Patent Publication Number: US-11659664-B2

Title: Electronic device

Description:
The present application is based on, and claims priority from JP Application Serial Number 2020-152562, filed Sep. 11, 2020, the disclosure of which is hereby incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to an electronic device. 
     2. Related Art 
     A piezoelectric device disclosed in JP-A-2007-173431 includes a substrate, a piezoelectric vibrator and a semiconductor chip mounted on an upper surface of the substrate, and a mold material for molding the piezoelectric vibrator and the semiconductor chip. The piezoelectric vibrator is bonded to the substrate via solder, and the solder serves as a spacer to form a minute gap between the substrate and the piezoelectric vibrator. 
     However, in the above-described configuration, since the gap between the substrate and the piezoelectric vibrator is minute, filling of the mold material into the gap is insufficient, and the gap may not be completely filled. As described above, when the piezoelectric device in which the gap between the substrate and the piezoelectric vibrator is not completely filled with the mold material is solder-mounted on an external substrate such as a motherboard, the solder bonding the piezoelectric vibrator and the substrate may be melted by the heat, and the melted solder may wet and spread in the gap to cause a short circuit. 
     SUMMARY 
     An electronic device according to the present disclosure includes: a substrate having a first surface and a second surface that are in a front and back relationship with each other, a first wiring pattern being disposed on the first surface, and a second wiring pattern being disposed on the second surface; a first electronic component mounted on the first surface of the substrate; a second electronic component mounted on the second surface of the substrate; and a mold portion that covers the second electronic component without covering the first electronic component, in which the first electronic component includes a first mounting terminal disposed on a first relative surface relative to the first surface, and is bonded to the first surface on the first relative surface via a conductive first bonding member, and the first mounting terminal and the first wiring pattern are electrically coupled to each other via the first bonding member, and the second electronic component includes a second mounting terminal, and is bonded to the second surface via a second bonding member on a second relative surface relative to the second surface, and the second mounting terminal and the second wiring pattern are electrically coupled to each other via a conductive wire. 
     An electronic device according to the present disclosure includes: a substrate having a first surface and a second surface that are in a front and back relationship with each other, a first wiring pattern being disposed on the first surface, and a second wiring pattern being disposed on the second surface; a first electronic component mounted on the first surface of the substrate; a second electronic component mounted on the second surface of the substrate; and a mold portion that covers the second electronic component without covering the first electronic component, in which the first electronic component includes a first mounting terminal disposed on a first relative surface relative to the first surface, and is bonded to the first surface on the first relative surface via a conductive first bonding member, and the first mounting terminal and the first wiring pattern are electrically coupled to each other via the first bonding member, and the second electronic component includes a second mounting terminal disposed on a second relative surface relative to the second surface, and is bonded to the second surface on the second relative surface via a conductive second bonding member having a melting point higher than that of the first bonding member, and the second mounting terminal and the second wiring pattern are electrically coupled to each other via the second bonding member. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view showing an electronic device according to a first embodiment. 
         FIG.  2    is a plan view showing inside of a cap of the electronic device shown in  FIG.  1   . 
         FIG.  3    is a cross-sectional view taken along a line A-A in  FIG.  2   . 
         FIG.  4    is a flowchart showing manufacturing steps of the electronic device shown in  FIG.  1   . 
         FIG.  5    is a plan view showing a lead frame. 
         FIG.  6    is a cross-sectional view for illustrating a method of manufacturing the electronic device. 
         FIG.  7    is a cross-sectional view for illustrating the method of manufacturing the electronic device. 
         FIG.  8    is a cross-sectional view for illustrating the method of manufacturing the electronic device. 
         FIG.  9    is a cross-sectional view for illustrating the method of manufacturing the electronic device. 
         FIG.  10    is a cross-sectional view for illustrating the method of manufacturing the electronic device. 
         FIG.  11    is a cross-sectional view showing an electronic device according to a second embodiment. 
         FIG.  12    is a cross-sectional view showing an electronic device according to a third embodiment. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, an electronic device according to an aspect of the present disclosure will be described in detail based on an embodiment illustrated in the accompanying drawings. For convenience of illustration, three axes orthogonal to one another are illustrated as an X axis, a Y axis, and a Z axis in each of the drawings except for  FIG.  4   . A direction parallel to the X axis is also referred to as an “X axis direction”. A direction parallel to the Y axis is also referred to as a “Y axis direction”. A direction parallel to the Z axis is also referred to as a “Z axis direction”. A tip end side of an arrow indicating each axis is also referred to as a “positive side”. An opposite side thereof is also referred to as a “negative side”. The positive side in the Z axis direction is also referred to as “upper”. The negative side in the Z axis direction is also referred to as “lower”. 
     First Embodiment 
       FIG.  1    is a perspective view showing an electronic device according to a first embodiment.  FIG.  2    is a plan view showing inside of a cap of the electronic device shown in  FIG.  1   .  FIG.  3    is a cross-sectional view taken along a line A-A in  FIG.  2   .  FIG.  4    is a flowchart showing manufacturing steps of the electronic device shown in  FIG.  1   .  FIG.  5    is a plan view showing a lead frame.  FIGS.  6  to  10    are cross-sectional views for illustrating a method of manufacturing the electronic device. In  FIG.  2   , a first wiring pattern is not shown for convenience of illustration. 
     An electronic device  1  shown in  FIG.  1    has a quad flat package (QFP) structure. As shown in  FIGS.  2  and  3   , the electronic device  1  includes a substrate  2 , a first electronic component  3  located on an upper surface  21  side of the substrate  2  and bonded to the upper surface  21 , a second electronic component  4  located on a lower surface  22  side of the substrate  2  and bonded to the lower surface  22 , a lead group  7  including a plurality of leads  71  bonded to the lower surface  22  of the substrate  2 , a cap  8  covering the substrate  2  so as to cover the first electronic component  3 , and a mold portion  9  that molds and seals the second electronic component  4  and bonds the cap  8  to the substrate  2 . The electronic device  1  includes three angular velocity sensors  3   x ,  3   y , and  3   z  as the first electronic component  3 , and includes an acceleration sensor  5  and a circuit element  6  as the second electronic component  4 . 
