JP2010197057A - Base substance for pressure detection device and the pressure detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a base substance for a pressure detection device for detecting an external pressure with high accuracy, and the pressure detection device. <P>SOLUTION: The base substance for the pressure detection device includes: an insulating base substance 1, made up of a sintered body having an internal space 1a; and an upper electrode 3 and a lower electrode 4 provided on the top surface and the undersurface of the internal space 1a; has a flexible region 1e on at least one of the top surface and the undersurface, and moreover includes: a shield layer 5 formed on the external surface of the flexible region 1e in such a way as to cover the upper electrode 3 and the lower electrode 4 in plan view; shield conductors 6 which are arranged in such a way as to surround the internal space 1a and the upper electrode 3 and the lower electrode 4, independent electrically from the shield layer 5, and connected electrically to at least one of the conductor layers 2 for electrodes; and a connection part 7 for electrically connecting the shield layer 5 formed on the surface of the insulating base substance 1 with a conductor layer 2 for an electrode. Since a plated layer is not adhered onto the surface of the shield layer, a pressure detection device capable of shielding noise and having a high pressure detection accuracy is obtained. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a capacitance type pressure detection substrate and a pressure detection device for detecting pressure.

  Conventionally, there is a capacitance type pressure detection device as a pressure detection device for detecting pressure. As a base for a pressure detection device used in this capacitance type pressure detection device, a predetermined interval is provided between an insulating substrate made of ceramics having a first electrode for forming a capacitance formed on the surface, and the insulating substrate. A diaphragm made of ceramics provided with a space and bonded in a flexible manner to the surface of the insulating substrate and having a second electrode for forming a capacitance so as to face the first electrode It has been known. The insulating substrate, the diaphragm, and the spacer between them are integrally formed, thereby forming an internal space sealed in the insulating base. When the diaphragm bends due to external pressure fluctuation, the distance between the first electrode and the second electrode changes, and the capacitance between them changes, so that pressure fluctuation is detected by the change in capacitance. (Refer to Patent Document 1). The first electrode and the second electrode of such a pressure detection device base are connected to an electronic component mounted on the pressure detection device base or on an external circuit board together with the pressure detection device base, By performing arithmetic processing with this electronic component, a pressure detection device is obtained in which a change in capacitance is converted into a change in pressure value. For this reason, a wiring layer for connecting to an electronic component or an external circuit board is formed on the base for the pressure detection device, and the surface of the electrode conductor layer formed on the outer surface of the substrate is used for corrosion prevention and electronic components. For the wettability of solder or the like for connection to an external circuit board, a plating layer such as nickel or gold is applied.

  In such a capacitance-type pressure detection device, it is impossible to detect external pressure satisfactorily due to the influence of noise caused by electronic components, electronic devices, etc. mounted around the pressure detection device. Is concerned. In view of this, it is conceivable that a shield electrode is formed around the internal space in which the first electrode and the second electrode are formed, thereby blocking noise that enters from the outside. Such a shield electrode is electrically connected to a wiring layer having a ground potential in order to better block noise.

JP 2006-47327 A

  However, the base for a pressure detection device as described above is a shield electrode that is electrically connected to the electrode conductor layer via the wiring layer when the plating layer is deposited on the surface of the electrode conductor layer by the electrolytic plating method. The plating layer is also deposited on the exposed surface of the film. Although the shield electrode is also formed on the outer surface of the diaphragm, the plating layer deposited on the shield electrode on the diaphragm is work-hardened due to repeated deflection of the diaphragm due to external pressure fluctuations, and against the pressure fluctuations. As the amount of deflection of the diaphragm changes, the rate of change of the capacitance also changes, and there is a possibility that the external pressure cannot be detected accurately.

  On the other hand, a method is conceivable in which the shield electrode formed on the upper surface of the diaphragm is covered with a masking tape and a plating layer is deposited by an electrolytic plating method or an electroless plating method. However, with this method, not only is the masking tape affixed and peeled off, but in the case of a high-sensitivity pressure sensor substrate with a thin diaphragm, the masking tape is removed when the masking tape is peeled from the diaphragm. Cracks are likely to occur, and there is a possibility of a pressure detection device that cannot accurately detect external pressure.

  The present invention has been devised in view of the above problems of the prior art, and an object of the present invention is to provide a base for a pressure detection device and a pressure detection device capable of accurately detecting an external pressure.

  The substrate for a pressure detection device of the present invention has an internal space having an upper surface and a lower surface facing each other, and an insulating substrate made of a sintered body having a plurality of electrode conductor layers on the surface, and the internal space through the internal space. A base for a pressure detection device, comprising: an upper electrode and a lower electrode facing each other, and having a flexible region that bends when pressure is applied from the outside to at least one of the upper surface and the lower surface. The outer surface is disposed so as to cover the upper electrode or the lower electrode in a plan view, and the shield layer electrically independent from the upper electrode and the lower electrode, the internal space, the upper electrode, and the lower electrode It is disposed so as to surround a side electrode, and is electrically independent from the upper electrode, the lower electrode, and the shield layer, and is electrically connected to at least one of the electrode conductor layers. A shield conductor and a connecting portion disposed in a region other than the flexible region on the surface of the insulating base for electrically connecting the shield layer and the electrode conductor layer. It is what.

  The pressure detection device substrate of the present invention has an internal space having an upper surface and a lower surface facing each other, and an insulating substrate made of a sintered body having a plurality of electrode conductor layers on the surface, and the internal space through the internal space. An upper electrode and a lower electrode facing each other, and having at least one of the upper surface and the lower surface a flexible region that is bent when pressure is applied from the outside, wherein the flexible substrate A shield layer disposed on the outer surface of the region so as to cover the upper electrode or the lower electrode in plan view, and electrically independent of the upper electrode and the lower electrode; the internal space; and the upper electrode and A shield conductor disposed so as to surround the lower electrode, electrically independent of the upper electrode and the lower electrode, and electrically connected to the shield layer; and a surface of the insulating substrate And it is characterized in that it comprises a connecting portion for electrically connecting the electrode conductor layer and the shield layer disposed in a region other than the flexible region.

