JPH11211750A - Semiconductor sensor and package for semiconductor sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a mount area for a semiconductor sensor, prevent mechanical and induced noises resulting from a wiring and decrease mount costs. SOLUTION: A package 20 stores a semiconductor sensor chip 10. A main face of the package to which the semiconductor sensor chip 10 is mounted is constituted to have a predetermined angle to a face of a printed board 40 loading the package 20. A plurality of terminals are provided at two confronting sides of the main face to connect input/output terminals of the semiconductor sensor chip 10. A plurality of pins 22 are set along two sides parallel to the two sides of the main face at a bottom face perpendicular to the main face to be inserted into mount holes formed in the printed board 40. The plurality of terminals and the plurality of pins 22 at the parallel sides are electrically connected with each other along two side faces via the main face.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor sensor package for housing a semiconductor sensor chip used for medical, automotive, measuring, and calibration purposes and a semiconductor sensor chip for detecting an acting physical quantity, and more particularly to an acceleration sensor. The present invention relates to a semiconductor sensor and a semiconductor sensor package for measuring a physical quantity acting vertically on a surface of a semiconductor sensor chip.

[0002]

2. Description of the Related Art FIG. 19 shows an example of a conventional semiconductor sensor. In this conventional example, an acceleration sensor chip 5 for detecting acceleration in a direction 700 perpendicular to the surface of the chip 5
00 is mounted on the printed circuit board 800 such that the vertical direction of the chip surface 501 correctly matches the acceleration direction 700. More specifically, the package 600 accommodating the acceleration sensor chip 500 is fixed to the high rigid support substrate 900 with the sensor chip fixing pins 910, and the high rigid support substrate 900 is mounted on the printed circuit board. And the input / output terminals of the acceleration sensor chip (not shown)
The terminal 610 of the package electrically connected to the terminal 810 of the package and the terminal 810 of the printed wiring are connected by a wiring 820.
A configuration similar to the semiconductor acceleration sensor shown in FIG. 19 is disclosed in Japanese Patent Application Laid-Open No. 8-94663 (U.S. Application No. 08 / 189,9).
48) is described as a prior art.

As the acceleration sensor chip 500, for example, a sensor chip shown in FIG. 20 is used. The acceleration sensor chip 500 has four beams 510, a weight 520, and a support frame 530 that are formed from an integral silicon single crystal. Semiconductor strain gauges 540A to 540D are formed on the four beams 510, respectively, and these semiconductor strain gauges 540A to 540D are connected by aluminum wiring 550 to form a Wheatstone bridge. 560A and 560C are input terminals, 560B and 560D are output terminals. When acceleration is generated in the acceleration sensor chip 500 in a direction 700 perpendicular to the surface 501, the weight 520 is displaced in the direction of the acceleration, and the four semiconductor strain gauges 540A to 540 are formed.
D, 540A and 540C arranged on the weight side and 540B and 540D arranged on the support frame side always generate opposing resistance changes.
A and 540C are placed on opposite sides of the Wheatstone bridge and semiconductor strain gauges 540B and 540D
Are disposed on different opposite sides of the Wheatstone bridge, it is possible to obtain an output corresponding to the acceleration generated in the direction 700 perpendicular to the surface of the acceleration sensor chip 500.

[0004]

However, the above-mentioned conventional acceleration sensor has the following problems.

1) Since the package 600 of the acceleration sensor is mounted on the printed circuit board 800 via the support substrate 900 having high rigidity, the mounting area increases, and the dimensions of the entire acceleration measuring system including the printed circuit board 800 are reduced. growing.

2) The mechanical vibration of the wiring 820 is transmitted to the package of the sensor, and causes mechanical noise. Also,
Since the wiring 820 is located in the three-dimensional space, it is easy to induce external induced noise.

[0007] 3) Since there are steps which are difficult to automate, such as a step of fixing the package 600 to the support substrate 900 having high rigidity and a step of wiring the package 600 to the printed circuit board 800, the mounting cost is increased.

The present invention solves such a conventional problem, reduces a mounting area, prevents mechanical noise and inductive noise derived from wiring, and provides a semiconductor sensor and a semiconductor sensor package with low mounting cost. The purpose is to provide.

[0009]

In order to achieve the above-mentioned object, a semiconductor sensor according to the present invention comprises: a semiconductor sensor chip for detecting a physical quantity acting in a direction perpendicular to a surface of the chip; A package for accommodating, wherein a main surface for mounting the semiconductor sensor chip is formed at a predetermined angle with respect to a surface of a printed circuit board on which the package is mounted, and the main surface is formed along two opposite sides thereof. A plurality of terminals are provided for connection to the input / output terminals of the semiconductor sensor chip, and a plurality of pins are provided on a bottom surface perpendicular to the main surface along two sides parallel to the two sides of the main surface. A semiconductor sensor package provided to be inserted into a mounting hole formed in the printed circuit board and electrically connected to the plurality of terminals and the plurality of pins; It consists, and a plurality of terminals of input and output terminals and the package of the semiconductor sensor chip mounted on the main surface is electrically connected.

Here, the main surface for mounting the semiconductor sensor chip may be formed substantially perpendicular to the surface of the printed circuit board on which the package is mounted.

