JP2000227439A - Semiconductor dynamic quantity sensor, and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an extension dimension of a bonding wire for connecting electrically a space between a circuir chip and a sensor chip from getting long excessively, in the case where the sensor chip is arranged on the ciurcuit chip. SOLUTION: A sensor chip 1 having one-dimensional dynamic quantity detecting axis X parallel to a chip main surface is mounted on a chip mounting area 27 set on a circuit chip 19. The mounting area 27 is set as an area to mount selectively the sensor chip 1 in a condition where the sensor chip 1 is directed to either of the first direction in which the detecting axis X of the sensor chip 1 forms 45 deg. with respect to a reference edge part SE of the circuit chip 19 and the second direction (each direction forming 0 deg. or 90 deg.) different from the first direction. Plural electrode pads 28 connected via electrode pads 3b, 6c, 7c, 13a in a sensor chip 1 side and bonding wires 24 are provided in positions adjacent to the chip mounting area 27 in the circuit chip 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor dynamic quantity sensor having a sensor chip, a circuit chip for electrically processing signals from the sensor chip, and a method of manufacturing the same.

[0002]

For example, in a semiconductor acceleration sensor used for a vehicle airbag or the like,
A sensor chip for generating a signal corresponding to the magnitude of the acting acceleration, and a circuit chip for electrically processing a signal from the sensor chip are housed in a ceramic package provided with external terminals. Is mounted on a printed circuit board and mounted on a vehicle. In this case, it is generally assumed that the sensor chip and the circuit chip and the circuit chip and the package are electrically connected via bonding wires. Has become. In such a semiconductor acceleration sensor, when the sensor chip and the circuit chip are arranged side by side in a package, a package having a large mounting area is required, and it is inevitable that the entire size is increased. There are circumstances. For this reason, conventionally, it has been considered to adopt a configuration in which sensor chips are mounted in a stacked manner on a circuit chip, thereby reducing the size of the whole.

When the above-described semiconductor acceleration sensor is applied to, for example, a side airbag, it is necessary to detect not only the acceleration applied in the front direction of the vehicle but also the acceleration applied in the side direction. It has been necessary to mount the two packages on the board by appropriately changing the board mounting direction (position) so that the acceleration detection axis of the chip is oriented. In this case, the design of the wiring formed on the substrate side becomes complicated, and in some cases, the area for the wiring needs to be increased. Therefore, even when the acceleration detection axes are different, the board can be mounted on the board without changing the package mounting direction with respect to the board. In other words, the acceleration detection axes set on the sensor chip can be arbitrarily and easily set in the package. It is desired to be able to change to.

However, as described above, the sensor chip is mounted on the circuit chip in a stacked manner to reduce the overall size. In view of the above demand, the orientation of the sensor chip is simply changed and the acceleration is changed. If the direction of the detection axis is to be changed, the distance between the electrode pad on the sensor chip and the electrode pad on the circuit chip will change, so that the extended dimension of the bonding wire becomes extremely long in some cases. Sometimes. In such a state, the acceleration detection characteristics may be deteriorated due to the possibility that the bonding wires are dripped and short-circuited, or if the sensor chip is a capacitance detection type, the wire length is increased, and the stray capacitance or parasitic capacitance is caused by the influence. Problems come up. In order to cope with such a problem, it has been considered to integrate the sensor chip and the circuit chip into one chip. However, such a configuration complicates the manufacturing process and increases the cost. The new problem that rises.

The present invention has been made in view of the above circumstances, and in a semiconductor dynamic quantity sensor in which a sensor chip is arranged on a circuit chip, when a direction of a dynamic quantity detection axis is changed, an extension dimension of a bonding wire is indeterminate. It is an object of the present invention to provide a semiconductor dynamic quantity sensor which does not become too long and a method for manufacturing the same.