  In the pressure detection device substrate of the present invention, in each of the above-described configurations, the connection portion is configured such that a connection conductor electrically connected to the electrode conductor layer is disposed in proximity to the shield layer. It is a feature.

  Further, the pressure detection device substrate of the present invention is characterized in that, in each of the above configurations, the shield layer and the electrode conductor layer are electrically connected to each other through a conductive connection member in the connection portion. To do.

  The pressure detection device of the present invention is characterized in that an electronic component is electrically connected to the electrode conductor layer of the base for a pressure detection device of the present invention having the above-described configuration.

  According to the pressure detection device substrate of the present invention, the shield layer is disposed on the outer surface of the flexible region so as to cover the upper electrode or the lower electrode in plan view and is electrically independent from the upper electrode and the lower electrode. And disposed so as to surround the internal space and the upper electrode and the lower electrode, electrically independent from the upper electrode, the lower electrode, and the shield layer, and electrically connected to at least one of the electrode conductor layers Since it includes a shield conductor and a connecting portion for electrically connecting the shield layer and the electrode conductor layer, disposed in a region other than the flexible region on the surface of the insulating base, it may be a diaphragm. Since the shield layer formed on the outer surface of the flexible region and the electrode conductor layer are not electrically connected, when the plating layer is deposited on the exposed surface of the electrode conductor layer by the electrolytic plating method, Shield layer exposure The deposition of the plating layer on the surface can be suppressed that. Further, after the plating layer is deposited on the electrode conductor layer, the shield layer and the electrode conductor layer can be electrically connected at the connection portion. As a result, when the diaphragm is repeatedly bent due to external pressure fluctuations, it is possible to suppress the change rate of the capacitance value with respect to the pressure fluctuations. Since it is possible to satisfactorily suppress the influence of noise caused by electronic components, electronic devices and the like mounted on the periphery, it is possible to provide a pressure detecting base body capable of accurately detecting external pressure.

  Moreover, according to the base for a pressure detection device of the present invention, it is disposed on the outer surface of the flexible region so as to cover the upper electrode or the lower electrode in plan view, and is electrically independent from the upper electrode and the lower electrode. A shield layer, a shield conductor disposed so as to surround the internal space and the upper and lower electrodes, electrically independent of the upper electrode and the lower electrode, and electrically connected to the shield layer; and an insulating substrate Since it includes a shield layer disposed in a region other than the flexible region on the surface and a connection portion for electrically connecting the electrode conductor layer, the shield layer is formed on the outer surface of the flexible region that is a diaphragm. Since the shield layer and the electrode conductor layer are not electrically connected, when the plating layer is applied to the exposed surface of the electrode conductor layer by the electrolytic plating method, the shield layer is exposed to the exposed surface of the shield layer. Suppresses plating layer deposition Rukoto can. Further, after the plating layer is deposited on the electrode conductor layer, the shield layer and the shield conductor can be electrically connected to the electrode conductor layer at the connection portion. As a result, when the diaphragm is repeatedly bent due to external pressure fluctuations, it is possible to suppress the change rate of the capacitance value with respect to the pressure fluctuations. Since it is possible to satisfactorily suppress the influence of noise caused by electronic components, electronic devices and the like mounted on the periphery, it is possible to provide a pressure detecting base body capable of accurately detecting external pressure.

  Further, according to the pressure detecting device substrate of the present invention, in each of the above configurations, when the connecting conductor in which the connecting portion is electrically connected to the electrode conductor layer is disposed close to the shield layer, After the plating layer is deposited on the conductor layer, the shield layer and the electrode conductor layer are easily electrically connected by connecting the connecting conductor and the shield layer with a conductive connecting member such as a conductive adhesive. be able to.

  Further, according to the pressure detection device substrate of the present invention, in each of the above configurations, when the shield layer and the electrode conductor layer are electrically connected to each other through the conductive connection member in the connection portion, the shield layer and Since the shield conductor can satisfactorily suppress the influence of noise caused by electronic components, electronic equipment, etc. mounted around the pressure detection device, the pressure detection base body capable of accurately detecting external pressure and Become.

  According to the pressure detection device of the present invention, the electronic component is electrically connected to the electrode conductor layer of the pressure detection device base body of the present invention configured as described above. It is possible to accurately detect the external pressure by converting the change in electric capacity into the change in the external pressure value.

(A) is a top view which shows an example of embodiment of the base | substrate for pressure detection apparatuses of this invention, (b) is sectional drawing in the AA of (a). (A) is sectional drawing which shows the other example of the cross section in the AA of FIG. 1 (a), (b) is a top view which sees through and shows the inside of (a). (A) is a top view which shows the other example of embodiment of the base | substrate for pressure detection apparatuses of this invention, (b) is sectional drawing in the AA of (a). (A) is a top view which shows the other example of embodiment of the base | substrate for pressure detection apparatuses of this invention, (b) is sectional drawing in the AA of (a). It is sectional drawing which shows the other example of embodiment of the base | substrate for pressure detection apparatuses of this invention. It is sectional drawing which shows an example of embodiment of the pressure detection apparatus of this invention.

