JP2016003993A - Electronic device, method of manufacturing electronic device, electronic apparatus, and mobile body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic device capable of reducing an external force applied to an electronic component, and also to provide a method of manufacturing the electronic device, an electronic apparatus, and a mobile body.SOLUTION: An electronic device 1 includes: an IC chip 4; a pressure sensor element 3; a bonding wire 15 which electrically connects the IC chip 4 and the pressure sensor element 3; and a bonding wire 13 which connects the IC chip 4 and the pressure sensor element 3 so that stress generated in the pressure sensor element 3 by connecting the bonding wire 15 is reduced.

Description

  The present invention relates to an electronic device, an electronic device manufacturing method, an electronic apparatus, and a moving body.

  For example, in the electronic component described in Patent Document 1, the electrode pad is connected to an external terminal via a bonding wire. In addition, this electronic component has a cavity for relaxing external stress generated from the bonding wire below (directly below) the electrode pad. However, even with such a configuration, particularly when the bonding wires are arranged non-uniformly (asymmetric), external stress is generated due to the non-uniformity. For this reason, the sensor accuracy (characteristic) decreases.

JP 2008-235487 A

  The objective of this invention is providing the electronic device which can reduce the external stress added to an electronic component, the manufacturing method of an electronic device, an electronic device, and a moving body.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following application examples.

[Application Example 1]
The electronic device of this application example includes a wiring board,
Electronic components,
A first wire that electrically connects the wiring board and the electronic component;
It has a 2nd wire which has connected the said wiring board and the said electronic component so that the stress which arises in the said electronic component with the said 1st wire may be adjusted, It is characterized by the above-mentioned.

  Thereby, it becomes an electronic device which can reduce the external stress (unnecessary stress) applied to the electronic component.

[Application Example 2]
In the electronic device of this application example, the electronic device includes a plurality of the first wires,
It is preferable that the arrangement of the first wires is asymmetric with respect to the central portion of the electronic component in plan view.
Thereby, the freedom degree of arrangement | positioning of a 1st wire increases.

[Application Example 3]
In the electronic device according to this application example, it is preferable that the second wire is not electrically connected to the wiring board.

  As a result, unintended short circuits, parasitic capacitance, noise, and the like can be reduced.

[Application Example 4]
In the electronic device according to this application example, it is preferable that the second wire is not electrically connected to the electronic component.

  As a result, unintended short circuits, parasitic capacitance, noise, and the like can be reduced.

[Application Example 5]
In the electronic device of this application example, it is preferable that a circuit is provided on the wiring board.
Thereby, the output from an electronic component etc. can be processed with a wiring board.

[Application Example 6]
In the electronic device according to this application example, it is preferable that the electronic component is a pressure sensor element having a diaphragm.

  Thereby, an electronic apparatus can be used as a pressure sensor apparatus, and the convenience increases.

[Application Example 7]
In the electronic device according to this application example, it is preferable that the first wire and the second wire include the same metal material as a main material.

  Thereby, commonality with the 1st wire and the 2nd wire can be aimed at, and the device composition becomes simple.

[Application Example 8]
In the electronic device according to this application example, it is preferable that the wiring board and the electronic component are directly connected by the first wire and the second wire.
Thereby, the total length of the wiring is shortened, and the generation of noise can be reduced.

[Application Example 9]
The manufacturing method of the electronic device of this application example includes a step of connecting the wiring board and the electronic component with a plurality of first wires and a plurality of second wires,
Measuring the electronic component;
And a step of releasing at least one of the plurality of connections by the second wires based on a measurement result in the measuring step, if necessary.

  As a result, an electronic device that can reduce external stress (unnecessary stress) applied to the electronic component can be obtained.

[Application Example 10]
In the electronic device manufacturing method according to this application example, it is preferable that the electrical characteristics of the electronic component are measured in the measuring step.
Thereby, the stress applied to the electronic component can be appropriately measured (estimated).

[Application Example 11]
In the manufacturing method of the electronic device according to this application example, it is preferable that the second wire is cut in the releasing step.
Thereby, the connection of the second wire can be easily released.

[Application Example 12]
In the manufacturing method of the electronic device according to this application example, in the releasing step, it is preferable to cut or remove the second wire using a laser.
Thereby, a 2nd wire can be cut | disconnected or removed easily.

[Application Example 13]
The manufacturing method of the electronic device of this application example includes a step of connecting the wiring board and the electronic component with a plurality of first wires and second wires,
Measuring the electronic component;
A step of adding the second wire for connecting the wiring board and the electronic component, if necessary, based on a measurement result in the measuring step.

  As a result, an electronic device that can reduce external stress (unnecessary stress) applied to the electronic component can be obtained.

[Application Example 14]
An electronic apparatus according to this application example includes the electronic device according to the application example described above.
As a result, a highly reliable electronic device can be obtained.

[Application Example 15]
The moving body of this application example includes the electronic device of the above application example.
Thereby, a mobile body with high reliability is obtained.

