Patent Abstract:
An inertial sensor, comprises a detection element detecting an amount of a physical quantity in a detection axis direction, a plurality of support members having flexibility and supporting nearly a center of the detection element, and a package substrate housing the detection element and the plurality of support members. In a case when an X-axis is defined as an extending direction of the plurality of support members, a Y-axis is perpendicular to the X-axis in a plane including the detection element, and a Z-axis is perpendicular to the X-axis and the Y-axis, one of load components in a direction of the Y-axis of the detection member applied to the plurality of support members is nearly equal to other among the plurality of support members, and one of load components in a direction of the Z-axis is nearly equal to the other among the plurality of support members.

Full Description:
This is a Continuation of application Ser. No. 11/878,883 filed Jul. 27, 2007, now U.S. Pat. No. 7,886,596 which claims the benefit of Japanese Patent Application No. 2006-216505 filed Aug. 9, 2006; Japanese Patent Application No. 2006-249404 filed Sep. 14, 2006; and Japanese Patent Application No. 2007-119281 filed Apr. 27, 2007. The disclosures o the prior applications are hereby incorporated by reference herein in their entirety. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present invention relates to an inertial sensor such as an acceleration sensor and a gyro sensor and a method for manufacturing it, and is particularly preferred for in-vehicle navigation devices. 
     2. Related Art 
     In-car navigation devices are popularly spread out. When detecting a current position of a vehicle via such device, two methods are combined: a method for positioning a vehicle by using a so-called global positioning system (GPS), and a method for autonomously positioning the moving direction and distance of a vehicle. In order to autonomously position the moving direction and distance of a vehicle, an inertial sensor such as a gyro sensor (an angular velocity sensor) for detecting acceleration or angular velocity yielded by a moving vehicle are mounted in car navigation devices. 
     When acceleration or angular velocity is detected by using an inertial sensor, the detection axis of the sensor needs to be coincided with a direction to be detected. For example, the detection axis of a gyro sensor needs to be installed upward along the vertical direction. 
     In recent years, downsizing in-car navigation devices have been advanced. A casing main body (hereinafter, referred to as “an navigation body”), has been developed as to be installed into a center console between a driver seat and a passenger seat, though it was conventionally installed under a seat or inside a trunk. 
       FIGS. 15A and 15B  show a navigation body installed in a center console.  FIG. 15A  is the whole perspective view.  FIG. 15B  shows a gyro sensor mounted in the navigation body. 
     When a navigation body  100  is installed in a center console  102  as shown in  FIG. 15A , the surface of a display  101  and an operation panel (not shown) are preferably directed to a driver&#39;s viewing direction because of his/her visibility of the display  101  and operability of the operation panel. That is, the navigation body  100  is preferably installed tilted obliquely upward from the horizontal direction in the center console  102 . When the navigation body  100  is installed tilted obliquely upward in the center console  102 , however, as shown in  FIG. 15B , the detection axis G of a gyro sensor  104  is slanted by angle (a tilt angle) θ from the vertical direction V. Here, the gyro sensor  104  is mounted on a printed board  103  in the navigation body  100  that is installed with also tilted by the angle θ. Due to this tilt, errors occur in angular velocity detected by the gyro sensor  104 . 
     In ordinal car navigation devices, such detection errors of the gyro sensor  104  due to the installation angle of the navigation body  100  are corrected by software arithmetic processing. The software arithmetic processing, however, is insufficient. For example, the software arithmetic processing cannot correct detection errors when the tilt angle θ of the navigation body  100  is 30° or more. 
     In order to avoid such insufficiency, an inertial sensor is required that can correctly perform a detection even when a car navigation device is installed tilted. Various kinds of sensors are proposed to satisfy the requirement. 
     For example, a first example of related art discloses an angular velocity sensor in which a detection axis is tilted by an angular velocity detection element inside the sensor being slanted from a holder without changing the shape of or mounting method of the sensor. 
     Further, a second example of related art discloses a sensor device provided with a detection element detecting a direction and magnitude of a physical quantity having a constant directional property and a fixture for fixing and supporting the detection element. In the device, the detection element is fixed to the fixture and tilted by a predetermined reduced angle in a reducing direction. The reducing direction reduces an predicted angular difference between the direction of the detection axis, serving as the reference for detecting the magnitude and the direction of the physical quantity, and a direction of the physical quantity actually applied to the detection element during detecting. 
     A third example of related art discloses a supporting structure in which the angle of a vibrator in a package is set by a support connecting the vibrator to a support substrate and an adhesive bonding the support substrate and a package substrate so as to direct the detection axis of the vibrator in a desired direction. 
     Here, WO03/100350 is the first example, JP-A-2003-227844 is the second example, and JP-A-2005-249428 is the third example of related art. 
     The sensors disclosed in the first and second examples, however, may deteriorate detection performance due to acoustic leakages or unwanted vibration modes of the quartz crystal resonator yielded from a fixture since the quartz crystal resonator serving as a detection element is directly fixed to the fixture. 
     In addition, the sensors disclosed in the first and second examples, a specialized tool is required for every fixing angle since the detection element in itself needs to be fixed tilted. As a result, production costs soar. The reason for requiring the specialized tool is as follows. In each sensor, the detection element is irradiated with a laser to adjust the sensor after fixing the detection element to the fixture. Thus, one of focal points of the laser differs from others every one of fixing angles when changing the fixing angle, resulting in that the same tool is not shared. 
     Further, in the second example, a slit is formed in a detection element in itself for fixing it tilted. This process causes a high cost of a detection element, increasing total production costs. 
     Furthermore, in the first and second examples the angle of a detection axis cannot be set to any angle when a sensor is mounted on a mount board since a detection element is set tilted within a sensor. 
     Further, a support (bonding wire) connecting a vibrating element (vibrator) to a support substrate shown in the third example significantly affects occurrence of acoustic leakages and unwanted vibration modes from the vibrating element, sometimes deteriorating detection performance of the sensor. In addition, changing the angle with using the adhesive causes large variations in production, resulting in a setting angle being inaccurate. 
     Further directly fixing an element to a fixture in the first and second examples also causes occurrence of acoustic leakages and unwanted vibration modes from the vibrating element, resulting in a setting angle being inaccurate. 
