becomes unsuitable as a diaphragm for pressure detection. Therefore, the thickness of the ceramic plate 2 is preferably in the range of 0.01 to 5 mm.
[0023]
If such a ceramic plate 2 is made of, for example, an aluminum oxide sintered body, a suitable organic binder, solvent, plasticizer, dispersion for ceramic raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, etc. A ceramic green sheet is obtained by adding an agent and mixing it into a mud and forming it into a sheet using the well-known doctor blade method, and then punching or cutting the ceramic green sheet appropriately. The green ceramic molded body for the ceramic plate 2 is obtained by processing, and the green ceramic molded body is manufactured by firing at a temperature of about 1600 ° C.
[0024]
Further, a second metallized electrode 9 for forming a capacitance is deposited on substantially the entire lower surface of the ceramic plate 2. The second metallized electrode 9 functions as an electrode for forming a capacitance for a pressure sensitive element together with the first metallized electrode 7 described above, and is a bonding base metal for bonding the ceramic plate 2 to the ceramic substrate 1. Acts as a layer.
[0025]
Such a second metallized electrode 9 is made of metal powder metallization such as tungsten, molybdenum, copper, and silver, and is obtained by adding and mixing an appropriate organic binder, solvent, plasticizer, and dispersant to metal powder such as tungsten. The metallized paste is printed and applied to a ceramic green sheet for the ceramic plate 2 using a conventionally well-known screen printing method, and this is fired together with a green ceramic molded body for the ceramic plate 2, thereby substantially the entire lower surface of the ceramic plate 2. In a predetermined pattern. In order to prevent the second metallized electrode 9 from being oxidatively corroded on the exposed surface of the second metallized electrode 9, and to improve the bonding between the second metallized electrode 9 and the conductive bonding material, it is usual. For example, a nickel plating layer having a thickness of about 1 to 10 μm is applied.
[0026]
The second metallized electrode 9 and the bonding metallized layer 8 are bonded to each other through a conductive bonding material such as a silver-copper brazing material, whereby the hermetic sealing is performed between the upper surface of the ceramic substrate 1 and the lower surface of the ceramic plate 2. A space is formed and the bonding metallized layer 8 and the second metallized electrode 9 are electrically connected.
[0027]
At this time, the first metallized electrode 7 and the second metallized electrode 9 are opposed to each other with a space formed between the ceramic base 1 and the ceramic plate 2 interposed therebetween. 7 and a second metallized electrode 9 and a predetermined capacitance is formed according to the distance between the first metallized electrode 7 and the second metallized electrode 9. When an external pressure is applied to the upper surface of the ceramic plate 2, the ceramic plate 2 is bent toward the ceramic base 1 in accordance with the pressure, and the interval between the first metallized electrode 7 and the second metallized electrode 9 is changed. As a result, the capacitance between the first metallized electrode 7 and the second metallized electrode 9 changes, so that it functions as a pressure-sensitive element that senses a change in external pressure as a change in capacitance. Then, the change in electrostatic capacity is transmitted to the semiconductor element 3 accommodated in the recess 1a through the metallized wiring conductors 5a and 5b, and this is processed by the semiconductor element 3 so as to know the magnitude of the external pressure. be able to.
[0028]
Thus, according to the package for a pressure detection device of the present invention, the first metallized electrode 7 for forming a capacitance is formed on the other main surface of the ceramic substrate 1 on which the semiconductor element 3 is mounted on one main surface. And a flexible state so that a sealed space is formed between the ceramic plate 2 having the second metallized electrode 9 for forming a capacitance opposed to the first metallized electrode 7 on the inner main surface and the ceramic substrate 1. Therefore, the container for housing the semiconductor element 3 and the pressure sensitive element are integrated, and as a result, the pressure detection device can be reduced in size. In addition, since the first metallized electrode 7 and the second metallized electrode 9 for forming capacitance are connected to the semiconductor element 3 via the metallized wiring conductors 5a and 5b provided on the ceramic substrate 1, the first metallized electrode 7 And the second metallized electrode 9 can be connected to the semiconductor element 3 at a short distance. As a result, an unnecessary capacitance generated between the metallized wiring conductors 5a and 5b is reduced, and the pressure detecting device is highly sensitive. Can be provided.