It is sectional drawing which shows the electronic device which concerns on 1st Embodiment of this invention. It is a top view of the electronic device shown in FIG. It is sectional drawing which shows the pressure sensor element which the electronic device shown in FIG. 1 has. It is a top view which shows the pressure sensor part which the pressure sensor element shown in FIG. 3 has. It is a figure which shows the circuit containing the pressure sensor part shown in FIG. It is a figure for demonstrating the function of the 2nd wire with which the electronic apparatus shown in FIG. 1 is provided. It is a figure for demonstrating the function of the 2nd wire with which the electronic apparatus shown in FIG. 1 is provided. It is a top view for demonstrating the manufacturing method of the electronic device shown in FIG. It is a top view for demonstrating the manufacturing method of the electronic device shown in FIG. It is a top view for demonstrating the manufacturing method of the electronic device shown in FIG. It is a top view for demonstrating another manufacturing method of the electronic device shown in FIG. It is a top view for demonstrating another manufacturing method of the electronic device shown in FIG. It is a top view which shows the electronic device which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows the electronic device which concerns on 3rd Embodiment of this invention. FIG. 15 is a plan view of the electronic device shown in FIG. 14. It is sectional drawing which shows the electronic device which concerns on 4th Embodiment of this invention. FIG. 17 is a plan view of the electronic device shown in FIG. 16. It is a front view which shows the navigation system which is an example of the electronic device of this invention. It is a perspective view which shows the altimeter which is an example of the electronic device of this invention. It is a perspective view which shows an example of the moving body of this invention.

  Hereinafter, an electronic device, a method for manufacturing the electronic device, an electronic apparatus, and a moving body of the present invention will be described in detail based on embodiments shown in the accompanying drawings.

<First Embodiment>
FIG. 1 is a cross-sectional view showing an electronic device according to a first embodiment of the present invention. FIG. 2 is a plan view of the electronic device shown in FIG. FIG. 3 is a cross-sectional view showing a pressure sensor element included in the electronic device shown in FIG. 4 is a plan view showing a pressure sensor unit included in the pressure sensor element shown in FIG. FIG. 5 is a diagram showing a circuit including the pressure sensor unit shown in FIG. 6 and 7 are diagrams for explaining the function of the second wire included in the electronic device shown in FIG. 8 to 10 are plan views for explaining a method of manufacturing the electronic device shown in FIG. 11 and 12 are plan views for explaining another method for manufacturing the electronic device shown in FIG. In the following description, the upper side in FIGS. 1 and 3 is referred to as “upper” and the lower side is referred to as “lower”.

  An electronic device 1 shown in FIG. 1 houses a pressure sensor element (electronic component) 3, an IC chip (wiring board) 4 electrically connected to the pressure sensor element 3, and the pressure sensor element 3 and the IC chip 4. And a filler 11 surrounding the pressure sensor element 3 and the IC chip 4 in the package 2. Hereinafter, each of these units will be described in order.

≪Package≫
The package 2 has a function of accommodating (fixing) the pressure sensor element 3 in an internal space 28 formed therein.

  As shown in FIG. 1, the package 2 includes a base 21, a housing 22, and a flexible wiring board (supporting board) 25, and the flexible wiring board 25 is sandwiched between the base 21 and the housing 22. In this way, these are joined together. Bonding between the base 21 and the flexible wiring board 25 and bonding between the housing 22 and the flexible wiring board 25 are performed via an adhesive layer 26 made of an adhesive.

  The base 21 constitutes the bottom surface of the package 2. In the present embodiment, the overall shape is a flat plate shape, and the planar view shape is a square shape. The constituent material of the base 21 is not particularly limited. For example, various ceramics such as oxide ceramics such as alumina, silica, titania and zirconia, nitride ceramics such as silicon nitride, aluminum nitride and titanium nitride, polyethylene, Insulating materials such as various resin materials such as polyamide, polyimide, polycarbonate, acrylic resin, ABS resin, and epoxy resin can be used, and one or more of these can be used in combination. Among these, various ceramics are preferable. Thereby, the package 2 having excellent mechanical strength can be obtained. In addition, as the planar view shape of the base 21, for example, a circular shape, a rectangular shape, a polygonal shape of pentagon or more, and the like may be used.

  The housing 22 constitutes a lid portion of the package 2, and in this embodiment, the overall shape is a cylindrical shape. Further, the housing 22 has a portion where the outer diameter and inner diameter gradually decrease from the lower end toward the upper end to the middle of the package height. As the constituent material of the housing 22, the same materials as those mentioned as the constituent material of the base 21 can be used. The shape of the housing 22 is not particularly limited.

  The flexible wiring board 25 is located between the base 21 and the housing 22 in the thickness direction of the package 2, and supports the pressure sensor element 3 and the IC chip 4 in the package 2. It has a function of taking out an electrical signal from the IC chip 4 to the outside of the package 2. Such a flexible wiring board 25 includes a flexible base material 23 and a wiring 24 formed on the lower surface side of the base material 23.

  In addition, as shown in FIG. 2, the base material 23 is formed integrally with a frame portion 231 having a substantially rectangular frame shape and having an opening 233 at the center, and protruding on one side of the frame portion 231. And a belt body 232 having a belt shape. The constituent material of the base material 23 is not particularly limited as long as it has flexibility, and examples thereof include polyimide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyethersulfone (PES). Of these, one or two or more of these can be used in combination.

  The wiring 24 has conductivity, and is provided (routed) over the frame portion 231 and the band body 232 as shown in FIG. Such wiring 24 includes four wiring parts 241 that electrically connect the pressure sensor element 3 and the IC chip 4, and four wiring parts 245 that electrically connect the IC chip 4 and the outside of the electronic device 1. And three wiring portions 249 for stress adjustment used for adjusting / relaxing unnecessary stress applied to the pressure sensor element 3.

  The four wiring parts 241 are arranged side by side along one side 231a of the frame part 231. Each wiring portion 241 is electrically connected to the connection terminal 743 of the pressure sensor element 3 via the bonding wire (first wire) 15 at one end portion (end portion on the side 231a side). . Further, the pressure sensor element 3 is supported by the bonding wire 15 in a state of being separated from the frame portion 231 and floating with respect to the frame portion 231. Each wiring part 241 is electrically connected to the connection terminal 42 of the IC chip via the bonding wire 14 at the other end. As a result, the pressure sensor element 3 and the IC chip 4 are electrically connected via the wiring portion 241.