     Taking the above into consideration, the inventors pay attention to a method that a sensor device in which a sensor element is fixed by a conventional bonding method is bonded to a lead frame and molded. The method can suppress the occurrence of acoustic leakages and unwanted vibration modes since the sensor element is fixed by the conventional bonding method, control a setting angle corresponding to a detection axis, by which the sensor responds to movements, with the shape of the lead frame, and further secure mechanical strength as molded. 
     However, in the method, the sensor device including the sensor is tilted with respect to a mount surface corresponding to the detection axis by which the sensor responds to movements, by controlling the shape of the lead frame. Thus, when a sensor device is formed by using a related art molding method in which the outline of the molded one follows the outline of the sensor device, the outline of the sensor device is not parallel with the mount surface. This outline may worsen workability in mounting processes. 
     SUMMARY 
     An advantage of the invention is to provide an inertial sensor that can set a detection axis at a predetermined angle without deteriorating detection performance of a detection element. 
     Another advantage of the invention is to provide a method for manufacturing an inertial sensor device that can accurately set the detection axis of the sensor when the device is fixed on a mount surface having a predetermined tilt angle, and can set a predetermined angle that the detection axis of the sensor makes with respect to a bottom surface and an upper surface of a molded package, improving workability. 
     An inertial sensor according to a first aspect of the invention includes a detection element detecting an amount of a physical quantity in a detection axis direction, a plurality of support members having flexibility and supporting nearly a center of the detection element, and a package substrate housing the detection element and the plurality of support members. In a case when an X-axis is defined as an extending direction of the plurality of support members, a Y-axis is perpendicular to the X-axis in a plane including the detection element, and a Z-axis is perpendicular to the X-axis and the Y-axis, one of load components in a direction of the Y-axis of the detection member applied to the plurality of support members is nearly equal to other among the plurality of support members, and one of load components in a direction of the Z-axis is nearly equal to the other among the plurality of support members. 
     This structure can render the setting condition of mechanical resonance frequency of each support member robust to the change of force caused by acceleration since an effect due to the acceleration is equally applied to each support member. That is, the following trouble can be prevented. The resonance frequency of the support member varies to an unexpected value. In addition, the resulting frequency approaches near the driven vibration of the inertial sensor during a process in which the driven frequency of the inertial sensor varies with a temperature change. The driven vibration frequency of the inertial sensor is coupled with (attracted to) the resonance frequency of the support member. As a result, the output signal of the inertial sensor jumps. 
     In this case, the detection element may have a detection axis that detects an angular velocity and coincides with the direction of the Z-axis that makes an angle of θ with respect to a vertical direction, and a resulting load combined by the component in the direction of the Y-axis of the load and the component in the direction of the Z-axis of the load may be at least a load component based on gravity acceleration. 
     This structure can render the setting condition of mechanical resonance frequency of each support member robust to the change of force caused by acceleration since an effect due to the acceleration is equally applied to each support member even when the inertial sensor is set tilted. That is, the following trouble can be prevented. The resonance frequency of the support member varies to an unexpected value. In addition, the resulting frequency approaches near the driven vibration of the inertial sensor during a process in which the driven frequency of the inertial sensor varies with a temperature change. The driven vibration frequency of the inertial sensor is coupled with (attracted to) the resonance frequency of the support member. As a result, the output signal of the inertial sensor jumps. 
     In addition, the driven frequency of the inertial sensor can be inspected while the inertial sensor is tilted. As a result, the inspection process can be simplified. 
     Further, this structure has an advantage in that the resonance frequency of the support member is robust to acceleration of a vehicle during its movement. 
     In this case, the Z-axis may make the angle of θ with respect to the vertical direction by tilting the inertial sensor around a longitudinal direction of the sensor. 
     This structure can reduce the height of an inertial sensor device when the inertial sensor is built into an inertial sensor device as the sensor is tilted. 
     An inertial sensor device according to a second aspect of the invention includes the inertial sensor of the first aspect of the invention, a plurality of lead terminals electrically coupled to the inertial sensor, and a molded package including the inertial sensor. 
     This structure can render the setting condition of mechanical resonance frequency of each support member robust to the change of force caused by acceleration since an effect due to the acceleration is equally applied to each support member. That is, the following trouble can be prevented. The resonance frequency of the support member varies to an unexpected value. In addition, the resulting frequency approaches near the driven vibration of the inertial sensor during a process in which the driven frequency of the inertial sensor varies with a temperature change. The driven vibration frequency of the inertial sensor is coupled with (attracted to) the resonance frequency of the support member. As a result, the output signal of the inertial sensor jumps. 
     In this case, the molded package may include a first lead terminal extending toward a direction of a bottom surface of the molded package from a first part of the molded package, and a second lead terminal longer than the first lead terminal, the second lead terminal extending toward the direction of the bottom surface of the molded package from a second part facing the first part. The second lead terminal may include a plurality of bending parts facing the molded package. 
     This structure can prevent the inertial sensor from being floated by a coated solder along the second lead terminal when the inertial sensor is mounted to a mount board. 
     A method for manufacturing an inertial sensor device according to a third aspect of the invention is the method that molds a lead frame and a sensor device with resin. The lead frame includes a plurality of lead terminals electrically connecting a mount board. The sensor device includes a sensor that responds to a movement with respect to a detection axis and is directed by a shape of the lead frame at a setting angle. The method includes: bonding the sensor device to the lead frame; overlapping a lower die having a first surface in which a concave part is formed and an upper die having a second surface in which a second concave part is formed so that the first surface and the second surface meet each other with the lead frame interposed between the lower die and the upper die to house the sensor device in a cavity formed by the first concave part and the second concave part, after the bonding; and injecting resin into the cavity. The first concave part has a first bottom surface and the second concave part has a second bottom part, and after the overlapping, the first bottom surface and the second bottom surface are tilted with respect to a main surface of the lead frame and are in parallel with each other. 
     This method can form a molded package that has an outline in parallel with the mount board and includes the sensor device adjusted to the setting angle with respect to the mount board corresponding to the detection axis responding to the movement. As a result, the inertial sensor device can be manufactured that has improved workability in mounting the device. 
     In the method, the first bottom surface and the second bottom surface may be tilted by the setting angle with respect to the main surface of the lead frame. 
     Using the dies can form the molded package of the inertial sensor device so that the bottom surface of the sensor device makes an angle with respect to the bottom surface of the inertial sensor device and the normal line of the bottom surface of the inertial sensor device makes a predetermined angle with respect to the detection axis. 