[0006]

To achieve the above object, the means described in claim 1 can be adopted. According to this means, since the sensor chip is mounted on the chip mounting area provided on the circuit chip, the area occupied by the sensor chip and the circuit chip can be reduced, and the overall size can be reduced. become. In addition, the chip mount area is provided at least with a predetermined physical quantity detection axis of the sensor chip.
Any one of the first direction and the second direction different from the first direction.
The electrode pad on the circuit chip side, that is, the electrode pad electrically connected to the electrode portion on the sensor chip side via a bonding wire, is set as an area that can be selectively mounted on one side. Since the sensor chip is arranged so as to be close to the electrode portion on the sensor chip side in accordance with all mounting states to be selected, there is no danger that the extended dimension of the bonding wire becomes unnecessarily long, and furthermore, dynamics The direction of the quantity detection axis can be easily changed. Furthermore, since it is only necessary to prepare a plurality of types of circuit chips in a state where the layout of the chip mount area and the electrode pads is changed, a rise in cost can be suppressed.

According to the second aspect of the present invention, a plurality of electrode pads, each including a plurality of electrode pads, are arranged on the circuit chip side so as to surround the chip mount area. When the chip is mounted on the chip mounting area such that the physical quantity detection axis is oriented in one of the first direction and the second direction, the electrode portion on the sensor chip side It suffices to connect the electrode pad group and the electrode pad group located at a distance close to this by a bonding wire. As a result, the direction of the physical quantity detection axis can be easily changed, and even if such a change is made, there is no possibility that the extension dimension of the bonding wire will be lengthened unnecessarily.
Further, although the structure of the circuit chip becomes complicated, it is possible to prevent a rise in cost as much as possible because only one kind of circuit chip is required.

According to the third aspect of the present invention, since the ring-shaped electrode pads are arranged concentrically on the circuit chip side so as to surround the chip cap region, the sensor chip detects the physical quantity of the sensor chip. When the sensor is mounted on the chip mount area in a state where the direction of the axis is set to an arbitrary direction, the electrode portion on the sensor chip side and the electrode pad can be connected in the shortest distance by a bonding wire. As a result, the direction of the physical quantity detection axis can be easily changed, and the extension dimension of the bonding wire can be minimized. Further, although the structure of the circuit chip becomes complicated, it is possible to prevent a rise in cost as much as possible because only one kind of circuit chip is required.

In order to achieve the above object, a manufacturing method according to claim 6 can be adopted. According to this manufacturing method, at least a first direction or a second direction different from the first direction is provided on a surface of a circuit chip for electrically processing a signal from a sensor chip having a predetermined physical quantity detection axis. After forming a chip mount area and a plurality of electrode pads on which the sensor chip can be selectively mounted so that the physical quantity detection axis is oriented in the direction of, the physical quantity detection axis is The sensor chip is mounted in a state where the direction of the sensor chip is adjusted to one of the first direction and the second direction. Then, among the plurality of electrode pads of the circuit chip, an electrode pad close to the electrode portion of the sensor chip is selected, and the electrode portion and the selected electrode pad are connected by a bonding wire.

Therefore, since the sensor chip is mounted on the chip mounting area provided on the circuit chip, the area occupied by the sensor chip and the circuit chip can be reduced, and the overall size can be reduced. .
In this case, the chip mount area formed on the surface of the circuit chip has at least the first physical quantity detection axis of the sensor chip.
Or the sensor chip can be selectively mounted so as to face a second direction different from the first direction. When connecting to the electrode pad with a bonding wire, one of the plurality of electrode pads of the circuit chip that is close to the electrode portion of the sensor chip is selected and connected. The direction can be easily changed, and the extension of the bonding wire does not have to be lengthened unnecessarily, so that smooth wire bonding can be performed.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment in which the present invention is applied to a capacitive semiconductor acceleration sensor and a method of manufacturing the same will be described below with reference to FIGS. FIG. 5 shows a planar structure of a sensor chip 1 for a semiconductor acceleration sensor (however, the hatched band in FIG. 5 does not show a cross section, and is used to make it possible to easily recognize the distinction between structural elements. FIG. 6 shows a schematic cross-sectional structure along the line AA in FIG.

