JP2003042876A - Package for pressure detecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure detecting apparatus capable of accurately detecting external pressure over a long period. SOLUTION: This package for the pressure detecting apparatus is formed of an insulating substrate 1 and an insulating plate 2. The insulating substrate 1 comprises a mounting part 1b in which a semiconductor element 3 is mounted to one main surface, a first electrode 7 for forming electrostatic capacitance in the other main surface, a first electrode 7 for forming electrostatic capacitance in the other main surface, and a first metallized layer 8 for joining surrounding the first electrode 7. The insulating plate 2 comprises both a second electrode 9 for forming electrostatic capacitance in one main surface opposite to the first electrode 7 and a second metallized layer 10 for joining electrically connected to the second electrode 9 and brazed to the first metallized layer 8 for joining and is in a flexible state joined to the insulating substrate 1 in such a way as to form a sealed space in-between to the other main surface of the insulating substrate 1. In the insulating plate 2, a frame shaped protrusion part 2a is formed in the outer circumferential part of the one main surface of the insulating plate 2, the second metallized layer 10 for joining is pasted and formed close to the outer circumference of the protrusion part 2a, and an insulating layer 12 in contact with the insulating substrate 1 is provided for an inner circumferential part of the protrusion part 2a.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure detecting device package used for a pressure detecting device for detecting pressure. 2. Description of the Related Art Conventionally, a capacitance type pressure detecting device has been known as a pressure detecting device for detecting pressure. As shown in a sectional view of FIG. 2, for example, a capacitance type pressure sensing device 22 and a package 28 are mounted on a wiring board 21 made of a ceramic material or a resin material.
And a semiconductor element 29 for arithmetic operation housed in the computer. The pressure-sensitive element 22 is made of, for example, an electrically insulating material such as a ceramic material.
An insulating substrate 24 having a concave portion to which
An insulating plate 26, which is joined in a flexible state so as to form a closed space between the insulating base 24 and the upper surface of the insulating substrate 24, and the other electrode 25 for forming a capacitance is adhered to the lower surface, And external lead terminals 27 for electrically connecting each of the capacitance forming electrodes 23 and 25 to the outside. Each of the static electricity generating plates 23 and 25 is formed by bending the insulating plate 26 in response to external pressure. The capacitance formed between the capacitance forming electrodes 23 and 25 changes.
An external pressure can be detected by subjecting this change in capacitance to arithmetic processing by the semiconductor element 29 for arithmetic operation. [0003] However, according to this conventional pressure detecting device, the pressure-sensitive element 22 and the semiconductor element 29 are not provided.
Are individually mounted on the wiring board 21, which increases the size of the pressure detection device and the pressure detection electrode.
The wiring between 23 and 25 and the semiconductor element 29 becomes longer,
There is a problem that the sensitivity is low because an unnecessary capacitance is formed between the long wires. Accordingly, the applicant of the present application has previously filed Japanese Patent Application No. 2000-178.