     The substrate  2  has a substantially square plate shape in a plan view, and has the upper surface  21  as a first surface and the lower surface  22  as a second surface which are in a front and back relationship with each other. The substrate is a ceramic substrate and is made of various ceramic materials such as alumina and titania. When the ceramic substrate is used as the substrate  2 , the substrate  2  has high corrosion resistance. The substrate  2  having excellent mechanical strength is obtained. Since moisture absorption is less likely to occur and heat resistance is excellent, damage due to heat applied at the time of manufacturing the electronic device  1  is less likely to occur. By using the same material as that of a base  32  included in the angular velocity sensors  3   x ,  3   y , and  3   z , thermal stress due to a linear expansion coefficient difference is less likely to occur therebetween. Therefore, the electronic device  1  having excellent long-term reliability is obtained. The substrate  2  is not limited to a ceramic substrate. For example, various semiconductor substrates, various glass substrates, and various printed substrates can also be used. 
     A first wiring pattern  28  electrically coupled to the first electronic component  3  is disposed on the upper surface  21  of the substrate  2 . On the other hand, a second wiring pattern  29  electrically coupled to the second electronic component  4  is disposed on the lower surface  22  of the substrate  2 . The first wiring pattern  28  is electrically coupled to the second wiring pattern  29  via a through electrode, which is not shown, formed in the substrate  2 . 
     The first electronic component  3  is a packaged surface mount component. Accordingly, it is possible to exhibit higher mechanical strength than a mount component in which an element is exposed. The first electronic component can be easily mounted on the substrate  2 . The first electronic component  3  is a physical quantity sensor. In particular, in the present embodiment, three angular velocity sensors  3   x ,  3   y , and  3   z  are provided. The angular velocity sensor  3   x  is a sensor that detects an angular velocity around the X axis. The angular velocity sensor  3   y  is a sensor that detects an angular velocity around the Y axis. The angular velocity sensor  3   z  is a sensor that detects an angular velocity around the Z axis. By using the first electronic component  3  as the physical quantity sensor, the electronic device  1  that is suitably mounted on various electronic devices and mobile bodies is obtained. Therefore, convenience and demand of the electronic device  1  are increased. In particular, since the electronic device  1  can detect the angular velocities about three axes orthogonal to one another, the above effect is more remarkable. 
     Basic configurations of the angular velocity sensors  3   x ,  3   y , and  3   z  are the same as one another. The angular velocity sensors  3   x ,  3   y , and  3   z  are mounted in different postures so that detection axes face the X-axis direction, the Y-axis direction, and the Z-axis direction. As shown in  FIG.  3   , each of the angular velocity sensors  3   x ,  3   y , and  3   z  includes a package  31  and a physical quantity detection element  34  accommodated in the package  31 . The package  31  includes a box-shaped base  32  having a recess  321 , and a lid  33  bonded to the base  32  so as to close an opening of the recess  321 . The base  32  is constituted by a ceramic material such as alumina. The lid  33  is constituted by a metal material such as Kovar. 
     As shown in  FIG.  3   , a plurality of first mounting terminals  39  electrically coupled to the physical quantity detection element  34  are disposed on a lower surface of the package  31 , that is, a first relative surface  320  relative to the upper surface  21  of the substrate  2 . The physical quantity detection element  34  is, for example, a crystal vibration element having a drive arm and a vibration arm. In such a crystal vibration element, when the angular velocity around the detection axis is applied in a state where a drive signal is applied to drive and vibrate the drive arm, detection vibration is excited in the detection arm by Coriolis force. Electric charge generated in the detection arm by the detection vibration is extracted as a detection signal. The angular velocity can be obtained based on the extracted detection signal. 
     Each of the angular velocity sensors  3   x ,  3   y , and  3   z  is bonded to the upper surface  21  of the substrate  2  via a conductive first bonding member B 1  on the first relative surface  320 . The first mounting terminal  39  of each of the angular velocity sensors  3   x ,  3   y , and  3   z  is electrically coupled to the first wiring pattern  28  via the first bonding member B 1 . The first bonding member B 1  is solder, and mechanically and electrically couples the angular velocity sensors  3   x ,  3   y , and  3   z  to the substrate  2  by solder reflow. Accordingly, it is possible to easily and accurately couple the angular velocity sensors  3   x ,  3   y , and  3   z  to the substrate  2 . The first bonding member B 1  is less deteriorated over time and has high reliability. The first bonding member B 1  is not limited to solder. For example, various brazing materials such as gold brazing filler and silver brazing filler, various metal bumps such as gold bumps and silver bumps, and various conductive adhesives in which a conductive filler is dispersed in a resin-based adhesive can be used. 
     Although the angular velocity sensors  3   x ,  3   y , and  3   z  are described above, the configurations of the angular velocity sensors  3   x ,  3   y , and  3   z  are not particularly limited. For example, the physical quantity detection element  34  may be formed of a capacitive silicon vibration element and detect the angular velocity based on a change in capacitance. At least one of the angular velocity sensors  3   x ,  3   y , and  3   z  may be different from the other angular velocity sensors. In the first electronic component  3 , at least one of the angular velocity sensors  3   x ,  3   y , and  3   z  may be omitted. The first electronic component  3  may be a physical quantity sensor that detects a physical quantity other than the angular velocity, or may not be a physical quantity sensor. The first electronic component  3  does not have to be a packaged surface mount component. For example, the package  31  may be omitted and the physical quantity detecting element  34  may be exposed in the cap  8 . 