  The substrate for a pressure detection device and the pressure detection device of the present invention will be described with reference to the accompanying drawings. FIG. 1A is a top view showing an example of an embodiment of a pressure detecting device substrate of the present invention, and FIG. 1B is a cross-sectional view taken along line AA of FIG. 2A is a cross-sectional view showing another example of the cross section taken along the line AA of FIG. 1A, and FIG. 2B is a top view showing the inside of FIG. is there. 3 and 4 are top views showing another example of the embodiment of the pressure detecting device substrate of the present invention, respectively, and (b) is a cross-sectional view taken along the line AA of (a). It is. FIG. 5 is a cross-sectional view showing another example of the embodiment of the pressure detecting device substrate of the present invention. FIG. 6 is a cross-sectional view showing an example of an embodiment of the pressure detection device of the present invention. In these drawings, 1 is an insulating substrate, 1a is an internal space, 1b is an insulating substrate, 1c is a spacer, 1d is a diaphragm, 1e is a flexible region, 1f is an internal wiring, 1g is a frame, 1h is a hole, 2 Is an electrode conductor layer, 3 is an upper electrode, 4 is a lower electrode, 5 is a shield layer, 6 is a shield conductor, 6a is a shield auxiliary conductor, 7 is a connection portion, 7a is a connection conductor, 7b is a dam, and 8 is conductive. The conductive connecting member, 9 is an electronic component, 10 is a conductive bonding material, and 11 is a sealing resin.

  The substrate for a pressure detection device of the present invention has an internal space 1a having an upper surface and a lower surface facing each other as in the examples shown in FIGS. 1 to 3 and 5, and a plurality of electrode conductor layers 2 are formed on the surface. And an upper electrode 3 and a lower electrode 4 provided on the upper surface and the lower surface of the internal space 1a and facing each other. At least one of the upper surface and the lower surface is externally pressurized. Is a base for a pressure detection device having a flexible region 1e that is bent by the application of a pressure, and is arranged on the outer surface of the flexible region 1e so as to cover the upper electrode 3 or the lower electrode 4 in a plan view. 3 and the lower electrode 4, and the shield layer 5 that is electrically independent from the inner space 1 a and the upper electrode 3 and the lower electrode 4. The upper electrode 3, the lower electrode 4, and the shield layer 5 are Electrically And a shield conductor 6 electrically connected to at least one of the electrode conductor layers 2 and a shield layer 5 and an electrode conductor layer formed in a region other than the flexible region 1e on the surface of the insulating base 1. 2 and a connecting portion 7 for electrically connecting the two.

  Further, another example of the pressure detecting device substrate of the present invention has an internal space 1a having an upper surface and a lower surface facing each other as shown in FIG. 4, and a plurality of electrode conductor layers 2 are provided on the surface. And an upper electrode 3 and a lower electrode 4 provided on the upper surface and the lower surface of the internal space 1a and facing each other. At least one of the upper surface and the lower surface is externally pressurized. Is a base for a pressure detection device having a flexible region 1e that is bent by the application of a pressure, and is arranged on the outer surface of the flexible region 1e so as to cover the upper electrode 3 or the lower electrode 4 in a plan view. 3 and the lower electrode 4 are arranged so as to surround the inner space 1a and the upper electrode 3 and the lower electrode 4, and are electrically independent of the upper electrode 3 and the lower electrode 4. And shield layer 5 A shield conductor 6 that is electrically connected; and a connecting portion 7 for electrically connecting the shield layer 5 and the electrode conductor layer 2 disposed in a region other than the flexible region 1e on the surface of the insulating substrate 1; It has.

  According to such a pressure detecting device substrate of the present invention, the shield layer 5 and the electrode conductor layer 2 formed on the outer surface of the flexible region 1e which is the diaphragm 1d are not electrically connected. When the plating layer is deposited on the exposed surface of the electrode conductor layer 2 by the electrolytic plating method, the deposition of the plating layer on the exposed surface of the shield layer 5 can be suppressed. Further, after the plating layer is deposited on the electrode conductor layer 2, the shield layer 5 and the electrode conductor layer 2 can be electrically connected at the connection portion 7. Thereby, when the diaphragm 1f is repeatedly bent due to an external pressure fluctuation, it is possible to suppress the change rate of the capacitance value with respect to the pressure fluctuation, and the shield layer 5 and the shield conductor 6 can suppress the change. Since it is possible to satisfactorily suppress the influence of noise caused by electronic components, electronic devices, and the like mounted around the pressure detection device, a pressure detection device base body capable of accurately detecting external pressure is provided. it can.

  The insulating substrate 1 is an electrically insulating sintered body 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, as shown in the example shown in FIG. 1, the insulating substrate 1b, the frame-like spacer 1c, and the diaphragm 1d whose central portion is the flexible region 1e are formed, and these are laminated in order to form an internal space. 1a is formed.

  If the insulating base 1 is made of, for example, an aluminum oxide sintered body, it is manufactured as follows. First, a ceramic raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide is mixed with a suitable organic binder, solvent, plasticizer, and dispersant to form a slurry, and this is formed into a sheet by the doctor blade method. To obtain a plurality of ceramic green sheets. These ceramic green sheets are appropriately punched and cut to obtain ceramic green sheets for the insulating substrate 1 (for the insulating substrate 1b, for the spacer 1c, and for the diaphragm 1d). At this time, the ceramic green sheet for the spacer 1c is formed with a through hole serving as the internal space 1a by a punching method such as a die or punching or a hole processing method such as laser processing. By laminating these ceramic green sheets, a ceramic green sheet laminate for the insulating substrate 1 having the internal space 1a is formed. Then, by firing this ceramic green sheet laminate at a temperature of about 1600 ° C., the insulating substrate 1 having the internal space 1a is manufactured.

  As shown in the example shown in FIG. 5, for example, the insulating base 1 may be formed with a concave portion that accommodates the electronic component 9. In this case, the insulating substrate 1 functions as a container for housing the electronic component 9 and protecting the electronic component 9.