618, an insulating base having a mounting portion on which a semiconductor element is mounted on one main surface; and a plurality of insulating bases disposed on and inside the insulating base, each electrode of the semiconductor element being electrically connected. A wiring conductor, a first electrode for forming a capacitance, which is attached to a 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 with the central portion of the main surface, and an inner main surface of the insulating plate is attached to the first main surface so as to face the first electrode. Thus, a pressure detection device package including a second electrode for forming a capacitance electrically connected to another one of the wiring conductors has been proposed. According to this pressure detecting device package, a first electrode for forming a capacitance is provided on the other main surface of the insulating base having a mounting portion on which a semiconductor element is mounted on one main surface, and the first electrode is provided on the first electrode. Since the insulating plate having the opposing second electrode for capacitance formation on the inner surface thereof was joined in a flexible state so as to form a sealed space between the other main surface of the insulating base, The pressure-sensitive element is formed integrally with the package containing the semiconductor element. As a result, the pressure detection device can be made small and the wiring connecting the electrode for pressure detection and the semiconductor element is shortened. Unnecessary capacitance generated between the wirings can be reduced. In the package for a pressure detecting device proposed in Japanese Patent Application No. 2000-178618, for example, a frame made of ceramics or metal is provided on the outer peripheral portion of the other main surface of the insulating base so as to surround the first electrode. The insulating plate was joined to the insulating base by brazing the outer periphery of the second electrode on the frame via a brazing material such as silver-copper brazing material. However, according to the pressure sensing device package proposed in Japanese Patent Application No. 2000-178618, the brazing material made of silver-copper brazing for joining the insulating base and the insulating plate is liable to undergo plastic deformation due to large stress. When a large external pressure is applied to the insulating plate for a long period of time, the stress generated by the bending of the insulating plate greatly acts on the inner peripheral edge of the brazing material joining the insulating base and the insulating plate. Plastic deformation occurs, and as a result, even if the application of pressure is released, the insulating plate does not completely return to its original position, making it impossible to accurately detect external pressure. Had. 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 detecting device capable of accurately detecting external pressure over a long period of time. A package for a pressure detecting device according to the present invention has a plurality of wiring conductors inside and on the surface, and has a mounting portion on one main surface on which a semiconductor element is mounted, and a mounting portion on the other side. A first electrode for forming a capacitance electrically connected to one of the wiring conductors on the main surface and a frame-shaped first electrode surrounding the first electrode and electrically connected to the other one of the wiring conductors; An insulating base having a bonding metallization layer, a second electrode for forming a capacitance opposing the first electrode on one main surface and electrically connected to the second electrode, and a first bonding metallization layer; An insulating plate which has a brazed frame-shaped second metallizing layer for bonding and which is bonded to the insulating base in a flexible state so as to form a sealed space with the other main surface of the insulating base; A pressure sensing device package, wherein the insulating plate is A frame-shaped protrusion is formed on the outer periphery of one main surface, a second metallization layer for adhesion is formed near the outer periphery of the protrusion, and an insulating substrate is formed on the inner periphery of the protrusion. And a frame-shaped insulating layer that is in contact with the other main surface. According to the package for a pressure detecting device of the present invention, a frame-shaped projection is formed on the outer peripheral portion of one main surface of the insulating plate, and the first metallization for the first bonding is provided near the outer periphery of the projected portion. Since the second metallizing layer for brazing brazed to the layer is applied, and the frame-shaped insulating layer that is in contact with the other main surface of the insulating base is applied to the inner peripheral portion of the protrusion, Even if external pressure is greatly applied to the insulating plate for a long period of time, the stress generated by the bending of the insulating plate is largely concentrated near the inner peripheral root of the protrusion and the insulating layer, and the insulating base and the insulating plate It does not significantly affect the brazing material joining to the brazing material. Next, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view illustrating an example of an embodiment of a package for a pressure detection device according to the present invention.