  On the other hand, each of the four wiring portions 245 has a base end side provided in the band body 232 and a tip end side provided in the frame portion 231. Moreover, the front-end | tip part of the four wiring parts 245 is arrange | positioned along the edge | side 231b facing the edge | side 231a. The wiring portions 245 are electrically connected to the connection terminals 42 of the IC chip 4 via the bonding wires 16, respectively. The bonding wire 16 and the bonding wire 14 described above support the pressure sensor element 3 in a state of being separated from the frame portion 231 and the pressure sensor element 3 and floating with respect to the frame portion 231.

  Further, the three wiring portions 249 are arranged along the side 231b. In addition, the wiring part 249 is disposed to face the wiring part 241 with the pressure sensor element 3 interposed therebetween in plan view. In addition, the wiring portion 249 is spaced apart from the wiring portions 241 and 245 and is not electrically connected to the wiring portions 241 and 245. Further, the wiring portion 249 extends so as to be away from the pressure sensor element 3 substantially perpendicular to the side 231b.

  Each of these wiring portions 249 is connected to a stress correction terminal 744 of the pressure sensor element 3 via a bonding wire (second wire) 13. That is, the pressure sensor element 3 is supported on one side by the bonding wire 15 and is supported on both sides by being supported on the other side by the bonding wire 13. Here, unlike the bonding wire 15, the bonding wire 13 is not electrically connected to the pressure sensor element 3 or the IC chip 4. That is, the bonding wire 13 is not used for electrical connection between the pressure sensor element 3 and the IC chip 4 or electrical connection between the IC chip 4 and the outside. Thereby, a short circuit due to the bonding wire 13, generation of parasitic capacitance, generation of noise, and the like can be prevented, and the electronic device 1 having more excellent characteristics can be obtained. Such a bonding wire 13 reduces (adjusts) a decrease in pressure sensing ability of the pressure sensor element 3 by offsetting or mitigating stress (distortion) generated in the pressure sensor element 3 due to connection with the bonding wire 15. It has a function. This function will be described in detail later.

  In addition, although it does not specifically limit as a constituent material of the bonding wires 13 and 15, For example, various metals, such as gold | metal | money, copper, aluminum, an alloy containing these metals, etc. can be used. Moreover, it is preferable that the bonding wires 13 and 15 contain the mutually same material as a main material, and it is more preferable that it is the same structure. Moreover, it is preferable that the wire diameter is also the same. Thereby, the bonding wires 13 and 15 can be made common, and the configuration of the apparatus becomes simple. However, the bonding wires 13 and 15 may be made of different materials, or may have different wire diameters.

  The package 2 has been described above. According to the package 2 having such a configuration, for example, an electronic device described later or a mother board of a moving body is electrically connected to the end portion of the wiring portion 245 so that the pressure sensor element 3 and the IC chip 4 can be connected. An electric signal can be taken out of the package 2.

Note that the number of the wiring portions 241 and 245 included in the wiring 24 is not particularly limited. What is necessary is just to set suitably collectively. Further, the number of wiring portions 249 is not particularly limited, and can be set as appropriate based on the magnitude of the stress generated in the pressure sensor element 3 due to the connection with the bonding wire 15. In addition, the constituent material of the wiring 24 is not particularly limited as long as it has conductivity. For example, metals such as Ni, Pt, Li, Mg, Sr, Ag, Cu, Co, and Al, these An alloy such as MgAg, AlLi, or CuLi containing oxide, an oxide such as ITO, SnO _2, or the like can be used, and one or more of these can be used in combination.

≪Pressure sensor≫
The pressure sensor element 3 is an element capable of detecting the received pressure, and as shown in FIG. 3, the substrate 5, the pressure sensor part 6, the element surrounding structure 7, the cavity part 8, and not shown. And a semiconductor circuit. Hereinafter, each of these units will be described in order.

The substrate 5 has a plate shape and is formed on a semiconductor substrate 51 formed of an SOI substrate (a substrate in which the first Si layer 511, the SiO ₂ layer 512, and the second Si layer 513 are stacked in this order) The first insulating film 52 made of a silicon oxide film (SiO ₂ film) and the second insulating film 53 made of a silicon nitride film (SiN film) are stacked in this order. However, the semiconductor substrate 51 is not limited to an SOI substrate, and for example, a silicon substrate can be used.

  Further, the semiconductor substrate 51 is provided with a diaphragm 54 that is thinner than the surrounding portion and bends and deforms by receiving pressure. The diaphragm 54 is formed by providing a bottomed recess 55 on the lower surface of the semiconductor substrate 51, and the lower surface (the bottom surface of the recess 55) serves as a pressure receiving surface 541.

  A semiconductor circuit (circuit) (not shown) is formed on and above the semiconductor substrate 51. This semiconductor circuit includes circuit elements such as active elements such as MOS transistors, capacitors, inductors, resistors, diodes, and wirings formed as necessary.

  As shown in FIG. 4, the pressure sensor unit (output signal unit) 6 includes four piezoresistive elements 61, 62, 63, and 64 provided in the diaphragm 54. These four piezoresistive elements 61, 62, 63, and 64 are provided corresponding to the respective sides of the diaphragm 54 that forms a quadrangle in plan view.