  In addition, the insulating substrate 1 may include a frame 1g on the outer peripheral portion of the diaphragm 1d as in the example shown in FIGS. The frame body 1g has the same shape as the spacer 1c, which is laminated in a region outside the flexible region 1e on the upper surface of the diaphragm 1d. Thus, when the ceramic green sheet laminate for the insulating substrate 1 is formed, the ceramic green sheet for the diaphragm 1d is sandwiched between the ceramic green sheet for the spacer 1c and the ceramic green sheet for the frame 1g from above and below. Therefore, warpage during firing can be suppressed. Since the frame 1g protrudes from the outer surface of the flexible region 1e, the ceramic green sheet laminate for the insulating substrate 1 before firing, the substrate for pressure detection device after firing, and the flexible region 1e of the pressure detection device. It is possible to reduce the possibility that the thin flexible region 1e will be damaged.

  The electrode conductor layer 2 on the surface of the insulating base 1 is for transmitting a change in capacitance between the upper electrode 3 and the lower electrode 4 to the external circuit board. The electrode 3 and the lower electrode 4 are connected to each other by an internal wiring 1 f formed inside the insulating base 1. Further, as in the example shown in FIG. 5, when the electronic component 9 is mounted on the pressure detection device, an electrode conductor layer 2 that functions as an electrode to which the terminal of the electronic component 9 is connected is also provided. Such an electrode conductor layer 2 is provided on the surface of the insulating substrate 1 other than the flexible region 1e. In the example shown in FIGS. 1 to 4, it is provided on the lower surface of the insulating substrate 1, but it may be provided on the side surface of the insulating substrate 1. Alternatively, as in the example shown in FIG. 5, a recess may be formed on the side surface of the insulating base 1 and provided on the inner surface of the recess to form a so-called castellation conductor.

  The lower electrode 4 is deposited on the lower surface (the upper surface of the insulating substrate 1b) of the internal space 1a of the insulating base 1, and the lower electrode 4 and the upper surface of the internal space 1a (the lower surface of the diaphragm 1d) of the insulating base 1 are attached. The upper electrode 3 is deposited so as to face each other. The lower electrode 4 and the upper electrode 3 are electrodes for forming a capacitance. Between these, an area where the lower electrode 4 and the upper electrode 3 face each other and an interval between the lower electrode 4 and the upper electrode 3 are set. A corresponding capacitance is formed. When pressure is applied to the insulating substrate 1 from the outside, the flexible region 1e of the diaphragm 1d bends toward the insulating substrate 1b in accordance with the pressure, and the distance between the lower electrode 4 and the upper electrode 3 changes, and the lower electrode Since the electrostatic capacitance between 4 and the upper electrode 3 changes, it functions as a pressure detection device that senses a change in external pressure as a change in electrostatic capacitance. By transmitting this change in capacitance to the external circuit board via the electrode conductor layer 2 and performing arithmetic processing with an electronic component mounted on the external circuit board, the magnitude of the external pressure can be known. When a recess is formed in the insulating base 1 and the electronic component 9 is mounted in the recess as in the example shown in FIG. 6, the change in capacitance is transmitted to the electronic component 9 without passing through the external circuit board. Is done.

  The electrode conductor layer 2, the upper electrode 3, the lower electrode 4, and the internal wiring 1 f are made of metal powder metallization such as tungsten, molybdenum, copper, or silver. For example, when the insulating substrate 1 is made of an aluminum oxide sintered body If so, a metallized paste obtained by adding and mixing a suitable organic binder, solvent, plasticizer, dispersant, etc. to a metal powder such as tungsten is formed into a predetermined pattern on a ceramic green sheet for the insulating substrate 1 by screen printing. A predetermined pattern is formed inside and on the surface of the insulating substrate 1 by printing and applying it and firing together with the ceramic green sheet laminate for the insulating substrate 1. The internal wiring 1f extending vertically in the insulating substrate 1 is formed by forming a through hole in the ceramic green sheet and filling the through hole with a metallized paste.

  The spacer 1c functions as providing a predetermined gap between the insulating substrate 1b having the lower electrode 4 on the upper surface and the diaphragm 1d having the upper electrode 3 on the lower surface, and has a through hole that forms the internal space 1a. It is formed in a plate shape (frame shape). When the spacer 1c has a thickness of less than 0.01 mm, the distance between the lower electrode 4 and the upper electrode 3 is small, and the flexible range of the flexible region 1e is small. It cannot be detected. On the other hand, if the distance exceeds 5 mm, the distance between the lower electrode 4 and the upper electrode 3 becomes large with respect to the amount of bending of the flexible region 1e, so that the rate of change in the distance between the electrodes becomes small and the capacitance is reduced. The rate of change becomes small and the sensitivity becomes low. Therefore, the thickness of the spacer 1c is preferably in the range of 0.01 mm to 5 mm.

  The diaphragm 1d bends toward the insulating substrate 1b according to the external pressure and functions as a pressure detecting diaphragm. In the example shown in FIG. 1, a portion corresponding to the upper surface of the inner space 1a of the diaphragm 1d, that is, a region overlapping with the through hole of the spacer 1c is a flexible region 1e, and the flexible region 1e is bent by applying pressure from the outside. It will be. In addition, if the thickness of the diaphragm 1d is less than 0.01 mm, its mechanical strength becomes small, and it becomes difficult to produce it using the above-described ceramic green sheet. On the other hand, when it exceeds 1 mm, it becomes difficult to bend with a small pressure, and it becomes unsuitable as a diaphragm for a pressure detection device. Therefore, the thickness of the diaphragm 1d is preferably in the range of 0.01 to 1 mm. The pressure detection device using the pressure detection substrate having the diaphragm 1d having such a thickness can be used under a pressure of 80 kPa (low pressure detection device) to 2000 kPa (high pressure detection device). is there.