1 is an insulating base, 2 is an insulating plate, and 3 is a semiconductor element. The insulating substrate 1 is a laminate made of a ceramic material such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, or a glass-ceramic. If this is the case, an appropriate organic binder, a solvent, a plasticizer, and a dispersant are added to a ceramic raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide, and the mixture is mixed and formed into a slurry. A plurality of ceramic green sheets are obtained by forming into a sheet shape by adopting the doctor blade method, and thereafter, appropriate punching, laminating,
By cutting, a green ceramic molded body for the insulating substrate 1 is obtained, and the green ceramic molded body
It is manufactured by firing at a temperature of ° C. The insulating substrate 1 has a concave portion 1a for accommodating the semiconductor element 3 in the center of the lower surface thereof, and thereby functions as a container for accommodating the semiconductor element 3. The center of the bottom surface of the concave portion 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 a resin sealing such as an epoxy resin is formed in the concave portion 1a. The semiconductor element 3 is sealed by filling the material 4. In this example, the semiconductor element 3 is sealed by filling a resin sealing material 4 into the recess 1a. However, the semiconductor element 3 is provided with a lid made of metal or ceramic on the lower surface of the insulating base 1 in the recess 1a. May be sealed by joining them so as to close them. A plurality of metallized wiring conductors 5 connected to the respective electrodes of the semiconductor element 3 are led out from the mounting portion 1b. The metallized wiring conductor 5 and the respective electrodes of the semiconductor element 3 are connected to the solder bumps 6 and the like. By joining via an electrical connection member made of a conductive material, each electrode of the semiconductor element 3 and each metallized wiring conductor 5 are electrically connected, and the semiconductor element 3 is fixed to the mounting portion 1b. In this example, the electrodes of the semiconductor element 3 and the metallized wiring conductors 5 are connected via the solder bumps 6, but the electrodes of the semiconductor element 3 and the metallized wiring conductors 5 are connected to another type of electric wire such as a bonding wire. May be connected by a dynamic connection means. 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 electrode 7 and a second electrode 9, which will be described later.
A part thereof is led out to the lower surface of the outer periphery of the insulating base 1, and another part is electrically connected to the first electrode 7 and the second electrode 9. Then, each electrode of the semiconductor element 3 is electrically connected to the metallized wiring conductor 5 through an electrical connection means such as a solder bump 6 and the semiconductor element 3 is sealed with a resin sealing material 4. By joining a portion of the metallized wiring conductor 5 extending to the lower surface of the outer periphery of the insulating base 1 to a wiring conductor of the external electric circuit board via a conductive bonding material such as solder, the semiconductor element 3 housed inside is connected to the external electric circuit. It will be electrically connected. The metallized wiring conductor 5 is made of metal powder such as tungsten, molybdenum, copper, silver or the like, and is mixed with a metal powder such as tungsten by adding an appropriate organic binder, solvent, plasticizer, dispersant and the like. The metallized paste obtained as described above is applied in a predetermined pattern to a ceramic green sheet for the insulating substrate 1 by employing a conventionally known screen printing method, and is fired together with the green ceramic molded body for the insulating substrate 1 for insulation. A predetermined pattern is formed inside and on the surface of the base 1. The metallized wiring conductor 5 is provided on the surface of the metallized wiring conductor 5.
In order to prevent oxidation and corrosion of the metallized wiring conductor 5 and improve the bonding between the metallized wiring conductor 5 and the solder or the like, a nickel plating layer having a thickness of about 1 to 10 μm and a thickness of about 0.1 to 3 μm are usually used. Gold plated layers are sequentially applied. A first electrode 7 for forming a capacitance is attached to the center of the upper surface of the insulating base 1. The first electrode 7 is for forming a capacitance for a pressure-sensitive element together with a second electrode 9 described later, and is formed, for example, in a substantially circular pattern. One of the metallized wiring conductors 5a is connected to the first electrode 7, so that the electrode of the semiconductor element 3 is connected to the metallized wiring conductor 5a via an electrical connection means such as a solder bump 6. Then, the electrode of the semiconductor element 3 and the first electrode 7 are electrically connected. The first electrode 7 has a thickness of 10 to 50 μm.