     As shown in  FIG.  3   , the cap  8  is bonded to the substrate  2 , and accommodates the angular velocity sensors  3   x ,  3   y , and  3   z  between the cap  8  and the substrate  2 . The cap  8  has a hat shape, and includes a base portion  81  having a recess  811  that opens to the upper surface  21  side, and an annular flange portion  82  protruding from a lower end portion of the base portion  81  toward an outer peripheral side. The cap  8  is disposed on the upper surface  21  of the substrate  2  so as to accommodate the angular velocity sensors  3   x ,  3   y , and  3   z  in the recess  811 . The flange portion  82  is in contact with the upper surface  21 . Then, the cap  8  and the substrate  2  are bonded to each other by the mold portion  9 , and the inside of the recess  811  is hermetically sealed. 
     In this way, by providing the cap  8  that accommodates the angular velocity sensors  3   x ,  3   y , and  3   z , the angular velocity sensors  3   x ,  3   y , and  3   z  can be protected from moisture, dust, impact, and the like. In the present embodiment, the inside of the recess  811  is air-sealed. The present disclosure is not limited thereto. For example, sealing under reduced pressure or sealing under positive pressure may be performed, or the gas may be replaced with a stable gas such as nitrogen or argon. 
     The cap  8  has conductivity and is formed of, for example, a metal material. In particular, in the present embodiment, the cap  8  is formed of a 42 alloy which is an iron-nickel alloy. Accordingly, the linear expansion coefficient difference between the substrate  2  formed of the ceramic substrate and the cap  8  can be made sufficiently small. Generation of thermal stress due to the linear expansion coefficient difference can be effectively prevented. Therefore, the electronic device  1  is hardly affected by an environmental temperature and has stable characteristics. The cap  8  is coupled to aground (GND) when the electronic device  1  is used. Accordingly, the cap  8  functions as a shield that blocks electromagnetic noise from the outside. Driving of the angular velocity sensors  3   x ,  3   y , and  3   z  accommodated in the cap  8  is stabilized. A constituent material of the cap  8  is not limited to the 42 alloy. For example, a metal material such as a SUS material, various ceramic materials, various resin materials, a semiconductor material such as silicon, and various glass materials can also be used. 
     Here, as a method of bonding the cap  8  and the substrate  2 , there is a method of using an adhesive disposed between the flange portion  82  and the substrate  2 , particularly an adhesive containing an organic component such as a resin-based adhesive. However, in the present embodiment, such a method is not adopted, and the cap  8  and the substrate  2  are bonded by the mold portion  9 . Accordingly, it is possible to reduce a height of the electronic device  1  as compared with the method in which the adhesive is disposed between the flange portion  82  and the substrate  2 . There is no risk that the inside of the cap  8  may be contaminated by outgas containing the organic component generated from the adhesive. It is also possible to prevent a decrease in the reliability due to aged deterioration of the adhesive. Therefore, the electronic device  1  is small and has high reliability. Further, since no adhesive is used, the manufacturing cost of the electronic device  1  can be reduced. The method of bonding the cap  8  and the substrate  2  is not particularly limited. 
     In the electronic device  1 , the recess  811  is a gap and is not filled with the mold portion  9 . That is, the angular velocity sensors  3   x ,  3   y , and  3   z  accommodated in the cap  8  are not covered with the mold portion  9 . Therefore, the problem described in the related art, that is, the problem that the mold material cannot be fully filled in the gap formed between the angular velocity sensors  3   x ,  3   y , and  3   z  and the substrate  2  due to the thickness of the first joining member B 1 , and a minute gap is formed in the portion does not occur. Therefore, even if the first bonding member B 1  is melted by heat applied when the electronic device  1  solder-mounted on an external substrate, unlike the related art, wetting and spreading of the melted first bonding member B 1  to an unintended portion is prevented. Therefore, it is possible to prevent the occurrence of electrical defects such as a short circuit, a disconnection, and an increase in wiring resistance. 
     As shown in  FIGS.  2  and  3   , the second electronic component  4  includes the acceleration sensor  5  and the circuit element  6 . Since the electronic device  1  includes the circuit element  6 , the angular velocity sensors  3   x ,  3   y , and  3   z  and the acceleration sensor  5  can be coupled to the circuit element  6  in the electronic device  1 . Therefore, a wiring length for coupling the components can be shortened. Therefore, in particular, noise is less likely to be added to detection signals output from the angular velocity sensors  3   x ,  3   y , and  3   z  and the acceleration sensor  5 , and the angular velocity around each axis and the acceleration in each axis direction can be more accurately detected. 
     As shown in  FIG.  3   , the acceleration sensor  5  is bonded to the lower surface  22  via a second bonding member B 2  on an upper surface thereof, that is, a second relative surface  50  relative to the lower surface  22  of the substrate  2 . The circuit element  6  is bonded to the lower surface of the acceleration sensor  5  via a third bonding member B 3  on an upper surface thereof, that is, a third relative surface  60  relative to the lower surface of the acceleration sensor  5 . In the present embodiment, since a shape of the acceleration sensor  5  in the plan view is larger than a shape of the circuit element  6  in the plan view, the acceleration sensor  5  is bonded to the substrate  2 , and the circuit element  6  is bonded to the acceleration sensor  5 . Accordingly, the acceleration sensor  5  and the circuit element  6  can be disposed on the substrate  2  in a well-balanced manner. 
     Here, the second bonding member B 2  and the third bonding member B 3  are not electrically coupled. Therefore, as the second bonding member B 2  and the third bonding member B 3 , for example, various die attach agents, and various die attach films can be used regardless of whether the second bonding member B 2  and the third bonding member B 3  are conductive or not. 
     The acceleration sensor  5  is a three-axis acceleration sensor capable of independently detecting an acceleration in the X axis direction, an acceleration in the Y axis direction, and an acceleration in the Z axis direction. That is, the electronic device  1  is a six-axis composite sensor capable of detecting the angular velocity around each axis of the X axis, the Y axis, and the Z axis and the acceleration in each axis direction. In this way, by making the electronic device  1  usable as the physical quantity sensor, the electronic device  1  can be mounted on various electronic components and has high convenience and demand. 