  The piezoresistive elements 61 and 62 include piezoresistive portions 611 and 621 provided on the outer edge portion of the diaphragm 54, and wirings 613 and 623 connected to both ends of the piezoresistive portions 611 and 621. Yes. On the other hand, the piezoresistive elements 63 and 64 include a pair of piezoresistive parts 631 and 641 provided on the outer edge of the diaphragm 54 and a connection part 632 that connects the pair of piezoresistive parts 631 and 641. 642 and wirings 633 and 643 connected to the other ends of the pair of piezoresistive parts 631 and 641.

  The piezoresistive portions 611, 621, 631, and 641 are configured by doping (diffusing or implanting) impurities such as phosphorus and boron into the first Si layer 511 of the semiconductor substrate 51, for example. In addition, the wirings 613, 623, 633, 643 and the connection portions 632, 642 are formed of, for example, phosphorus, boron, etc. at a higher concentration than the piezoresistive portions 611, 621, 631, 641, It is configured by doping impurities (diffusion or implantation).

  Further, the piezoresistive elements 61, 62, 63, 64 are configured so that the resistance values in the natural state are equal to each other. These piezoresistive elements 61, 62, 63, 64 are electrically connected to each other via wirings 613, 623, 633, 643, etc., and as shown in FIG. 5, a bridge circuit 60 (Wheatstone bridge circuit) is provided. ) And is connected to the semiconductor circuit. The bridge circuit 60 is connected to a drive circuit (not shown) for supplying a drive voltage AVDC. The bridge circuit 60 outputs a signal (voltage) corresponding to the resistance values of the piezoresistive elements 61, 62, 63, and 64.

  The element surrounding structure 7 is formed so as to define the cavity 8. As shown in FIG. 3, the element surrounding structure 7 includes an interlayer insulating film 71, a wiring layer 72 formed on the interlayer insulating film 71, and an interlayer insulating film formed on the wiring layer 72 and the interlayer insulating film 71. A film 73, a wiring layer 74 formed on the interlayer insulating film 73, a surface protective film 75 formed on the wiring layer 74 and the interlayer insulating film 73, and a sealing layer 76 are included. The wiring layer 74 has a coating layer 741 having a plurality of pores 742 communicating with the inside and outside of the cavity 8, and the sealing layer 76 disposed on the coating layer 741 seals the pores 742. doing. Note that the wiring layers 72 and 74 include a wiring layer formed so as to surround the cavity 8 and a wiring layer that constitutes the wiring of the semiconductor circuit. The semiconductor circuit is drawn to the upper surface of the pressure sensor element 3 by the wiring layers 72 and 74, a part of the wiring layer 74 serves as a connection terminal 743, and the connection terminal 743 is exposed from the surface protective film 75. The connection terminal 743 is electrically connected to the wiring portion 241 through the bonding wire 15.

  As shown in FIG. 3, a part of the wiring layer 74 serves as a stress correction terminal 744, and the stress correction terminal 744 is exposed from the surface protective film 75. The stress correction terminal 744 is connected to the wiring portion 249 through the bonding wire 13. Note that the stress correction terminal 744 is preferably not electrically connected to the semiconductor circuit. Thereby, the electrical connection between the bonding wire 13 and the semiconductor circuit can be prevented.

The interlayer insulating films 71 and 73 are not particularly limited. For example, an insulating film such as a silicon oxide film (SiO ₂ film) can be used. Further, the wiring layers 72 and 74 are not particularly limited, but for example, a metal film such as an aluminum film can be used. In addition, the sealing layer 76 is not particularly limited, but a metal film such as Al, Cu, W, Ti, TiN, or the like can be used. Further, the surface protective film 75 is not particularly limited, but a film having resistance to protect the element from moisture, dust, scratches, etc., such as a silicon oxide film, a silicon nitride film, a polyimide film, and an epoxy resin film is used. Can do.

  A cavity 8 defined by the substrate 5 and the element surrounding structure 7 is a sealed space, and functions as a pressure reference chamber serving as a reference value of pressure detected by the pressure sensor element 3. Such a cavity portion 8 is located on the side opposite to the pressure receiving surface 541 of the diaphragm 54 and is disposed so as to overlap the diaphragm 54. The diaphragm 54 constitutes a part of the wall that defines the cavity 8. The cavity 8 is in a vacuum state (for example, 10 Pa or less). As a result, the pressure sensor element 3 can be used as a so-called “absolute pressure sensor element” that detects pressure based on a vacuum state. However, the cavity 8 may not be in a vacuum state, and may be, for example, an atmospheric pressure state, a reduced pressure state where the atmospheric pressure is lower than the atmospheric pressure, or an atmospheric pressure higher than the atmospheric pressure. It may be in a pressurized state.

≪IC chip≫
As shown in FIGS. 1 and 2, the IC chip 4 is provided with a semiconductor circuit 41. The semiconductor circuit 41 includes circuit elements such as an active element such as a MOS transistor, a capacitor, an inductor, a resistor, a diode, and a wiring as necessary. Such a semiconductor circuit 41 is electrically connected to the wiring portions 241 and 245 via connection terminals 42 arranged on the upper surface (the surface on the pressure sensor element 3 side).