Metallized paste made of metal powder such as tungsten or molybdenum, copper, silver, etc. of about m and mixed with a suitable organic binder, solvent, plasticizer and dispersant added to metal powder such as tungsten. A printing method is used to print and coat a ceramic green sheet for the insulating substrate 1 and bake it together with a green ceramic molded body for the insulating substrate 1 to form a predetermined pattern at the center of the upper surface of the insulating substrate 1. . The surface of the first electrode 7 is usually covered with a nickel plating layer having a thickness of about 1 to 10 μm in order to prevent the first electrode 7 from being oxidized and corroded. A substantially circular or substantially octagonal frame-shaped first bonding metallization layer 8 surrounding the first electrode 7 is applied to the outer peripheral portion of the upper surface of the insulating base 1. The first bonding metallization layer 8 functions as a base metal for bonding the insulating plate 2 to the insulating base 1, and the first bonding metallization layer 8 has a second electrode 9 on its lower surface and a second electrode 9 on its lower surface. The insulating plate 2 having the second bonding metallization layer 10 electrically connected thereto brazes the second bonding metallization layer 10 and the first bonding metallization layer 8 via a brazing material 11 such as silver-copper brazing. By doing so, it is joined so as to form a closed space with the insulating base 1. One of the metallized wiring conductors 5b is connected to the first bonding metallized layer 8 so that the electrodes of the semiconductor element 3 can be electrically connected to the metallized wiring conductor 5b such as solder bumps 6 or the like. And the second electrode 9 is electrically connected to the electrode of the semiconductor element 3. Such a first bonding metallization layer 8 is
A metallized paste made of metal powder such as tungsten, molybdenum, copper, silver, etc., mixed with an appropriate organic binder, solvent, plasticizer, and dispersant added to metal powder such as tungsten, and a conventionally known screen printing method is used. Adopted, printed and coated on a ceramic green sheet for the insulating substrate 1, and fired together with a green ceramic molded body for the insulating substrate 1 to form a frame-shaped predetermined pattern on the outer peripheral portion of the upper surface of the insulating substrate 1. . The surface of the first bonding metallization layer 8 is prevented from being oxidized and corroded on the surface of the first bonding metallization layer 8 and the bonding between the first bonding metallization layer 8 and the brazing material 11 is firmly formed. Usually, a nickel plating layer having a thickness of about 1 to 10 μm is applied. The insulating plate 2 joined to the upper surface of the insulating base 1 is made of a substantially square material made of a ceramic material such as a sintered body of aluminum oxide, a sintered body of aluminum nitride, a sintered body of mullite or a glass-ceramic. Or, it is a substantially flat plate such as a substantially octagonal or circular shape, and has a frame-shaped projection 2a on the outer peripheral portion of the inner main surface. Then, it functions as a so-called pressure detecting diaphragm that bends toward the insulating base 1 according to an external pressure. Incidentally, the thickness of the insulating plate 2 at the central portion thereof is set to 0.1 mm.
When the thickness is less than 01 mm, the mechanical strength is small, so that there is a great risk of being destroyed when a large external pressure is applied thereto. On the other hand, when the thickness of the central portion exceeds 5 mm. However, it becomes difficult to bend under a small pressure, and is not suitable as a diaphragm for detecting pressure. Therefore, the thickness of the central part of the insulating plate 2 is 0.
A range of 01 to 5 mm is preferred. If the height of the protrusion 2a is less than 0.01 mm, the gap formed between the insulating base 1 and the insulating plate 2 is too narrow, and the first electrode is not applied when pressure is applied to the insulating plate 2. The risk of contact between the first electrode 7 and the second electrode 9 increases. On the other hand, when the height of the protrusion 2a exceeds 5 mm, the static electricity formed between the first electrode 7 and the second electrode 9 is increased. The capacitance becomes small, and the sensitivity of the pressure-sensitive element decreases. Therefore, the height of the projection 2a is preferably in the range of 0.01 to 5 mm. If the insulating plate 2 is made of, for example, an aluminum oxide sintered body, an organic binder, a solvent, and a plastic material suitable for ceramic raw material powders such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide. A ceramic green sheet is obtained by adding and mixing a dispersing agent and a dispersing agent to form a slurry, and forming this into a sheet shape by employing a conventionally known doctor blade method. The green ceramic molded body for the insulating plate 2 is obtained by processing, laminating, and cutting, and the green ceramic molded body is manufactured by firing at a temperature of about 1600 ° C. On the lower surface of the insulating plate 2, a second electrode 9 for forming a capacitance facing the first electrode 7 is attached at the center. The second electrode 9 is for forming a capacitance for a pressure-sensitive element together with the above-mentioned first electrode 7, and is formed, for example, in a substantially circular pattern. The second electrode 9 has a thickness of 10 to 50 μm.