     The acceleration sensor  5  includes a package  51  and sensor elements  54 ,  55 , and  56  accommodated in the package  51 . The package  51  includes a base  52  having a recess  521  formed so as to overlap the sensor elements  54 ,  55 , and  56 , and a lid  53  having a recess  531  that opens to a base  52  side and bonded to the base  52  so as to accommodate the sensor elements  54 ,  55 , and  56  in the recess  531 . A part of a lower surface of the base  52  is exposed from the lid  53 . A plurality of mounting terminals  59  electrically coupled to the sensor elements  54 ,  55 , and  56  are disposed in the exposed part. 
     The sensor element  54  is an element that detects the acceleration in the X axis direction. The sensor element  55  is an element that detects the acceleration in the Y axis direction. The sensor element  56  is an element that detects the acceleration in the Z axis direction. Each of the sensor elements  54 ,  55 , and  56  is a silicon vibration element including a fixed electrode fixed to the base  52  and a movable electrode variable with respect to the base  52 . When the acceleration in the detection axis direction is received, the movable electrode is displaced with respect to the fixed electrode, and the capacitance formed between the fixed electrode and the movable electrode changes. Therefore, a change in the capacitance of each of the sensor elements  54 ,  55 , and  56  is extracted as the detection signal. The acceleration in each axis direction can be obtained based on the extracted detection signal. 
     Although the acceleration sensor  5  is described above, the configuration of the acceleration sensor  5  is not particularly limited as long as the acceleration sensor  5  can exhibit its function. For example, the sensor elements  54 ,  55 , and  56  are not limited to the silicon vibration elements, and may be, for example, crystal vibration elements, and may be constituted to detect the acceleration based on the electric charge generated by vibration. 
     The circuit element  6  is an unpackaged semiconductor chip, that is, a bare chip. Accordingly, it is possible to reduce size and cost of the circuit element  6 . The circuit element  6  is not limited to the bare chip, and may be a packaged element. The circuit element  6  includes a control circuit  61  that controls driving of the angular velocity sensors  3   x ,  3   y , and  3   z  and the acceleration sensor  5 , and an interface circuit  62  that performs communication with the outside. The control circuit  61  independently controls the driving of the angular velocity sensors  3   x ,  3   y , and  3   z  and the acceleration sensor  5 , and independently detects the angular velocity around each axis of the X axis, the Y axis, and the Z axis and the acceleration in each axis direction based on the detection signals output from the angular velocity sensors  3   x ,  3   y , and  3   z  and the acceleration sensor  5 . The interface circuit  62  transmits and receives signals, receives a command from an external device, and outputs the detected angular velocity and acceleration to the external device. A communication method of the interface circuit  62  is not particularly limited. In the present embodiment, serial peripheral interface (SPI) communication is used. The SPI communication is a communication method suitable for coupling a plurality of sensors. Since all signals related to the angular velocity and the acceleration can be output from one lead  71 , pin saving of the electronic device  1  can be achieved. 
     The circuit element  6  includes a plurality of second mounting terminals  69  disposed on a lower surface thereof. The circuit element  6  is electrically coupled to the acceleration sensor  5  and the second wiring pattern  29  via a bonding wire BW. Accordingly, the circuit element  6  is electrically coupled to the angular velocity sensors  3   x ,  3   y , and  3   z , the acceleration sensor  5 , and the lead  71 . 
     The lead group  7  is located on the lower surface  22  side of the substrate  2 , and includes a plurality of leads  71  bonded to the substrate  2  via a conductive fourth bonding member B 4 . The plurality of leads  71  are provided substantially uniformly along the four sides of the substrate  2 . At least a part of the plurality of leads  71  is electrically coupled to the second wiring pattern  29  via the fourth bonding member B 4 , and is electrically coupled to the circuit element  6  via the second wiring pattern  29  and the bonding wire BW. The fourth bonding member B 4  is solder, and performs mechanical coupling and electrical coupling between the lead  71  and the substrate  2  by solder reflow. Accordingly, it is possible to easily and accurately couple the lead  71  and the substrate  2 . The fourth bonding member B 4  is less deteriorated over time and has high reliability. The fourth bonding member B 4  is not limited to solder. For example, various brazing materials such as gold brazing filler and silver brazing filler, various metal bumps such as gold bumps and silver bumps, and various conductive adhesives in which a conductive filler is dispersed in a resin-based adhesive can be used. 
     A free end portion of each lead  71  protrudes to the outside of the mold portion  9 , and the lead  71  is attached to the external device at this portion. That is, the electronic device  1  is a quad flat package (QFP). In the present embodiment, each lead  71  protruding from the mold portion  9  is bent downward in the middle thereof. However, the shape of each lead  71  is not particularly limited, and may be, for example, straight or bent upward. The electronic device  1  is not limited to the QFP, and may be, for example, a plastic leaded chip carrier (PLCC) in which the lead  71  protruding from the mold portion  9  is folded back to the lower side of the substrate  2 . 
     The mold portion  9  molds the acceleration sensor  5  and the circuit element  6 , and protects the acceleration sensor  5  and the circuit element  6  from moisture, dust, impact, and the like. The mold portion  9  molds a coupling portion between the substrate  2  and each lead  71 , and protects the coupling portion from moisture, dust, impact, and the like. The mold portion  9  bonds the cap  8  and the substrate  2 . A mold material constituting the mold portion  9  is not particularly limited. For example, a thermosetting epoxy resin or a curable resin material can be used. The mold portion  9  can be formed by, for example, a transfer molding method. 
     Here, as described above, the second electronic component  4  covered with the mold portion  9  is electrically coupled by the bonding wire BW. Therefore, even if the minute gap is formed in the mold portion  9  without being filled with the mold material and the second and third bonding members B 2  and B 3  melted by heat at the time of solder-mounting wet and spread in the minute gap, the electrical defects such as the short circuit, the disconnection, and the increase in the wiring resistance do not substantially occur. 