[0011] The semiconductor sensor chip may be a semiconductor acceleration sensor chip.

The semiconductor acceleration sensor chip comprises a sensor frame comprising a support frame, at least one displaceable weight, and a beam connecting the weight to the support frame. An acceleration sensor chip formed on the thin film silicon formed through the sensor structure, wherein the insulating layer between the sensor structure and the substrate silicon has been removed, and the beam portion has a plurality of parallel sets. An acceleration sensor chip comprising a beam, wherein the weight is connected to the support frame by the plurality of parallel beams, and at least two semiconductor strain gauges are formed on surfaces of the plurality of parallel beams. There may be.

[0013] The semiconductor acceleration sensor chip may include:
A sensor structure including a support frame, a displaceable weight having a magnetic thin film formed on the surface thereof, and a beam connecting the weight to the support frame is formed on the substrate silicon via an insulating layer. Formed in thin film silicon, wherein the insulating layer between the sensor structure and the substrate silicon has been removed;
The acceleration sensor chip may be configured such that a coil is formed on the support frame around the weight so as to surround the weight.

Further, the semiconductor acceleration sensor chip includes a support frame, a plurality of sensors each including a displaceable weight having a magnetic thin film formed on a surface thereof and a beam connecting the weight to the support frame. A structure is formed on the thin film silicon formed on the substrate silicon via the insulating layer,
The insulating layer between the plurality of sensor structures and the substrate silicon is removed, and a coil is formed around a weight on a support frame around the respective weight, and the plurality of coils are formed. May be acceleration sensor chips connected in series.

The semiconductor sensor chip may be a semiconductor angular acceleration sensor chip, wherein the semiconductor angular acceleration sensor chip includes a first supporting frame portion and a first displaceable magnetic thin film formed on a surface thereof. A plurality of first sensor structures each including a weight portion and a first beam portion connecting the first weight portion to the first support frame portion; a thin film silicon formed on a substrate silicon via an insulating layer; And wherein the insulating layer between the plurality of first sensor structures and the substrate silicon has been removed, and a first support frame portion around each of the first weight portions is provided on the first support frame portion. A first detection coil is formed surrounding each of the weights of the first and second sensors, and a first sensor group in which the plurality of first detection coils are connected in series; a second support frame; Displaceable second thin film formed Ri portions and a plurality of second comprising a weight portion of the second from the second beam portion connected to the second support frame portion
The sensor structure is formed on the thin film silicon formed on the substrate silicon via an insulating layer, the insulating layer between the plurality of second sensor structures and the substrate silicon has been removed, A second detection coil is formed on a second support frame around each of the second weights so as to surround the second weight, and the plurality of second detection coils are connected in series. And the second sensor group are formed on the same semiconductor chip, and the first sensor group and the second sensor group have the same number of sensor structures, and the first sensor group and the second sensor group have the same number. The groups are arranged symmetrically with respect to the detection axis, and when an angular acceleration occurs around the detection axis, a current flowing through the plurality of first and second detection coils of the first and second sensor groups is generated. Are in the same direction. First and second detection coils of the sensor group to form a closed loop, the plurality of first and second
An angular acceleration sensor chip comprising means for amplifying a signal from the detection coil and means for integrating an output from the plurality of detection coils to output an angular velocity signal.

A semiconductor sensor package according to the present invention is a package for accommodating a semiconductor sensor chip, wherein a main surface for mounting the semiconductor sensor chip has a predetermined angle with respect to a surface of a printed circuit board on which the package is mounted. The main surface is provided with a plurality of terminals for connection to input / output terminals of the semiconductor sensor chip along two opposing sides thereof, and the main surface is provided on a bottom surface perpendicular to the main surface. A plurality of pins are provided so as to be inserted into mounting holes formed in the printed circuit board along two sides parallel to the two sides of the printed circuit board, respectively, and the plurality of pins provided along the parallel sides are provided. The terminal and the plurality of pins are electrically connected along two side surfaces sandwiching the main surface.

Here, the main surface for mounting the semiconductor sensor chip may be formed substantially perpendicular to the surface of the printed circuit board on which the package is mounted.

It is preferable that wiring connecting the plurality of terminals and the plurality of pins is buried in the package.

[0019]

FIG. 1 shows a first embodiment of the present invention. 1A is a front view, FIG. 1B is a side view, and FIG.
FIG. 1C is a sectional view taken along the line aa in FIG.
FIG. 2D is a cross-sectional view taken along the line bb of FIG.
However, FIG. 1A shows a state where the lid 21 shown in FIG. 1C is removed.

