JP2006269859A - Physical quantity sensor and lead frame used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size of a physical quantity sensor in a lead frame used for the physical quantity sensor.
SOLUTION: Stage portions 7 and 9 on which physical quantity sensor chips 3 and 5 are placed, a frame portion 11 having a plurality of leads 15 and 17 arranged around the same, at least one lead 17 and the stage portion. The connecting portions 19 and 21 incline the stage portions 7 and 9 about the reference axis L1 with respect to the frame portion 11. It has an easily deformable portion, and sheet-like insulating films 31 and 33 made of an electrically insulating material are arranged on the surfaces of the stage portions 7 and 9 on which the physical quantity sensor chips 3 and 5 are placed. A lead frame 1 is provided.
[Selection] Figure 1

Description

  The present invention relates to a physical quantity sensor that measures the azimuth and direction of a physical quantity such as magnetism and gravity, and a lead frame used therefor.

2. Description of the Related Art Recently, mobile terminal devices such as mobile phones have appeared that have a GPS (Global Positioning System) function for displaying user position information. In addition to this GPS function, by providing a function for accurately detecting geomagnetism and a function for detecting acceleration, it is possible to detect the azimuth, direction, or movement direction in the three-dimensional space of the mobile terminal device carried by the user. it can.
In order to provide the mobile terminal device with the functions described above, it is necessary to incorporate a physical quantity sensor such as a magnetic sensor or an acceleration sensor in the mobile terminal device. Further, in order to be able to detect the orientation and acceleration in the three-dimensional space by such a physical quantity sensor, it is necessary to incline the installation surface of the physical quantity sensor chip.

Here, various types of physical quantity sensors described above are currently provided. For example, a magnetic sensor that detects magnetism and does not tilt the installation surface is known as one of them. This magnetic sensor is mounted on the surface of a substrate and is one magnetic sensor chip (physical quantity sensor chip) that is sensitive to magnetic components of external magnetic fields in two directions (X and Y directions) orthogonal to each other along the surface. And the other magnetic sensor chip that is placed on the surface of the substrate and is sensitive to the magnetic component of the external magnetic field in the direction perpendicular to the surface (Z direction).
This magnetic sensor measures the geomagnetic component as a vector in a three-dimensional space using the magnetic component detected by the pair of magnetic sensor chips.

  However, this magnetic sensor has the disadvantage that the thickness (height relative to the Z direction) increases because the other magnetic sensor chip is placed in a state of being perpendicular to the surface of the substrate. Therefore, in order to make the thickness as small as possible, a physical quantity sensor (see, for example, Patent Documents 1 to 3) in which the installation surface is inclined as described above is preferably used.

  Further, as this type of physical quantity sensor, there is an acceleration sensor as described in Patent Document 1. In this one-side beam structure acceleration sensor, the acceleration sensor chip (physical quantity sensor chip) is inclined in advance with respect to the mounting substrate, so that even if the sensor packaging is placed on the surface of the mounting substrate, it depends on the inclination direction. In addition, the sensitivity in the predetermined axis direction can be kept high, and the sensitivity in the other axis direction including the direction along the surface of the substrate can be reduced.

  As shown in FIG. 12, the physical quantity sensor in which the physical quantity sensor chip is tilted, for example, a magnetic sensor, includes stage portions 53 and 54 on which magnetic sensor chips (physical quantity sensor chips) 51 and 52 are mounted, and a magnetic sensor chip 51. , 52 is manufactured using a lead frame 58 including a plurality of leads 55 for electrically connecting to the outside and a frame portion 57 having a connecting lead 56 for supporting the stage portions 53, 54. Note that an easily deformable portion 56 a that tilts the stage portions 53 and 54 about the reference axis L with respect to the frame portion 57 is provided at one end of the connecting lead 56.

When manufacturing a magnetic sensor using the lead frame 58, a liquid adhesive is applied to the surfaces of the stage portions 53 and 54, and the magnetic sensor chips 51 and 52 are attached to the surfaces of the stage portions 53 and 54. The physical quantity sensor chips 51 and 52 and the leads are electrically connected by the wire 59. Thereafter, the easily deformable portion 56 a of the connecting lead 56 is deformed, and the stage portions 53 and 54 are inclined with respect to the frame portion 57 around the reference axis L.
JP-A-9-292408 JP 2002-156204 A JP 2004-128473 A

However, in the conventional physical quantity sensor, since the physical quantity sensor chips 51 and 52 arranged on the stage portions 53 and 54 are inclined and arranged, a sufficient area and height are required for packaging. There has been a limit to compactly incorporating it in a small portable terminal device. In particular, in addition to the electrical connection leads 55, it is necessary to separately provide connection leads 56 for inclining the stage portions 53, 54 around the stage portions 53, 54, so that the frame portion 57 can be formed small. As a result, there is a limit to downsizing the physical quantity sensor.
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a physical quantity sensor that can be reduced in size and a lead frame used therefor.