  The internal space 1a is preferably a circular cylindrical shape in plan view. When the internal space 1a is circular, that is, the through-hole of the spacer 1c and the flexible region 1e of the diaphragm 1d are circular, the flexible region 1e of the diaphragm 1d is bent evenly when external pressure is applied. In addition, since a part of the thin diaphragm 1d is not greatly deformed, it is not broken from the diaphragm 1d, and the external pressure can be detected with high sensitivity.

  The upper electrode 3 and the lower electrode 4 formed on the diaphragm 1d are preferably circular in plan view. The flexible region 1e of the diaphragm 1d can be bent evenly.

  Moreover, it is preferable that at least one of the upper electrode 3 and the lower electrode 4 is smaller than the upper surface or the lower surface where the internal space 1a is provided. The rate of change of the interelectrode distance between the upper electrode 3 and the lower electrode 4 due to fluctuations in external pressure is large at the center side in the planar direction of the internal space 1a and small at the outer peripheral side of the internal space 1a. Therefore, if at least one of the upper electrode 3 and the lower electrode 4 is smaller than the upper surface or the lower surface where the internal space 1a is provided, only at the central portion of the internal space 1a where the change rate of the interelectrode distance is large. Since the upper electrode 3 and the lower electrode 4 can be made to face each other, the rate of change of the capacitance formed by the upper electrode 3 and the lower electrode 4 due to the application of external pressure increases, and the pressure detection device Can increase the sensitivity.

  Assuming that one of the upper electrode 3 and the lower electrode 4 is larger than the other, the upper electrode 3 and the lower electrode 4 are positioned even when there is a positional shift between the upper electrode 3 and the lower electrode 4 when the insulating substrate 1 is manufactured. This is preferable because the area facing the side electrode 4 does not change. Further, in this case, if the electrode formed on the diaphragm 1d, that is, the upper electrode 3 in the example shown in FIG. 1 is made larger than the upper surface of the internal space 1a as shown in the example shown in FIG. 1d can be flexed well, which is preferable. For example, if the upper electrode 3 smaller than the flexible region 1e of the diaphragm 1d is formed, there is a difference in deflection between the region where the upper electrode 3 is formed and the region where the upper electrode 3 is not formed in the flexible region 1e. This is because, if this difference is large, it may break at the boundary between these regions.

  The upper electrode 3 or the lower electrode 4 may be covered with an insulating layer made of a sintered body on at least one of the surfaces facing each other. For example, in the example shown in FIG. 5, the lower electrode 4 is covered with an insulating layer and embedded in the insulating substrate 1. Thereby, it can suppress that the diaphragm 1d bends with a big pressure, and the upper electrode 3 and the lower electrode 4 contact, and short-circuit.

  If the lower electrode 4 is smaller than the lower surface of the internal space 1a, the insulating layer may cover only the surface of the lower electrode 4, or the lower electrode 4 as in the example shown in FIG. 4 and the entire lower surface of the surrounding internal space 1a may be covered.

  It is preferable to use the same insulating layer as that of the insulating substrate 1 because it can be formed by simultaneous firing.

  Such an insulating layer is printed by applying a ceramic paste for the insulating layer on the metallized paste for the lower electrode 4 printed on the ceramic green sheet for the insulating substrate 1b by a printing means such as a screen printing method. Then, it can be formed by simultaneous firing with the ceramic green sheet laminate for the insulating substrate 1. The ceramic paste for the insulation layer is manufactured by mixing and kneading the ceramic powder of the main component with kneading means such as ball mill, three-roll mill, planetary mixer, etc., adding organic binder, organic solvent, dispersant if necessary Is done. Alternatively, it can be formed by laminating a ceramic green sheet for an insulating layer on a ceramic green sheet on which a metallized paste for the lower electrode 4 is printed. In addition, when forming an insulating layer with a ceramic green sheet, since the thickness dispersion | variation of an insulating layer can be reduced compared with the case where it forms by printing a ceramic paste, it is between the upper electrode 3 and the lower electrode 4. It can be set as the base | substrate for pressure detectors with a small dispersion | variation in a dielectric constant.

  The shield layer 5 is arranged on the outer surface of the flexible region 1e so as to cover the upper electrode 3 or the lower electrode 4 in a plan view, as in the example shown in FIGS. It is electrically independent from the electrode 4. Moreover, since the shield layer 5 and the electrode conductor layer 2 are not electrically connected, when the plating layer is deposited on the exposed surface of the electrode conductor layer 2 by electrolytic plating, the shield layer 5 It is possible to suppress the deposition of the plating layer on the exposed surface. Then, after the plating layer is deposited on the electrode conductor layer 2, the electrode conductor layer 2 is electrically connected to the ground potential.

  The shield conductor 6 is disposed so as to surround the internal space 1 a and the upper electrode 3 and the lower electrode 4, and is electrically independent from the upper electrode 3 and the lower electrode 4. In the example shown in FIG. 1 to FIG. 3 and FIG. 5, the shield layer 5 is electrically independent and electrically connected to the electrode conductor layer 2 having a ground potential. The example shown in FIG. 5 and is electrically connected to the electrode conductor layer 2 that is at the ground potential after the plating layer is deposited on the electrode conductor layer 2. Such a shield conductor 6 may be formed of a plurality of through conductors penetrating the insulating base 1 around the internal space 1a, as in the examples shown in FIGS. 1, 2, 4 and 5. As in the example shown in FIG. 3, the insulating base 1 may be formed of a side conductor on the side surface. In order to obtain a smaller pressure detection substrate, it is better to form a plurality of through conductors inside the insulating substrate 1, and it is easier to form than the side surface.