In FIGS. 5 and 6, a support substrate 2 (shown only in FIG. 6) made of, for example, single-crystal silicon is formed in a square shape having a rectangular opening 2a. A single-crystal silicon layer 3 having a relatively low specific resistance due to impurity diffusion;
(Shown only in FIG. 6). In this single-crystal silicon layer 3, a beam structure 5 and a pair of fixed electrode structures 6, 7 are formed using a micromachining technique.

The beam structure 5 has a structure in which both ends of a rectangular rod-shaped mass 8 are integrally connected to anchors 10a and 10b via rectangular frame-shaped beams 9a and 9b. The portions 10 a and 10 b are supported on the opposite sides of the support substrate 2 via the insulating film 4. Thereby, the mass portion 8 and the beam portions 9a and 9b are
It is in a state facing the opening 2a of the support substrate 2. In this case, the acceleration detection axis (corresponding to the physical quantity detection axis in the present invention) of the sensor chip 1 is a one-dimensional direction parallel to the main surface of the sensor chip 1, and the beam portions 9a and 9b are When receiving acceleration including a component of the acceleration detection axis of the sensor chip 1 indicated by an arrow X in FIG. 5, the mass unit 8 is displaced in the direction, and is restored to the original state according to the disappearance of the acceleration. It has a configuration with a spring function.

Further, the beam structure 5 includes a plurality of movable electrodes 11a and 11b integrally protruding from both side surfaces of the mass portion 8 in a direction orthogonal to the mass portion 8,
These movable electrodes 11a and 11b also face the opening 2a of the support substrate 2. Note that these movable electrodes 1
Although 1a and 11b are actually provided in large numbers, only two are shown in FIG. 5 for simplification. The movable electrodes 11a and 11b are each formed in a rod shape having a rectangular cross section, and a plurality of rectangular through holes 12 are formed. The plurality of rectangular frame members are linearly connected by the through holes 12. It has a shape having a so-called ramen structure in the form described above.

A movable electrode wiring portion 13 integrally formed with one anchor portion 10b of the beam structure 5 is formed on the support substrate 2 via the insulating film 4. An electrode pad 13a for wire bonding (corresponding to an electrode portion in the present invention) is formed of, for example, aluminum at a predetermined position on the sensor chip 13, specifically at a portion near the edge of the sensor chip 1.

The fixed electrode structure 6 includes a fixed electrode wiring portion 6 a formed on the support substrate 2 via the insulating film 4,
One side surface of the movable electrode 11a and a plurality of first fixed electrodes 6b arranged in parallel with a predetermined detection gap are provided integrally with each other.
“b” is in a state supported by the fixed electrode wiring portion 6a in a cantilever manner. As a result, the first fixed electrode 6b faces the opening 2a of the support substrate 2.

The fixed electrode structure 7 includes a fixed electrode wiring portion 7 formed on the support substrate 2 with the insulating film 4 interposed therebetween.
a and a plurality of second fixed members arranged in parallel with one side surface of the movable electrode 11b (the surface of the movable electrode 11a opposite to the detection gap side) with a predetermined detection gap. It is configured to have the electrode 7b integrally,
Each fixed electrode 7b is in a state of being cantilevered by the wiring portion 7a. Thus, the second fixed electrode 7b faces the opening 2a of the support substrate 2.

The first and second fixed electrodes 6b and 7b are actually provided in large numbers.
FIG. 5 shows only two pieces for simplification. Also,
Each of the first and second fixed electrodes 6b and 7b is formed in a rod shape having a rectangular cross section, and a plurality of rectangular through holes 14 are formed. The shape has a so-called ramen structure in a form of linear connection. Further, the fixed electrode wiring section 6
Electrode pads 6c and 7c (corresponding to the electrode portions in the present invention) for wire bonding are formed of aluminum at predetermined positions on a and 7a, specifically at a portion near the edge of the sensor chip 1. .