In order to solve the above problems, the present invention proposes the following means.
The invention according to claim 1 is a stage unit on which a physical quantity sensor chip is placed, a frame unit including a plurality of leads disposed around the stage unit, and a connecting unit that connects at least one of the leads and the stage unit. The connecting portion has an easily deformable portion that inclines the stage portion around a reference axis with respect to the frame portion, and is on the surface of the stage portion on which the physical quantity sensor chip is placed. A lead frame is proposed in which a sheet-like insulating film made of an electrically insulating material is provided.

When manufacturing a physical quantity sensor in which the physical quantity sensor chip is inclined with respect to the frame portion using the lead frame according to the present invention, first, the physical quantity sensor chip is placed on the surface of each stage portion via an insulating film. Next, the physical quantity sensor chip and the lead are electrically connected by wire bonding. Thereafter, by pressing the stage portion while the frame portion is fixed, the easily deformable portion is deformed, and the stage portion and the physical quantity sensor chip can be inclined with respect to the frame portion around the reference axis.
Here, since the physical quantity sensor chip and the stage part are electrically insulated by the insulating film, the physical quantity sensor chip and the lead connected to the stage part are electrically insulated. Therefore, the electrical connection with the physical quantity sensor chip by wire bonding described above can be applied to the lead connected to the stage portion, that is, the physical quantity sensor chip can be electrically connected without changing the size of the lead frame. Increase the number of leads.

According to a second aspect of the present invention, in the lead frame according to the first aspect, two stage portions are arranged inward of the same frame portion, and one stage portion faces the other stage portion. Proposed lead frames are characterized in that protruding leads are formed.
According to the lead frame of the present invention, the protruding lead is formed integrally with the stage portion and the lead connected to the stage portion. For this reason, when the lead connected to one stage part is used as a ground electrode or the like that can be shared by two physical quantity sensor chips arranged in each stage part, the physical quantity arranged in one stage part The sensor chip and the lead are connected by wire bonding, and among the physical quantity sensor chips arranged on the other stage portion, the end facing the one stage portion and the protruding lead may be connected by wire bonding. .

  In particular, even when the stage part and the physical quantity sensor chip are tilted with respect to the frame part around the reference axis located in the connecting part, the physical quantity sensor chip disposed on the projecting lead on one stage part side and the other stage part Since the distance from the end of the wire does not change greatly, the wire does not extend, and the length of the wire can be shortened in advance.

According to a third aspect of the present invention, in the lead frame according to the first or second aspect, the stage portion and the connecting portion are formed of extended leads extending from the tips of the leads connected to the stage portion. A lead frame characterized by the above is proposed.
According to the lead frame according to the present invention, the lead frame and the physical quantity sensor can be simplified by configuring the stage part and the connecting part from the extended lead having the same shape as the lead. Cost reduction can be achieved.

  According to a fourth aspect of the present invention, in the lead frame according to the third aspect, the stage portion is formed of a plurality of the extension leads, and is arranged at a tip of each extension lead in a region that does not overlap the physical quantity sensor chip. A lead frame is proposed in which an exposed lead is formed.

When manufacturing a physical quantity sensor using this lead frame, even if each exposed lead and the physical quantity sensor chip are electrically connected by wire bonding and then the extension lead is inclined with respect to the frame portion, The positional relationship with each exposed lead does not change. For this reason, it is possible to reliably prevent the wire disposed between the physical quantity sensor chip and the exposed lead from being deformed.
In addition, since the physical quantity sensor chip can be electrically connected to a plurality of exposed leads constituting the stage unit, the number of leads that can be electrically connected to the physical quantity sensor chip can be further increased.

  According to a fifth aspect of the present invention, in the lead frame according to any one of the first to fourth aspects, the plurality of leads are connected to the stage portion via the connecting portion. And a second lead arranged in a direction along the reference axis along with the first lead, and an adjacent lead extending from the tip of the second lead through the reference axis is formed on the second lead. The adjacent leads are arranged side by side with the stage portion in a direction along the reference axis, and are formed so as to be tiltable by moving around the reference axis with respect to the frame portion. A lead frame is proposed.

According to the lead frame of the present invention, the adjacent lead can be tilted around the same reference axis as the stage unit and the physical quantity sensor chip, that is, the adjacent lead can be tilted in the same direction as the stage unit and the physical quantity sensor chip. And can be tilted at the same tilt angle.
Therefore, when manufacturing a physical quantity sensor, after the physical quantity sensor chip and the adjacent lead are electrically connected by wire bonding, the stage part, the physical quantity sensor chip, and the adjacent lead are inclined in the same direction, whereby the adjacent lead and the stage part are In addition, the relative distance from the physical quantity sensor chip can be kept constant. That is, the wire arranged between the physical quantity sensor chip and the adjacent lead does not extend, and the length of the wire can be formed short in advance.

In addition, since the adjacent lead and the stage part can be inclined at the same inclination angle, even if a physical quantity sensor chip larger than the surface of the stage part is arranged on the surface of the stage part, the physical quantity sensor chip protruding from the stage part is adjacent. Can be supported by leads. However, in this case, it is preferable to dispose an insulating film between the physical quantity sensor chip and the adjacent lead.
Further, in the case where the stage portion is constituted by an extension lead, the adjacent lead may be formed in the same manner as the extension lead, and this lead frame can be easily manufactured.