[0029]
In addition, when the space | interval of the 1st metallization electrode 7 and the 2nd metallization electrode 9 is less than 0.01 mm in 1 atmosphere, when a big pressure is applied to the ceramic board 2, the 1st metallization electrode 7 and the 2nd metallization electrode There is a risk that the pressure cannot be detected due to contact with 9, and on the other hand, if the thickness exceeds 5 mm, the capacitance formed between the first metallized electrode 7 and the second metallized electrode 9 is increased. It tends to be small, and the sensitivity to detect pressure tends to be low. Therefore, the distance between the first metallized electrode 7 and the second metallized electrode 9 is preferably in the range of 0.01 to 5 mm at 1 atmosphere.
[0030]
Further, a reinforcing metallized layer 10 is applied to the upper surface of the ceramic plate 2 over substantially the entire surface thereof. The reinforcing metallization layer 10 is made of metal powder metallization such as tungsten, molybdenum, copper, and silver. When external pressure is repeatedly applied to the ceramic plate 2, cracks are generated in the outer peripheral portion of the ceramic plate 2. While preventing, even if a crack occurs, it functions as a barrier for preventing the crack from progressing to the center of the ceramic plate 2. Thus, according to the package for a pressure detection device of the present invention, since the reinforcing metallized layer 10 is deposited on substantially the entire outer main surface of the ceramic plate 2, external pressure is repeatedly applied to the ceramic plate 2. Even if it is applied, it is possible to effectively prevent cracks from occurring in the outer peripheral portion of the ceramic plate 2, and even if cracks occur, the cracks may travel to the center of the ceramic plate 2. As a result, the hermeticity of the sealed space formed between the ceramic base 1 and the ceramic plate 2 is not lowered, and therefore the external pressure can be accurately detected over a long period of time. is there.
[0031]
When the thickness of the reinforcing metallized layer 10 is less than 5 μm, when external pressure is repeatedly applied to the ceramic plate 2, cracks are generated in the outer peripheral portion of the ceramic plate 2, and the cracks are generated in the ceramic plate. The risk of not being able to effectively prevent traveling to the center of 2 increases, and if it exceeds 50 μm, the reinforcement is caused by the difference in thermal expansion coefficient between the ceramic plate 2 and the reinforcing metallization layer 10. The risk of the metallization layer 10 for peeling off from the ceramic plate 2 increases. Therefore, the thickness of the reinforcing metallized layer 10 is preferably in the range of 5 to 50 μm.
[0032]
Such a reinforcing metallization layer 10 is a ceramic plate obtained by applying a conventionally known screen printing method to a metallized paste obtained by adding and mixing an appropriate organic binder, solvent, plasticizer, and dispersant to a metal powder such as tungsten. A ceramic green sheet for 2 is printed and applied and fired together with a green ceramic molded body for the ceramic plate 2 to form a predetermined pattern on substantially the entire upper surface of the ceramic plate 2. Further, in order to prevent the reinforcing metallized layer 10 from being oxidized and corroded on the exposed surface of the reinforcing metallized layer 10, a nickel plating layer having a thickness of about 1 to 10 μm and a thickness of 0.1 to 3 μm are usually used. About a gold plating layer is applied.
[0033]
Thus, according to the above-described package for the pressure detection device, the semiconductor element 3 is mounted on the mounting portion 1b, and each electrode of the semiconductor element 3 and the metallized wiring conductor 5 are electrically connected. Sealing provides a highly reliable pressure detection device that is small and highly sensitive and that can accurately detect external pressure over a long period of time.
[0034]
Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the above-described embodiment, a frame-like protrusion 1c is provided on the outer peripheral portion of the upper surface of the ceramic substrate 1, and the ceramic plate 2 is bonded onto the protrusion 1c, whereby the upper surface of the ceramic substrate 1, the ceramic plate 2, and the like. However, according to the present invention, as shown in a sectional view in FIG. 2, a frame-like protrusion 2a is provided on the outer periphery of the lower surface of the ceramic plate 2, and this is joined to the upper surface of the ceramic substrate 1. By doing so, a sealed space may be provided between the ceramic substrate 1 and the ceramic plate 2. In this case, a metallizing layer 11 for bonding may be provided on the lower surface of the protruding portion 2a, and the metallizing layer 11 for bonding may be bonded to the metallizing layer 8 for bonding via a conductive bonding material such as silver-copper solder. The joining metallized layer 11 and the second metallized electrode 9 may be electrically connected by providing a connecting metallized conductor 12 for connecting them to the ceramic plate 2.