The single crystal silicon layer 3 remaining on the periphery of the support substrate 2 functions as a shielding thin film 3a, and is adjacent to the shielding thin film 3a, the beam structure 5, and the movable electrode wiring portion 13. Insulated trench 15
Are formed, and the shielding thin film 3a and the fixed electrode wiring portion 6 are formed.
Isolation trenches 16 and 17 are respectively formed at adjacent portions to a and 7a. An electrode pad 3b for wire bonding (corresponding to an electrode portion in the present invention) is formed of aluminum at a position near the edge of the sensor chip 1 on the shielding thin film 3a.

In the sensor chip 1 configured as described above, when an acceleration including a component in the direction of the acceleration detection axis X indicated by an arrow in FIG. The displacement amount according to the acceleration depends on the mass of the mass portion 8 and the restoring force of the beam portions 9a and 9b, and the movable electrodes 11a and 1a in the voltage applied state.
1b and the first and second fixed electrodes 6b and 7b. In this case, a first capacitor is formed between the movable electrode 11a and the first fixed electrode 6b, and a second capacitor is formed between the movable electrode 11b and the second fixed electrode 7b. And the respective capacitances of the first and second capacitors are:
As described above, it changes differentially according to the displacement of the movable electrodes 11a and 11b when the acceleration acts on the mass portion 8. Therefore, the acceleration can be detected by extracting such a change in the capacitance as a change in the amount of charge through the electrode pads 6c, 7c, and 13a.

FIG. 4 shows a semiconductor acceleration sensor (semiconductor dynamic quantity sensor) 1 including the sensor chip 1.
8 shows a schematic longitudinal sectional structure. In FIG. 4, the sensor chip 1 is mounted on a circuit chip 19 for electrically processing a signal from the sensor chip 1, and is integrated with the sensor chip 1 and the circuit chip 19. An object is accommodated in a concave portion 20a formed in a case-shaped package 20 having an external terminal (not shown), and the concave portion 20a is hermetically sealed by a lid 21. That is, the sensor chip 1
The circuit chip 19 is adhered to the package 20 via the flexible adhesive 22, and the circuit chip 19 is adhered to the package 20 via the flexible adhesive 23. in this case,
The sensor chip 1 and the circuit chip 19 and the circuit chip 19 and the package 20 are electrically connected via bonding wires 24 and 25, respectively.
Further, the lid 21 is attached to the package 20 via a metal seal ring 26 as described later.

The relationship between the sensor chip 1 and the circuit chip 19 will be specifically described below. 1 (a) to 3 (a) are plan views of the circuit chip 19, and FIGS. 1 (b) to 3 (b) show the mounting of the sensor chip 1 on the circuit chip 19. The plan view of the state shown is shown. However, FIGS. 1 to 3
Is the layout of the electrode pads for wire bonding,
This is a schematic diagram illustrating only the bonding wire 24 and the acceleration detection axis X of the sensor chip 1.

That is, the circuit chip 19 includes the sensor chip 1
A chip mount area 27 having a square shape for mounting the sensor pad in a mounting state, the electrode pads 3b of the sensor chip 1,
6c, 7c and 13a and four electrode pads 28 connected via the bonding wires 24, package 2
A plurality (for example, thirteen) connected to an electrode pad group (not shown) of the device 0 via the bonding wire 25.
FIG. 1A, FIG.
(A), as shown in FIG. 3 (a), three types in which the chip mount area 19a and the electrode pads 19b and 19c are provided in different layouts are prepared. Therefore, the layout of each circuit chip 19 will be described below. In the following description, for convenience, the circuit chip 19 in FIG. 1A is denoted by a suffix A, and the circuit chip 19 in FIG.
, A subscript B, and a subscript C to the circuit chip 19 in FIG.

The circuit chip 19A shown in FIG. 1A has a state in which a predetermined edge 27a of the chip mount area 27 has an angle of 45 ° with the reference edge SE of the circuit chip 19A, in other words, a sensor. The chip 1 is arranged so that the physical quantity detection axis X of the chip 1 is oriented in a direction (first direction) at 45 ° with respect to the reference edge SE, and a sensor chip is provided in a region along the edge 27a. The three electrode pads 28 that are in close proximity to the one-side electrode pads 6c, 13a, and 7c, respectively, are arranged in a line.
In the chip mounting area 27, one electrode pad 28 which is in a state close to the electrode pad 3b on the sensor chip 1 side is arranged in a region along the edge part 27b facing the edge part 27a.