According to a sixth aspect of the present invention, there is provided the lead frame according to any one of the first to fifth aspects, wherein a fixing layer is formed on the front surface and the back surface of the insulating film. is suggesting.
The fixing layer allows the stage part and the physical quantity sensor chip to be bonded to the insulating film, such as temporary bonding that can be re-bonded after the bonding, or permanent bonding that cannot be re-bonded after the bonding. Any function may be provided.
According to the lead frame according to the present invention, the physical quantity sensor chip is formed on the surface of the stage portion by the fixing layers formed on the front and back surfaces of the insulating film only by arranging the physical quantity sensor chip on the surface of the stage portion via the insulating film. Adhere to the surface. That is, it is sufficient to prepare an insulating film in which a fixing layer is formed in advance and then apply a physical quantity sensor chip to the insulating film, so that the thickness accuracy of the fixing layer is improved as compared to the case where an adhesive is applied as in the past. Can be easily achieved.

  Conventionally, a liquid adhesive is often used for bonding between the stage part and the physical quantity sensor chip, and there is a risk that liquid dripping will occur and the liquid adhesive will adhere to the surface of the leads and protruding leads in addition to the stage part. However, by using this insulating film, it is possible to secure the surface area of leads and protruding leads required for wire bonding.

According to a seventh aspect of the present invention, the stage portion, the physical quantity sensor chip, and the plurality of leads are integrally fixed using the lead frame according to any one of the first to sixth aspects. A physical quantity sensor characterized by
According to the physical quantity sensor according to the present invention, the physical quantity sensor chip and the stage portion are electrically insulated by the insulating film, so that the physical quantity sensor chip and the lead connected to the stage portion are electrically insulated. Become. Therefore, the electrical connection with the physical quantity sensor chip by wire bonding can be applied to the lead connected to the stage portion, that is, the lead that can be electrically connected to the physical quantity sensor chip without changing the size of the lead frame. The number of can be increased.

According to the first and seventh aspects of the present invention, since the lead coupled to the stage portion can also be used for electrical connection with the magnetic sensor chip, a lead dedicated for coupling to the stage portion is separately provided in the frame portion. There is no need. Therefore, the size of the frame portion surrounding the stage portion can be reduced as compared with the case where a lead dedicated for connection is provided in the frame portion, and the physical quantity sensor can be downsized.
In addition, when the lead used to connect to the stage unit is used for electrical connection with the physical quantity sensor chip, more signals can be input and output to the physical quantity sensor chip. Therefore, as a result, it is possible to provide a highly functional physical quantity sensor.

  According to the second aspect of the invention, since one lead can be electrically connected to two physical quantity sensor chips, the number of leads used for electrical connection with the physical quantity sensor chip can be reduced. Miniaturization can be achieved. In addition, since the wire disposed on the protruding lead can be formed short, the manufacturing cost of the physical quantity sensor can be reduced.

  According to the invention of claim 3, the lead frame and the physical quantity sensor can be simplified by configuring the stage part and the connecting part from the extended lead having the same shape as the lead. The manufacturing cost can be reduced.

  According to the fourth aspect of the present invention, since the wire disposed between the physical quantity sensor chip and the adjacent lead can be formed short, the manufacturing cost of the physical quantity sensor can be reduced. In addition, since the plurality of leads coupled to the stage unit can be used for electrical connection with the magnetic sensor chip, the physical quantity sensor can be further reduced in size.

  According to the fifth aspect of the present invention, since the wire disposed between the physical quantity sensor chip and the adjacent lead can be formed short, the manufacturing cost of the physical quantity sensor can be reduced. In addition, since it is not necessary to change the design of the lead frame according to the size of the physical quantity sensor chip, the lead frame can be used for general purposes. Furthermore, since the adjacent lead can be formed in the same manner as the extension lead, this lead frame can be easily manufactured.

According to the invention of claim 6, since the thickness accuracy of the fixing layer can be easily improved, the physical quantity sensor chip is inclined with respect to the surface of the stage portion based on the variation in the thickness of the fixing layer. Can be suppressed.
In addition, by using an insulating film having an adhesive layer formed on the front and back surfaces, it is possible to secure the surface areas of leads and protruding leads required for wire bonding, and thus a physical quantity sensor can be easily manufactured.

1 to 6 show an embodiment of the present invention. A magnetic sensor (physical quantity sensor) according to this embodiment has a direction and a magnitude of an external magnetic field by two magnetic sensor chips inclined with respect to each other. It is manufactured using a lead frame formed by subjecting a metal plate made of a thin plate-like copper material or the like to press working and etching.
As shown in FIGS. 1 and 2, the lead frame 1 includes two stage portions 7 and 9 for arranging magnetic sensor chips (physical quantity sensor chips) 3 and 5 that are formed in a rectangular plate shape in plan view, and a stage. A frame portion 11 for supporting the portions 7 and 9; and connecting portions 19 and 21 for connecting the stage portions 7 and 9 and the frame portion 11 to each other. The stage portions 7 and 9, the frame portion 11 and the connecting portion 19 are provided. , 21 are integrally formed. The frame portion 11 includes a rectangular frame portion 13 formed in a rectangular shape in plan view so as to surround the stage portions 7 and 9, and a plurality of leads 15 and 17 protruding inward from the rectangular frame portion 13. The connecting portions 19 and 21 connect the stage portions 7 and 9 to the leads 17 (three in the illustrated example).