  When the shield conductor 6 is formed of a plurality of through conductors, it is preferable that the distance between the through conductors be as small as possible because it is excellent in noise shielding properties. However, 0.2 mm so that cracks do not occur between the through conductors in the manufacturing process. It is preferable to provide a certain interval. In the example shown in FIGS. 1, 2, 4, and 5, the through conductors of the shield conductor 6 surround the inner space and the through conductors are arranged in a ring shape. It may be. At this time, by arranging the through conductors of the outer array between the through conductors of the inner array in a side view, noise can be more effectively shielded by reducing the gap between the through conductors on the side surface. Therefore, it is preferable. As in the examples shown in FIGS. 2, 4 and 5, it is preferable that they are arranged at equal intervals because there is no portion where stress is concentrated and breaks easily due to the small interval.

  2 and 3, when the shield conductor 6 is formed of a plurality of through conductors, an area where the distance between the outer peripheral edge of the internal space 1a and the outer peripheral edge of the insulating base 1 is the smallest is avoided. It is preferable to provide them. Thereby, when manufacturing the base body for pressure detectors, it can suppress that the crack etc. generate | occur | produce around the shield conductor 6, and it can suppress that the airtightness of the internal space 1a falls, and the small size excellent in reliability. It becomes easy to produce a base for a pressure detection device. In the example shown in FIG. 2, one of the shield conductors 6, the connection conductor 7 a of the connection portion 7, and the through conductor of the internal wiring 1 f that connects the electrode conductor layer 2 are formed at close positions. When the distance between the two is extremely close and a crack or the like is likely to occur between them, the through conductor of the internal wiring 1f may also serve as the shield conductor 6 as in the example shown in FIG. In order to prevent similar cracks and the like, the distance between the internal wiring 1f extending vertically in the insulating substrate 1 and the shield conductor 6 formed of a through conductor is also reduced as in the examples shown in FIGS. It is preferable to arrange so as to be large.

  The shield conductor 6 is electrically connected to the electrode conductor layer 2 having a ground potential. When the shield conductor 6 is a through conductor, a plurality of shield conductors 6 are provided as shown in FIG. It may be connected to the electrode conductor layer 2 via the internal wiring 1f connected to each of them, and arranged so as to surround the upper electrode 3, the lower electrode 4, and the internal space 1a as shown in the example of FIG. The auxiliary shield conductor 6a that electrically connects the plurality of shield conductors 6 may be formed, and the auxiliary shield conductor 6a may be connected to the electrode conductor layer 2 via the internal wiring 1f. When the auxiliary shield conductor 6a is provided, the area of the shield conductor 6 is increased and the noise shielding performance is improved, so that the influence of noise can be further reduced. When the insulating base 1 such as the spacer 1c is formed of a plurality of insulating layers, the influence of noise can be more effectively suppressed by providing the auxiliary shield conductors 6a between the plurality of insulating layers. Further, as shown in the example of FIG. 2, the auxiliary shield conductor 6a is more preferably shaped (annular) so as to connect all the shield conductors 6 and surround the inner space 1a and the like over the entire circumference.

  When the shield conductor 6 is a side conductor, it may be an integrated side conductor formed over the entire circumference of the side surface as shown in FIG. 3A, or a plurality of side conductors may be arranged. It may be what you did. In the case of being integrally formed over the entire circumference, the shielding effect is higher, and it is only necessary to provide one internal wiring 1 f for connecting to the electrode conductor layer 2. In the case where a plurality of side conductors are arranged, the formation becomes easy.

  Such a shield layer 5, shield conductor 6, and auxiliary shield conductor 6a are formed by the same material and manufacturing method as those for forming the internal wiring 1f, the electrode conductor layer 2, the upper electrode 3, and the lower electrode 4 described above. can do. The shield layer 5 is formed by printing and applying a metallized paste for the shield layer 5 to a region to be the outer main surface of the flexible region 1e of the ceramic green sheet for the diaphragm 1d by screen printing. Further, when the shield conductor 6 is a through conductor, the through hole is formed so as to surround the regions to be the internal space 1a, the upper electrode 3 and the lower electrode 4 of the ceramic green sheet for the insulating substrate 1b, the spacer 1c, and the diaphragm 1d. This is formed by filling the through hole with a metallized paste for the shield conductor 6. When the shield conductor 6 is a side conductor, it may be formed by applying a metallized paste for the shield conductor 6 on the side surface of the ceramic green sheet laminate, or the outer side of the insulating base 1 of the ceramic green sheet. A through hole having a shape along the outer side or a plurality of through holes along the outer side, and filling the through hole with metallized paste for the shield conductor 6 or applying to the inner surface of the through hole And you may form by dividing | segmenting a through-hole and cut | disconnecting a ceramic green sheet laminated body. Particularly when a small-sized pressure sensing device base is produced in the form of a so-called multi-piece substrate, the side conductor shield layer 6 can be formed efficiently by this method. You may form by apply | coating the metallizing paste for the shield conductor 6 to the side surface of the insulated base 1 after baking, and baking. The auxiliary shield conductor 6a is formed by printing and applying metallized paste for the auxiliary shield conductor 6a on a predetermined position of the ceramic green sheet for the insulating substrate 1b, the spacer 1c, and the diaphragm 1d by screen printing. In addition, since the portion where the ceramic green sheets are closely adhered to each other is hardly peeled off, in order to improve the airtightness of the internal space 1a, for example, when the auxiliary shield conductor 6a is annular, It is preferable to form the ring-shaped spacer having a smaller width than the width of the frame-shaped spacer 1c.