     The mold portion  9  includes a base portion  91  that is located on the lower surface  22  side of the substrate  2  and molds the second electronic component  4 , and a fixing portion  92  that is located on the side of the substrate  2 , molds a coupling portion between the substrate  2  and the lead  71 , and bonds the substrate  2  and the cap  8 . The fixing portion  92  has a substantially C-shaped cross section, bypasses the side of the substrate  2  from the lower surface  22  of the substrate  2  and goes around to the upper surface  21  side, and molds the flange portion  82  of the cap  8  to bond the substrate  2  and the cap  8 . 
     According to such a configuration, as described above, it is not necessary to dispose the adhesive between the substrate  2  and the cap  8  when the substrate  2  and the cap  8  are bonded to each other. Therefore, the height of the electronic device  1  can be reduced. There is no risk that the inside of the cap  8  may be contaminated by the outgas generated from the adhesive. Therefore, the electronic device  1  is small and has high reliability. In particular, by molding the flange portion  82 , the gap between the cap  8  and the substrate  2  can be closed by the mold material, so that the inside of the cap  8  can be hermetically sealed more reliably. 
     The mold portion  9  molds only from a central portion to an outer peripheral side end portion of the flange portion  82 , and a portion on the inner peripheral side of the flange portion  82  is not molded. That is, the flange portion  82  includes a mold region  821  covered with the mold portion  9  and a non-mold region  822  not covered with the mold portion  9 . The mold region  821  is provided on the outer peripheral side of the flange portion  82  with respect to the non-mold region  822 . By forming the non-mold region  822  in the flange portion  82  in this way, as will be described later, when the mold portion  9  is formed, the cap can be easily supported by the mold, the manufacturing of the electronic device  1  is facilitated, and accuracy thereof is improved. 
     Next, a method of manufacturing the electronic device  1  will be described. As shown in  FIG.  4   , the manufacturing step of the electronic device  1  includes a preparation step S 1  of preparing the substrate  2  on which the first electronic component  3  and the second electronic component  4  are mounted and to which the leads  71  are bonded, a molding step S 2  of forming the mold portion  9  in a state where the substrate  2  is covered with the cap  8 , and a lead shaping step S 3  of shaping the leads  71 . 
     Preparation Step S 1   
     First, the substrate  2  is prepared in which the first wiring pattern  28  is formed on the upper surface  21 , the second wiring pattern  29  is formed on the lower surface  22 , and the first wiring pattern  28  and the second wiring pattern  29  are electrically coupled to each other by a through electrode which is not shown. Next, a lead frame  70  shown in  FIG.  5    is prepared. The lead frame  70  includes a frame-shaped frame  73 , the plurality of leads  71  located inside the frame  73  and supported by the frame  73 , and tie bars  74  coupling the plurality of leads  71 . 
     Next, as shown in  FIG.  6   , the leads  71  are bonded to the lower surface  22  of the substrate  2  via the fourth bonding member B 4 . Specifically, a cleaning solder paste is used as the fourth bonding member B 4 . The leads  71  are bonded to the substrate  2  by the solder reflow. A narrow constriction portion is formed on an immediate tip end side of the bonding portion of each lead  71  to the substrate  2 . Accordingly, it is possible to prevent wetting and spreading of the fourth bonding member B 4  to the tip end side of the lead  71  at the time of the solder reflow. 
     Next, a flux residue generated by the solder reflow is cleaned and removed. Accordingly, the mold material is easily filled in the portion, so that the mold portion  9  with higher accuracy can be formed. It is also possible to effectively prevent corrosion or the like caused by re-melting of the flux residue at the time of subsequent solder reflow. 
     Next, the angular velocity sensors  3   x ,  3   y , and  3   z  are prepared, and are mounted on the upper surface  21  of the substrate  2  via the first bonding member B 1  as shown in  FIG.  7   . Specifically, a non-cleaning solder paste is used as the first bonding member B 1 . The angular velocity sensors  3   x ,  3   y , and  3   z  are bonded to the substrate  2  by the solder reflow. Unlike the case of the lead  71 , the flux residue generated by the solder reflow is not cleaned and removed, and a solder mounting surface is kept covered with the flux residue. Accordingly, contact between the portion and the atmosphere can be prevented, and corrosion of the portion can be effectively prevented. 
     As described above, after the leads  71  are bonded to the substrate  2  by the solder reflow, the angular velocity sensors  3   x ,  3   y , and  3   z  are bonded to the substrate  2  by the solder reflow, so that thermal damage to the angular velocity sensors  3   x ,  3   y , and  3   z  can be reduced. Therefore, it is possible to effectively prevent deterioration or fluctuation of the characteristics of each of the angular velocity sensors  3   x ,  3   y , and  3   z.    
     Next, the acceleration sensor  5  and the circuit element  6  are prepared. As shown in  FIG.  8   , the acceleration sensor  5  is bonded to the lower surface  22  of the substrate  2  via the second bonding member B 2 . The circuit element  6  is bonded to the lower surface of the acceleration sensor  5  via the third bonding member B 3 . As the second and third bonding members B 2  and B 3 , the die attach agent, the die attach film, or the like can be used. 
     After curing of the second and third bonding members B 2  and B 3  is completed, the bonding wire BW is formed to electrically couple each portion. A wire bonding step can be performed, for example, in a state where the substrate  2  is mounted on a heater block  1100  having a recess for preventing interference with the angular velocity sensors  3   x ,  3   y , and  3   z , and the substrate  2  is fixed by a clamper  1200 . A heating temperature of the substrate  2  is set to a relatively low temperature, for example, about 180° C. or more and 200° C. or less. Accordingly, thermal damage to the angular velocity sensors  3   x ,  3   y , and  3   z , the acceleration sensor  5 , and the circuit element  6  can be reduced. 
     Molding Step S 2   
     Next, the substrate  2  is molded in a state where the substrate  2  is covered with the cap  8  to form the mold portion  9 . In this step, a mold  2000  shown in  FIG.  9    is used. The mold  2000  includes a lower mold  2100  and an upper mold  2200 . 