  Here, the leads 15 and 17 are electrically connected to bonding pads (not shown) of the magnetic sensor chips 3 and 5, and are spaced apart from each other. The two stage portions 7 and 9 are arranged side by side along one side of the rectangular frame portion 13, and the leads 17 connected to the stage portions 7 and 9 are arranged in the arrangement direction of the two stage portions 7 and 9. It extends. Further, the leads 17 connected to the respective stage portions 7 and 9 extend in directions facing each other.

The stage portions 7 and 9 and the connecting portions 19 and 21 are composed of a plurality of extension leads 23 and 25 that integrally extend from the tips of the leads 17. The extension leads 23 and 25 are separated from each other. Are arranged. Projecting leads 27 and 29 projecting toward the stage portions 7 and 9 are formed at the tips of the extension leads 23 and 25 facing each other. These projecting leads 27 and 29 are formed integrally with the leads 17 connected to the stage portions 7 and 9, and the magnetic sensor chips 3 and 5 are mounted on the stage portions 7 and 9. It is formed at a position that does not overlap with 3,5.
On the surfaces 23a, 25a, 27a, 29a of the extended leads 23, 25 and the protruding leads 27, 29, concave grooves are formed by photoetching, and the thicknesses of the stage portions 7, 9 and the connecting portions 19, 21 are formed. The thickness is formed thinner than the lead 17 and a protruding piece described later.

One sheet-like insulating film 31, 33 is arranged at a position corresponding to each stage portion 7, 9 on the surface 23 a, 25 a of each extension lead 23, 25, that is, each insulating film 31. , 33 are arranged over the plurality of extension leads 23, 25. The insulating films 31 and 33 are made of an electrically insulating material.
A fixed layer (not shown) is formed in advance on the front and back surfaces of the insulating films 31 and 33. This fixing layer allows the stage portions 7 and 9 and the magnetic sensor chips 3 and 5 to be bonded to the respective insulating films 31 and 33. Temporary bonding that allows re-bonding after the bonding or re-bonding after the bonding It is sufficient to have any function such as permanent adhesion which is impossible. Therefore, when the insulating films 31 and 33 are attached to the stage portions 7 and 9, the magnetic sensor chips 3 and 5 are arranged on the surfaces 23 a and 25 a of the stage portions 7 and 9 via the insulating films 31 and 33. Only, the magnetic sensor chips 3 and 5 can be bonded to the stage portions 7 and 9.

A pair of projecting pieces 35 and 37 projecting toward the back surfaces 23d and 25d of the extension leads 23 and 25 are formed at the tips of the projecting leads 27 and 29 facing each other.
Note that the photoetching process described above is also applied to the base end portions of the projecting pieces 35 and 37 that bend the projecting pieces 35 and 37 with respect to the extension leads 23 and 25 and the projecting leads 27 and 29. , 9 and the same thickness. That is, since the base end portions of the protruding pieces 35 and 37 are formed thinner than the other portions and can be easily deformed, the inclination angle of the protruding pieces 35 and 37 with respect to the stage portions 7 and 9 is set with high accuracy. It becomes possible.

Next, a method for manufacturing a magnetic sensor using the lead frame 1 described above will be described.
First, the magnetic sensor chips 3 and 5 are bonded to the surfaces 23a and 25a of the stage portions 7 and 9 through the insulating films 31 and 33, and then the wires 38 are arranged by wire bonding, and the surfaces of the magnetic sensor chips 3 and 5 are bonded. A bonding pad (not shown) disposed on the lead and the leads 15 and 17 are electrically connected. A similar wire 38 is also disposed between the bonding pad of one magnetic sensor chip 3 and the surface 29a of the protruding lead 29 located on the stage portion 9 side where the other magnetic sensor chip 5 is disposed.

In this case, the same lead 17 is electrically connected to the two magnetic sensor chips 3 and 5, but the lead 17 is shared by the two magnetic sensor chips 3 and 5, for example, a ground electrode. It can be used as possible.
When the wires 38 are arranged, the bonding portions between the wires 38 and the magnetic sensor chips 3 and 5 and the bonding portions between the leads 15 and 17 change with each other at the stage of tilting the stage portions 7 and 9. The material of the wire 38 is preferably easy to bend and soft.

Next, a resin mold portion for integrally fixing the magnetic sensor chips 3 and 5, the stage portions 7 and 9, and the leads 15 and 17 is formed.
That is, first, as shown in FIG. 3, the rectangular frame portion 13 of the lead frame 1 is disposed on the surface E2 of the mold E having the recess E1. At this time, the leads 15 and 17, the stage portions 7 and 9, the magnetic sensor chips 3 and 5, and the protruding pieces 35 and 37 inside the rectangular frame portion 13 are arranged above the recess E1. Further, in this state, the magnetic sensor chips 3 and 5, the stage portions 7 and 9, and the protruding pieces 35 and 37 are arranged in order from the concave portion E1 side to the upper side.
A mold F having a flat surface F1 is arranged above the protruding pieces 35 and 37, and is configured to sandwich the rectangular frame portion 13 of the lead frame 1 together with the mold E described above.