For example, a package 2 made of epoxy resin
0 is a sensor fixing surface 20 for fixing the semiconductor sensor 10
A, a plurality of pins 22 arranged in parallel along two sides sandwiching the lid 21 and the sensor fixing surface 20A, projecting from the package bottom surface, and partially embedded in the package body.
And an acceleration sensor chip 1 on the sensor fixing surface 20A.
A plurality of wire bond pads 23 for supplying a current to 0 and extracting detection signals to the outside are formed.
Each of the wire bonding pads 23 is
Are connected to each other by a wiring 25. Actually, the wire bonding pad 23 and the wiring 25 can be formed by an integral thin metal plate. That is, a thin metal plate is punched into a desired shape, subjected to bending, adhered to the sensor fixing surface 20A and the side surface of the package, and connected to the pins 22 by soldering or the like. Furthermore, it is preferable from the viewpoint of wiring protection that the outer peripheral surface of the package is covered with an epoxy resin or the like and the wiring portion is embedded in the package. The semiconductor sensor chip 10 is fixed to the sensor fixing surface 20A of the package manufactured as described above with an adhesive or the like. The semiconductor sensor chip 10 has a direction 3 perpendicular to its surface.
It is a sensor chip that detects a physical quantity acting on 0, for example, acceleration. Then, the wire bond pads 23 are electrically connected to input / output terminals (not shown) of the semiconductor sensor chip 10. In this example, the connection indicates connection by wire bonding using the wire 24. Finally, the lid 21 is bonded to the package body. Thus, a semiconductor sensor is manufactured. This structure is similar to the package structure known as DIP (Dual Inline Package). As shown, each of the plurality of pins 22 is reliably and independently configured within the package 20 and is configured so as not to interfere with each other. Further, since the wiring 25 is embedded in the package, it does not vibrate. Further, since the package 20 is sealed by the lid 21, the semiconductor sensor chip 10 is not exposed to an external environment.

The semiconductor sensor packaged with the semiconductor sensor chip as described above is mounted on a printed circuit board in the same manner as a normal IC component. FIG. 2 is a view for explaining the state of mounting, and shows a cross section corresponding to FIG. The pins 22 of the package 20 are inserted into the mounting through holes 41 of the printed circuit board 40, and are fixed to the lower surface of the printed circuit board by solder 42 or the like. In this way, the semiconductor sensor can be mounted on a printed circuit board in exactly the same way as DIP mounting. Through hole 4 for mounting of printed circuit board 40
The input terminal of the semiconductor sensor chip can be connected to a power supply and a signal corresponding to the physical quantity detected by the semiconductor sensor can be output to the outside by a wiring (not shown) connected to 1. In detecting the physical quantity, the printed board is arranged so that the surface of the sensor chip of the semiconductor sensor mounted on the printed board is correctly oriented in the direction of the physical quantity to be detected.

By mounting the semiconductor sensor using such a package, the mounting area on the printed circuit board can be greatly reduced, and the direction of the physical quantity detected by the semiconductor sensor chip, ie, the semiconductor sensor chip The semiconductor sensor can be reliably fixed so that the direction perpendicular to the surface of the semiconductor sensor is parallel to the surface of the printed circuit board and coincides with the arrangement direction of the plurality of mounting through holes.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor sensor chip 10 sealed in a package 20 is formed on an integral silicon substrate as shown in FIG. 19, for example, and has an acceleration generated in a direction 700 perpendicular to the surface of the sensor chip. It may be an acceleration sensor chip for detecting, or an acceleration sensor chip described in JP-A-5-273229 or US Pat. No. 5,490,421 corresponding thereto. Hereinafter, embodiments of an acceleration sensor chip and an angular acceleration sensor chip which are most suitable to be applied to the semiconductor sensor of the present invention will be described.

FIGS. 3 and 4 show a first example of an acceleration sensor chip suitable as a semiconductor sensor of the present invention. FIG.
4A is a top view of the acceleration sensor chip, FIG. 3B is a cross-sectional view along the line aa, FIG. 4A is an enlarged top view of the detection unit, and FIG. It is sectional drawing which followed the bb line.

As shown in FIG. 3A, the substrate silicon 1
In a chip in which an SiO ₂ layer 102 serving as an electrical isolation and sacrificial layer is formed between the thin-film silicon 101 and the thin-film silicon 101, the thin-film silicon 101 has a detection unit 103 and a digital adjustment circuit 104 arranged at the center of the chip. , An analog amplifier circuit 105, an input / output terminal 106, and a digital adjustment terminal 107. Analog amplifier circuit 1
Reference numeral 05 denotes a circuit for amplifying the output of the detection unit 103, and a digital adjustment circuit 104 denotes a circuit for performing sensor sensitivity correction, temperature correction, and the like. The digital adjustment terminal 107 is a terminal for inputting data for that to the digital adjustment circuit 104.

As shown in FIG. 4A, the detecting unit 103
Is a weight 110, and projections (beams) 111a at four corners thereof.
₁ , 111a ₂ , 111b ₁ , 111b ₂ ,
The weight portion 110 has four corner protrusions (beam portions) 111a ₁ , 11
It is integrated with the surrounding support frame 112 via the _{1a 2, 111b 1, 111b 2} . This structure has a weight 11
0 is a pair of parallel beams on both sides, ie, a projection 11
_First beam and projection 11 including 1a ₁ and 111a ₂
This is a structure that is supported by the support frame 112 by a second beam portion including 1b ₁ and 111b ₂ . 108 through holes penetrating the thin film silicon 101, and using these through holes, the SiO ₂ layer 102 under the weight portion 110 and the beam portions 111 a ₁ , 111 a ₂ , 111 b ₁ , 111 b ₂ is removed by etching by wet etching. (Figure 3
(B) and FIG. 4 (b)). As a result, the weight portion 110 and the first and second beam portions can be displaced in a direction perpendicular to the surface. Weight 110 and beam 111a
₁ , 111a ₂ , 111b ₁ , and 111b _{2 have} the same thickness, for example, 5 μm, the weight 110 has a dimension of, for example, 850 μm × 600 μm, and the beam has a width of, for example, 30 μm.
m. Beam portions 111a ₁ , 111a ₂ , 111b ₁ ,
111b _{2 on} each of the support frame side and the weight side of both ends, that is, a total of eight semiconductor strain gauges 1
13a, 113b, 113c, 113d, 113e, 1
13f, 113g and 113h are formed by impurity diffusion. Reference numeral 114 denotes wiring connecting these strain gauges, and a Wheatstone bridge is formed by eight strain gauges. This Wheatstone bridge is connected to the constant voltage power supply Vcc and the ground GND.
, And the outputs V + and V− are guided to the amplifier circuit 105.