  Here, the semiconductor circuit 41 in the IC chip 4 and the semiconductor circuit in the pressure sensor element 3 include, for example, a drive circuit for supplying a voltage to the bridge circuit 60 and an output from the bridge circuit 60 of the pressure sensor. A temperature compensation circuit that performs temperature compensation according to temperature, an output circuit that converts an output from the temperature compensation circuit into a predetermined output format (CMOS, LV-PECL, LVDS, etc.), and the like are included. The arrangement of the drive circuit, the temperature compensation circuit, the output circuit, and the like is not particularly limited. For example, the drive circuit is formed in the semiconductor circuit in the pressure sensor element 3, and the temperature compensation circuit and the semiconductor circuit 41 in the IC chip 4 are formed. An output circuit may be formed. Thus, by providing the IC chip 4 having the semiconductor circuit 41 separately from the pressure sensor element 3, for example, the IC chip 4 is omitted and the semiconductor circuit 41 is formed in the pressure sensor element 3. Thus, the electronic device 1 can be downsized.

  The pressure sensor element 3 and the IC chip 4 have been described above. As described above, the pressure sensor element 3 is bonded to the wiring portion 241 via the bonding wire 15 and is bonded to the wiring portion 249 via the bonding wire 13. Accordingly, the pressure sensor element 3 is supported by the frame portion 231 and each connection terminal 743 is electrically connected to the wiring portion 241. On the other hand, as described above, the IC chip 4 is joined to the wiring parts 241 and 245 via the bonding wires 14 and 16, whereby the IC chip 4 is supported by the frame part 231 and each connection is made. The terminal 42 is electrically connected to the wiring parts 241 and 245. As a result, the pressure sensor element 3 and the IC chip 4 are electrically connected via the wiring portion 241, and can be output from the IC chip 4 to the outside by the wiring portion 245.

  As shown in FIG. 1, the pressure sensor element 3 and the IC chip 4 fixed in this manner are floated in the internal space 28 of the package 2 by the bonding wires 13, 14, 15, 16 and the filler 11. It is in the state (the state which is not in contact with the inner wall). This makes it difficult for vibrations and the like to be transmitted to the pressure sensor element 3 and the IC chip 4 via the package 2, so that a decrease in pressure detection accuracy by the electronic device 1 can be suppressed. In addition, since the pressure sensor element 3 is disposed so as to overlap the IC chip 4 in a plan view (arranged vertically), the electronic device 1 can be reduced in size.

  Moreover, in this embodiment, the four bonding wires 15 are arrange | positioned asymmetrically with respect to center part O (diaphragm 54) of the pressure sensor element 3 by planar view. Specifically, all the bonding wires 15 extend toward the side 231 a of the frame portion 231. As described above, the asymmetric arrangement with respect to the central portion O increases the degree of freedom of arrangement of the wiring 24 (wiring portion 241) as compared with, for example, a symmetrical arrangement with respect to the central portion O. Therefore, the design of the electronic device 1 becomes easier.

  Next, the function of the bonding wire 13 will be described in detail. As described above, in the present embodiment, since the pressure sensor element 3 is supported on the side 231a side by the four bonding wires 15, if the bonding wire 13 is not provided, as shown in FIG. A stress B that bends the pressure sensor element 3 may be applied to the pressure sensor element 3 by the tension A of the bonding wire 15. Further, with such a configuration, it is relatively difficult to control the posture of the pressure sensor element 3, and the pressure sensor element 3 may be inclined. There is a possibility that the generation of the stress B whose posture is inclined is promoted, or the pressure sensor element 3 comes into contact with the IC chip 4 and the like, and unnecessary stress is further applied by the contact. Unwanted stress (stress other than pressure) is applied to the diaphragm 54 due to the unnecessary stress generated in this manner, and the received pressure cannot be detected with high accuracy. Therefore, in order to cancel or reduce such unnecessary stress, the bonding wire 13 is provided.

  Specifically, as shown in FIG. 7, the pressure sensor element 3 is supported by the bonding wire 13 on the side opposite to the bonding wire 15, and the above-described pressure sensor element is utilized by using the tension C of the bonding wire 13. 3 is offset or relaxed (reduced). Further, the posture of the pressure sensor element 3 can be corrected by the bonding wire 13. Thereby, the stress generated in the diaphragm 54 can be reduced, that is, it becomes difficult to apply unintended unnecessary stress (stress other than the received pressure), and the received pressure can be accurately detected.

  In particular, in the present embodiment, since the plurality of bonding wires 13 are provided, the posture control of the pressure sensor element 3 can be accurately performed two-dimensionally. Furthermore, by changing the extending directions of the plurality of bonding wires 13 in plan view, posture control can be performed with higher accuracy. Further, since the wiring portion 249 extends in a direction substantially perpendicular to the side 231b (a direction away from the pressure sensor element 3), the degree of freedom of the length of the bonding wire 13 is increased, and the above-described stress adjustment range is expanded. At the same time, the stress adjustment can be performed with higher accuracy.

  The number of bonding wires 13 is not particularly limited, and can be appropriately changed based on the magnitude of the stress B or the like. That is, the number of bonding wires 13 may be set so that the stress B becomes smaller.

≪Filler≫
As shown in FIG. 1, the filler 11 is filled in an internal space 28 formed in the package 2, thereby covering the pressure sensor element 3 and the IC chip 4 accommodated in the internal space 28. . With this filler 11, the pressure sensor element 3 and the IC chip 4 can be protected (dustproof and waterproof), and external stress that has acted on the electronic device 1 can be reduced. Note that the pressure applied to the electronic device 1 acts on the pressure receiving surface 541 of the pressure sensor element 3 through the opening of the housing 22 and the filler 11.