The circuit chip 19B shown in FIG. 2A has a state in which a predetermined edge 27a of the chip mount area 27 is parallel to the reference edge SE of the circuit chip 19B (an angle of 0 ° with the reference edge SE). In other words, the sensor chip 1 is arranged so that the physical quantity detection axis X of the sensor chip 1 is oriented in a direction (second direction) at which the axis X is 90 ° with respect to the reference edge SE. Edge 27a
The electrode pad 6c on the sensor chip 1 side
The three electrode pads 28 that are in close proximity to 13a and 7c, respectively, are arranged in a line. Further, in the chip mounting area 27, along the edge 27b facing the edge 27a, the sensor chip 1 One electrode pad 28 that is in close proximity to the electrode pad 3b is arranged.

The circuit chip 19C shown in FIG. 3A has a state in which a predetermined edge 27a of the chip mount area 27 is orthogonal to the reference edge SE of the circuit chip 19C (an angle of 90 ° with the reference edge SE). In other words, the sensor chip 1 is arranged so that the physical quantity detection axis X of the sensor chip 1 is oriented in a direction (a second direction) at which it is 0 ° with respect to the reference edge SE. Edge 27a
The electrode pad 6c on the sensor chip 1 side
The three electrode pads 28 that are in close proximity to 13a and 7c, respectively, are arranged in a line. Further, in the chip mounting area 27, along the edge 27b facing the edge 27a, the sensor chip 1 One electrode pad 28 that is in close proximity to the electrode pad 3b is arranged.

When the sensor chip 1 is mounted on the chip mounting area 27 of the circuit chip 19, the acceleration detection axis X of the sensor chip 1 and the reference edge SE of the circuit chip 19 are selected from the circuit chips 19A, 19B and 19C. Is selected corresponding to the detection angle (any of 45 °, 0 °, and 90 °) set between the above.

FIG. 7 is a schematic sectional view showing a manufacturing procedure of the semiconductor acceleration sensor 18, which will be described below.

That is, first, as shown in FIG. 7A, a liquid flexible adhesive 22 is applied to the lower surface of the sensor chip 1, and then, as shown in FIG. The chip 1 is mounted and adhered to the chip mount area 27 of the circuit chip 19 selected as described above in a state of conforming to the shape. Next, as shown in FIG. 7 (c), a liquid flexible adhesive 23 is applied to the lower surface of the circuit chip 19, and thereafter, as shown in FIG. 7 (d), the circuit chip 19 and the sensor chip 1 is inserted into the recess 2 of the package 20 to which the seal ring 26 is attached, for example, by brazing.
0a and mounted.

When performing each of the above bonding steps,
A configuration in which the flexible adhesive 22 is applied to the chip mount region 27 side, or the circuit chip 1 in the concave portion 20a
A configuration is also possible in which the flexible adhesive 23 is applied to the mounting region side of the substrate 9. In addition, liquid adhesives are used as the adhesives 22 and 23, but various adhesives such as a sheet, a solid, and a gel may be used.

Thereafter, as shown in FIG. 7E, the electrode pads 3b, 6c, 7c, 13a of the sensor chip 1 are formed.
(See FIGS. 1 to 3) and the electrode pads 28 of the circuit chip 19
Bonding wires 24 between the group (see FIGS. 1 to 3);
And the package 20 is connected to the electrode pads 29 of the circuit chip 19 (see FIGS. 1 to 3).
And an electrode pad group (not shown) on the side is electrically connected by a bonding wire 25. The order of the bonding may be either order. Then, as shown in FIG. 7F, the lid 21 is placed on the seal ring 26, and the gap between the lid 21 and the seal ring 26 is hermetically sealed by a seam welding method, thereby completing the semiconductor acceleration sensor 18.