FIG. 5 is a block diagram of the acceleration detection circuit. Eight semiconductor strain gauges 113a, 113
b, 113c, 113d, 113e, 113f, 113
Outputs V + and V− of the Wheatstone bridge constituted by g and 113h are input to the amplifier circuit 105 and amplified. When acceleration acts in the direction of the arrow in FIG. 4B, the strain gauges 113b, 113c, 113 on the weight side
The compressive stress acts on f and 113g to reduce the resistance value, and the strain gauges 113a, 113d and 11 on the support frame side.
A tensile stress acts on 3e and 113h to increase the resistance value.
As a result, a sensor output corresponding to the magnitude of the acceleration is obtained from the Wheatstone bridge, and is amplified by the amplifier circuit 105. In addition, the digital adjustment circuit 104 corrects data Vg for sensitivity correction, data TCS for correcting temperature characteristics of sensitivity, and offset voltage Voff (sensor output in a state where no acceleration is applied) and offset voltage deviation. Is input to the amplifier circuit 105. The output of the amplifying circuit 105 is output through a high-pass filter 116 and a low-pass filter 117,
Is obtained. In this manner, the detection result corrected as necessary can be extracted as the bridge output voltage Vout. The high-pass filter 116 and the low-pass filter 117 may be external circuits, and the adjustment part of the frequency response region thereof may be incorporated in the digital adjustment circuit 104.

In this embodiment, the weight 110 is displaceably supported by the support frame 112 by two parallel beams 111a and 111b formed on both sides thereof. Measurement errors can be prevented. Further, in this example, since two strain gauges are arranged on one side of the bridge, the sensitivity of the sensor can be increased. In the present invention, since the Wheatstone bridge is constituted by the semiconductor strain gauge, the detection unit 103 and the substrate silicon 1
Even if a foreign matter having a size that does not hinder the movement of the weight portion enters between the positions of 00 and 00, the influence on the sensor characteristics is small unlike the case of the capacitive type.

Further, this embodiment has a function for confirming whether or not the performance of the acceleration sensor is normal, that is, a self-check function. This is because silicon having low specific resistance is used as the substrate silicon 100 and the electrode 115 provided on the back surface thereof is used.
A voltage Vself is externally applied to the substrate silicon 10
This is performed by generating a potential difference between 0 and the thin film silicon 101, displacing the sensor 103 by an electrostatic force caused by the potential difference, and detecting the output from the bridge at that time. The gap between the substrate silicon 100 and the thin film silicon 101 is determined by the thickness of the SiO ₂ layer therebetween.
In other words, the size of the gap can be easily controlled by controlling the thickness of the SiO ₂ layer when manufacturing the SOI wafer. Therefore, since the magnitude of the electrostatic force generated by the applied voltage can be easily and accurately calculated, self-diagnosis (self-check) can be performed by examining the relationship between the magnitude of the AC or DC voltage applied to the electrode 115 and the sensor output. It is possible. Of course, since the dimensions of the movable portion including the weight portion and the beam portion are determined at the time of design, the voltage range for causing the weight portion to displace in a range that does not make contact with the substrate silicon can be easily determined.

FIG. 6 shows a second example of an acceleration sensor chip suitable as a semiconductor sensor of the present invention. FIG. 6A is a top view, and FIG. 6B is an enlarged view of the detection unit.

Substrate silicon 100 and thin film silicon 101
The thin-film silicon 101 of the chip in which the SiO ₂ layer serving as the electrical isolation and sacrificial layer is formed between the sensing unit 200, the digital adjustment circuit 104, the analog amplification circuit 105, I / O terminal 106
And a digital adjustment terminal 107 are formed.
This example is different from the first example shown in FIGS. 3 to 5 in the structure of the detection unit and the arrangement of the semiconductor strain gauge associated therewith. The other points are the same as those in the first example, and the description is omitted.