     As a result, the inertial sensor device can be manufactured that allows the detection axis of the sensor to be accurately set even if the inertial sensor device is fixed to a tilted surface by setting an angle that the normal line of the bottom surface of the inertial sensor device makes with respect to the detection axis equal to an angle that the normal line of the surface of the tilted mount board on which the inertial sensor device is mounted makes with respect to the vertical direction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIGS. 1A and 1B  are schematic views illustrating the structure of a gyro sensor device according to a first embodiment of the invention. 
         FIG. 1A  is the top view. 
         FIG. 1B  is the side view. 
         FIG. 2A  shows a mounting example of the gyro sensor device of the first embodiment. 
         FIG. 2B  shows a mounting example of a gyro sensor device. 
         FIGS. 3A to 3D  are schematic views illustrating a lead terminal unit used in the gyro sensor device of the first embodiment. 
         FIG. 4  is a flowchart illustrating manufacturing steps of the gyro sensor device. 
         FIG. 5  is a schematic view illustrating the structure of a gyro sensor device according to a second embodiment of the invention. 
         FIG. 6  is a schematic view illustrating a tool for wire bonding according to the second embodiment. 
         FIG. 7  is a schematic view illustrating the structure of a gyro sensor device according to a third embodiment of the invention. 
         FIG. 8  is a sectional view illustrating an internal structure of a gyro sensor  10 . 
         FIGS. 9A to 9C  are schematic views illustrating the structure of a support substrate included in the gyro sensor  10 . 
         FIG. 10A  is a plan view schematically illustrating a quartz crystal resonator element  11 . 
         FIG. 10B  is a plan view illustrating a vibration of the detection vibration mode of the quartz crystal resonator element  11 . 
         FIG. 11A  is a plan view illustrating wires  13  and a tilt direction where the present invention is not applied. 
         FIG. 11B  is a side view illustrating a gyro sensor device, in which the quartz crystal resonator element  11  is placed on the wires  13  shown in  FIG. 11A , installed tilted. 
         FIG. 11C  shows the relationship between the resonance frequency of the wire  13  of the gyro sensor device shown in  FIG. 11B  and the resonance frequency of the quartz crystal resonator element  11 . 
         FIG. 12A  is a plan view illustrating the wires  13  and a tilt direction where the present invention is applied. 
         FIG. 12B  is a side view illustrating a gyro sensor device, in which the quartz crystal resonator element  11  is placed on the wires  13  shown in  FIG. 12A , installed tilted. 
         FIG. 12C  shows the relationship between the resonance frequency of the wire  13  of the gyro sensor device shown in  FIG. 12B  and the resonance frequency of the quartz crystal resonator element  11 . 
         FIG. 13  is a schematic view illustrating the structure of a lower die of a molding die. 
         FIG. 14  is a schematic view illustrating the whole structure of the molding die. 
         FIGS. 15A and 15B  show a navigation body installed in a center console. 
         FIG. 15A  is the whole perspective view. 
         FIG. 15B  shows a gyro sensor mounted in the navigation body. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Embodiments of the present invention will now be described below. 
     In the embodiments, a gyro sensor will be described as an example of an inertial sensor of the invention. 
       FIGS. 1A and 1B  are schematic views illustrating the structure of a gyro sensor device of a first embodiment of the invention.  FIG. 1A  is the top view.  FIG. 1B  is the side view. 
     In a gyro sensor device  1  shown in  FIGS. 1A and 1B , a gyro sensor  10  is sealed with a resin part  2 , formed by a molding compound such as resin, so that the angular velocity detection axis G (detection axis G) of the gyro sensor  10  is tilted by an angle θ with respect to the perpendicular line V of the upper surface of the gyro sensor device  1 . From both the long sides of the resin part  2 , a plurality of lead terminals extends outside. 
     Here, the upper surface and a mounting side surface (the other surface opposite to the upper surface) of the gyro sensor device  1  are in parallel with each other. The lead terminals  3  are electrically connected to the gyro sensor  10  inside the resin part  2 . The lead terminals  3  exposed from the resin part  2  at a position close to its bottom surface are bent inside at bending parts  4   a  and  4   b  to form electrode terminals on the bottom surface of the resin part  2 . In contrast, other lead terminals  3  exposed from the resin part  2  at a position far from its bottom surface also bent to form electrode terminals on the bottom surface of the resin part  2 . In this case, they are bent inside at bending parts  4   c,    4   d,  and  4   e  since the length of a lead part of each lead terminal  3  exposed from the resin part  2  is long. 
       FIG. 2A  shows a mounting example of the above gyro sensor device of the first embodiment. As shown in  FIG. 2A , by connecting each lead terminal  3  of the gyro sensor device  1  of the embodiment to a pattern electrode  52  with a solder  53 , the gyro sensor device  1  can be mounted so that its detection axis G is tilted by the angle θ with respect to the perpendicular line (the vertical direction) of the mount surface of a mount board  51 . 
     The reason why the lead terminal  3  exposed from the position far from the bottom surface of the gyro sensor device  1  is provided with the bending parts  4   c,    4   d , and  4   e  is as follows. 
     For example, as shown in  FIG. 2B , if the bending part  4   d  is not formed between the bending parts  4   c  and  4   e  of the lead terminal  3 , the amount of the solder  53  coated on it is larger than that of the lead terminal  3  having a short lead part from the bending parts  4   a  to  4   b.  This imbalance causes a large difference in surface tension of the solder  53  at both sides, and the lead terminal having the short lead part may float from the mount surface  51 . That is, errors may occur in a tilt angle since the gyro sensor device  1  is fixed slanted. 
     Therefore, in the gyro sensor device  1 , the bending parts  4   c,    4   d,  and  4   e  are formed in the lead terminal  3  having a long lead part from the bending parts  4   c  to  4   e  to limit the solder amount coated along it. This structure can limit the solder amount coated along the lead terminal having the long lead part. As a result, the occurrence of errors in the tilt angle of the gyro sensor device  1  fixed to the mount board  51 . 
     Particularly, setting the height position of the lead terminal having the long lead part equal to that of the lead terminal having the short lead part is more preferable since the solder amount coated along each lead terminal  3  makes equal. 