  As shown in the examples of FIGS. 1 to 5, the connecting portion 7 for electrically connecting the shield layer 5 and the electrode conductor layer 2 to a region other than the flexible region 1 e on the surface of the insulating base 1. Is formed. The connection portion 7 is for electrically connecting the shield layer 5 and the electrode conductor layer 2 after depositing the plating layer on the exposed surface of the electrode conductor layer 2 by electrolytic plating. . By disposing the connection portion 7 on the surface of the insulating substrate 1, the shield layer 5 and the electrode conductor layer 2 after the plating layer is deposited can be easily connected. Further, if the position where the connecting portion 7 is disposed is an area other than the flexible area 1e on the surface of the insulating base 1, it does not affect the bending of the flexible area 1e due to pressure fluctuations. Other than the surroundings, the insulating substrate 1 may be disposed on the side surface or the lower surface, or in the recess if the insulating substrate 1 has a recess as in the example shown in FIG.

  Moreover, it is preferable that the connection part 7 is arrange | positioned in the proximity of the shield layer 5 as the connection part 7 is electrically connected to the conductor layer 2 for electrodes like the example shown in FIGS. Since the connection conductor 7a is disposed close to the shield layer 5, the connection conductor 7a and the shield layer 5 can be easily connected by the conductive connection member 8 such as a conductive adhesive. Electrical connection between the shield layer 5 and the electrode conductor layer 2 is facilitated. At this time, it is good also as a shape which has the part which protruded the shield layer 5 toward the connection conductor 7a like the example shown in FIG. 3 and FIG. By doing so, the through conductor of the internal wiring 1f connected to the connection conductor 7a can be separated from the shield conductor 6 and the internal space 1a. Therefore, the through conductor of the internal wiring 1f and the through conductor of the shield conductor 6 and the internal Cracks and the like are less likely to occur between the space 1a. If the connection conductor 7a is disposed in the side surface, the lower surface, or the concave portion of the lower surface of the insulating substrate 1 away from the shield layer 5, the connection by the conductive connection member 8 such as a conductive adhesive becomes difficult. Alternatively, in order to facilitate the connection by the conductive connection member 8 such as a conductive adhesive, the wiring has to be routed from the shield layer 5 to the vicinity of the connection conductor 7a. Instead of forming the connection conductor 7a as in the example shown in FIGS. 1 to 5 on the surface of the insulating base 1, the portion where the internal wiring 1f is exposed on the surface of the insulating base 1 may be used as the connection conductor 7a.

  As shown in the examples of FIGS. 2 and 4, the connecting portion 7 may be disposed in the hole 1h formed in the frame 1g if the insulating base 1 is provided with the frame 1g. Absent. As a result, since the conductive connecting member 8 does not spread unintentionally, it can be reliably connected at the joint 7, and the conductive connecting member 8 flows out onto the flexible region 1 e to bend the diaphragm 1 d. It is possible to suppress the influence on When the frame body 1g is not provided, a similar effect can be obtained by providing an annular dam 7b in the connecting portion 7 as in the example shown in FIG.

  The connecting conductor 7a of the connecting portion 7 can be formed by the same material and manufacturing method as those for forming the electrode conductor layer 2, the upper electrode 3, the lower electrode 4, and the internal wiring 1f. The connection conductor layer 7 is formed by applying a metallized paste for the connection conductor 7a on the outside of the portion where the shield layer 5 of the ceramic green sheet for the diaphragm 1d is formed by a screen printing method, so that the ceramic green sheet for the insulating substrate 1 is applied. By baking together with the laminated body, it is formed on the outer main surface of the flexible region 1e. When the metallized paste for the shield layer 5 is printed and applied, it may be formed by simultaneously printing and applying the same metalized paste.

  Further, in the base for a pressure detection device of the present invention, as shown in the example shown in FIG. 5, the shield layer 5 and the electrode conductor layer 2 are electrically connected to each other via the conductive connection member 8 at the connection portion 7. It is characterized by being. Since the shield layer 5 and the shield conductor 6 can satisfactorily suppress the influence of noise caused by electronic components, electronic devices and the like mounted around the pressure detection device, the external pressure can be detected with high accuracy. It becomes a base for pressure detection.

  In addition, before electrically connecting the shield layer 5 and the electrode conductor layer 2 with the conductive connection member 8, the exposed surface of the electrode conductor layer 2 is prevented from being oxidized and corroded. In addition, in order to improve the bonding between the electrode conductor layer 2 and the conductive bonding material 10 such as solder and the wiring conductor of the external circuit board, A gold plating layer having a thickness of about 0.1 to 3 μm is sequentially deposited by an electrolytic plating method.

  If the conductive connection member 8 is a conductive resin in which silver powder is dispersed in an epoxy resin, for example, it can be easily connected. Further, a metal plate material or the like may be joined to the shield layer 5 and the connection portion 7 to electrically connect the shield layer 5 and the electrode conductor layer 2.

  As shown in the example shown in FIG. 6, the pressure detection device of the present invention is characterized in that an electronic component 9 is electrically connected to the electrode conductor layer 2 of the pressure detection device base body of the present invention having the above-described configuration. To do. According to the pressure detection device of the present invention, a change in electrostatic capacitance formed between the lower electrode 4 and the upper electrode 3 is transmitted to the electronic component 9 via the internal wiring 1f and the electrode conductor layer 2. By calculating this with the electronic component 9, it is possible to know the change in the external pressure value. When the electronic component 9 is directly connected to the electrode conductor layer 2 through the conductive bonding material 10 as in the example shown in FIG. 6, the electronic component 9 is connected to the electronic component 9 mounted on the external circuit board. On the other hand, since the wiring length between the lower electrode 4 and the upper electrode 3 and the electronic component 9 can be shortened, the external pressure can be detected with high accuracy. In addition, the pressure sensor module including the pressure detection device and the external circuit board can be reduced in size by using the pressure detection device in which the electronic component 9 is incorporated.