[0035]
Further, according to the present invention, as shown in a cross-sectional view in FIG. 3, a metal frame 13 made of, for example, iron-nickel-cobalt alloy or iron-nickel alloy is provided on the outer peripheral portion of the upper surface of the ceramic substrate 1. The ceramic plate 2 is bonded to the metal frame 13 via a conductive bonding material such as silver-copper brazing, and the ceramic substrate 1 and the ceramic plate 2 are bonded. A sealed space may be provided.
[0036]
【The invention's effect】
As described above, according to the pressure detection device package of the present invention, the first main surface for forming a capacitance is formed on the other main surface of the ceramic substrate having the mounting portion on which the semiconductor element is mounted on one main surface. A ceramic plate having a metallized electrode and a second metallized electrode for forming a capacitance opposite to the first metallized electrode on the inner surface is formed to form a sealed space between the other main surface of the ceramic substrate. Thus, since the pressure-sensitive element is integrated with the package that accommodates the semiconductor element, the pressure detection device can be downsized. In addition, since the first metallization electrode and the second metallization electrode for forming the capacitance are connected to the semiconductor element through the metallization wiring conductor provided on the insulating base, the first metallization electrode and the second metallization electrode are connected at a short distance. As a result, it is possible to provide a highly sensitive pressure detecting device with a small unnecessary capacitance generated between these metallized wiring conductors. Furthermore, since a reinforcing metallization layer is applied to substantially the entire outer main surface of the ceramic plate, even when external pressure is repeatedly applied to the ceramic plate, cracks are generated in the outer peripheral portion of the ceramic plate. It is possible to effectively prevent the occurrence of cracks, and even if cracks occur, the cracks are effectively prevented from proceeding to the center of the ceramic plate, and as a result, between the ceramic substrate and the ceramic plate. The hermeticity of the formed sealed space is not lowered, so that the external pressure can be accurately detected over a long period of time.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of an embodiment of a package for a pressure detection device of the present invention.
FIG. 2 is a cross-sectional view showing another example of the embodiment of the package for a pressure detection device of the present invention.
FIG. 3 is a cross-sectional view showing still another example of the embodiment of the pressure detecting device package of the present invention.
FIG. 4 is a cross-sectional view showing a conventional pressure detection device.
[Explanation of symbols]
1 ... Ceramic substrate
2. Ceramic plate
3. Semiconductor device
5, 5a, 5b ... Metallized wiring conductor
7. First metallized electrode
9 ... Second metallized electrode
10 ・ ・ ・ ・ ・ Metalizing layer for reinforcement

Claims (3)

A ceramic base having a mounting portion on which a semiconductor element is mounted on one main surface; and a plurality of metallized wiring conductors disposed on and in the surface of the ceramic base and electrically connected to the electrodes of the semiconductor element; A first metallization electrode for forming a capacitance that is attached to the center of the other main surface of the ceramic substrate and is electrically connected to one of the metallized wiring conductors; A ceramic plate joined in a flexible state so as to form a sealed space with the central portion; and an inner main surface of the ceramic plate is attached to face the first metallized electrode; A package for a pressure detecting device comprising a second metallization electrode for forming a capacitance electrically connected to the other one of the conductors, wherein the ceramic plate is disposed on substantially the entire outer main surface thereof . Metal powder Metallizing paste the package pressure detecting apparatus characterized by reinforcing metallized layer formed by firing with the ceramic green sheet is adhered for the ceramic plate including. A recess for accommodating the semiconductor element is formed at the center of the lower surface of the ceramic substrate, and the center of the bottom surface of the recess is used as the mounting portion, and the outer peripheral lower surface of the ceramic substrate of the metallized wiring conductor 2. The package for a pressure detecting device according to claim 1, wherein the derived portion is joined to the wiring conductor of the external electric circuit board. A semiconductor element, a ceramic base having a recess in which the semiconductor element is accommodated on one main surface, and a plurality of electrodes disposed on and inside the ceramic base and electrically connected to each electrode of the semiconductor element A metallized wiring conductor; a first metallized electrode for forming a capacitance that is attached to a central portion of the other main surface of the ceramic base and electrically connected to one of the metallized wiring conductors; A ceramic plate joined in a flexible state so as to form a sealed space between the central portion and the central portion, and an inner main surface of the ceramic plate is attached to face the first metallized electrode. A second metallization electrode for forming a capacitance electrically connected to the other one of the metallized wiring conductors, wherein the metallized wiring conductor is located inward from the side surface of the ceramic substrate. In one main surface of the click substrate, while being guided to the periphery of the opening of the recess, conductor output unit pressure detecting device is characterized in that so as to bond to the wiring conductor of the external electric circuit board.

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