JP2005156410A - Package for pressure-detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a package for a pressure-detecting device which is compact and has high sensitivity, capable of accurately detecting the external pressure. <P>SOLUTION: The package for the pressure-detecting device is equipped with an insulating substrate 1, having a section 1b to be mounted in its one main surface on which a semiconductor element 3 is mounted; a projection section which is formed at the center section of the other main surface of the insulating substrate 1; a plurality of wiring conductors 5, which are disposed on and inside the insulating substrate 1 and by which electrodes of the semiconductor element 3 are electrically connected, respectively; an insulating plate 2, which is bonded to the periphery of the projecting section of the insulating substrate 1 flexibly so as to form a sealed space between itself and the projecting section; a first electrode 7, which is attached to the upper surface of the projecting section in the sealed space, electrically connected to one of the wiring conductors 5 and is used for forming a capacitor; a second electrode 9, which is attached to the inner main surface of the insulating plate 2 so as to be opposite to the first electrode 7, electrically connected to another wiring conductor 5 and used for making up the capacitor; and a step section 2a, which is formed extending over the entire circumference of the inner main surface of the insulating plate 2 and is in contact with the upper surface of the projection section. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pressure detection device package used in a pressure detection device for detecting pressure.

  Conventionally, a capacitance type pressure detection device is known as a pressure detection device for detecting pressure. For example, as shown in a sectional view in FIG. 5, this capacitance type pressure detection device is accommodated in a capacitance type pressure sensitive element 22 and a package 28 on a wiring substrate 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 recess in which one electrode 23 for forming a capacitance is attached at the center of the upper surface, and the upper surface of the insulating base 24. And an insulating plate 26 which is joined in a flexible state so as to form a sealed space between the insulating base 24 and the other electrode 25 for forming a capacitance on the lower surface. Each of the capacitance forming electrodes 23 and 25 is composed of an external lead terminal 27 for electrically connecting to the outside, and each capacitance is formed by bending the insulating plate 26 according to the external pressure. The capacitance formed between the electrodes 23 and 25 for use changes. Then, an external pressure can be detected by performing arithmetic processing on the change of the electrostatic capacitance with the semiconductor element 29 for arithmetic operation.

  However, according to this conventional pressure detecting device, since the pressure sensitive element 22 and the semiconductor element 29 are individually mounted on the wiring board 21, the pressure detecting device is enlarged and the pressure detecting electrode 23, The wiring between the semiconductor element 29 and the semiconductor element 29 becomes long, and an unnecessary capacitance is formed between the long wirings, so that the sensitivity is low.

  Therefore, as shown in a cross-sectional view in FIG. 4, an insulating base 11 having a mounting portion 11 b on which one of the main surfaces of the semiconductor element 13 is mounted, and a surface of and inside the insulating base 11 are provided. A plurality of wiring conductors 15 to which the respective electrodes are electrically connected, and capacitance formation that is attached to the central portion of the other main surface of the insulating base 11 and is electrically connected to one of the wiring conductors 15 An insulating plate 12 joined in a flexible state so as to form a sealed space between the first electrode 17 for use and the other main surface of the insulating base 11 and the central portion of the main surface, and the insulating plate 12 Pressure detection comprising a second electrode 19 for forming a capacitance, which is attached to the inner main surface of the plate 12 so as to face the first electrode 17 and is electrically connected to the other one of the wiring conductors 15. A device package has been proposed (see Patent Document 1 below).

  According to this pressure detection device package, the first electrode 17 for forming a capacitance is provided on the other main surface of the insulating base 11 having the mounting portion 11b on which the semiconductor element 13 is mounted on one main surface, The insulating plate 12 having the second electrode 19 for forming a capacitance facing the first electrode 17 on the inner surface is flexible so as to form a sealed space between the other main surface of the insulating substrate 15. Since the pressure sensitive element is integrally formed in the package that accommodates the semiconductor element 13, the pressure detecting device can be reduced in size and the pressure detecting electrode and the semiconductor element 13 can be reduced. It is possible to reduce the unnecessary electrostatic capacitance generated between these wirings by shortening the wiring for connecting the wires.

  Conventionally, the first electrode 17 of these pressure detection device packages is made of metal powder metallization such as tungsten, molybdenum, copper, silver, etc., and an appropriate organic binder, solvent, plasticizer, and dispersant are applied to the metal powder such as tungsten. The metallized paste obtained by addition and mixing is printed on a ceramic green sheet for the insulating substrate 11 by using a conventionally known screen printing method, and is fired together with a green ceramic molded body for the insulating substrate 11 to thereby insulate the insulating substrate. 11 is formed in a predetermined pattern at the center of the upper surface.