     In addition, even if the solder coats the lead terminal  3  having the long lead part beyond the bending part  4   d  upward, the surface of the lead terminal  3  coated by the solder does not face any pattern electrode  52 . Thus, surface tension causing the gyro sensor device  1  to be tilted does not occur in this case. 
     Here, the gyro sensor device  1  has the upper surface and the mounting side surface that are in parallel with each other. This structure allows the gyro sensor device  1  to be moved in the vertical direction to the mount board  51  and to be mounted on it after suctioning the upper surface of the gyro sensor device  1  by using a parts-mounting device. 
     In this case, the gyro sensor device  1  is pushed to the mount board  51  while a force is equally applied to the lead terminals  3  or uniformly applied to the bottom surface of the resin part  2  upon mounting it to the mount board  51 . As a result, the parallelism between the mount surface of the mount board  51  and the upper surface of the gyro sensor device  1  is kept high. That is, the gyro sensor device  1  is mounted to the mount board  51  without errors in the angle θ that the detection axis G makes with respect to the perpendicular line of the mount surface of the mount board  51 . 
     In the embodiment, the gyro sensor  10  is tilted around its longitudinal direction so as to provide an angle that the Z-axis makes with respect to the vertical direction to be θ. This structure can reduce the height of the device when the gyro sensor  10  is built into the gyro sensor device  1 . 
     Next, a method for bonding the lead terminals and the gyro sensor in the gyro sensor device of the embodiment will be described. 
       FIG. 3A  shows the structure of a lead terminal unit used in the gyro sensor device  1  of the embodiment.  FIG. 3B  is a top view illustrating a state in which the gyro sensor  10  is bonded to the lead terminal unit.  FIG. 3C  is a backside view illustrating the state in which the gyro sensor  10  is bonded to the lead terminal unit.  FIG. 3D  illustrates a setback when the gyro sensor  10  is bonded to the lead terminals  3 . 
     As shown in  FIG. 3A , the lead terminal unit  61 , used in the gyro sensor device  1  of the embodiment, includes the plurality of lead terminals  3  and a die pad  5 . In the embodiment, the lead terminals  3  and the frame  63  are connected with suspending leads  62  to prevent the lead terminals  3  from being bent when the gyro sensor  10  and the lead terminals  3  are connected. 
     The die pad  5  provided on the upper surface of the lead terminal unit  61  and the gyro sensor  10  are mechanically connected with an adhesive interposed therebetween, for example. They may be electrically connected by using a conductive adhesive as the adhesive. In addition, each lead terminal  3  of the lead terminal unit  61  is electrically connected to respective electrodes  8  provided on the bottom surface of the gyro sensor  10  with a bonding wire or a conductive adhesive or the like. 
     Here, if the suspending leads  62  for the lead terminals  3  are not provided, the gyro sensor  10  sometimes rotates around the die pad as an axis due to the bending of the lead terminals  3  as shown in  FIG. 3D  when the gyro sensor  10  is mounted to the lead terminal unit  61 . As a result, the gyro sensor  10  cannot be mounted to the lead terminals  3  with high accuracy, possibly errors occurring in the tilt angle of the gyro sensor  10 . In contrast, the gyro sensor device  1  of the embodiment can suppress the rotation of the gyro sensor  10  since the bending of the lead terminals  3  are suppressed by fixing the lead terminals  3  with the suspending leads  62 . 
     As a result, the accuracy of the tilt angle of the gyro sensor device  1  of the embodiment can be enhanced. As shown in  FIG. 3A , the lead terminal unit  61  includes three suspending terminals  62  fixing the distal parts of the lead terminals  3 . The suspending lead  62  for fixing the distal part of the lead terminal  3  may be diagonally provided at least two positions with respect to the die pad  5 . This arrangement can suppress the rotation of the gyro sensor  10  in the diagonal direction. Here, the suspending leads  62  are cut off after the resin part  2  is formed. 
     Next, a method of manufacturing the gyro sensor device of the first embodiment will be described. 
       FIG. 4  is a flowchart illustrating manufacturing steps of the gyro sensor device. 
     First, in step S 1 , an adhesive (nonconductive adhesive or epoxy based adhesive) is applied to the die pad  5  or the gyro sensor  10 , and then the gyro sensor  10  is placed on the die pad  5  to adhere. 
     Next, in step S 2 , a wire bonding is performed by forming wires between the lead terminals  3  and the electrode terminals  8  provided on the bottom surface of the gyro sensor  10  by a wire bonding method. 
     Next, in step S 3 , molding is performed in which the gyro sensor  10  is molded with a resin. The molding is performed by a so-called transfer molding method, in which the lead terminals  3  are set and sandwiched between an upper and lower dies each of which have a cavity so that the gyro sensor  10  is housed in the cavity, and then the cavity is filled with the resin. In this case, the lead terminals  3  exposed from the die are extended to have an original shape. In addition, a number of patterns of the lead terminals  3  are formed so as to mount a plurality of gyro sensors  10 . 
     In this step, the upper and lower dies are heated and kept at a predetermined temperature in accordance with the characteristics of the resin, and then the lead terminals  3 , on which the gyro sensor  10  is bonded with wires, are positioned and placed on the lower die by using the positioning pins of the lower die as a positioning reference, for example. Next, a resin tablet is put into a plunger pot of the lower die. Then, the upper die is placed on the lower die so as to sandwich the lead terminals  3  therebetween. Subsequently, the upper and lower dies are uniformly clamped by applying a predetermined pressure. As a result, the gyro sensor  10  is housed inside each cavity of the upper and lower dies. 
     Next, the resin tablet inside the plunger pot is pre-heated at a predetermined temperature to be melted. The melted resin is injected into the cavity from the gates of the upper and lower dies by operating the plunger with a predetermined phase, velocity, and temperature. After the cavity is filled with the melted resin, a fixed time is kept to form the resin. After the resin is formed, the upper die is removed from the lower die by releasing the clamping of the dies. Then, a remaining cull produced by the resin overflowing around the cavity is removed. Next, the lead terminals  3  with molded resin are taken out from the lower die, and then dried in an oven at a predetermined temperature for a given period. 