According to the configuration of the present embodiment, the sensor chip 1 is mounted on the chip mount area 27 provided on the circuit chip 19, so that the sensor chip 1 and the circuit chip 19 occupy the sensor chip 1. The area can be reduced. Accordingly, the mounting area required for the package 20 can be reduced, and the size of the package 20 can be reduced, so that the size of the entire sensor can be reduced.

Further, among the three types of circuit chips 19 (19A, 19B, 19C) having different layouts of the chip cloak region 27 and the electrode pads 28 and 29, the electrode pads 3b on the sensor chip 1 side mounted thereon are selected. , 6c,
Electrode pad 28 arranged close to 7c, 13a
Since one having a group is selected and used, a bonding wire 24 for electrically connecting between the electrode pads 3b, 6c, 7c, 13a and the four electrode pads 28 is used.
There is no danger that the length of the extension will become unnecessarily long. As a result, there is no danger that the bonding wire 24 hangs down and short-circuits with other bonding wires 24, etc., and floating caused by extension of the wire length, which is a problem when the sensor chip 1 is of the capacitance detection type as in this embodiment. It is possible to prevent the acceleration detection characteristics from being deteriorated due to the influence of the capacitance and the parasitic capacitance.

Further, according to the selection of the type of the circuit chip 19 as described above, the angle between the physical quantity detection axis X of the sensor chip 1 and the reference edge SE of the circuit chip 19 is set to 45 degrees.
Since the angle can be changed to any one of 0 °, 0 °, and 90 °, the change of the direction of the physical quantity detection axis X (change of the absolute positional relationship between the acceleration detection axis X and the package 20) can be arbitrarily and easily performed. Become like As a result, when the semiconductor acceleration sensor according to the present embodiment is used for an airbag, for example, 2
Without changing the mounting direction of the above package 20,
In response to the requirement that the orientation of the sensor chip 1 is arbitrarily and easily changed so that the acceleration detection axis of the sensor chip 1 is oriented in each of the detection directions such as the acceleration applied in the front direction and the acceleration applied in the side direction of the vehicle, and mounted on the board. Will surely be able to respond. Also, as described above, the chip mount area 27
In addition, it is only necessary to prepare three types of circuit chips 19 in a state where the layout of the group of electrode pads 28 and 29 is changed, so that an increase in cost can be suppressed.

(Second Embodiment) FIGS. 8 and 9 show a second embodiment of the present invention. Only the portions different from the first embodiment will be described below. FIG. 8 is a plan view of the circuit chip 30 according to the present embodiment, and FIG. 9 is a plan view of a state where the sensor chip 1 is mounted on the circuit chip 30. However, FIGS. 8 and 9 are schematic diagrams illustrating only the layout of the electrode pads for wire bonding, the bonding wires and the acceleration detection axis X of the sensor chip 1.

That is, the circuit chip 30 has a circular chip mount area 31 for mounting the sensor chip 1 in the center of the upper surface thereof, and the electrode pads 3b, 6c, 7c of the sensor chip 1 And 13a connected to 4
For example, eight electrode pad groups each including one of the electrode pads 28 are arranged concentrically so as to surround the chip mount area, and are connected to an electrode pad group (not shown) included in a package around them. The layout is such that a plurality of electrode pads 29 are arranged. still,
The circuit chip 30 can use a multilayer wiring, and in such a case, the inner wiring can be used for the wiring from the electrode pad 28.

When the sensor chip 1 is mounted on the chip mounting area 31 of the circuit chip 30, the angle between the acceleration detection axis X of the sensor chip 1 and the reference edge SE of the circuit chip 30 is set arbitrarily. FIG. 9 (a),
(B) As shown in (c), connecting between the electrode pads 3b, 6c, 7c and 13a on the sensor chip 1 side and the group of electrode pads 28 which is the closest to the electrode pads 3b, 6c, 7c and 13a. become. In addition, FIG.
(B) and (c) show the acceleration detection axis X and the reference edge SE.
Are set to 45 °, 0 °, and 90 °, respectively, but the angles can be arbitrarily set in the range of 0 ° to 360 °.