The detecting unit 200 has two weights 201a,
01b, six connecting portions 211a ₁ connecting the two weight portions to the support frame portion 212 and connecting the two weight portions to each other.
_{211a 2, 211a 3, 211b 1} , 211b 2, 2
It consists 11b _3. A through-hole 108 is provided in the two weights and around the same as the weights of the first example, and the SiO ₂ below the two weights and the six connection parts is provided.
The layer has been etched away. Therefore, the two weight portions are connected to the connecting portions 211a ₁ , 211a ₃ , 211b ₁ , 21
Through 1b ₃ it is integrated with the surrounding support frame portion 212, and is displaceable in the direction perpendicular to the sheet plane. This structure, two pairs of beam portions two weight portions 201a and 201b are parallel, i.e. connecting portions 211a _1, 211a _2, 211a
₃ including the first beam portion and the connecting portions 211b ₁ , 211b ₂ ,
It is supported by the support frame 212 structure by a second beam portion including 211b _3. Connecting portion 211a of first beam portion
₁ , 211a ₃ and the connecting portion 211b of the second beam portion
Semiconductor strain gauges 213a, 213b, 213c, and 213d are respectively formed on ₂ and 211b ₃ by impurity diffusion. In order to increase the sensitivity, the thickness of the beam portion is preferably made smaller than the thickness of the weight portion (thickness of the thin film silicon). In this embodiment, the thickness of the beam portion is 2 μm with respect to the thickness of the weight portion of 5 μm. However,
To reduce the thickness of the beam, use a semiconductor strain gauge,
Before forming a circuit device or the like, pattern etching is performed to reduce the thickness of the beam portion.

FIG. 7 shows a Wheatstone bridge circuit in this embodiment. When the acceleration in the direction of the thickness of the weight portion in FIG. 6 toward the substrate silicon acts, a compressive stress acts on a portion of the beam portion where the semiconductor strain gauges 213b and 213d are formed. A tensile stress acts on the portion where 213c is formed. Therefore, the semiconductor strain gauge 213b
And the resistance of the semiconductor strain gauges 213a and 213c increases. By these operations, a voltage change according to the acceleration change is output from the Wheatstone bridge circuit.

FIG. 8 shows another example of the configuration of the detector having two weights. Unlike the detection unit shown in FIG.
01a and 201b are three sets of parallel beams, 211c ₁ and 2
11c ₂ , 211d ₁ and 211d ₂ , 211e ₁ and 21
It is coupled to the support frame portion by 1e _2. Weight part 20
1a and 201b are two parallel beam portions 2 as in the example of FIG.
They are connected by 11a and 211b. The beam portions 211d _1, 211a, 211b, and the semiconductor strain gauge 213a to 211d _2, 213b, 213
c and 213d are formed, and constitute a Wheatstone bridge. Since stress is generated on the surface of the beam due to acceleration, in order to enhance the stability of the wiring, a normal Al wiring structure (providing an Al wiring on a silicon via an insulating layer) as a wiring connecting the strain gauges is used. Instead, diffusion wiring may be used. In this case, the diffusion wiring is a sheet resistance, and its value is determined by the length and the width. In the example shown in FIG. 6, the portion where the strain gauge is formed in the beam portion connecting the weight portion and the support frame portion requires two wires on one beam, and therefore, the width of the wire is reduced. The sheet resistance becomes higher and the sheet resistance becomes higher, so that the sensitivity is reduced accordingly. On the other hand, in the example of FIG. 8, only one wire is provided for each beam, so that the wire width can be widened and a low-resistance wire can be formed. can do.

In this example, any combination can be used as long as the same gauge change can be obtained in order to constitute such a Wheatstone bridge, and the arrangement of the gauges and the combination of the gauges shown in FIGS. It is not limited.

FIG. 9 shows a third example of an acceleration sensor chip suitable as a semiconductor sensor according to the present invention. FIG. 9 (a)
9B is a top view, FIG. 9B is a cross-sectional view along the line dd, and FIG. 9C is an enlarged view of the sensor unit in FIG. 9B.

As in the first example, the thin-film silicon 101 of the chip in which the SiO ₂ layer 102 serving as the electrical isolation and sacrificial layer is formed between the substrate silicon 100 and the thin-film silicon 101 has a detecting unit 300 , A digital adjustment circuit 104, an analog amplification circuit 105, an input / output terminal 106, and a digital adjustment terminal 107. SiO at the lower part of the detector 300 arranged at the center of the chip
_{The two} layers 102 are etched away as in the first and second embodiments. As described later, for the self-check, a voltage can be applied between the substrate silicon 100 and the detection unit 300 to displace the sensor unit.

FIG. 10 is an enlarged top view of the detecting section. The detecting unit 300 uses a thin film forming technique such as a vacuum deposition method or a sputtering method to form a thin film magnet NbFeB.
(302) in which a magnetic thin film 301 of SmCo type or SmCo type is formed on the surface of the thin film silicon 101, and an elastic beam 303 connecting the weight and the support frame 112.
Consists of The SiO ₂ layer below the detection unit 300 has been removed as described above, and the thin film silicon around the detection unit has also been removed, and the through hole 1 for etching the sacrificial layer has been removed.
08, the weight portion 302 having the magnetic thin film 301 on its surface is integrated with the support frame portion via the elastic beam 303. When an acceleration perpendicular to the paper surface acts on the weight portion 302, the elastic beam 303 is formed. Is bent, and the weight portion can be displaced.
On the support frame around the through hole 108, a detection coil 304 is formed by a thin film technique so as to surround the weight.