     Next, in step S 4 , the ends of the lead terminals  3  and the suspending leads between the leads are cut off by stamping or the like so as to make the molded part as an individual piece. Subsequently, in step S 5 , a terminal plating is performed in which the lead terminals exposed from the molded part are plated with bonding metal such as tin (Sn) and solder. Then, the bending parts  4   a  and  4   c  are bent into a predetermined shape by fixing the lead terminals between the bending part  4   a  and the resin part  2  as well as the bending part  4   c  and the resin part  2 . Next, in step S 6 , the bending parts  4   b  and  4   d  are bent by fixing the lead terminals between the bending part  4   b  and the resin part  2  as well as the bending part  4   d  and the resin part  2 , achieving the gyro sensor device  1 . 
     The terminal plating may be carried out before or after the lead terminals and suspending leads are cut off. 
     Finally, in step S 7 , necessary inspection such as characteristics inspection and outer appearance inspection is carried out, ending the manufacturing steps of the gyro sensor device  1  of the embodiment. 
     As described above, the method for manufacturing the gyro sensor device  1  of the embodiment, in which the detection axis of the gyro sensor  10  and the upper surface of the resin part  2  are set at a desired angle, with high productivity can be provided. 
     Next, a die used for molding in the above method for manufacturing the gyro sensor device  1  will be described with reference to the drawings. 
       FIG. 13  is a plan view illustrating a lower die  110 A, which constitutes a molding die with an upper die.  FIG. 14  is a sectional view illustrating a whole structure of a molding die  110 , the sectional view being taken along the line a-a in  FIG. 13  where an upper die  110 B is set to the lower die  110 A with the lead terminals  3  interposed therebetween. 
     The molding die  110  includes the upper die  110 B and the lower die  110 A. In order to easily explain the structure of a resin injection path or the like in the molding die  110 , the structure of the lower die  110 A will be described with reference to  FIG. 13 . 
     The lower die  110 A includes a lower die body  120 , made of metal or the like, in which a plurality of concave parts (cavities) are formed and each cavity is connected in series by communicating with a linking path (e.g. gate), also a concave part. 
     The lower die  110 A is provided with a plunger pot  115 , in which a plunger (not shown) is set, inside a concave part formed in the lower die body  120  in a cylindrical shape. The plunger pot  115  has an opening at a part of its sidewall. From the opening, a runner  116 A having a groove shape extends and connects to a cavity  111 A as a first cavity, a concave part having a rectangular parallelepiped shape. Near a side, opposite to the part connecting the plunger pot  115 , of the cavity  111 A, a cavity  112  as a second cavity is disposed. The cavities  111 A and  112  are connected by communicating with a gate  113 A having a grove shape. In addition, from a side, opposite to the part connecting the cavity  111 A, of the cavity  112 , a gate  114  extends. The gate  114  is communicated and connected with the next cavity in the same manner, but this is not shown in  FIG. 13 . As described above, the plunger pot  115 , the cavity  111 A, and the cavity  112  are connected in series by communicating with the runner  116 A, the gate  113 A, and the gate  114 , respectively. Likewise, the cavity  112  afterward, the necessary number of cavities are connected in series by communicating with the necessary number of gates. 
     Here, a rectangular area shown by the two-dot chain line in the  FIG. 13  illustrates a lead frame placing position  3   a  upon resin molding. 
     In contrast, the upper die  110 B is provided with a plunger pot, a plurality of cavities, and a plurality of runners and gates both of which communicate with the plunger pot and the cavities on the surface meeting the lower die  110 A. They are formed in the same shape openings at the same positions corresponding to those in the lower die  110 A. Upon overlapping and fixing the upper die  110 B and the lower die  110 A, the plunger pot  115 , a space of a container shape, cavities, runners, and gates are formed. The runners and gates connect and communicate with the plunger pot  115  and cavities in series for serving as a communication path of resin. 
     Next, with reference to the  FIG. 14 , the molding die  110  including the upper die  110 B and the lower die  110 A will be described in a condition where the lead terminals  3 , on which the gyro sensor  10  serving as a sensor device is mounted, are molded. Particularly, the cross sectional shape of the cavity of the molding die  110  will be mainly described in details. 
     As shown in  FIG. 14 , a concave bottom part  161 A of the cavity  111 A, the concave part formed in the lower die body  120  of the lower die  110 A, is formed so as to be tilted by the angle θ with respect to a parallel line  170 , parallel with the lead terminal  3  when the lead terminals  3  are placed on the lower die  110 A. The bottom surface of the gyro sensor device  1  is formed corresponding to the concave bottom part  161 A. Therefore, the gyro sensor device  1  is formed in which the relation between the normal line of the gyro sensor device  1  achieved by molding with the lower die  110 A and the detection axis G of the gyro sensor  10  is set as a desired angle θ. 
     Likewise, a concave bottom part  161 B of the cavity  111 B, the concave part formed in an upper die body  130  of the upper die  110 B shown in  FIG. 14 , is formed so as to be tilted by the angle θ with respect to a parallel line  270 , parallel with the lead terminal  3  when the upper die  110 B is overlapped and fixed on the lower die  110 A on which the lead terminal  3  is placed. The upper surface of the gyro sensor device  1  is formed corresponding to the concave bottom part  161 B. Therefore, the gyro sensor device  1  is formed in which the relation between the normal line of the upper surface of the gyro sensor device  1  achieved by molding with the upper die  110 B and the detection axis G of the gyro sensor  10  is set as the desired angle θ. 
     Upon fixing (clamping) the lower die  110 A and the upper die  110 B with the lead terminal  3  on which the gyro sensor  10  is mounted interposed therebetween, a cavity for molding the sensor device  10  is formed by the cavity  111 A of the lower die  110 A and the cavity  111 B of the upper die  110 B. 
     In addition, a runner is formed by the runner  116 A of the lower die  110 A and the runner  116 B of the upper die  110 B. The runner serves as an injection path of melted resin when the resin is injected into the cavity from the plunger pot (not shown). 
     Further, a gate is formed by the gate  113 A of the lower die  110 A and the gate  113 B of the upper die  110 B. The gate serves as an injection path of the resin from the cavity to the next cavity. 
     In the embodiment, the runner  116 B and the gate  113 B of the upper die  110 B are formed larger than the runner  116 A and the gate  113 A of the lower die  110 A in the thickness direction, respectively. As a result, resin flows in the upper die  110 B stronger than in the lower die  110 A. This structure prevents a bonding part such as bonding wires and gold balls of the gyro sensor  10  from being strongly hit by the melted resin when the resin is injected. The structure is not limited to this. The runners and gates may be disposed only in the upper die  110 B for skirting the bonding part of the gyro sensor  10 . 