Metallized paste made of metal powder such as tungsten or molybdenum, copper, silver, etc. of about m and mixed with a suitable organic binder, solvent, plasticizer and dispersant added to metal powder such as tungsten. A printing method is used to print and coat the ceramic green sheet for the insulating plate 2 and fire it together with the green ceramic molded body for the insulating plate 2 to form a predetermined pattern at the center of the lower surface of the insulating plate 2. . The surface of the second electrode 9 is usually covered with a nickel plating layer having a thickness of about 1 to 10 μm in order to prevent the second electrode 9 from being oxidized and corroded. Further, a substantially circular or substantially octagonal frame-shaped second bonding metallization layer 10 electrically connected to the second electrode 9 is provided on the lower surface of the protrusion 2a of the insulating plate 2 at the inner peripheral edge of the protrusion 2a. From the outer periphery, for example, separated by about 0.05 mm or more. The second bonding metallization layer 10 functions as a bonding base metal layer for bonding the insulating plate 2 to the insulating base 1, and forms the second bonding metallization layer 10 and the first bonding metallization layer 8 with silver. The insulating base 1 and the insulating plate 2 are joined by brazing through a brazing material 11 such as copper brazing, and the first joining metallized layer 8 and the second joining metallized layer
10 is electrically connected. At this time, the first electrode 7 and the second electrode 9
They face each other with a closed space formed between the insulating base 1 and the insulating plate 2 therebetween, between them, the area of the first electrode 7 and the second electrode 9, and the first electrode 7 and the second electrode A predetermined capacitance is formed in accordance with the distance from the capacitor 9. And the insulating plate 2
When an external pressure is applied to the upper surface of the substrate, the insulating plate 2 bends toward the insulating base 1 in accordance with the pressure, and the distance between the first electrode 7 and the second electrode 9 changes. Since the capacitance with the second electrode 9 changes, it functions as a pressure-sensitive element that senses a change in external pressure as a change in capacitance. Then, the change in the capacitance is transmitted to the semiconductor element 3 housed in the concave portion 1a via the metallized wiring conductors 5a and 5b, and the magnitude of the external pressure is known by performing arithmetic processing on the semiconductor element 3. be able to. Such a second bonding metallization layer 10 is
Metallized paste made of metal powder such as tungsten, molybdenum, copper, silver, etc. with a thickness of about 10 to 50 μm, and obtained by adding and mixing an appropriate organic binder, solvent, plasticizer, and dispersant to metal powder such as tungsten. A known and well-known screen printing method is employed to print and coat a ceramic green sheet for the insulating plate 2, which is then fired together with the green ceramic molded body for the insulating plate 2, so that a predetermined surface is formed on the lower surface of the projection 2 a of the insulating plate 2. Formed in a pattern. The surface of the second bonding metallization layer 10 is prevented from being oxidized and corroded on the surface of the second bonding metallization layer 10, and the bonding between the second bonding metallization layer 10 and the brazing material 11 is improved. Usually, the thickness is 1 to 10
A nickel plating layer of about μm is applied. In order to bond the insulating plate 2 to the insulating base 1, a nickel plating layer having a thickness of about 1 to 10 μm is previously coated on the surfaces of the first bonding metallization layer 8 and the second bonding metallization layer 10, respectively. The insulating base 1 and the insulating plate are sandwiched between the first bonding metallization layer 8 and the second bonding metallization layer 10 with a brazing material foil made of silver-copper brazing having a thickness of about 10 to 200 μm. 2 and superposing them in a reducing atmosphere at a temperature of about 850 ° C. to melt the brazing material foil and braze the first bonding metallization layer 8 and the second bonding metallization layer 10. Adopted. A substantially circular frame-shaped insulating layer 12 which is in contact with the upper surface of the insulating base 1 is attached to the inner peripheral portion of the projection 2a. The insulating layer 12 is made of, for example, substantially the same ceramic material