  In the example shown in FIG. 6, the electronic component 9 is a semiconductor element for performing the above-described arithmetic processing, but in addition to this, a passive element such as a chip capacitor or a chip resistor, or an electronic component 9 such as an acceleration sensor is mounted. It doesn't matter.

  Further, in the example shown in FIG. 6, the flip chip type electronic component 9 is bonded to the electrode conductor layer 2 in the recess through the conductive bonding material 10. Thereby, each electrode of the electronic component 9 and each electrode conductor layer 2 are electrically connected, and the electronic component 9 is fixed to the insulating base 1. Examples of the conductive bonding material 10 in this case include solder bumps, gold bumps, or conductive resins (such as anisotropic conductive resins). Further, when the electronic component 9 is of the wire bonding type, after being fixed with a bonding material such as glass, resin, brazing material, etc., the electrode of the electronic component 9 and the electrode conductor layer 2 are bonded via the bonding wire. This is done by electrical connection.

  In the example shown in FIG. 6, the electronic component 9 is sealed by being covered with a sealing resin 11 such as an epoxy resin. Alternatively, a lid made of metal or ceramic is joined to the insulating base 1 so as to cover the recessed portion in the case of the insulating base 1 shown in FIG. 5 so as to cover the mounted electronic component 9. May be sealed.

  The base for the pressure detecting device of the present invention can be variously modified within a range not departing from the gist of the present invention. For example, a shield layer that covers the lower electrode 4 may be formed inside or on the lower surface of the insulating substrate 1b. In this case, since this is not the outer surface of the flexible region 1e, this shield layer may be electrically connected to the electrode conductor layer 2. The flexible region 1e is provided only on the upper surface of the internal space 1a. However, the flexible region 1e may have the flexible region 1e on the lower surface of the internal space 1a, or both on the upper surface and the lower surface of the internal space 1a. It may have a flexible region 1e. In either case, the shield layer 5 may be formed on the outer surface of the flexible region 1e. Further, a combination of the above examples may be used. For example, when the shield conductor 6 is formed of a plurality of through conductors, the shield conductor 6 electrically connected to the shield layer 5 is not electrically connected to the shield conductor 5 and the electrode conductor layer 2 is electrically connected. The shield conductor 6 may be connected to the other. In this case, the shield conductor 6 electrically connected to the shield layer 5 is applied to the electrode via the conductive connection member 8 at the connection portion 7 after the plating layer is deposited on the exposed surface of the electrode conductor layer 2. It is electrically connected to the conductor layer 2. Alternatively, the shield conductor 6 may be formed of both a plurality of through conductors and side conductors. Even if the through conductors and the side conductors are arranged at intervals, noise can be shielded more effectively.

DESCRIPTION OF SYMBOLS 1 ... Insulating base | substrate 1a ... Internal space 1b ... Insulating substrate 1c ... Spacer 1d ... Diaphragm 1e ... Flexible area 1f ... Internal wiring 1g ... Frame 1h ... -Hole 2 ... Electrode conductor layer 3 ... Upper electrode 4 ... Lower electrode 5 ... Shield layer 6 ... Shield conductor 6a ... Shield auxiliary conductor 7 ... Connection 7a ... Connection conductor 7b ... Dam 8 ... Conductive connection member 9 ... Electronic component 10 ... Conductive bonding material 11 ... Sealing resin

Claims (5)

An insulating base made of a sintered body having an inner space with an upper surface and a lower surface facing each other and having a plurality of electrode conductor layers on the surface, and an upper electrode and a lower electrode facing each other through the inner space A base for a pressure detection device having a flexible region that bends when pressure is applied from the outside to at least one of the upper surface and the lower surface,
A shield layer disposed on the outer surface of the flexible region so as to cover the upper electrode or the lower electrode in plan view, and electrically independent of the upper electrode and the lower electrode;
The inner space, the upper electrode, and the lower electrode are disposed so as to surround, and are electrically independent from the upper electrode, the lower electrode, and the shield layer, and are electrically connected to at least one of the electrode conductor layers. Connected shield conductors,
A pressure detecting device comprising: a connecting portion for electrically connecting the shield layer and the electrode conductor layer disposed in a region other than the flexible region on the surface of the insulating base. Substrate. An insulating base made of a sintered body having an inner space with an upper surface and a lower surface facing each other and having a plurality of electrode conductor layers on the surface, and an upper electrode and a lower electrode facing each other through the inner space A base for a pressure detection device having a flexible region that bends when pressure is applied from the outside to at least one of the upper surface and the lower surface,
A shield layer disposed on the outer surface of the flexible region so as to cover the upper electrode or the lower electrode in plan view, and electrically independent of the upper electrode and the lower electrode;
A shield conductor disposed so as to surround the internal space and the upper electrode and the lower electrode, electrically independent of the upper electrode and the lower electrode, and electrically connected to the shield layer;
A pressure detecting device comprising: a connecting portion for electrically connecting the shield layer and the electrode conductor layer disposed in a region other than the flexible region on the surface of the insulating base. Substrate.   3. The pressure detecting device according to claim 1, wherein the connection portion is configured such that a connection conductor electrically connected to the electrode conductor layer is disposed adjacent to the shield layer. 4. Substrate.   4. The pressure detection device according to claim 1, wherein the shield layer and the electrode conductor layer are electrically connected to each other through the conductive connection member in the connection portion. 5. Substrate.   An electronic component is electrically connected to the electrode conductor layer of the base for a pressure detection device according to claim 4.

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