     Here, the sidewall of the cavities  111 A and  111 B are formed inward so as to be perpendicular or make an acute angle with respect to the surface contacting the lead terminals  3 . 
     As described above, in the method for manufacturing the gyro sensor device  1  of the embodiment, the cavity  111 A having the concave bottom part  161 A is formed in the lower die body  120  of the lower die  110 A. The concave bottom part  161 A is formed so as to be tilted by the angle θ with respect to the parallel line  170 , parallel with the lead terminal  3  when the lead terminal  3  is placed on the lower die  110 A. In addition, the cavity  111 B is formed in the upper die body  130  of the upper die  110 B. The cavity  111 B is the concave part formed so as to be tilted by the angle θ with respect to the parallel line  270 , parallel with the lead terminal  3  when the upper die  110 B is overlapped and fixed on the lower die  110 A on which the lead terminal  3  is placed. Then, the lower die  110 A and the upper die  110 B are fixed by sandwiching the lead terminals  3  therebetween so that the gyro sensor  10  is housed in the cavity  111 A and the cavity  110 B. Subsequently, melted molding resin is injected into the cavities  111 A and  111 B to form the gyro sensor device  1 . 
     The method can manufacture the molded package (resin part  2 ) having the bottom surface formed corresponding to the concave bottom part  161 A of the lower die  110 A, and the upper surface formed corresponding to the concave bottom part  161 B of the upper die  110 B. As a result, a gyro sensor device can be provided in which the detection axis G of a sensor makes a desired angle with respect to the bottom surface of the gyro sensor device. The gyro sensor device includes the sensor responding to a movement with respect to the given detection axis G, the gyro sensor  10  housing the sensor, the lead part to make electrically conduction between the terminal of the gyro sensor  10  and a mount board, and a molded package to fix the gyro sensor  10 . 
     In addition, the bottom surface and the upper surface of the gyro sensor device can be formed in parallel with each other. The bottom surface and the upper surface of the gyro sensor device make a desired angle with respect to the detection axis G of the gyro sensor. Thus, the gyro sensor device can be picked up in the same manner of typical chip-type electronic parts by a chip mounter, for example, when the gyro sensor is mounted to a mount board or the like. Further, typical part trays and hoop shaped packaging materials (taping materials) can be used for packaging the gyro sensor device without preparing trays and hoop shaped packaging materials having a special shape. As a result, a gyro sensor device can be manufactured that can be mounted with high productivity. 
     In the embodiment, the runner  116 B and the gate  113 B of the upper die  110 B are formed larger than the runner  116 A and the gate  113 A of the lower die  110 A in the thickness direction, respectively. 
     Because of the structure, melted resin flows in the upper die  110 B stronger than in the lower die  110 A when the resin is injected into each cavity. Thus, stress applied to the bonding part such as bonding wires and gold balls of the gyro sensor  10  placed in the lower die  110 A by the resin can be reduced. As a result, the occurrence of bonding wire breakage and open defects in bonding parts can be suppressed. 
     In addition, in the embodiment, the sidewalls of the cavity  111 A of the lower die  110 A and the cavity  111 B of the upper die  110 B are formed inward so as to be perpendicular or make an acute angle with respect to the surface contacting the lead terminals  3 . This structure enhances removability in releasing the lower die  110 A and the upper die  110 B from the clamping state, enabling the workability to be improved. 
       FIG. 5  is a schematic view illustrating the structure of a gyro sensor device according to a second embodiment of the invention. 
     In a gyro sensor device  20  shown in  FIG. 5 , the gyro sensor  10  is sealed with the resin part  2  so that the detection axis G of the gyro sensor  10  is tilted by the angle θ with respect to the perpendicular line of a mount surface on which the gyro sensor device  20  is mounted. 
     In this case, also, the lead terminal  3  extends outside from both the long sides of the resin part  2  in a plurality of numbers. The gyro sensor  10  is tilted by the angle θ with respect to the upper surface of the gyro sensor device  1  by supporting with the lead terminal  3 , bent at the bending parts  6   e,    6   f,  and  6   g  in the resin part  2 . In the structure, the length between the bending parts  6   a  and  6   b  is nearly equal to the length between the bending parts  6   c  and  6   d.  This structure can prevent the occurrence of errors in the tilt angle of the gyro sensor device  20  when it is mounted to the mount board  51 . 
     Next, a method of manufacturing the gyro sensor device of the second embodiment will be briefly described. 
     In this case, first, the lead terminal  3  is stamped so that the bending parts  6   e  and  6   g  are formed as projected from and the bonding part  6   f  are formed as depressed from one surface thereof. On the surface, the gyro sensor  10  is mounted. Next, an adhesive (nonconductive adhesive or epoxy based adhesive)  53  is applied to the die pad  5  or the gyro sensor  10 , and then the gyro sensor  10  is placed on the die pad  5  to adhere. 
     Then, the following is carried out by wire bonding: a gold ball  9   b  is provided on the lead terminal  3 , and then a wire  9   a  is formed from the gold ball  9   b,  as a starting point, to the electrode terminal  8 , as an ending point, on the bottom surface of the gyro sensor  10 , for example. In this regard, the gold ball may be provided on the electrode terminal  8 , and the starting and ending points are exchanged. In wire bonding, a tool  81  shown in  FIG. 6  is used. The tool  81  has a shape into which the upper surface of each of a plurality of gyro sensors  10  can be set corresponding to the lead terminal  3 . Here, a bottom surface  80  of the tool  81  makes the angle θ with respect to the lead terminal  3 . Therefore, the bottom surface of the gyro sensor  10  and the bottom surface  80  of the tool  8  are nearly in parallel with each other when the gyro sensor  10  is set in the tool  81 . In wire bonding, placing the tool  81  so that the bottom surface  80  is faced downward and nearly horizontally results in the bottom surface of the gyro sensor  10  being nearly horizontally. As a result, the wire bonding is accurately conducted. 
     Next, the gyro sensor  10  is molded with resin. In this case, the lead terminals  3  exposed from the molded package are extended to have an original shape. Then, the ends  6   h  and  6   i  of the lead terminals  3 , and between the lead terminals  3  are cut off. Next, the lead bending parts  6   b  and  6   d  are bent by fixing the lead terminal  3  between the lead bending part  6   b  and the resin part  2  as well as the lead bonding part  6   d  and the resin part  2 . Next, the lead bending parts  6   a  and  6   c  are bent by fixing the lead terminal  3  between the lead bending part  6   a  and the resin part  2  as well as the lead bonding part  6   c  and the resin part  2 . 