  Such a filler 11 may be a substance having characteristics that are softer than those of the pressure sensor element 3, the IC chip 4, and the package 2. For example, the filler 11 has a liquid or gel shape, and a specific example is silicone. Oil, fluorine-based oil, silicone gel, or the like can be used. In other words, the filler 11 can be a substance having a Young's modulus smaller than that of the pressure sensor element 3 and the IC chip 4. Further, the viscosity of the filler 11 is not particularly limited, but, for example, the penetration is preferably in the range of 50 or more and 250 or less, and more preferably in the range of 150 or more and 250 or less. Thereby, the filler 11 can be made sufficiently soft, and the pressure applied to the electronic device 1 acts on the pressure receiving surface 541 efficiently.

  The configuration of the electronic device 1 has been described in detail above. Next, a method for manufacturing the electronic device 1 will be described.

  The manufacturing method of the electronic device 1 includes a connection step of connecting the IC chip 4 and the pressure sensor element 3 using a plurality of bonding wires 13 and 15, a measurement step of measuring the electrical characteristics of the pressure sensor element 3, and a measurement Based on the result, if necessary, a stress adjusting step for releasing at least one of the plurality of bonding wires 13 and a housing step for housing the IC chip and the pressure sensor element 3 in the package 2. Contains.

[Connection process]
First, the flexible wiring board 25 and the IC chip 4 are prepared, and the flexible wiring board 25 and the IC chip 4 are connected via bonding wires 14 and 16 as shown in FIG. The connection can be performed using a wire bonding method. Next, the pressure sensor element 3 is prepared, and the flexible wiring board 25 and the pressure sensor element 3 are connected via bonding wires 13 and 15 as shown in FIG. The connection can be performed using a wire bonding method. In this state, it is preferable to provide a large number of bonding wires 13 so as to generate a tension that can cancel the stress generated in the pressure sensor element 3 due to the connection with the bonding wires 15. Further, the tension of at least one bonding wire 13 may be different from the tension of other bonding wires 13. Thereby, it becomes possible to select which bonding wire 13 is to be cut in a stress adjustment step described later, and more appropriate stress adjustment can be performed.

[Measurement process]
Next, the electrical characteristics of the pressure sensor element 3 are measured. Specifically, for example, first, the pressure sensor element 3 is placed in a predetermined (known) atmospheric pressure atmosphere, and the pressure is detected in that state. Then, the detected pressure (output value) is compared with the actual pressure to obtain error information. It is assumed that unnecessary stress is applied to the pressure sensor element 3 as the error increases.

[Stress adjustment process]
Next, based on the error information obtained in the measurement process, as shown in FIG. 10, the connection of at least one of the plurality of bonding wires 13 (two bonding wires 13 ′ and 13 ″ in FIG. 10) is released. As a result, the tension of the bonding wire 13 is reduced, and the stress applied to the pressure sensor element 3 is reduced correspondingly, and the error between the pressure (output value) detected by the pressure sensor element 3 and the actual pressure is reduced. The method for releasing the connection of the bonding wire 13 is not particularly limited, and includes, for example, a method of cutting or removing the bonding wire 13 by a laser. The connection can be released, and the bonding wire 13 can be obtained by using a laser. Therefore, thermal damage to other parts (particularly the pressure sensor element 3 and the IC chip 4) can be reduced.

  Note that the error may be gradually reduced within a predetermined range by repeatedly performing the measurement step and this step. Moreover, when the error information obtained in the measurement process is within the predetermined range from the beginning, this process can be omitted.

[Containment process]
Next, the base 21 and the housing 22 are prepared, and the flexible wiring board 25 is sandwiched between the base 21 and the housing 22, and these are joined to each other. Thereby, the package 2 is obtained, and the pressure sensor element 3 and the IC chip 4 are accommodated in the package 2. Finally, the electronic device 1 is obtained by injecting the filler 11 into the package 2.

According to the manufacturing method as described above, the electronic device 1 having excellent pressure detection characteristics, that is, a small measurement error can be easily manufactured.
The electronic device 1 can also be manufactured by the following manufacturing method.

  Another manufacturing method of the electronic device 1 is a process of connecting the IC chip 4 and the pressure sensor element 3 with a plurality of bonding wires 15 and one bonding wire 13, and measuring the electrical characteristics of the pressure sensor element 3. Based on the measurement process, the measurement result in the measurement process, a stress adjustment process for adding a bonding wire 13 for connecting the IC chip 4 and the pressure sensor element 3 as necessary, the IC chip and the pressure sensor element 3 And a housing step of housing the product in the package 2.

[Connection process]
First, the flexible wiring board 25 and the IC chip 4 are prepared, and the flexible wiring board 25 and the IC chip 4 are connected via bonding wires 14 and 16. Next, the pressure sensor element 3 is prepared, and the flexible wiring board 25 and the pressure sensor element 3 are connected via a plurality of bonding wires 15 and one bonding wire 13 as shown in FIG. Note that the number of bonding wires 13 to be connected in this step is not limited to one and may be two or more.

[Measurement process]
Next, the electrical characteristics of the pressure sensor element 3 are measured. Specifically, for example, first, the pressure sensor element 3 is placed in a predetermined (known) atmospheric pressure atmosphere, and the pressure is detected in that state. Then, the detected pressure (output value) is compared with the actual pressure to obtain error information. It is assumed that unnecessary stress is applied to the pressure sensor element 3 as the error increases.

[Stress adjustment process]
Next, based on the error information obtained in the measurement process, the flexible wiring board 25 and the pressure sensor element 3 are connected by at least one new bonding wire 13 as shown in FIG. That is, the bonding wire 13 is added. As a result, the stress applied to the pressure sensor element 3 is reduced using the tension of the new bonding wire 13, and the error between the pressure (output value) detected by the pressure sensor element 3 and the actual pressure falls within a predetermined range.