as the insulating plate 2. When the second bonding metallization layer 10 is brazed to the first bonding metallization layer 8 via the brazing material 11, The insulating plate 2 functions as a spacer member that keeps a predetermined distance between the first metallizing layer 8 and the second metallizing layer 10 when the insulating plate 2 is subjected to an external pressure. It functions as a stopper member for preventing the stress generated by the brazing material 11 from being applied. As described above, since the frame-shaped insulating layer 12 that is in contact with the upper surface of the insulating base 1 is applied to the inner peripheral portion of the projection 2a, the second bonding metallized layer 8 is When the metallized layer 10 is brazed with the brazing material 11 therebetween, the distance between the insulating base 1 and the insulating plate 2 is accurately defined by the insulating layer 12, so that the distance between the first electrode 7 and the second electrode 9 is reduced. It is possible to effectively prevent large variations from occurring. At the same time, when an external pressure is applied to the insulating plate 2, the stress generated by the bending of the insulating plate 2 is received by the insulating layer 12, so that the insulating plate 2 is largely bent by the external pressure. However, the stress generated by the deflection is largely concentrated near the root of the inner periphery of the projection 2a and on the insulating layer 12, and hardly acts on the brazing material 11. Therefore, according to the pressure detection device package of the present invention,
Even if an external pressure is applied to the insulating plate 2 for a long time, no plastic deformation occurs in the brazing material 11,
A pressure detection device capable of accurately detecting external pressure over a long period of time can be provided. If the thickness of the insulating layer 12 is less than 0.01 mm, a sufficient thickness of the brazing material 11 is secured between the first bonding metallization layer 8 and the second bonding metallization layer 10 to form a two-layer structure. It tends to be difficult to bond firmly,
When the thickness exceeds 0.2 mm, a gap is easily generated in the brazing material 11 when the first bonding metallization layer 8 and the second bonding metallization layer 10 are brazed through the brazing material 11, so that the insulating base 1 and There is a tendency that it is difficult to join the insulating plate 2 with the insulating plate 2 with high airtightness. Therefore, the thickness of the insulating layer 12 is 0.
A range of 01 to 0.2 mm is preferred. If the width of the insulating layer 12 is less than 0.05 mm, the insulating layer 12 is broken by stress generated by bending of the insulating plate 2 when an external pressure is applied to the insulating plate 2. The risk of
Is exceeded, the size of the package is increased due to the provision of such a wide insulating layer 12, and a small-sized pressure detecting device cannot be provided. Therefore, the width of the insulating layer 12 is 0.05
It is preferably in the range of １1 mm. The insulating layer 12 is made of an insulating paste obtained by adding a suitable organic binder and a solvent to the raw material powder substantially identical to the raw material powder contained in the ceramic green sheet for the insulating plate 2. The ceramic green sheet for the insulating plate 2 is printed and applied in a predetermined pattern by using a conventionally known screen printing method, and is fired together with the green ceramic molded body for the insulating plate 2 to thereby form an inner peripheral portion of the projection 2a. Is formed in a frame-like pattern. As described above, according to the pressure detecting device package of the present invention, the first electrode for forming the capacitance is provided on the other main surface of the insulating base 1 on which the semiconductor element 3 is mounted on one main surface. 