  As shown in FIG. 4, when the rectangular frame portion 13 is sandwiched between the pair of upper and lower molds E and F, the tip portions 35a and 37a of the protruding pieces 35 and 37 are formed by the flat surface F1 of the mold F. Is pressed. At this time, the connecting portions 19 and 21 connected to the respective stage portions 7 and 9 are deformed, and the stage portion 7 with respect to each lead 17 is centered on the reference axis L1 connecting the connecting portions 19 and 21 to each other. , 9 will move. Here, since the connection parts 19 and 21 are thinly formed by photoetching and are easily deformable parts that can be easily deformed, the stage parts 7 and 9 can be easily inclined. Thereby, the magnetic sensor chips 3 and 5 together with the stage portions 7 and 9 are inclined at a predetermined angle with respect to the rectangular frame portion 13 and the flat surface F1.

Thereafter, molten resin is injected into the molds E and F with the tip portions 35a and 37a of the protruding pieces 35 and 37 being pressed by the flat surface F1 of the mold F, and the magnetic sensor chips 3 and 5 are placed inside the resin. A resin mold part to be buried in is formed. As a result, as shown in FIGS. 5 and 6, the magnetic sensor chips 3 and 5 are fixed inside the resin mold portion 41 while being inclined with respect to each other. The resin used here is preferably a material having high fluidity so that the inclination angles of the magnetic sensor chips 3 and 5 and the stage portions 7 and 9 are not changed by the flow of the resin.
Finally, the rectangular frame portion 13 is cut off, and the leads 15 and 17 are individually cut and electrically separated, and the manufacture of the magnetic sensor 40 is completed.

  The magnetic sensor chips 3 and 5 provided in the magnetic sensor 40 manufactured as described above are embedded in the resin mold portion 41 and are inclined with respect to the lower surface 41 a of the resin mold portion 41. Further, the one end portions 3b and 5b of the magnetic sensor chips 3 and 5 facing each other face the upper surface 41c side of the resin mold portion 41, and the surfaces 3a and 5a are inclined at an acute angle. Here, the acute angle indicates an angle θ formed by the front surface 23a of the stage portion 7 and the back surface 25d of the stage portion 9.

The magnetic sensor chip 3 is sensitive to magnetic components in two directions of an external magnetic field, and these two sensitive directions are directions orthogonal to each other along the surface 3a of the magnetic sensor chip 3 (A direction and B). Direction).
The magnetic sensor chip 5 is sensitive to magnetic components in two directions of an external magnetic field, and these two sensitive directions are directions orthogonal to each other along the surface 5a of the magnetic sensor chip 5 (C direction and D direction).
Here, the A and C directions are parallel to the reference axis L1, and are opposite to each other. Further, the B and D directions are directions orthogonal to the reference axis L1, and are opposite to each other.

Furthermore, a plane defined by the A and B directions along the surface 3a (A-B plane) and a plane defined by the C and D directions along the surface 5a (C-D plane) are acute with each other. Cross at an angle θ.
Note that the angle θ formed by the AB plane and the CD plane is greater than 0 ° and not greater than 90 °. Theoretically, if the angle is greater than 0 °, the orientation of the three-dimensional geomagnetism Can be measured. However, in practice, the angle is preferably 20 ° or more, and more preferably 30 ° or more.

The back surfaces 15 a and 17 a of the plurality of leads 15 and 17 for electrical connection to the outside of the magnetic sensor chips 3 and 5 are exposed on the lower surface 41 a side of the resin mold portion 41. One end of the lead 15 is electrically connected to the magnetic sensor chips 3 and 5 by a metal wire 29, and the connecting portion is embedded in the resin mold portion 41.
For example, the magnetic sensor 40 is mounted on a substrate in a portable terminal device (not shown). In this portable terminal device, the direction of geomagnetism measured by the magnetic sensor 40 is shown on the display panel of the portable terminal device.

  According to the lead frame 1 and the magnetic sensor 40 described above, the magnetic sensor chips 3 and 5 and the stage portions 7 and 9 are electrically insulated from each other by the insulating films 31 and 33. The leads 17 connected to the terminals 7 and 9 are electrically insulated. Therefore, the above-described electrical connection with the magnetic sensor chips 3 and 5 by wire bonding can be applied to the leads 17 connected to the stage portions 7 and 9, that is, the size of the lead frame 1 is changed. In addition, the number of leads that can be electrically connected to the magnetic sensor chips 3 and 5 can be increased.

Therefore, it is not necessary to separately provide a lead dedicated for connection with the stage portions 7 and 9 in the frame portion 11, and the size of the frame portion 11 surrounding the stage portions 7 and 9 can be increased as compared with the case where a lead dedicated for connection is provided. Therefore, the magnetic sensor 40 can be reduced in size.
In addition, when the lead used for connection with the stage portions 7 and 9 in the past is used for electrical connection with the magnetic sensor chips 3 and 5, a larger amount of insertion is required with respect to the magnetic sensor chips 3 and 5. Since output can be performed, it is possible to provide a highly functional magnetic sensor 40 as a result.