     As described above, a method for manufacturing the gyro sensor device  20 , in which the detection axis G of the gyro sensor and the upper surface of the resin part  2  are set at a desired angle (the angle θ that the detection axis G makes with respect to the vertical direction of a mount surface on which the gyro sensor device  20  is mounted), with high productivity can be provided. Here, the upper surface of the gyro sensor device  20  and the surface on which the gyro sensor device  20  is mounted are in parallel with each other. 
       FIG. 7  is a schematic view illustrating the structure of a gyro sensor device according to a third embodiment of the invention. 
     In a gyro sensor device  30  shown in  FIG. 7 , the gyro sensor  10  is sealed with the resin part  2  so that the gyro sensor  10  is tilted by the angle θ with respect to the vertical direction of a mount surface on which the gyro sensor device  30  is mounted. 
     In this case, also, the lead terminal  3  extends outside from both the long sides of the resin part  2  in a plurality of numbers. The gyro sensor  10  is tilted by the angle θ with respect to the upper surface of the gyro sensor device  30  by supporting with the lead terminal  3 , bent in a step shape at the bending parts  7   e,    7   f,    7   g,    7   h,    7   i,    7   j ,  7   k  and  7   l  in the resin part  2 . In the structure, the length between the bending parts  7   a  and  7   b  is nearly equal to the length between the bending parts  7   c  and  7   d.  This structure can prevent the occurrence of errors in the tilt angle of the gyro sensor device  30  when it is mounted to the mount board  51 . 
     In addition, the gyro sensor  10  can be placed in parallel with the upper surface of the gyro sensor device  30  by placing the gyro sensor  10  parallel on the upper step of the lead terminal  3 . That is, the detection axis G of the gyro sensor  10  can coincide with the vertical direction or make the desired angle θ with respect to the detection axis G by only changing the position of the step for placing the gyro sensor  10 . 
     Next, a method of manufacturing the gyro sensor device of the third embodiment will be described. 
     In this case, the lead terminal  3  is stamped so that the bending parts  7   e ,  7   g,    7   j  and  7   l  are formed as projected from and the bonding part  7   f,    7   h,    7   i  and  7   k  are formed as depressed from one surface thereof. On the surface, the gyro sensor  10  is mounted. Here, the lead terminal  3  is linked in a plurality of numbers (not shown) to have a shape allowing the bottom of a plurality of gyro sensors  10  to be set in it. 
     Solder paste is coated on the electrode terminal  8  on the bottom surface of the gyro sensor  10 , or near the bending part  7   g  or  7   i  of the lead terminal  3 . The solder paste is heated at a temperature of the melting point or more, and cooled down to normal temperature to mechanically and electrically connect the electrode terminal  8  to the lead terminal  3 . 
     Next, the gyro sensor  10  is molded with resin. In this case, the lead terminals  3  exposed from the molded package are extended to have an original shape. Then, the end of the lead terminal  3  and suspending leads are cut off. Next, the bending parts  7   b  and  7   d  are bent by fixing the lead terminal  3  between the bending part  7   b  and the resin part  2  as well as the bonding part  7   d  and the resin part  2 . Next, the bending parts  7   a  and  7   c  are bent by fixing the lead terminal  3  between the bending part  7   a  and the resin part  2  as well as the bonding part  7   c  and the resin part  2 . As described above, a method for manufacturing the gyro sensor device  30  with high productivity can be provided. 
     Next, the gyro sensor  10  mounted in the gyro sensor device of the above embodiments will be described. 
       FIG. 8  is a cross sectional view illustrating the internal structure of the gyro sensor  10 .  FIGS. 9A to 9C  are schematic views illustrating the structure of a support substrate provided in the gyro sensor  10 . 
     As shown in  FIG. 8 , the gyro sensor  10  includes a quartz crystal resonator element  11  as a detection element to detect angular velocity. As shown in  FIGS. 9A and 9B , the quartz crystal resonator element  11  is mechanically and electrically connected to a support substrate  12  with wires  13 , supporting member having flexibility. The support substrate  12  is connected to the bottom surface inside a ceramics package  17  with an adhesive  14 . In addition, at the center of the support substrate  12 , an opening  12   a  is formed. Through the opening  12   a,  the wires  13  are provided from the back surface to the upper surface side of the support substrate  12 . On the upper surface of the ceramics package  17 , a lid  16  made of metal is bonded with a sealing member  19  such as low melting point metal. This structure allows the inside of the ceramics package  17  to be vacuum sealed. A glass lid also can be used as the lid  16 . In this case, low melting point glass is used as the sealing member  19 , for example. The electrode terminal  8  is formed from the external bottom surface to the sidewall of the ceramics package  17 . The electrode terminal  8  is connected to the quartz crystal resonator element  11  through an internal conductive member (not shown) formed in the ceramics package  17 . 
     Here, at least two, provided parallel at the center, out of six wires  13  shown in  FIG. 8  serve as a support member mainly supporting the quartz crystal resonator element  11 . 
       FIG. 10A  is a plan view schematically illustrating the quartz crystal resonator element  11  of the embodiments.  FIG. 10B  is a plan view illustrating a vibration of the detection vibration mode of the quartz crystal resonator element  11 . 
     The quartz crystal resonator element  11  shown in  FIGS. 10A and 10B  is provided with a base  31 , a pair of detection vibration arms  32   a  and  32   b  protruded from the base  31 , a pair of connection parts  33  protruded from the base  31 , and driven vibration elements  34   a,    34   b,    34   c,  and  34   d  provided at ends of the connection parts  33 . Each main surface of the driven vibration elements  34   a,    34   b,    34   c,  and  34   d  includes an elongate groove. Each transverse section of the driven vibration elements  34   a,    34   b ,  34   c,  and  34   d  shows a nearly H-shape. In addition, an exciting electrode (or driving electrode)  36  is formed in each groove. At each end of the driven vibration elements  34   a,    34   b,    34   c,  and  34   d,  respective wide-width parts or weight parts  38   a,    38   b,    38   c,  and  38   d  are provided. Each main surface of the detection vibration elements  32   a  and  32   b  includes an elongate groove. Each transverse section of the detection vibration elements  32   a  and  34   b  shows a nearly H-shape. In each groove, a detection electrode  37  is formed. At the end of the detection vibration element  32   a,  a weight part  35   a  is provided while at the end of the detection vibration element  32   b,  a weight part  35   b  is provided. 