  The second electrode 19 is made of metal powder metallization such as tungsten, molybdenum, copper, or silver, and is obtained by adding and mixing an appropriate organic binder, solvent, plasticizer, and dispersant to metal powder such as tungsten. Is applied to a ceramic green sheet for the insulating plate 12 by using a well-known screen printing method, and is fired together with a green ceramic molded body for the insulating plate 12 to form a predetermined pattern of the insulating plate 12. The

  In addition, in order to use the first electrode 17 and the second electrode 19 for forming a capacitance, it is necessary to form a certain region between the first electrode 17 and the second electrode 19. 11 or the insulating plate 12 is formed with a frame-like protrusion 12b on the outer peripheral portion thereof, thereby forming a sealed space for forming a capacitance between the insulating base 11 and the insulating plate 12.

Further, the insulating base 11 and the insulating plate 12 are formed with a first bonding metallized layer 18 and a second bonding metallized layer 20 on the outer peripheral part or the frame-shaped protrusion 12b. And the second bonding metallization layer 20 were bonded by a brazing material or the like.
JP 2001-356064 A

  However, according to the conventional package for a pressure detection device, the brazing material made of silver-copper brazing that joins the insulating base 11 and the insulating plate 12 is likely to be plastically deformed by a large stress. Is greatly applied over a long period of time, the stress generated by the bending of the insulating plate 12 acts greatly on the inner peripheral edge of the brazing material joining the insulating base 11 and the insulating plate 12, and plastic deformation occurs in the brazing material. As a result, the insulating plate 12 does not return to its original position even when the pressure is released, and it is difficult to accurately detect the external pressure.

  Accordingly, the present invention has been devised in view of such conventional problems, and an object thereof is to provide a pressure detection device capable of accurately detecting an external pressure over a long period of time.

  The package for a pressure detection device of the present invention includes an insulating base having a mounting portion on which a semiconductor element is mounted on one main surface, a convex portion formed at a central portion of the other main surface of the insulating base, and the insulating The insulation in a flexible state so as to form a sealed space between a plurality of wiring conductors arranged on the surface and inside of the base body and electrically connected to the electrodes of the semiconductor element. An insulating plate bonded around the convex portion of the base, and an electrostatic capacity forming first electrode that is attached to the upper surface of the convex portion in the sealed space and is electrically connected to one of the wiring conductors. One electrode and a second electrode for forming a capacitance that is attached to the inner main surface of the insulating plate so as to face the first electrode and is electrically connected to the other one of the wiring conductors And the upper surface of the convex portion formed on the outer peripheral portion of the inner main surface of the insulating plate over the entire circumference Characterized in that it comprises the abutted stepped portion.

  According to the package for a pressure detection device of the present invention, an insulating base having a mounting portion on which a semiconductor element is mounted on one main surface, a convex portion formed at the center of the other main surface of the insulating base, and an insulating A surface of the base body and an inside of the insulating base body in a flexible state so as to form a sealed space between a plurality of wiring conductors that are electrically connected to each electrode of the semiconductor element and a convex portion. An insulating plate joined around the convex portion, a first electrode for forming a capacitance that is attached to the upper surface of the convex portion in the sealed space and electrically connected to one of the wiring conductors, and an insulating plate A second electrode for forming a capacitance that is attached to the inner main surface of the first electrode so as to face the first electrode and is electrically connected to the other one of the wiring conductors, and an inner main surface of the insulating plate A step portion that is formed over the entire circumference and is in contact with the upper surface of the convex portion. As narrow a distance between the first electrode and the second electrode can be made high sensitivity of the pressure detection.

  Moreover, even if external pressure is applied to the insulating plate for a long period of time, the stress generated by the bending of the insulating plate can be concentrated on the step portion of the insulating plate in contact with the convex portion. It is possible to effectively prevent the brazing material from being plastically deformed by acting on the brazing material joining the insulating base and the insulating plate. As a result, when the pressure is released, the insulating plate can be satisfactorily restored to the original position, and the detection accuracy of the external pressure can be maintained well over a long period.

  Furthermore, when the insulating plate is joined to the insulating base, the gap between the first electrode and the second electrode can be made extremely accurate with little variation by bringing the step portion into contact with the convex portion. The sensitivity of can be made very high accuracy. In addition, the interval between the joint portions of the insulating plate and the insulating base can be adjusted with extremely high accuracy, and the bonding between the insulating base and the insulating plate can be made extremely strong with little variation in the bonding strength.