  Note that the error may be gradually reduced within a predetermined range by repeatedly performing the measurement step and this step. Moreover, when the error information obtained in the measurement process is within the predetermined range from the beginning, this process can be omitted.

[Containment process]
Next, the base 21 and the housing 22 are prepared, and the flexible wiring board 25 is sandwiched between the base 21 and the housing 22, and these are joined to each other. Thereby, the package 2 is obtained, and the pressure sensor element 3 and the IC chip 4 are accommodated in the package 2. Finally, the electronic device 1 is obtained by injecting the filler 11 into the package 2.

  According to the manufacturing method as described above, the electronic device 1 having excellent pressure detection characteristics, that is, a small measurement error can be easily manufactured.

Second Embodiment
FIG. 13 is a plan view showing an electronic device according to the second embodiment of the present invention.

  Hereinafter, the second embodiment of the electronic device will be described, but the description will focus on differences from the above-described embodiment, and the description of the same matters will be omitted.

  The second embodiment is the same as the first embodiment described above except that the arrangement of the second wires (the arrangement of the stress correction terminals) is different.

  As shown in FIG. 13, in the electronic device 1 of the present embodiment, the stress correction terminal 744 is provided on both the side 231 a side of the pressure sensor element 3 and the side 231 b side of the center portion O. Each stress correcting terminal 744 and the wiring portion 249 are connected by a bonding wire 13. As described above, by providing the stress correction terminals 744 on both sides via the central portion O, stress cancellation or relaxation and posture control as described in the first embodiment can be performed more effectively. .

  Also according to the second embodiment, the same effects as those of the first embodiment described above can be exhibited.

<Third Embodiment>
FIG. 14 is a cross-sectional view showing an electronic device according to the third embodiment of the present invention. 15 is a plan view of the electronic device shown in FIG.

  Hereinafter, the third embodiment of the electronic device will be described. However, the difference from the above-described embodiment will be mainly described, and the description of the same matters will be omitted.

  The third embodiment is the same as the first embodiment described above except that the connection method between the IC chip and the flexible wiring board is different.

  As shown in FIGS. 14 and 15, in the electronic device 1 of the present embodiment, one end portions of the wiring portions 241 and 245 are flying leads 241 a and 245 a protruding into the opening portion 233. The IC chip 4 is fixed to the leading ends of the flying leads 241a and 245a via the conductive fixing member 17, and the connection terminal 42 and the flying leads 241a and 245a are electrically connected via the fixing member 17. Connected. The fixing member 17 is not particularly limited. For example, a metal brazing material such as solder, a metal bump such as a gold bump, a conductive adhesive, or the like can be used.

  Also according to the third embodiment, the same effects as those of the first embodiment described above can be exhibited.

<Fourth embodiment>
FIG. 16 is a cross-sectional view showing an electronic device according to the fourth embodiment of the present invention. 17 is a plan view of the electronic device shown in FIG.

  Hereinafter, the fourth embodiment of the electronic device will be described. However, the difference from the above-described embodiment will be mainly described, and the description of the same matters will be omitted.

  The fourth embodiment is the same as the first embodiment described above except that the connection method between the IC chip and the pressure sensor element is different.

  As shown in FIGS. 16 and 17, in the electronic device 1 of the present embodiment, the pressure sensor element 3 is directly connected to the IC chip via bonding wires 13 and 15. That is, the pressure sensor element 3 is connected to the IC chip 4 without passing through the flexible wiring board 25 (wiring part 241). Thereby, the wiring length can be shortened and the generation of noise can be reduced. In addition, the apparatus can be reduced in size. In the present embodiment, the stress correction terminal 43 corresponding to the stress correction wiring portion 249 is disposed on the upper surface of the IC chip 4 so as to be separated from the connection terminal 42 due to the above configuration. The correction terminal 43 and the stress correction terminal 744 are connected by the bonding wire 13.

  According to the fourth embodiment, the same effect as that of the first embodiment described above can be exhibited.

Next, an electronic apparatus provided with the electronic device of the present invention will be described.
FIG. 18 is a front view showing a navigation system as an example of the electronic apparatus of the present invention.

  As shown in FIG. 18, the navigation system 300 includes a map information (not shown), position information acquisition means from a GPS (Global Positioning System), a gyro sensor, an acceleration sensor, and vehicle speed data. Means, an electronic device 1, and a display unit 301 for displaying predetermined position information or course information.

  According to this navigation system, altitude information can be acquired in addition to the acquired position information. By obtaining altitude information, for example, when traveling on an elevated road that shows approximately the same position as a general road, if you do not have altitude information, you are traveling on an ordinary road or on an elevated road The navigation system was unable to determine whether or not the vehicle was being used, and the general road information was provided to the user as priority information. Therefore, in the navigation system 300 according to the present embodiment, altitude information can be acquired by the electronic device 1, an altitude change due to entering from a general road to an elevated road is detected, and navigation information in the traveling state of the elevated road is obtained. Can be provided to the user.

FIG. 19 is a perspective view showing an altimeter which is an example of the electronic apparatus of the present invention.
As shown in FIG. 19, the altimeter 200 can be worn on the wrist like a wristwatch. In addition, the electronic device 1 is mounted inside the altimeter 200, and the altitude from the sea level of the current location, the atmospheric pressure of the current location, or the like can be displayed on the display unit 201. In addition to altitude and atmospheric pressure, the display unit 201 can display various information such as the current time, the user's heart rate, and weather.

  The electronic apparatus of the present invention is not limited to the above-described ones. For example, a personal computer, a mobile phone, a medical device (for example, an electronic thermometer, a blood pressure monitor, a blood glucose meter, an electrocardiogram measuring device, an ultrasonic diagnostic device, an electronic endoscope, Mirror), various measuring devices, instruments (for example, instruments for vehicles, aircraft, ships), flight simulators, and the like.