       FIG. 10A  shows the vibration of a driven mode. In the driven mode, each of the driven vibration element  34   a,    34   b,    34   c,  and  34   d  performs a flexural vibration around a root part  39  to the connection part  33  as shown by an arrow A. In the state, the quartz crystal resonator element  11  is rotated around a rotation axis G, nearly perpendicular to the quartz crystal resonator element  11 , at an angular velocity ω. As shown in  FIG. 10B , a resulting Coriolis force F is applied to the weight parts  38   a,    38   b ,  38   c,  and  38   d  in a direction perpendicular to both the direction A of the flexure vibration and the rotation axis G. As a result, the connection part  33  performs a flexural vibration around a root part  33   a  to the base  31  as show by an arrow B. As a counteraction to the vibration, each of the detection vibration elements  32   a  and  32   b  performs a flexural vibration around a root part  40  to the base  31  as show by an arrow C. The flexural vibration shown by the arrow C generates a piezoelectric phenomenon, changing the potential of the detection electrode  37 . The potential change is detected by a detection circuit (not shown) to obtain the angular velocity ω around the detection axis (rotation axis) G. The detection efficiency can be increased if the crystal axis direction of the Z-axis of the quartz crystal resonator element  11  is aligned to the rotation axis G as a result of setting the crystal axis direction of +X/−X axis of the quartz crystal resonator element  11  as the arrow A direction. 
     The detection element that employs the quartz crystal resonator element  11  and is structured as described above can achieve the gyro sensor having a height lower than that employing a tuning fork quartz crystal resonator, the rotation axis coinciding with the extending direction of the detection vibration element, i.e. the tuning fork quartz crystal resonator, since the direction of the rotation axis G coincides with the thickness direction of the quartz crystal resonator element  11 . 
     Here, as shown in  FIG. 8 , three axes are defined as follows: the extending direction of the wire  13 , the support member included in the gyro sensor  10 , is the X-axis; an axis perpendicular to the X-axis in the plane in which the quartz crystal resonator element  11  is placed is the Y-axis; and an axis perpendicular to both the X-axis and Y-axis is the Z-axis. Assuming that the tilt direction of the gyro sensor  10  is set to coincide with the X-axis direction as shown in  FIGS. 11A and 11B . In this case, a frequency difference occurs between the resonance frequencies of wires  13   a  and  13   b  shown in  FIGS. 11A and 11B , possibly resulting in the operational conditions of the gyro sensor  10  being unstable. 
     That is, when the detection axis G is tilted so as to have the angle θ by setting a side adjacent to the wire  13   a  higher than a side adjacent to the wire  13   b  as shown in  FIG. 11B , with respect to the direction of the X-axis component of the gravity acceleration, the extending direction of the wire  13   a  is opposite to the extending direction of the wire  13   b.  Therefore, the wires  13   a  and  13   b  are differently influenced by the acceleration (difference in the direction of inertial force). For example, the following are defined as shown in  FIG. 11C : the resonance frequency of the quartz crystal resonator element  11  is fref, and the resonance frequency of each of the wires  13   a  and  13   b  is f0 when the quartz crystal resonator  11  is placed horizontally. In the tilted state, tensile force is produced in the wire  13   a,  while compressive force is produced in the wire  13   b  by the influence of the X-axis component of the gravity acceleration, resulting in the resonance frequency fa of the wire  13   a  being higher and the resonance frequency fb of the wire  13   b  being lower. As a result, the resonance frequencies of the wires  13   a  and  13   b  may greatly differ in each other. If the resonance frequencies of the wires  13   a  and  13   b  greatly differ in each other, the coupling of resonance energy is likely to occur due to a close approach to the resonance frequency of the quartz crystal resonator element  11 , and the mounted condition of the quartz crystal resonator element  11  is likely to be unstable. 
     In the first embodiment, the gyro sensor  10  is mounted in the gyro sensor device  1  so that the tilt direction of the gyro sensor  10  (the quartz crystal resonator element  11 ) coincides with the Y-axis direction as shown in  FIGS. 12A and 12B . That is, when the wires  13   a  and  13   b  are disposed so that their tilt directions are symmetric with respect to the center axis, the acceleration equally influences both the wires  13   a  and  13   b  when the acceleration is applied in the Y-axis direction. As a result, the frequency difference hardly occurs between the resonance frequencies of the wires  13   a  and  13   b  as shown in  FIG. 12C . This structure brings, for example, an advantage of easy controlling a frequency adjustment or the like. In addition, the wire  13  is less influenced by the acceleration since the extending direction of the wires  13   a  and  13   b  does not coincide with the acceleration direction (the Y-axis direction). Therefore, the variation amount of each resonance frequency of the wires  13   a  and  13   b  can be lessened as shown in  FIG. 12C , bringing an advantage in that the coupling of resonance energy hardly occurs. 
     Further, when the tilt directions of the wires  13   a  and  13   b  are set symmetrically with respect to the center axis as shown in  FIG. 12A , and the extending directions of the wires  13   a  and  13   b  are perpendicular to the tilt direction, the changing characteristics of each resonance frequency of the wires  13   a  and  13   b  are nearly equal even though the direction of the acceleration in the Y-axis direction is opposite (shown as G) as the sensor is placed horizontally. This structure allows the gyro sensor of the embodiments to be mounted horizontally, for example. 
     The gyro sensor device including the gyro sensor  10  structured as described above can suppress adverse influences, given by the changing characteristic of the resonance frequencies of the wires  13   a  and  13   b,  to the gyro sensor device with respect to the acceleration in the traveling direction of a vehicle, since the gyro sensor device is installed in the vehicle so that the Y-axis direction coincides with the acceleration direction of the vehicle. 
     The wire  13  may be one that is made of quartz, integrated to the base  31  of the quartz crystal resonator element  11 , and shaped in a reed. 
     The entire disclosure of Japanese Patent Application Nos: 2006-216505, filed Aug. 9, 2006 and 2006-249404, filed Sep. 9, 2006 are expressly incorporated by reference herein.

Technology Classification (CPC): 7