     The lower mold  2100  includes a cap mounting portion  2110  on which the cap  8  is mounted, a mold material filling portion  2130  that is located outside the cap mounting portion  2110  and forms a space to be filled with the mold material, and a lead support portion  2140  that is located outside the mold material filling portion  2130  and supports the lead  71 . 
     The cap mounting portion  2110  includes a recess  2111  that opens on an upper surface side of the lower mold  2100  and has a shape conforming to an outer shape of the base portion  81  of the cap  8 , and a support portion  2112  that is located outside the recess  2111  and supports the flange portion  82  of the cap  8  from below. In a state in which the cap  8  is mounted in the cap mounting portion  2110 , the support portion  2112  comes into contact with the non-mold region  822  of the flange portion  82 , that is, a portion from the central portion to the inner peripheral side end portion of the flange portion  82 , and supports the portion from below. In this way, by supporting the flange portion  82  located at an outer edge portion of the cap  8 , a posture of the cap  8  is stabilized. Further, since the flange portion  82  is also a portion that comes into contact with the substrate  2 , a posture of the substrate  2  mounted on the cap  8  is stabilized by supporting the flange portion  82 . Therefore, the substrate  2  can be accurately located with respect to the cap  8 . What is important here is that the support portion  2112  does not come into contact with the mold region  821  of the flange portion  82 , that is, the portion from the central portion to the outer peripheral side end portion of the flange portion  82 . 
     The mold material filling portion  2130  is constituted by a recess recessed from the support portion  2112 , and overlaps the mold region  821  of the flange portion  82 , that is, the portion from the central portion to the outer peripheral side end portion of the flange portion  82  in the plan view. The mold material filling part  2130  forms a gap for pouring the mold material between the mold region  821  of the flange portion  82  and the lower mold  2100 . The lead support portion  2140  is located below the lead  71  and supports the lead  71  by sandwiching the lead  71  between the lead support portion  2140  and the upper mold  2200 . In a state in which the substrate  2  is merely mounted on the lower mold  2100 , that is, in a state in which the upper mold  2200  is not set, the lead support portion  2140  is not in contact with the lead  71 , and a gap G is formed therebetween. 
     On the other hand, the upper mold  2200  includes a mold material filling portion  2210  that forms a space for filling the mold material around the second electronic component  4 , and a lead pressing portion  2220  that is located outside the mold material filling portion  2210  and presses the lead  71  toward the lead support portion  2140 . The mold material filling portion  2210  is constituted by a recess that opens to a lower surface side. In a state in which the upper mold  2200  is set in the lower mold  2100 , the second electronic component  4  and a base end portion of each lead  71  are accommodated in the recess. Further, the mold material filling portion  2210  is coupled to the mold material filling portion  2130  at an outer edge portion thereof. One space to be filled with the mold material is formed by the mold material filling portions  2210  and  2130 . 
     In this step, first, the cap  8  is mounted in the cap mounting portion  2110 , and then the substrate  2  is mounted on the cap  8 . The cap  8  may be mounted in the cap mounting portion  2110  after the substrate  2  is mounted on the cap  8 . 
     Next, as shown in  FIG.  10   , the upper mold  2200  is set on the lower mold  2100 . In a state where the upper mold  2200  is set on the lower mold  2100 , the lead  71  is pressed toward the lead support portion  2140  by the lead pressing portion  2220  and is pressed against the lead support portion  2140 . Since the gap G is formed between the lead  71  and the lead support portion  2140 , the lead  71  is elastically deformed downward and is sandwiched between the lead support portion  2140  and the lead pressing portion  2220  in this state. Therefore, a restoring force F for returning to a natural state is generated in the lead  71 , and the substrate  2  is biased toward the cap  8  by the restoring force F and is pressed against the cap  8 . Accordingly, the cap  8  and the substrate  2  are brought into close contact with each other. Therefore, intrusion of the mold material into the cap  8  can be effectively prevented, and the cap  8  can be hermetically sealed more reliably. 
     In this state, the mold material filling portions  2210  and  2130  are filled with the heated and softened mold material, and the mold portion  9  is formed by cooling and curing the mold material. Accordingly, the mold portion  9  that covers the second electronic component  4  and bonds the cap  8  and the substrate  2  is formed. In particular, since the mold region  821  is located on the outer peripheral side of the flange portion  82  with respect to the non-mold region  822 , the bonding of the cap  8  and the substrate  2  and the hermetical sealing of the cap  8  can be easily and more reliably performed. 
     Lead Shaping Step S 3   
     Next, the frame  73  is removed from the lead frame  70 , and the lead  71  is bent into a predetermined shape. Next, the tie bar  74  coupling the leads  71  to each other is cut by a laser, a trim mold, or the like. Accordingly, the electronic device  1  shown in  FIG.  1    is manufactured. 
     According to such a manufacturing method, it is possible to more easily manufacture the electronic device  1  in which the electrical defects such as the short circuit, the disconnection, and the increase in the wiring resistance are less likely to occur. 
     The configuration and the manufacturing method of the electronic device  1  are described above. As described above, the electronic device  1  includes: the substrate  2  having the upper surface  21  that is the first surface and the lower surface  22  that is the second surface, which are in the front and back relationship with each other, with the first wiring pattern  28  being disposed on the upper surface  21  and the second wiring pattern  29  being disposed on the lower surface  22 ; the first electronic component  3  mounted on the upper surface  21  of the substrate  2 ; the second electronic component  4  mounted on the lower surface  22  of the substrate  2 ; and the mold portion that covers the second electronic component  4  without covering the first electronic component  3 . The first electronic component  3  includes the first mounting terminal  39  disposed on the first relative surface  320  relative to the upper surface  21 , and is bonded to the upper surface  21  via the conductive first bonding member B 1  on the first relative surface  320 , and the first mounting terminal  39  and the first wiring pattern  28  are electrically coupled to each other via the first bonding member B 1 . The second electronic component  4  includes the second mounting terminal  69 , and is bonded to the lower surface  22  via the second bonding member B 2  on the second relative surface  50  relative to the lower surface  22 , and the second mounting terminal  69  and the second wiring pattern  29  are electrically coupled to each other via the bonding wire BW which is a conductive wire. 