Further, by arranging a wire 38 between the bonding pad of one magnetic sensor chip 3 and the surface 29a of the protruding lead 29 located on the stage part 9 side where the other magnetic sensor chip 5 is arranged, the same lead 17 is provided. Can be electrically connected to the two magnetic sensor chips 3 and 5, the number of leads 17 used for electrical connection with the magnetic sensor chips 3 and 5 can be reduced, and the magnetic sensor 40 can be further reduced in size. .
Further, even if the stage portions 7 and 9 and the magnetic sensor chips 3 and 5 are inclined with respect to the frame portion 11 around the reference axis L1, the one end portion 3b of one magnetic sensor chip 3 and the other magnetic sensor chip 5 are arranged. Since the distance from the protruding lead 29 on the side does not change greatly, the wire 38 disposed on the protruding lead 29 does not extend. Therefore, since the wire 38 arranged on the protruding lead 29 can be formed short, the manufacturing cost of the magnetic sensor 40 can be reduced.

Further, since the stage portions 7 and 9 and the connecting portions 19 and 21 are constituted by extension leads 23 and 25 having the same shape as the lead 17, the shape of the lead frame 1 can be simplified, and the lead frame can be simplified. 1 and the manufacturing cost of the magnetic sensor 40 can be reduced.
Furthermore, by simply arranging the magnetic sensor chips 3 and 5 on the front surfaces 23a and 25a of the stage portions 7 and 9 through the insulating films 31 and 33, the fixing layers formed on the front and back surfaces of the insulating films 31 and 33 The magnetic sensor chips 3 and 5 are bonded to the surfaces 23a and 25a of the stage portions 7 and 9. That is, the insulating films 31 and 33 having the fixing layer formed in advance are prepared, and the magnetic sensor chips 3 and 5 may be attached thereto. It is possible to easily improve the layer thickness accuracy. Therefore, it is possible to suppress the magnetic sensor chips 3 and 5 from being inclined with respect to the surfaces 23a and 25a of the stage portions 7 and 9 based on the variation in the thickness of the fixed layer.

  Conventionally, a liquid adhesive is often used for bonding between the stage portions 7 and 9 and the magnetic sensor chips 3 and 5, so that dripping occurs and the liquid adhesive leads to other than the stage portions 7 and 9. 17 and the surfaces 27a and 29a of the projecting leads 27 and 29 may be attached. By using the insulating films 31 and 33, the surface area of the lead 17 and the projecting leads 27 and 29 required for wire bonding is secured. can do. Therefore, the magnetic sensor 40 can be easily manufactured.

  In the above embodiment, the wires 38 are arranged between the leads 17 connected to the stage units 7 and 9 and the magnetic sensor chips 3 and 5 mounted on the stage units 7 and 9. However, the present invention is not limited to this. For example, as shown in FIGS. 7 and 8, the magnetic sensor chips 3 and 5 and the projecting leads (exposed leads) 26 and 28 arranged on the stage portions 7 and 9, respectively. A wire 39 may be arranged between the two. These protruding leads 26 and 28 are formed at the tips of the extension leads 23 and 25 in a region that does not overlap with the magnetic sensor chips 3 and 5, and are the same as the protruding leads 27 and 29 in the above embodiment. is there.

In the case of this configuration, when manufacturing the magnetic sensor, the protruding leads 26 and 28 and the magnetic sensor chips 3 and 5 are electrically connected by wire bonding, and then the extension lead 23 is inclined with respect to the lead 17. However, the positional relationship between the extended leads 23 and the protruding leads 26 and 28 does not change. For this reason, it can prevent reliably that the wire 39 distribute | arranged between the magnetic sensor chips 3 and 5 and the protrusion leads 26 and 28 deform | transforms. Therefore, the length of the wire 39 can be shortened in advance, and the manufacturing cost of the magnetic sensor can be reduced.
Further, since the physical quantity sensor chips 3 and 5 can be electrically connected to the plurality of protruding leads 26 and 28 constituting the stage portions 7 and 9, the number of leads 17 that can be electrically connected to the magnetic sensor chips 3 and 5 is further increased. Can be increased. That is, since the plurality of leads 17 connected to the stage portions 7 and 9 can be used for electrical connection with the magnetic sensor chips 3 and 5, respectively, the magnetic sensor can be further reduced in size.

In the above embodiment, only the extension leads 23 and 25 functioning as the stage portions 7 and 9 are extended from the tip of the lead 17, but the stage portion may be extended from the tip of the lead in the same manner as the extension lead 23. 7 and 9 may not be provided.
That is, for example, as shown in FIGS. 7 and 8, the second lead 44 arranged in the direction along the reference axis L <b> 1 together with the first lead 43 connected to the extension leads 23, 25 is moved from the tip thereof to the reference axis. The lead frame 46 may be configured by forming an adjacent lead 45 extending through L1. Here, the first lead 43 is the same as the lead 17 in the above embodiment.