  Next, a pressure detection device package according to 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 detecting device package according to the present invention. In FIG. 1, 1 is an insulating substrate, 2 is an insulating plate, 3 is a semiconductor element, 7 is a first electrode, Reference numeral 9 denotes a second electrode.

  The insulating 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, or a glass-ceramic.

  When the insulating substrate 1 is made of, for example, 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, and then these ceramic green sheets are appropriately punched and laminated. The green ceramic molded body for the insulating substrate 1 is obtained by cutting, and the green ceramic molded body is manufactured by firing at a temperature of about 1600 ° C.

  The insulating base 1 has a concave portion 1a for accommodating the semiconductor element 3 formed on one main surface (the lower surface in FIG. 1), 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 resin sealing material 4 into the recess 1a. However, the semiconductor element 3 has a lid made of metal, ceramics, or the like on the lower surface of the insulating base 1. You may seal by making it join so that 1a may be plugged up.

  In addition, a plurality of wiring conductors 5 connected to the respective electrodes of the semiconductor element 3 are led out to the mounting portion 1b, and electrical connection means such as solder bumps 6 are connected to the wiring conductors 5 and the respective electrodes of the semiconductor element 3. By connecting them, each electrode of the semiconductor element 3 and each wiring conductor 5 are electrically connected, and the semiconductor element 3 is fixed to the mounting portion 1b. In this example, the electrode of the semiconductor element 3 and the wiring conductor 5 are connected via the solder bumps 6. However, the electrode of the semiconductor element 3 and the wiring conductor 5 are connected to other types of electrical connections such as bonding wires. It may be connected by means.

  The 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 described later, and a part of the wiring conductor 5 is an outer periphery of the insulating base 1. It is led out to the lower surface of the part, 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 these wiring conductors 5 through electrical connection means such as solder bumps 6 and the semiconductor element 3 is sealed with a resin sealing material 4. The portion of the conductor 5 led to the lower surface of the outer peripheral portion of the insulating base 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 becomes an external electric circuit. It will be electrically connected.

  Such a 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, etc. to metal powder such as tungsten. The paste is applied in a predetermined pattern to a ceramic green sheet for the insulating substrate 1 by using a conventionally known screen printing method, and this is fired together with a green ceramic molded body for the insulating substrate 1 to synthesize the inside of the insulating substrate 1. In addition, a predetermined pattern is formed on the surface.

  In order to prevent the wiring conductor 5 from being oxidized and corroded on the surface of the wiring conductor 5 and to improve the bonding between the wiring conductor 5 and solder or the like, for example, nickel having a thickness of about 1 to 10 μm is used. It is preferable that a plating layer and a gold plating layer having a thickness of about 0.1 to 3 μm are sequentially deposited.

  The insulating substrate 1 has a convex portion at the center of the other main surface (upper surface in FIG. 1), and a first electrode 7 for forming a capacitance is deposited on the upper surface. 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 in, for example, a circular pattern. A wiring conductor 5a, which is one of the wiring conductors 5, is connected to the first electrode 7. The electrode of the semiconductor element 3 is connected to the other end of the wiring conductor 5a via an electrical connection means such as a solder bump 6. Thus, the electrode of the conductor element 3 and the first electrode 7 are electrically connected.

  The first electrode 7 is made of metal powder metallization such as tungsten, molybdenum, copper, and silver having a thickness of about 10 to 50 μm. For example, an organic binder, solvent, plasticizer, dispersion suitable for metal powder such as tungsten. The metallized paste obtained by adding and mixing the agent is printed and applied to the ceramic green sheet for the insulating substrate 1 using a conventionally known screen printing method, and is fired together with the green ceramic molded body for the insulating substrate 1 A predetermined pattern is formed at the center of the upper surface of the insulating substrate 1. In addition, in order to prevent the first electrode 7 from being oxidatively corroded on the surface of the first electrode 7, for example, a nickel plating layer having a thickness of about 1 to 10 μm may be deposited.

  Further, a frame-shaped first bonding metallization layer 8 is attached to the outer peripheral portion of the upper surface of the insulating substrate 1 over the entire periphery, and the lower peripheral portion of the lower surface of the insulating plate 2 is attached to the first bonding metallized layer 8. The second metallization layer 10 for bonding is bonded via a brazing material such as a silver-copper brazing material, whereby a sealed space is formed between the insulating base 1 and the insulating plate 2.