FIG. 11 is a diagram for explaining the operation principle of this embodiment. As shown in FIG. 11A, the acceleration G
Works, and the weight portion 302, and thus the magnetic thin film 301,
When displaced upward, a current I flows through the detection coil 304 according to Lenz's law according to a change in the acceleration of the magnetic thin film 301. On the other hand, as shown in FIG. 11B, when the magnetic thin film 301 is displaced downward, a current I flows in the detection coil 304 in a direction opposite to that of FIG. The induced current I generated in this way is input to an integration circuit or the like, acceleration is input to a two-stage integration circuit, and velocity is input to a three-stage integration circuit to detect displacement.

FIG. 12 shows another example of the configuration of the detection unit. The weight portion 302 having the magnetic thin film 301 formed on the surface is supported by a plurality of elastic beams 303a and 303b. In this case, the displacement of the weight portion 302, and thus of the magnetic thin film 301, is a displacement in the direction perpendicular to the paper surface.

FIG. 13 shows a fourth example of an acceleration sensor chip suitable as a semiconductor sensor of the present invention. In this example, the detection units of the third example described above are connected in series. In the case of amplifying the signal of one detection unit, a sensor using a normal semiconductor strain gauge, a capacitance type sensor, etc.
Generally, the signal is amplified by an amplifier circuit. However, in the case of the acceleration sensor according to the present embodiment, it is possible to amplify the detection signal by the number of connected detection units by connecting a plurality of detection units in series due to the principle characteristic thereof. 13A is a low-acceleration detecting unit 401 in which a large number of detecting units 300 are connected, and FIG. 13B is a medium-acceleration detecting unit 402 in which a medium number of detecting units 300 are connected.
(C) shows a high-acceleration detecting unit 403 including one detecting unit 300. Furthermore, if a plurality of detection units having different detection ranges are formed on one chip, and the outputs of the plurality of detection units are switched and input to the amplifier, one acceleration sensor chip can be used. It can be used to detect a wide range of acceleration.

FIGS. 14 and 15 show examples of the circuit configuration of the fourth example. In both figures, only the detection coils 304 of the two sensor units are shown for simplicity. The amplifying circuit 1 having the function of adjusting the digital adjustment circuit 104 by converting the induced current induced in the detection coil 304 of the sensor unit 300 into a voltage output by the voltage conversion resistor 411.
05, a high-pass filter circuit 116, a low-pass filter circuit 117, and the like. FIG.
FIG. 15 shows an example in which the digital adjustment circuit 104 and the amplification circuit 105 are provided on a chip other than the chip on which the detection unit is formed. FIG. 15 shows an example in which these are formed on the same chip as the detection unit.

In this example, as shown in FIG. 9C, the detection unit is moved by an electrostatic force generated when a voltage is applied between the substrate silicon 100 and the detection unit 300, and the detection unit at this time is moved. The self-check can be performed by amplifying and outputting the induced current induced in the detection coil by the amplifier circuit 105 in accordance with the movement of. In this embodiment, the self-check can be performed using the changeover switches 412 and 413 for switching between the normal acceleration detection and the self-check. That is, switching is performed such that current flows to the detection terminals 414 and 415 during normal acceleration detection, and current flows to the self-check terminal 416 during self-check. At the time of self-check, the detection coil 3
A self-check can be performed by applying a pulse output to the sensor unit 04 and applying an impulse-like electromagnetic force to the sensor unit 300 to move the weight unit 302 and processing and confirming the response at that time by a circuit subsequent to the amplifier circuit. is there. According to these methods, the self-check function can be realized with a simple configuration. Further, in addition to the above method, a permanent magnet or an electromagnet is arranged near the detection unit 300, a magnetic field is externally applied to the sensor unit, and an induced current generated in the detection coil 304 when the detection unit 300 is moved by the magnetic field. It is also possible to perform self-check upon detection.

It goes without saying that these self-check functions can be added to the acceleration sensor of the third example.

FIG. 16 shows a fifth example of a sensor chip suitable as a semiconductor sensor of the present invention. In this example, the angular acceleration is detected by combining two of the third example shown in FIG. 8 or the fourth example shown in FIG.
In the present embodiment, three detection units 300L and 300R are arranged symmetrically on the left and right sides of the detection axis X, respectively. Detection axis X
When the angular acceleration changes around, for example, the weight portion is displaced upward in the left detection portion, and the weight portion is displaced downward in the right detection portion. As shown in FIG. 17, these detection units detect a change in angular acceleration around the detection axis X,
They are connected so as to form a closed loop in which currents in the same direction flow through the detection coils 304L and 304R of the left and right detector arrays. Then, as in the fourth example, the current is converted into a voltage by the voltage conversion resistor 411, integrated and amplified, and used as an angular acceleration detection sensor for detecting the angular acceleration generated around the detection axis X. it can.

The present invention is applicable not only to the acceleration sensor and the angular acceleration sensor described above, but also to a semiconductor sensor for detecting a physical quantity whose directionality is important. Further, in the semiconductor sensor shown in FIGS. 1 and 2, an example has been described in which the main surface for mounting the semiconductor sensor chip is substantially perpendicular to the surface of the printed circuit board on which the package is mounted. However, the angle of the main surface for mounting the semiconductor sensor chip with respect to the surface of the printed circuit board on which the package is mounted depends on the direction of the physical quantity to be detected and the position where the printed circuit board constituting the sensor assembly is mounted. Can be selected.