     Accordingly, the problem described in the related art, that is, the problem that the mold material cannot be fully filled in the gap formed between the angular velocity sensors  3   x ,  3   y , and  3   z  and the substrate  2  due to the thickness of the first joining member B 1 , and a minute gap is formed in the portion does not occur. Therefore, even if the first bonding member B 1  is melted by heat applied when the electronic device  1  is solder-mounted on the external substrate, unlike the related art, it is possible to effectively prevent wetting and spreading of the melted first bonding member B 1  to an unintended portion, and it is possible to effectively prevent the occurrence of the electrical defects such as the short circuit, the disconnection, and the increase in the wiring resistance. 
     As described above, the first bonding member B 1  is solder. Accordingly, mechanical coupling and electrical coupling between the angular velocity sensors  3   x ,  3   y , and  3   z  and the substrate  2  can be performed by the solder reflow. Therefore, the coupling can be easily and accurately performed. The first bonding member B 1  is less deteriorated over time. Therefore, the manufacturing of the electronic device  1  is facilitated, and the reliability of the electronic device  1  is improved. 
     As described above, the angular velocity sensors  3   x ,  3   y , and  3   z , which are the first electronic component  3 , are packaged surface mount components. Accordingly, the angular velocity sensors  3   x ,  3   y , and  3   z  are excellent in the mechanical strength and easy to be mounted on the substrate  2 . The second electronic component  4  includes the circuit element  6  electrically coupled to the angular velocity sensors  3   x ,  3   y , and  3   z . Accordingly, the angular velocity sensors  3   x ,  3   y , and  3   z  and the circuit element  6  can be coupled in the electronic device  1 , and the wiring for coupling the angular velocity sensors  3   x ,  3   y , and  3   z  and the circuit element  6  can be shortened. Therefore, noise is less likely to be added to the detection signals output from the angular velocity sensors  3   x ,  3   y , and  3   z , and the angular velocity around each axis can be accurately detected. 
     As described above, the circuit element  6  is a bare chip. Accordingly, it is possible to reduce the size and the cost of the circuit element  6 . 
     As described above, the angular velocity sensors  3   x ,  3   y , and  3   z  are physical quantity sensors each including the package  31  and the physical quantity detection element  34  accommodated in the package  31 . The circuit element  6  includes the interface circuit  62  that communicates with the outside. Accordingly, the electronic device  1  can be mounted on various electronic components and has high convenience and demand. 
     As described above, the first electronic component  3 , which is the physical quantity sensor, is the angular velocity sensors  3   x ,  3   y , and  3   z . The second electronic component  4  includes the acceleration sensor  5  in addition to the circuit element  6 . The acceleration sensor  5  is bonded to the lower surface  22 . The circuit element  6  is bonded to the acceleration sensor  5 . The circuit element  6  is electrically coupled to the angular velocity sensors  3   x ,  3   y , and  3   z  and the acceleration sensor  5  via the bonding wire BW. Accordingly, the electronic device  1  can be used as a composite sensor capable of independently detecting the angular velocity and the acceleration. Therefore, the electronic device  1  can be mounted on various electronic components and has high convenience and demand. Since the shape of the acceleration sensor  5  in the plan view is larger than the shape of the circuit element  6  in the plan view, the acceleration sensor  5  and the circuit element  6  can be disposed in a well-balanced manner by bonding the acceleration sensor  5  to the lower surface  22  and bonding the circuit element  6  to the acceleration sensor  5 . 
     As described above, the electronic device  1  includes the plurality of leads  71  bonded to the substrate  2  and electrically coupled to the second wiring pattern  29 . The coupling portion between the substrate  2  and the leads  71  is covered with the mold portion  9 . Accordingly, it is possible to protect the coupling portion from moisture, dust, impact, and the like. 
     As described above, the electronic device  1  includes the cap  8  which includes the base portion  81  having the recess  811  that opens to the upper surface  21  side, and the flange portion  82  protruding from the end portion of the base portion  81  on the upper surface  21  side, which is disposed on the upper surface  21  so as to accommodate the first electronic component  3  in the recess  811 , and in which the flange portion  82  is in contact with the upper surface  21 . The flange portion  82  is bonded to the substrate  2  by the mold portion  9 . Accordingly, the height of the electronic device  1  can be reduced. It is also possible to prevent contamination of the inside of the cap  8 . Therefore, the electronic device  1  is small and has high reliability. 
     As described above, the substrate  2  is a ceramic substrate. Accordingly, the substrate  2  having high corrosion resistance is obtained. The substrate  2  having excellent mechanical strength is obtained. Therefore, the electronic device  1  having excellent long-term reliability is obtained. 
     Second Embodiment 
       FIG.  11    is a cross-sectional view showing an electronic device according to a second embodiment. 
     The present embodiment is the same as the first embodiment described above except that the arrangement of the acceleration sensor  5  and the circuit element  6  is different. In the following description, the present embodiment will be described with a focus on the difference from the above embodiment, and a description of similar matters will be omitted. In  FIG.  11   , the same reference numerals are given to configurations similar to those according to the above embodiment. 
     As shown in  FIG.  11   , in the electronic device  1  according to the present embodiment, the circuit element  6  is bonded to the lower surface  22  via the second bonding member B 2  on the upper surface thereof, that is, a second relative surface  600  relative to the lower surface  22  of the substrate  2 . The acceleration sensor  5  is bonded to the lower surface of the circuit element  6  via the third bonding member B 3  on the upper surface thereof, that is, a third relative surface  500  relative to the lower surface of the circuit element  6 . In the present embodiment, since a shape of the circuit element  6  in a plan view is larger than a shape of the acceleration sensor  5  in the plan view, the circuit element  6  is bonded to the substrate  2 , and the acceleration sensor  5  is bonded to the circuit element  6 . Accordingly, the acceleration sensor  5  and the circuit element  6  can be disposed on the substrate  2  in a well-balanced manner. 