Next, a moving body provided with the electronic device of the present invention will be described.
FIG. 20 is a perspective view showing an example of the moving object of the present invention.

  As shown in FIG. 20, the moving body 400 has a vehicle body 401 and four wheels 402, and is configured to rotate the wheels 402 by a power source (engine) (not shown) provided in the vehicle body 401. ing. Such a moving body 400 incorporates a navigation system 300 (electronic device 1).

  As mentioned above, although the electronic device, the manufacturing method of the electronic device, the electronic device, and the moving body of the present invention have been described based on the illustrated embodiments, the present invention is not limited thereto, and the configuration of each part is the same. It can be replaced with any configuration having the above function. Moreover, other arbitrary structures and processes may be added. Moreover, you may combine each embodiment suitably.

  In the above-described embodiment, the pressure sensor unit using the piezoresistive element is described as the pressure sensor unit. However, the pressure sensor unit is not limited to this, and for example, a flap-type vibrator is used. It is also possible to use other MEMS vibrators such as comb-shaped electrodes, and vibration elements such as quartz vibrators.

  In the above-described embodiment, the IC chip is disposed on the lower side of the pressure sensor element (the bottom side of the package). However, these arrangements are not particularly limited. The IC chip may be disposed on the opening side of the first side. In the above-described embodiment, the pressure sensor element is disposed with the diaphragm facing downward, but conversely, the pressure sensor element may be disposed with the diaphragm facing upward.

  In the above-described embodiment, the second wire is not electrically connected to either the pressure sensor element or the IC chip. However, as long as the electric drive of the electronic device is not hindered, the pressure sensor element and the IC chip are not connected. It may be electrically connected to at least one. As such a case, for example, the case where the wiring part 245 also serves as the wiring part 249 can be cited. With such a configuration, the number of wiring portions can be reduced, so that the apparatus can be downsized accordingly.

DESCRIPTION OF SYMBOLS 1 ... Electronic device 11 ... Filler 13, 14, 15, 16 ... Bonding wire 17 ... Fixing member 2 ... Package 21 ... Base 22 ... Housing 23 ... Base material 231 ... Frame part 231a, 231b …… Side 232 …… Strip 233 …… Opening 24 …… Wiring 241 …… Wiring 241a, 245a …… Flying lead 245 …… Wiring 249 …… Wiring 25… Flexible wiring board 26… ... Adhesive layer 28 ... Internal space 3 ... Pressure sensor element 4 ... IC chip 41 ... Semiconductor circuit 42 ... Connection terminal 43 ... Stress correction terminal 5 ... Substrate 51 ... Semiconductor substrate 511 ... No. 1 of Si layer 512 ...... SiO ₂ layer 513 ...... second Si layer 52 ...... first insulating film 53 ...... second insulating film 54 ...... diaphragm 541 ...... pressure receiving surface 55 ...... recess 6 ... Pressure sensor part 60 ... Bridge circuit 61, 62, 63, 64 ... Piezoresistive element 611, 621, 631, 641 ... Piezoresistive part 632, 642 ... Connection part 613, 623, 633, 643 ... Wiring 7: Element peripheral structure 71, 73: Interlayer insulating film 72, 74 ... Wiring layer 741 ... Cover layer 742 ... Pore 743 ... Connection terminal 744 ... Stress correction terminal 75 ... Surface protective film 76 …… Sealing layer 8 …… Cavity portion 200 …… Altitude meter 201 …… Display portion 300 …… Navigation system 301 …… Display portion 400 …… Moving body 401 …… Car body 402 …… Wheel O …… Center portion

Claims (15)

A wiring board;
Electronic components,
A first wire that electrically connects the wiring board and the electronic component;
An electronic device comprising: a second wire connecting the wiring board and the electronic component so as to adjust a stress generated in the electronic component by the first wire. A plurality of the first wires;
The electronic device according to claim 1, wherein the arrangement of the first wires is asymmetric with respect to a central portion of the electronic component in a plan view.   The electronic device according to claim 1, wherein the second wire is not electrically connected to the wiring board.   The electronic device according to claim 1, wherein the second wire is not electrically connected to the electronic component.   The electronic device according to claim 1, wherein a circuit is provided on the wiring board.   The electronic device according to claim 1, wherein the electronic component is a pressure sensor element having a diaphragm.   The electronic device according to claim 1, wherein the first wire and the second wire contain the same metal material as a main material.   The electronic device according to claim 1, wherein the wiring board and the electronic component are directly connected by the first wire and the second wire. Connecting the wiring board and the electronic component with a plurality of first wires and a plurality of second wires;
Measuring the electronic component;
A step of releasing at least one of the plurality of connections by the second wires based on a measurement result in the measuring step, if necessary. Production method.   The method for manufacturing an electronic device according to claim 9, wherein in the measuring step, electrical characteristics of the electronic component are measured.   The method of manufacturing an electronic device according to claim 9, wherein in the releasing step, the second wire is cut.   The method for manufacturing an electronic device according to claim 9, wherein, in the releasing step, the second wire is cut or removed using a laser. Connecting the wiring board and the electronic component with a plurality of first wires and second wires;
Measuring the electronic component;
And a step of adding the second wire for connecting the wiring board and the electronic component, if necessary, based on a measurement result in the measuring step.   An electronic apparatus comprising the electronic device according to claim 1.   A moving body comprising the electronic device according to claim 1.

Images