  A wiring conductor 5b, which is one of the wiring conductors 5, is connected to the first bonding metallization layer 8. An electrode of the semiconductor element 3 is connected to the other end of the wiring conductor 5b with an electrical connection means such as a solder bump 6. Thus, the electrode of the semiconductor element 3 and the second electrode 9 are electrically connected.

  Such a first bonding metallization layer 8 is made of metal powder metallization such as tungsten, molybdenum, copper, and silver. For example, an appropriate organic binder, solvent, plasticizer, and dispersant are added to and mixed with metal powder such as tungsten. The metallized paste obtained in this manner is printed and applied to a ceramic green sheet for the insulating substrate 1 using a conventionally known screen printing method, and is fired together with a green ceramic molded body for the insulating substrate 1 to thereby form the insulating substrate 1. A predetermined frame-like pattern is formed on the outer periphery of the upper surface. 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 is strengthened. In addition, a nickel plating layer having a thickness of about 1 to 10 μm is preferably applied.

  Further, the height of the convex portion of the insulating substrate 1 is preferably 10 to 200 μm. As a result, it is possible to effectively suppress the stress generated by the bending of the insulating plate 2 from acting greatly on the brazing material joining the insulating base 1 and the insulating plate 2, and to effectively cause plastic deformation in the brazing material. Can be prevented.

  As shown in FIG. 1, the convex portion may consist of a part of the insulating base 1, and the convex portion may be formed by attaching a plate-like insulator to the insulating base 1. . When an insulator is attached to the insulating substrate 1, it is possible to easily form a surface with higher flatness by attaching the insulator to the insulating substrate 1 after the insulator is flattened by polishing or the like. It is possible to improve the flatness of the one electrode 7 and further improve the accuracy of the pressure inspection.

  Moreover, the convex part may be formed with the conductor. For example, the first electrode 7 can be formed after forming a metallized layer to be a convex portion on the insulating substrate 1. Alternatively, a thick metallization layer may be formed on the insulating substrate 1 so that the convex portion and the first electrode 7 are integrally formed. Thus, by forming the convex portion with a conductor such as metallized, the contact portion of the convex portion with the stepped portion 2a is appropriately deformed, and the stress applied to the stepped portion 2a can be effectively absorbed by the convex portion. .

  The insulating plate 2 bonded to the upper surface of the insulating substrate 1 is a square or octagonal shape 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. , A flat plate shape such as a circular shape, and has a frame-shaped step portion 2a having a height of 0.01 to 5 mm on the outer peripheral portion of the lower surface thereof. And the center part enclosed by the level | step-difference part 2a functions as what is called a diaphragm for pressure detections bent to the insulating base | substrate 1 side according to an external pressure.

  The insulating plate 2 tends to have a low mechanical strength when the thickness of the central portion is less than 0.01 mm. On the other hand, when the thickness of the central portion exceeds 5 mm, it becomes difficult to bend with a small pressure, and it is difficult to detect the pressure with high accuracy. Therefore, the thickness of the central part of the insulating plate 2 is preferably in the range of 0.01 to 5 mm.

  Further, the height of the stepped portion 2a is preferably 0.1 mm or more in order to prevent plastic deformation of the brazing material joining the insulating base 1 and the insulating plate 2, and the height of the stepped portion 2a is 0.00. In the case of less than 1 mm, when the central portion of the insulating plate 2 is greatly bent due to external pressure, the stress generated by the bending acts greatly on the inner peripheral edge of the brazing material via the inner peripheral edge of the stepped portion 2a. It is easy for plastic deformation to occur in the brazing filler metal. Further, when the height of the stepped portion 2a exceeds 5 mm, the thickness of the pressure detection device package tends to be too thick in order to form the stepped portion 2a having such a height. Accordingly, the height of the stepped portion 2a is preferably in the range of 0.1 to 5 mm.

  When such an insulating plate 2 is made of, for example, an aluminum oxide sintered body, an organic binder, a solvent, a plasticizer, a dispersion suitable for ceramic raw material powders such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide are used. A ceramic green sheet is obtained by adding a mixing agent to form a mud and forming it into a sheet using a conventionally known doctor blade method, and then punching or laminating the ceramic green sheet appropriately. The raw ceramic molded body for the insulating plate 2 is obtained by processing and cutting, and the raw ceramic molded body is manufactured by firing at a temperature of about 1600 ° C.