FIG. 18 shows an example in which the direction 30 of the physical quantity acting perpendicular to the surface of the semiconductor sensor chip is 45 degrees with respect to the printed circuit board 40. Since the reference numerals are all the same as in FIG. 2, the description is omitted. In this case, the main surface of the semiconductor sensor package on which the semiconductor sensor chip 10 is mounted is oriented at 45 degrees with respect to the printed circuit board 40. As described above, the principal surface of the package on which the semiconductor sensor chip for detecting the physical quantity acting in the direction perpendicular to the surface of the semiconductor sensor chip is positioned in the direction of the physical quantity to be detected and the direction in which the printed circuit board is actually mounted. It is selected in consideration of.

[0048]

As described above, according to the present invention,
The following effects can be obtained.

1) The mounting area can be reduced, and the entire detection system including the sensor can be reduced in size.

2) As in the case of an ordinary IC, since it can be soldered and mounted on a printed circuit board using pins, the manufacturing process can be easily automated and the manufacturing cost can be reduced.

3) Since the pins can be inserted into the printed circuit board and mounted, the direction of the physical quantity to be detected and the direction of the sensor chip can be reliably limited to one direction, and the reliability of the detection signal can be reduced. Can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of a semiconductor sensor according to the present invention.

FIG. 2 is a schematic sectional view illustrating a method for mounting a semiconductor sensor on a printed circuit board according to the present invention.

FIG. 3 is a diagram showing a first example of an acceleration sensor chip suitable for a semiconductor sensor according to the present invention.

FIG. 4 is an enlarged view of a detection unit of the acceleration sensor chip of FIG.

FIG. 5 is a block diagram of an acceleration detection circuit in the first example.

FIG. 6 is a diagram showing a second example of an acceleration sensor chip suitable for a semiconductor sensor according to the present invention.

FIG. 7 is a diagram illustrating a Wheatstone bridge circuit in a second example.

FIG. 8 is a diagram illustrating another configuration example of the detection unit.

FIG. 9 is a diagram showing a third example of an acceleration sensor chip suitable for a semiconductor sensor according to the present invention.

FIG. 10 is an enlarged view of a detection unit of the acceleration sensor chip of FIG.

FIG. 11 is a diagram illustrating the operation principle of the third example.

FIG. 12 is a diagram illustrating another configuration example of the detection unit in the third example.

FIG. 13 is a diagram showing a fourth example of an acceleration sensor chip suitable for a semiconductor sensor according to the present invention.

FIG. 14 is a diagram illustrating an example of a circuit configuration in a fourth example.

FIG. 15 is a diagram showing another example of the circuit configuration in the fourth example.

FIG. 16 is a diagram showing an angular acceleration sensor chip as a fifth example of a sensor chip suitable for a semiconductor sensor according to the present invention.

FIG. 17 is a diagram illustrating an example of a circuit configuration according to a fifth example.

FIG. 18 is a schematic view illustrating another example of the semiconductor sensor according to the present invention.

FIG. 19 is a schematic view showing an example of a conventional semiconductor sensor.

FIG. 20 is a diagram illustrating an example of a conventional acceleration sensor chip.

[Explanation of symbols]

Reference Signs List 10 semiconductor sensor chip 20 package 20A sensor fixing surface 21 lid 22 pin 23 wire bond pad 24 thin metal wire 25 wiring 30 acceleration direction 40 printed circuit board 41 mounting through hole 42 solder 100 substrate silicon 101 thin film silicon 102 insulating layer (sacrifice layer) 103 the sensor unit 104 a digital adjustment circuit 105 analog amplifier circuit 106 input terminal 107 digital adjustment terminal 108 through hole 110 weight portions _{111a 1, 111a 2, 111b 1} , 111b 2 beam portion 112 supporting frame portion 113a~113h semiconductor strain gage 114 the wiring 115 electrode 116 pass filter 117 low-pass filter 118 resist 119 slit 120 jig 121 completed chip 200 sensor unit 201a, 201b weight portion 211a _{1 211a 2, 211a 3, 211b 1} , 2
11b ₂ , 211b ₃ Beam section 212 Support frame section 213a to 213d Semiconductor strain gauge 300 Sensor section 301 Magnetic thin film 302 Weight section 303, 303a, 303b Elastic beam 304 Detection coil 401 Low acceleration sensor 402 Medium acceleration sensor 403 High acceleration Sensor 411 Voltage conversion resistor 412, 413 Changeover switch 414, 415 Detection terminal 416 Self-check terminal 500 Semiconductor sensor chip 510 Beam 520 Weight 530 Support frame 540A, 540B, 540C, 540D Semiconductor strain gauge 550 Wiring 600 Package 700 Acceleration direction 800 Printed circuit board 900 High rigidity board X Rotation axis

Claims (11)