According to this embodiment having such a configuration,
Since the direction of the acceleration detection axis X can be easily changed, the sensor chip 1 is mounted so that the acceleration detection axes of the sensor chip 1 are oriented in a plurality of detection directions without changing the mounting direction of the two or more packages 20. It is possible to reliably meet the demand for arbitrarily and easily changing the direction of mounting on a substrate. In addition, even when the direction of the acceleration detection axis X is changed, there is no possibility that the extension dimension of the bonding wire 24 becomes unnecessarily long, so that the bonding wire 24 hangs down and short-circuits with another bonding wire 24 or the like. In addition to eliminating the fear, it is possible to prevent the acceleration detection characteristics from deteriorating due to the influence of stray capacitance or parasitic capacitance due to the extension of the wire length. Further, although the structure of the circuit chip 30 becomes complicated,
Since only one type of circuit chip 30 is required, a rise in cost can be prevented as much as possible.

(Third Embodiment) FIG. 10 shows a third embodiment of the present invention.
Only parts different from the embodiment will be described. FIG. 10 is a plan view showing a state where the sensor chip 1 is mounted on the circuit chip 32 according to the present embodiment. However, FIG. 10 is a schematic diagram illustrating only the layout of the electrode pads for wire bonding, the bonding wires, and the acceleration detection axis X of the sensor chip 1. Further, the hatched band in FIG. 10 does not show a cross section, but is for making it possible to easily recognize the distinction of each electrode pad. That is, the circuit chip 32 has the sensor chip 1 mounted on the center of the upper surface thereof. Circular chip mount area (not shown) for mounting
And the electrode pads 3b and 6 of the sensor chip 1.
Four electrode pads 33 connected to c, 7c and 13a
Are formed in rings of different sizes surrounding the chip mount area, and are arranged concentrically with each other. The circuit chip 30
Can use a multilayer wiring, and the electrode pad 3
The wiring for 3 will use the inner layer wiring.

When the sensor chip 1 is mounted in the chip mounting area of the circuit chip 32, the angle between the acceleration detection axis X of the sensor chip 1 and the reference edge SE of the circuit chip 32 is arbitrarily set. In such a mounted state, as shown in FIG. 10, the electrode pads 3b, 6c, 7c and 1 on the sensor chip 1 side.
The connection between 3a and the four electrode pads 33 can be made in the shortest distance by the bonding wire 24.

According to the present embodiment having such a configuration, the direction of the acceleration detection axis X can be easily changed. Therefore, two or more packages 20 can be mounted in a plurality of detection directions without changing the mounting direction. Thus, it is possible to reliably respond to a request to arbitrarily and easily change the orientation of the sensor chip 1 so that the acceleration detection axis of the sensor chip 1 is oriented and mount the sensor chip 1 on a substrate. Moreover, even when the direction of the acceleration detection axis X is changed, the extension dimension of the bonding wire 24 can be minimized, so that there is no danger that the bonding wire 24 hangs down and short-circuits with another bonding wire 24 or the like. In addition, it is possible to prevent the acceleration detection characteristic from being deteriorated due to the influence of stray capacitance or parasitic capacitance caused by extension of the wire length. In addition, although the structure of the circuit chip 32 is complicated, it is only necessary to prepare one kind of circuit chip 32, so that a rise in cost can be prevented as much as possible.

(Other Embodiments) The present invention is not limited to the above-described embodiment, but can be modified or expanded as follows. In the first embodiment, three layouts such as the electrode pads of the circuit chip 19 are used.
Various types of layouts can be set so as to cope with various changes in the angle between the physical quantity detection axis X of the sensor chip 1 and the reference edge SE of the circuit chip 19. The present invention can be widely applied not only to the semiconductor acceleration sensor but also to other semiconductor dynamic quantity sensors such as a yaw rate sensor. In each of the above embodiments, the sensor chip 1 has one detection axis. However, the present invention can be applied to a sensor chip having a plurality of one-dimensional detection axes on the same chip surface.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a circuit chip showing a first embodiment of the present invention and a schematic plan view with a sensor chip mounted on the circuit chip, part 1

FIG. 2 is a schematic plan view of a circuit chip and a schematic plan view with a sensor chip mounted on the circuit chip, part 2

FIG. 3 is a schematic plan view of a circuit chip and a schematic plan view of a state where a sensor chip is mounted on the circuit chip.