The adjacent lead 45 is disposed substantially parallel to the extended leads 23 and 25 with a space therebetween, and the length thereof is substantially equal to the length obtained by adding the protruding leads 26 and 28 to the extended lead 23. A protruding piece 47 similar to the protruding pieces 35 and 37 formed at the tips of the protruding leads 26 and 28 is formed at the tip of the adjacent lead 45. Similar to the extended leads 23 and 25, the adjacent lead 45 is formed to be inclined with respect to each second lead 44 by moving around the reference axis L1.
In the case of this configuration, the adjacent lead 45 can be tilted about the same reference axis L1 as the extension leads 23 and 25, that is, the adjacent lead 45 can be tilted in the same direction as the extension leads 23 and 25. , And can be tilted at the same tilt angle.

  From the above, when manufacturing a magnetic sensor using the lead frame 46, the magnetic sensor chips 3 and 5 and the adjacent lead 45 are electrically connected by wire bonding, and then extended using the protruding piece 47. By tilting the leads 23 and 25 and the adjacent lead 45 in the same direction, the relative distance between the adjacent lead 45 and the extension leads 23 and 25 can be kept constant. That is, the wire 48 arranged between the magnetic sensor chips 3 and 5 and the adjacent lead 45 does not extend, and the length of the wire 48 can be shortened in advance. Therefore, the manufacturing cost of the magnetic sensor can be reduced.

Further, since the adjacent lead 45 and the stage portions 7 and 9 can be inclined at the same inclination angle, even if the large magnetic sensor chips 3 and 5 are arranged to protrude from the stage portions 7 and 9, the stage portions 7 and 9 The magnetic sensor chips 3 and 5 that protrude from the base can be supported by the adjacent leads 45, and the design of the lead frame 46 corresponding to the size of the magnetic sensor chips 3 and 5 is not required. Can be used for However, in this case, it is preferable to dispose the insulating films 31 and 33 between the magnetic sensor chips 3 and 5 and the adjacent leads 45.
Furthermore, since the adjacent lead 45 has the same shape as the extension leads 23 and 25, the lead frame 46 can be easily manufactured.

  Further, the lead frame 1 is formed to incline the two magnetic sensor chips 3 and 5 around the reference axis L1 parallel to each other. However, the present invention is not limited to this. For example, as shown in FIG. You may form the lead frame 42 which inclines the two magnetic sensor chips 3 and 5 centering on the orthogonal reference axis lines L1 and L2. In this configuration, the leads 17 connected to the stage portions 7 and 9 are preferably orthogonal to each other. In this case, since the two sensitive directions (A direction and C direction) of the two magnetic sensor chips 3 and 5 orthogonal to each other can be set along the lower surface 41a of the resin mold portion 41, the lower surface 41a The along magnetism can be measured with high accuracy.

Further, in the case of this configuration, as shown in the figure, the two magnetic sensor chips 3 and 5 can be arranged along one diagonal line L3 of the rectangular frame portion 13, so that this lead frame 42 is used. When the stage portions 7 and 9, the magnetic sensor chips 3 and 5, and the leads 15 and 17 are integrally molded with resin, it is possible to prevent the flow of the molten resin from being hindered.
That is, when the resin mold portion 41 is formed, the molten resin is often allowed to flow from the corner portion of the rectangular frame portion 13 into the resin forming space formed by the molds E and F. However, the one diagonal line L3 described above is used. The molten resin is allowed to flow from one corner 13a of the rectangular frame portion 13 located on the other diagonal line L4 intersecting with the other corner portion 13b, so that the stage portions 7, 9 and the magnetic sensor chip 3, 5 does not hinder the flow of the molten resin.
Therefore, the molten resin can be easily reached from one corner 13a to the other corner 13b, and resin filling failure can be reliably prevented. Further, it is possible to prevent the tilting angles of the stage portions 7 and 9 and the magnetic sensor chips 3 and 5 from being unexpectedly changed by pressing the stage portions 7 and 9 and the magnetic sensor chips 3 and 5 due to the flow of the molten resin. The tilt angle of the magnetic sensor chips 3 and 5 can be set with high accuracy.

The stage portions 7 and 9 and the connecting portions 19 and 21 are composed of a plurality of extension leads 23 and 25 integrally extending from the leads 17. However, the present invention is not limited to this, and the connecting portions are not limited thereto. It is only necessary that the stage portions 7 and 9 and the lead 17 are connected to each other through the pins 19 and 21.
That is, for example, as shown in FIG. 10, the stage portions 7 and 9 are formed in a substantially rectangular plate shape, and the stage portions 7 and 9 and the leads 17 are connected by individual connecting portions 19 and 21. It doesn't matter.
Further, the connecting portions 19 and 21 are not limited to being formed one by one at the tip of each lead 17 connected to the stage portions 7 and 9, but, for example, as shown in FIG. They may be formed so as to be connected to the stage portions 7 and 9 together.