  Further, a second electrode 9 for forming a capacitance facing the first electrode 7 is attached to the lower surface of the insulating plate 2 at the center thereof. The second electrode 9 is used to form a capacitance for the pressure sensitive element together with the first electrode 7 described above, and is formed in a circular pattern, for example.

  Such a second electrode 9 is made of metal powder metallization of tungsten, molybdenum, copper, silver or the like having a thickness of about 10 to 50 μm, and an appropriate organic binder, solvent, plasticizer, or dispersant is applied to the metal powder such as tungsten. The metallized paste obtained by addition and mixing is applied to a ceramic green sheet for the insulating plate 2 by employing a conventionally known screen printing method, and is fired together with the green ceramic molded body for the insulating plate 2 to synthesize the insulating plate. 2 is formed in a predetermined pattern at the center of the lower surface. The surface of the second electrode 9 is preferably coated 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 circular or octagonal frame-like second bonding metallization layer 10 electrically connected to the second electrode 9 is deposited on the lower surface of the stepped portion 2a of the insulating plate 2. The second bonding metallization layer 10 functions as a bonding base metal layer for bonding the insulating plate 2 to the insulating substrate 1, and the second bonding metallization layer 10 and the first bonding metallization layer 8 are silver- The insulating base 1 and the insulating plate 2 are bonded by bonding via a brazing material such as copper brazing, and the first bonding metallized layer 8 and the second bonding metallized layer 10 are electrically connected.

  At this time, the first electrode 7 and the second electrode 9 are opposed to each other with a sealed space formed between the insulating base 1 and the insulating plate 2 interposed therebetween. A predetermined capacitance is formed according to the area of the second electrode 9 and the distance between the first electrode 7 and the second electrode 9. When an external pressure is applied to the upper surface of the insulating plate 2, the insulating plate 2 is bent toward the insulating base 1 in accordance with the pressure, and the distance between the first electrode 7 and the second electrode 9 is changed. Since the capacitance between the electrode 7 and 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 electrostatic capacity is transmitted to the semiconductor element 3 accommodated in the recess 1a through the wiring conductors 5a and 5b, and this is processed by the semiconductor element 3 so as to know the magnitude of the external pressure. Can do.

  Such a second bonding metallization layer 10 is made of metal powder metallization of tungsten, molybdenum, copper, silver or the like having a thickness of about 10 to 50 μm, and suitable organic binder, solvent, plasticizer, metal powder such as tungsten, A metallized paste obtained by adding and mixing a dispersant is applied and applied to a ceramic green sheet for the insulating plate 2 using a conventionally known screen printing method, and is fired together with a green ceramic molded body for the insulating plate 2 Thus, a predetermined pattern is formed on the lower surface of the stepped portion 2a of the insulating plate 2.

  In order to prevent the second bonding metallization layer 10 from being oxidatively corroded on the surface of the second bonding metallization layer 10 and to improve the bonding between the second bonding metallization layer 10 and the brazing material, A nickel plating layer having a thickness of about 1 to 10 μm is preferably applied.

  Further, in order to join the insulating plate 2 to the insulating base 1, for example, a nickel plating layer having a thickness of about 1 to 10 μm is previously deposited on the surfaces of the first joining metallized layer 8 and the second joining metallized layer 10, respectively. Insulating substrate 1 and insulating plate 2 with a brazing material foil made of silver-copper brazing having a thickness of about 10 to 200 μm interposed between metallizing layer 8 for first bonding and metallizing layer 10 for second bonding. And a method of brazing the metallized layer 8 for first bonding and the metallized layer 10 for second bonding by heating them to a temperature of about 850 ° C. in a reducing atmosphere to melt the brazing material foil. Is done.

  Further, as shown in FIG. 1, the insulating plate 2 is preferably formed with a protruding portion 2 b protruding from a portion where the second bonding metallization layer is applied. Accordingly, it is possible to effectively prevent the brazing material between the first bonding metallization layer and the second bonding metallization layer from flowing out and coming into contact with the first electrode 7. 2 can be brought closer to the first electrode 7, and the pressure detection device package can be further downsized. Further, the brazing material between the first bonding metallization layer and the second bonding metallization layer can be thinned, and the thermal expansion in the height direction of the brazing material is reduced, and stress is applied to the insulating substrate 1 and the insulating plate 2. Can be effectively prevented.