FIG. 4 is a schematic longitudinal sectional view of a semiconductor acceleration sensor.

FIG. 5 is a plan view of a sensor chip.

FIG. 6 is a schematic cross-sectional view taken along line AA in FIG.

FIG. 7 is a schematic sectional view showing a manufacturing procedure.

FIG. 8 is a schematic plan view of a circuit chip showing a second embodiment of the present invention.

FIG. 9 is a schematic plan view in a state where a sensor chip is mounted on a circuit chip.

FIG. 10 is a schematic plan view showing a third embodiment of the present invention with a sensor chip mounted on a circuit chip.

[Explanation of symbols]

1 is a sensor chip, 3b, 6c, 7c and 13a are electrode pads (electrode portions), 6b is a first fixed electrode, 7b is a second fixed electrode, 11a and 11 are movable electrodes, and 18 is a semiconductor acceleration sensor (semiconductor). Mechanical quantity sensor), 19, 19A, 19
B and 19C are circuit chips, 20 is a package, 24 and 2,
5 is a bonding wire, 27 is a chip mounting area,
28 and 29 are electrode pads, 30 is a circuit chip, 31 is a chip mounting area, 32 is a circuit chip, and 33 is an electrode pad.

Claims (7)

[Claims] 1. A sensor chip having a predetermined physical quantity detection axis and having an electrode portion, a chip mount area for mounting the sensor chip, and electrically connected to the electrode portion via a bonding wire. A semiconductor chip provided with an electrode pad and a circuit chip for electrically processing a signal from the sensor chip, wherein a chip mount region in the circuit chip has at least a first And a second direction different from the first direction is set as an area where the sensor chip can be selectively mounted, and the electrode pad in the circuit chip is selected by the sensor chip. Characterized in that the sensor is arranged so as to be close to the electrode portion on the sensor chip side in accordance with all mounting states to be performed. 2. A method according to claim 1, wherein a plurality of electrode pads are provided, and a plurality of electrode pads are arranged so as to surround the chip mount area, and the sensor chip is mounted on the chip mount area. 2. The semiconductor dynamic quantity sensor according to claim 1, wherein the electrode portion on the sensor chip side and an electrode pad group located close to the electrode portion can be connected by the bonding wire. 3. The semiconductor dynamic quantity sensor according to claim 1, wherein the plurality of electrode pads are each formed in a ring shape surrounding the chip mount area, and are arranged concentrically with each other. . 4. The sensor chip includes a movable electrode that is displaced in response to the action of a physical quantity, and a fixed electrode that is disposed to face the movable electrode with a predetermined gap therebetween. 4. The semiconductor dynamic quantity sensor according to claim 1, wherein the sensor is configured as a capacitance type sensor that takes out a change in capacitance of a capacitor formed between fixed electrodes. 5. The semiconductor dynamic quantity sensor according to claim 1, further comprising a package for accommodating the sensor chip and the circuit chip. 6. A method of manufacturing a semiconductor dynamic quantity sensor comprising: a sensor chip having a predetermined physical quantity detection axis; and a circuit chip for electrically processing a signal from the sensor chip. A chip mount area and a plurality of electrode pads on the surface, on which the sensor chip can be selectively mounted so that the physical quantity detection axis is oriented in at least a first direction or a second direction different from the first direction. Forming the physical quantity detection axis in the first direction and the second direction.
The sensor chip is mounted on the chip mount area in accordance with any one of the directions, and an electrode pad close to an electrode portion of the sensor chip is selected from among a plurality of electrode pads of the circuit chip, and the electrode is selected. A method for manufacturing a semiconductor dynamic quantity sensor, comprising: connecting a portion and the selected electrode pad with a bonding wire. 7. The method according to claim 6, wherein the integrated sensor chip and the circuit chip are housed in a package before or after the bonding of the bonding wire.