7 and an insulating plate 2 having a second electrode 9 for forming a capacitance facing the first electrode 7 on an inner surface thereof in a flexible state so as to form a sealed space between the insulating plate 2 and the insulating base 1. Because of the joining, the container accommodating the semiconductor element 3 and the pressure-sensitive element are integrated, and as a result, the size of the pressure detection device can be reduced. Further, since the first electrode 7 and the second electrode 9 for forming the capacitance are connected to the semiconductor element 3 via the metallized wiring conductors 5a and 5b provided on the insulating base 1, the first electrode 7 and the second electrode 9 are formed. The electrode 9 can be connected to the semiconductor element 3 at a short distance, and as a result, an unnecessary capacitance generated between the metallized wiring conductors 5a and 5b is reduced to provide a highly sensitive pressure detecting device. Can be. Thus, according to the above-described package for the pressure detecting device, the semiconductor element 3 is mounted on the mounting portion 1b, and each electrode of the semiconductor element 3 is electrically connected to the metallized wiring conductor 5, and thereafter, the semiconductor By sealing the element 3, a compact and highly sensitive pressure detecting device is obtained. The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the scope of the present invention. As described above, according to the pressure detecting device package of the present invention, the other main surface of the insulating base having the mounting portion on which the semiconductor element is mounted on one main surface. A first electrode for forming a capacitance is provided at a central portion, and an insulating plate having a second electrode for forming a capacitance opposed to the first electrode is formed so as to form a closed space between the insulating plate and the insulating base. The pressure sensing element is formed integrally with the package accommodating the semiconductor element, and as a result, the pressure sensing device can be reduced in size and the pressure sensing electrode and the semiconductor can be joined together. Unnecessary capacitance generated between these wires can be reduced by shortening the wires connecting the elements. Further, a frame-shaped projection is formed on the outer periphery of one main surface of the insulating plate, and a second bonding metallization layer brazed to the first bonding metallization layer of the insulating base near the outer periphery of the projection. Is attached, and an insulating layer that is in contact with the other main surface of the insulating base is attached to the inner peripheral portion of the protrusion, so that an external pressure is greatly applied to the insulating plate for a long period of time. Even if the bending occurs, the stress generated by the bending of the insulating plate is largely concentrated near the inner peripheral root of the protrusion and on the insulating layer, and does not significantly act on the brazing material joining the insulating base and the insulating plate. Therefore, even if an external pressure is applied to the insulating plate over a long period of time, a plastic deformation does not occur in the brazing material, and a pressure detecting device capable of accurately detecting the external pressure over a long period of time is provided. can do.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing an example of an embodiment of a package for a pressure detecting device according to the present invention. FIG. 2 is a sectional view showing a conventional pressure detecting device. [Description of Signs] 1 ... Insulating base 2 ... Insulating plate 2a ... Protrusion 3 ... Semiconductor element 7 ... First electrode 8 ...・ First joining metallization layer 9 ・ ・ ・ ・ ・ ・ Second electrode 10 ・ ・ ・ ・ ・ ・ Second joining metallization layer 11 ・ ・ ・ ・ ・ ・ Brazing material 12 ・ ・ ・ ・ ・ ・ Insulating layer

Claims (1)

Claims: 1. A mounting portion having a plurality of wiring conductors inside and on a surface and mounting a semiconductor element on one main surface, and electrically connecting one of the wiring conductors on the other main surface. An insulating base having a first electrode for forming a capacitance, which is electrically connected, and a frame-shaped first metallizing layer surrounding the first electrode and electrically connected to another one of the wiring conductors; A frame-shaped one electrode is electrically connected to the second electrode and the second electrode for forming a capacitance opposing the first electrode on the one main surface, and is brazed to the first bonding metallization layer. A pressure detecting device comprising: a second bonding metallization layer; and an insulating plate bonded to the insulating base in a flexible state so as to form a sealed space with the other main surface of the insulating base. Package, wherein the insulating plate is provided outside of one of its main surfaces. The second bonding metallization is attached near the outer periphery of the protrusion, and the inner peripheral portion of the protrusion contacts the other main surface of the insulating base. A package for a pressure detecting device, wherein a frame-shaped insulating layer is attached.