In the above-described configuration, the stage portions 7 and 9 are formed in a substantially rectangular shape in plan view. However, the present invention is not limited to this, and at least the magnetic sensor chips 3 and 5 are formed on the surfaces 23a and 23a of the stage portions 7 and 9, respectively. What is necessary is just to be formed in 25a so that adhesion | attachment is possible. That is, the stage portions 7 and 9 may be formed in, for example, a circle or an ellipse in a plan view, or may be provided with a hole penetrating in the thickness direction or formed in a mesh shape. .
9 to 11, the adjacent lead described in FIGS. 7 and 8 is formed at the tip of the lead 15 arranged in the direction of the reference axis L1 together with the lead 17 connected to the stage portions 7 and 9. You may provide the same thing as 45.

In addition, although the insulating films 31 and 33 having the fixing layer formed on the front surface and the back surface are used, this is not limited to the case where the thickness dimension of the fixing layer and the adhesive is not taken into account. The stage portions 7 and 9 and the magnetic sensor chips 3 and 5 may be bonded.
Further, the protruding pieces 35, 37, 47 are not limited to being formed at the end portions of the stage portions 7, 9 and the adjacent leads 45 facing each other, but protrude at least toward the back surfaces 23 d, 25 d of the stage portions 7, 9. It only has to be.
The stage portions 7 and 9 and the adjacent leads 45 are inclined using the protruding pieces 35, 37, and 47. However, the present invention is not limited to this, and at least at the stage where the magnetic sensor 40 has been manufactured, The two magnetic sensor chips 3 and 5 and the adjacent leads 45 may be inclined.

  Furthermore, in the embodiment of the present invention, the description is applied to the magnetic sensor 40 that detects the magnetic direction in the three-dimensional space. However, the present invention is not limited to this, and a physical quantity that measures at least the orientation and direction in the three-dimensional space Any sensor may be used. Here, the physical quantity sensor may be, for example, an acceleration sensor equipped with an acceleration sensor chip that detects the magnitude and direction of acceleration instead of the magnetic sensor chip.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

It is a top view showing a lead frame concerning one embodiment of the present invention. FIG. 2 is a side cross-sectional view showing a state where the magnetic sensor chip is mounted on the lead frame of FIG. 1 and the magnetic sensor chip and the lead are electrically connected by a wire. FIG. 2 is a side sectional view showing a method for inclining a stage portion in the lead frame of FIG. 1. FIG. 2 is a side sectional view showing a method for inclining a stage portion in the lead frame of FIG. 1. It is a top view which shows the magnetic sensor manufactured using the lead frame of FIG. It is a sectional side view of the magnetic sensor of FIG. It is a top view which shows the state which mounted the magnetic sensor chip on the lead frame which concerns on other embodiment of this invention, and electrically connected the magnetic sensor chip and the lead | read | reed with the wire. It is GG arrow sectional drawing of FIG. It is a top view which shows the lead frame which concerns on other embodiment of this invention. It is a sectional side view which shows the magnetic sensor which concerns on other embodiment of this invention. It is a sectional side view which shows the magnetic sensor which concerns on other embodiment of this invention. It is a top view which shows an example of the conventional lead frame.

Explanation of symbols

1, 42, 46 ... lead frame, 3, 5 ... magnetic sensor chip (physical quantity sensor chip), 7, 9 ... stage portion, 11 ... frame portion, 15, 17 ... lead, 19, 21 ... connecting portion, 23, 25 ... extension lead, 23a, 25a ... surface, 26, 28 ... protruding lead (exposed lead) 27, 29 ... protruding lead, 31, 33 ... Insulating film, 40 ... Magnetic sensor (physical quantity sensor), 43 ... First lead, 44 ... Second lead, L1, L2 ... Reference axis

Claims (7)

It consists of a metal thin plate having a stage part on which a physical quantity sensor chip is placed, a frame part having a plurality of leads arranged around it, and a connecting part for connecting at least one of the leads and the stage part,
The connecting portion has an easily deformable portion that inclines the stage portion around a reference axis with respect to the frame portion,
A lead frame, wherein a sheet-like insulating film made of an insulating material is disposed on a surface of a stage portion on which the physical quantity sensor chip is placed. Two stage parts are arranged inside the same frame part,
The lead frame according to claim 1, wherein a projecting lead projecting toward the other stage portion is formed on one stage portion.   3. The lead frame according to claim 1, wherein the stage portion and the connecting portion are constituted by extension leads extending from tips of the leads connected to the stage portion. 4. The stage portion is formed from a plurality of the extension leads,
The lead frame according to claim 3, wherein an exposed lead disposed in a region not overlapping with the physical quantity sensor chip is formed at a tip of each extension lead. A plurality of the leads includes a first lead connected to the stage part via the connecting part, and a second lead arranged in the direction along the reference axis together with the first lead,
An adjacent lead extending from the tip of the second lead through the reference axis is formed on the second lead,
The adjacent leads are arranged side by side with the stage portion in a direction along the reference axis, and are formed so as to be tiltable by moving around the reference axis with respect to the frame portion. The lead frame according to any one of claims 1 to 4.   The lead frame according to any one of claims 1 to 5, wherein a fixing layer is formed on a front surface and a back surface of the insulating film. A physical quantity sensor comprising the stage, the physical quantity sensor chip, and a plurality of the leads fixed integrally using the lead frame according to any one of claims 1 to 6. .

Images