     As described above, in the electronic device  1  according to the present embodiment, the first electronic component  3 , which is a physical quantity sensor, is the angular velocity sensors  3   x ,  3   y , and  3   z . The second electronic component  4  includes the acceleration sensor  5  in addition to the circuit element  6 . The circuit element  6  is bonded to the lower surface  22 . The acceleration sensor  5  is bonded to the circuit element  6 . The circuit element  6  is electrically coupled to the angular velocity sensors  3   x ,  3   y , and  3   z  and the acceleration sensor  5  via the bonding wire BW. Accordingly, the electronic device  1  can be used as a composite sensor capable of independently detecting the angular velocity and the acceleration. Therefore, the electronic device  1  can be mounted on various electronic components and has high convenience and demand. Since the shape of the circuit element  6  in the plan view is larger than the shape of the acceleration sensor  5  in the plan view, the circuit element  6  and the acceleration sensor  5  can be disposed in the well-balanced manner by bonding the circuit element  6  to the lower surface  22  and bonding the acceleration sensor  5  to the circuit element  6 . 
     Even with such a second embodiment, the same effects as those of the first embodiment can be exerted. 
     Third Embodiment 
       FIG.  12    is a cross-sectional view showing an electronic device according to a third embodiment. 
     The present embodiment is the same as the second embodiment described above except that the second electronic component  4  is electrically coupled to the second wiring pattern  29  via the second bonding member B 2  instead of the bonding wire BW. In the following description, the present embodiment will be described with a focus on the difference from the above embodiments, and a description of similar matters will be omitted. In  FIG.  12   , the same reference numerals are given to configurations similar to those according to the above embodiments. 
     As shown in  FIG.  12   , in the circuit element  6  according to the present embodiment, a plurality of second mounting terminals  69  are disposed not only on the lower surface but also on the second relative surface  600  relative to the lower surface  22  of the substrate  2 . The circuit element  6  is bonded to the lower surface  22  of the substrate  2  via the conductive second bonding member B 2  on the second relative surface  600 . The second mounting terminal  69  is electrically coupled to the second wiring pattern  29  via the second bonding member B 2 . The second bonding member B 2  is various metal bumps such as gold bumps and silver bumps. Accordingly, it is possible to easily and accurately couple the circuit element  6  and the substrate  2 . 
     The second bonding member B 2  has a melting point higher than that of the solder as the first bonding member B 1 . More specifically, the second bonding member B 2  has such a melting point that the second bonding member B 2  is not melted by heat applied during a manufacturing step of the electronic device  1  or during solder reflow when the electronic device  1  is solder-mounted. The melting point of the second bonding member B 2  is not particularly limited, and is preferably higher than the melting point of the solder as the first bonding member B 1  by 50° C. or more, and more preferably by 100° C. or more. Accordingly, it is possible to effectively prevent melting of the second bonding member B 2  at the time of the solder reflow. 
     By setting a melting point of the second bonding member B 2  to be higher than a melting point of the solder which is the first bonding member B 1 , the following effects can be exerted. In the present embodiment, a gap G 1  is formed between the circuit element  6  and the substrate  2  by a thickness of the second bonding member B 2 . Therefore, similarly to the related art, the gap G 1  is not sufficiently filled with the mold material, and a minute gap may be generated in the portion. However, the second bonding member B 2  does not melt even by solder reflow, and does not wet and spread in the minute gap. Therefore, it is possible to effectively prevent the occurrence of electrical defects such as a short circuit, a disconnection, and an increase in wiring resistance. 
     The electronic device  1  is described above. The electronic device  1  includes: the substrate  2  having the upper surface  21  that is the first surface and the lower surface  22  that is the second surface, which are in the front and back relationship with each other, with the first wiring pattern  28  being disposed on the upper surface  21  and the second wiring pattern  29  being disposed on the lower surface  22 ; the first electronic component  3  mounted on the upper surface  21  of the substrate  2 ; the second electronic component  4  mounted on the lower surface  22  of the substrate  2 ; and the mold portion  9  that covers the second electronic component  4  without covering the first electronic component  3 . The first electronic component  3  includes the first mounting terminal  39  disposed on the first relative surface  320  relative to the upper surface  21 , and is bonded to the upper surface  21  via the conductive first bonding member B 1  on the first relative surface  320 , and the first mounting terminal  39  and the first wiring pattern  28  are electrically coupled to each other via the first bonding member B 1 . The second electronic component  4  includes the second mounting terminal  69  disposed on the second relative surface  600  relative to the lower surface  22 , and is bonded to the lower surface  22  on the second relative surface  600  via the conductive second bonding member B 2  having the melting point higher than that of the first bonding member B 1 , and the second mounting terminal  69  and the second wiring pattern  29  are electrically coupled to each other via the second bonding member B 2 . 
     Accordingly, even if the mold material cannot be fully filled into the gap formed between the circuit element  6  and the substrate  2  due to the thickness of the second bonding member B 2 , and a minute gap is formed at the portion, it is possible to prevent the wetting and spreading of the second bonding member B 2  in the minute gap. Therefore, it is possible to effectively prevent the occurrence of the electrical defects such as the short circuit, the disconnection, and the increase in the wiring resistance. 
     As described above, the second bonding member B 2  is a metal bump. Accordingly, it is possible to easily and accurately couple the circuit element  6  and the substrate  2 . 
     Even in such a third embodiment as described above, the same effects as in the above described first embodiment can be obtained. 
     As mentioned above, although the electronic device according to the present disclosure is described based on illustrated embodiments, the present disclosure is not limited thereto. A configuration of each part can be replaced with any configuration having a similar function. Further, any other constituents may be added to the present disclosure. The embodiments may be combined as appropriate.