  Further, by forming the protruding portion 2b, it is possible to increase the distance between the stepped portion 2a and the joint portion of the brazing material and to prevent the stress due to the bending of the insulating plate 2 from acting on the brazing material. Since the height of the stepped portion 2a can be made thinner than 0.1 mm, the distance between the first electrode 7 and the second electrode 9 can be made small, can do.

  The step 2a of the insulating plate 2 may be in contact with the upper surface of the outer peripheral portion of the first electrode 7 as shown in FIG. 1, or as shown in the sectional view of the pressure detecting device package of FIG. You may make it contact | abut directly on the upper surface of the convex part of the insulation base | substrate 1 around the electrode 7. FIG. When the stepped portion 2a is in direct contact with the upper surface of the convex portion, the distance between the first electrode 7 and the second electrode 9 can be reduced by the thickness of the first electrode 7, so that the pressure sensing device with higher sensitivity can be used. It can be a package.

  1 and 2, the step portion 2a is formed in a part of the insulating plate 2. However, it may be formed by a metallized layer or the like. For example, the pressure detection device package of FIG. As shown in the cross-sectional view, a stepped portion 2 a made of a metallized layer may be formed around the second electrode 9 so as to abut on the insulating substrate 1. By forming the stepped portion 2a with the metallized layer as described above, the stress applied to the stepped portion 2a can be effectively absorbed by the stepped portion 2a being appropriately deformed, and the stepped portion 2a is formed with the metalized layer. Thus, it is easy to form a thin film, and the distance between the first electrode 7 and the second electrode 9 can be made smaller to increase the sensitivity.

  In addition, when this level | step-difference part 2a consists of a metallization layer and contact | abuts to the 1st electrode 7 grade | etc., The 2nd electrode 9 and the 2nd joining so that the 1st electrode 7 and the 2nd electrode 9 may not short-circuit. What is necessary is just to provide a space | gap part between the connection part with a metallizing layer, and the level | step-difference part 2a.

  Thus, according to the package for a pressure detection device of the present invention, the first electrode 7 for forming a 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. In addition, the insulating plate 2 having the second electrode 9 for forming a capacitance facing the first electrode 7 on the inner surface is joined in a flexible state so as to form a sealed space with the insulating base 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 miniaturized. In addition, since the first electrode 7 and the second electrode 9 for forming capacitance are connected to the semiconductor element 3 via the wiring conductors 5a and 5b provided on the insulating substrate 1, the first electrode 7 and the second electrode 9 can be connected to the semiconductor element 3 at a short distance, and as a result, it is possible to provide a highly sensitive pressure detecting device by reducing unnecessary capacitance generated between the wiring conductors 5a and 5b. .

  Thus, according to the above-described package for a pressure detection device, the semiconductor element 3 is mounted on the mounting portion 1b, and each electrode of the semiconductor element 3 and the wiring conductor 5 are electrically connected, and then the semiconductor element 3 is sealed. By stopping, the pressure detection device is small and has high sensitivity.

  In addition, this invention is not limited to an example of the above-mentioned embodiment, It cannot be overemphasized that a various change is possible if it is a range which does not deviate from the summary of this invention.

It is sectional drawing which shows an example of embodiment of the package for pressure detection apparatuses of this invention. It is sectional drawing which shows the other example of embodiment of the package for pressure detection apparatuses of this invention. It is sectional drawing which shows the other example of embodiment of the package for pressure detection apparatuses of this invention. It is sectional drawing which shows the package for the conventional pressure detection apparatus. It is sectional drawing which shows the package for the conventional pressure detection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Insulation base | substrate 2 ... Insulation board 2a ... Step part 3 ... Semiconductor element 5 ... Wiring conductor 7 ... First electrode 9- .... Second electrode

Claims (1)

An insulating base having a mounting portion on which a semiconductor element is mounted on one main surface; a convex portion formed at a central portion of the other main surface of the insulating base; and a surface and inside of the insulating base; Bonded around the convex portion of the insulating base in a flexible state so as to form a sealed space between the plurality of wiring conductors to which the respective electrodes of the semiconductor element are electrically connected and the convex portion. An insulating plate, a first electrode for forming a capacitance that is attached to an upper surface of the convex portion in the sealed space and is electrically connected to one of the wiring conductors, and an inner side of the insulating plate. A second electrode for forming a capacitance which is attached to the main surface so as to face the first electrode and is electrically connected to the other one of the wiring conductors; and a main surface inside the insulating plate And a step portion that is formed over the entire circumference and abutted against the upper surface of the convex portion. Package for pressure detection apparatus according to claim.

Images