[Claims] 1. A semiconductor sensor chip for detecting a physical quantity acting in a direction perpendicular to a surface of a chip, and a package for accommodating the semiconductor sensor chip, wherein a main surface on which the semiconductor sensor chip is mounted has a main surface. It is configured at a predetermined angle with respect to the surface of the printed board on which the package is mounted, and the main surface is provided with a plurality of terminals for connecting to the input / output terminals of the semiconductor sensor chip along two opposing sides thereof. A plurality of pins are provided on a bottom surface perpendicular to the main surface along two sides parallel to the two sides of the main surface so as to be inserted into mounting holes formed in the printed circuit board. A semiconductor sensor package in which the plurality of terminals and the plurality of pins are electrically connected; and an input / output terminal of a semiconductor sensor chip mounted on the main surface and the package. Semiconductor sensor wherein a plurality of terminals over di are electrically connected. 2. The semiconductor according to claim 1, wherein a main surface on which the semiconductor sensor chip is mounted is formed substantially perpendicular to a surface of a printed circuit board on which the package is mounted. Sensor. 3. The semiconductor sensor chip according to claim 1, wherein the semiconductor sensor chip is a semiconductor acceleration sensor chip.
A semiconductor sensor according to claim 1. 4. The sensor structure according to claim 1, wherein the semiconductor acceleration sensor chip includes a support frame, a sensor structure including at least one displaceable weight and a beam connecting the weight to the support frame. An acceleration sensor chip formed on thin film silicon formed via an insulating layer,
The insulating layer between the sensor structure and the substrate silicon has been removed, the beam portion comprises a plurality of sets of beams parallel to each other, and the weight portion comprises the support frame portion by the plurality of sets of parallel beams. 4. The semiconductor sensor according to claim 3, wherein the acceleration sensor chip is connected to a plurality of parallel beams and has at least two semiconductor strain gauges formed on surfaces of the plurality of parallel beams. 5. 5. The sensor structure according to claim 1, wherein the semiconductor acceleration sensor chip includes a support frame, a displaceable weight having a magnetic thin film formed on a surface thereof, and a beam connecting the weight to the support frame. The insulating layer formed between the sensor structure and the substrate silicon is formed on the thin film silicon formed on the substrate silicon via an insulating layer, and the weight is placed on the support frame around the weight. The semiconductor sensor according to claim 3, wherein the semiconductor sensor is an acceleration sensor chip in which a coil is formed around a portion. 6. The sensor according to claim 1, wherein the semiconductor acceleration sensor chip includes a support frame, a displaceable weight having a magnetic thin film formed on a surface thereof, and a beam connecting the weight to the support frame. A structure is formed on the thin film silicon formed on the substrate silicon via an insulating layer, the insulating layer between the plurality of sensor structures and the substrate silicon is removed, and the periphery of each of the weights is removed. 4. The semiconductor sensor according to claim 3, wherein each of the coils is formed on the supporting frame portion so as to surround a weight portion, and the plurality of coils are connected in series. 7. The semiconductor sensor according to claim 1, wherein the semiconductor sensor chip is a semiconductor angular acceleration sensor chip. 8. The semiconductor angular acceleration sensor chip includes a first support frame, a displaceable first weight having a magnetic thin film formed on a surface thereof, and the first weight, respectively. A plurality of first beams each including a first beam portion connected to the support frame portion;
Wherein the sensor structure is formed on thin-film silicon formed on a substrate silicon via an insulating layer, the insulating layer between the plurality of first sensor structures and the substrate silicon is removed, A first detection coil is formed around the first weight on the first support frame around each of the first weights, and the plurality of first detection coils are connected in series. A first sensor group, a second support frame, a displaceable second weight having a magnetic thin film formed on a surface thereof, and connecting the second weight to the second support frame; A plurality of second sensor structures each including a second beam portion are formed on the thin-film silicon formed on the substrate silicon via an insulating layer, and a plurality of second sensor structures and the substrate silicon are formed. The insulating layer between the two layers has been removed. A second detection coil is formed on a second support frame around each of the first and second portions surrounding the second weight portion, and the plurality of second detection coils are connected in series; The sensor group is formed on the same semiconductor chip, the number of sensor structures of the first sensor group and the number of sensor structures of the second sensor group are equal, and the first sensor group and the second sensor group have a detection axis. The currents flowing through the plurality of first and second detection coils of the first and second sensor groups are in the same direction when the angular acceleration around the detection axis is arranged symmetrically as the axis of symmetry. As described above, the first and second detection coils of the first and second sensor groups form a closed loop, and amplifies signals from the plurality of first and second detection coils, and the plurality of detection coils. Outputs angular velocity signal by integrating output from Claim 7, characterized in that an angular acceleration sensor chip with means that
A semiconductor sensor according to claim 1. 9. A package accommodating a semiconductor sensor chip, wherein a main surface for mounting the semiconductor sensor chip is formed at a predetermined angle with respect to a surface of a printed circuit board on which the package is mounted, and wherein the main surface is provided. Are provided with a plurality of terminals for connection to input / output terminals of the semiconductor sensor chip along two opposing sides thereof, and a bottom surface perpendicular to the main surface is provided with a plurality of terminals parallel to the two sides of the main surface. A plurality of pins are respectively provided along the sides so as to be inserted into mounting holes formed in the printed board, and the plurality of terminals and the plurality of pins provided along the parallel sides are provided. A semiconductor sensor package electrically connected along two side surfaces sandwiching the main surface. 10. The semiconductor according to claim 9, wherein a main surface for mounting the semiconductor sensor chip is substantially perpendicular to a surface of a printed circuit board on which the package is mounted. Package for sensors. 11. The semiconductor sensor package according to claim 9, wherein a wiring connecting the plurality of terminals and the plurality of pins is embedded in the package.