JPH081467Y2 - Semiconductor pressure sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a pressure measuring device in which a sensor chip and a substrate and a substrate and a supporting portion are anodically bonded, and the anodic bonding is easy and the yield is high. is there.

<Prior Art> FIG. 11 is a structural explanatory view of a conventional example which has been generally used, and is shown in, for example, Japanese Utility Model Application Laid-Open No. 64-27635.

In the figure, 1 is a sensor chip made of a silicon semiconductor, and 11 is a recess for forming a diaphragm 12 in the sensor chip 1.

Reference numeral 13 is a semiconductor piezoresistive gauge provided on the diaphragm 12.

Reference numeral 2 is a substrate made of Pyrex glass, one surface of which is bonded to the sensor chip 1 to form the recess 11 and the reference chamber 14.

Reference numeral 3 denotes a cylindrical support portion which is attached to the other surface side of the semiconductor substrate 2 and is made of metal.

Reference numeral 4 denotes a metal housing to which the other end of the support portion 3 is attached.

In the above structure, the reference pressure Ps is introduced into the reference chamber 13, and the measurement pressure Pm is applied to the outer surface of the diaphragm 12. Since the resistance change corresponding to the measurement pressure Pm is obtained from the semiconductor piezoresistance gauge 13, the measurement pressure Pm can be measured.

<Problems to be Solved by the Invention> However, in such a device, the substrate 2 is also anodically bonded to the sensor chip 1 and the support portion 3.

As an anodic bonding method, as shown in FIG. 12, (1) the electrode A is brought into contact with the central portion of the side surface of the substrate 2 of Pyrex glass, and the sensor chip 1 is connected to the positive electrode and the electrode A.
To the negative pole and perform anodic bonding.

(2) Next, anodic bonding is performed with the supporting portion 3 as a positive electrode and the electrode A as a negative electrode.

However, with this method, (1) the minus electrode A needs to be brought into contact with the side surface, so that the joining jig may be large in the lateral direction and may be complicated.

(2) Due to the lateral contact force of the negative electrode A, the joining force in the axial direction of the support portion 3 is weakened, the contact between the surfaces to be joined becomes poor, and this may cause poor joining.

(3) A large number of chips cannot be joined on a wafer-by-wafer basis.

 The present invention solves this problem.

An object of the present invention is to provide a pressure measuring device which is capable of anodic bonding between a sensor chip and a substrate, and a substrate and a supporting portion, and which is easy to perform anodic bonding and has a high yield.

<Means for Solving the Problem> In order to achieve this object, the present invention provides a sensor chip made of a semiconductor, a recess for forming a diaphragm on the sensor chip, and a semiconductor piezoresistive gauge provided on the diaphragm. A substrate made of a glass material having movable ions, one surface of which is anodically bonded to the sensor chip and forming a recess and a reference chamber; and a cylindrical support portion of which one surface is anodically bonded to the other surface of the substrate and made of metal. A stepped portion that is provided on the outer peripheral portion of the substrate and has a negative electrode attached in the axial direction of the supporting member during anodic bonding between the sensor chip and the substrate or during anodic bonding between the substrate and the supporting portion,
The pressure measuring device comprises a metal housing to which the other end of the support portion is attached.

<Operation> In the above configuration, the reference pressure is introduced into the reference chamber, and the measurement pressure is applied to the outer surface of the diaphragm. The measurement pressure can be measured by obtaining the resistance change corresponding to the measurement pressure from the semiconductor piezoresistive gauge.

Thus, the sensor chip, the substrate, and the supporting portion are set in the axial direction of the supporting portion, and the positive electrode for anodic bonding,
The negative electrode can also be set from the axial direction.

 Hereinafter, detailed description will be given based on examples.

<Embodiment> FIG. 1 is an explanatory view of a main part configuration of an embodiment of the present invention.

 In the figure, the same symbols as in FIG. 11 represent the same functions.

 Only parts different from FIG. 11 will be described below.

Reference numeral 21 is a concave portion in which one surface side is anodically bonded 22 to the sensor chip 1.
11 is a substrate made of a glass material having mobile ions that configure the reference chamber 11 and the reference chamber 14.

 In this case, Pyrex glass is used.

Reference numeral 23 denotes a cylindrical support portion made of metal, one surface of which is anodically bonded 24 to the other surface side of the substrate 21.

25 is provided on the outer peripheral portion of the substrate 21 and is used for anodic bonding 22 between the sensor chip 1 and the substrate 21, or the substrate 21 and the supporting portion.
A negative electrode is a step portion attached in the axial direction of the support portion 23 at the time of anodic bonding 24 with the support portion 23.

In the above configuration, the reference pressure is introduced into the reference chamber 14,
A measurement pressure Pm is applied to the outer surface of the diaphragm 12. The resistance change corresponding to the measurement pressure Pm is semiconductor piezo resistance gauge 13
As a result, the measurement pressure Pm can be measured.

Thus, the sensor chip 1, the substrate 21, and the supporting portion 23 are set in the axial direction of the supporting portion 23, and the negative electrode A for anodic bonding can also be set in the axial direction.

As a result, (1) the minus electrode A is supported by the support portion 23 with respect to the substrate 21.
Since a contact force can be applied in the axial direction of, the contact force from the side of the substrate of the negative electrode A weakens the bonding pressure in the axial direction of the supporting portion 3 as in the conventional example, and the contact between the surfaces to be bonded is There is no possibility of becoming defective and causing defective bonding, and the bonding yield can be improved.

(2) Since it is not necessary to contact the negative electrode A from the side surface of the substrate 21 and a contact force can be applied from the axial direction of the support portion 23, the joining jig can be made compact and the manufacturing cost can be reduced. You can do it.

(3) A large number of sensor chips 1 can be joined on a wafer basis.

More specifically, as shown in FIG. 2, this device is manufactured as follows.

(1) As shown in FIG. 2A, a step 25 is formed on the substrate 21 by dicing or the like.

(2) As shown in FIG. 2 (B), with the surface of the step portion 25 facing the sensor chip 1, the sensor chip 1, the substrate 21 and the supporting portion are provided.
Set 23 and.

(3) As shown in FIG. 2 (C), the minus electrode A is brought into contact with the step portion 25, and the plus electrode B (also serving as a weight for load) is brought into contact with the sensor chip 1. A voltage (about 500 B, about 2 minutes) is applied at a high temperature (about 400 ° C.) to perform anodic bonding 22.

(4) As shown in FIG. 2D, the minus electrode A is left as it is, the plus electrode C is brought into contact with the supporting portion 23, a voltage is applied, and the anodic bonding between the substrate 21 and the supporting portion 23 is performed.

The reason why the step portion 25 is formed on the substrate 21 is that, as shown in FIG. 3, when the minus electrode A is brought into contact with the outside of the substrate 21 and a voltage is applied in the state where the substrate 21 has no step, it is shown in FIG. As shown, the current lines end up concentrating on the joint surface of the X portion, and as a result, the joint surface of the Y portion far from the negative electrode A becomes defective. The non-uniformity of bonding on the bonding surface also causes drift of the device due to aging.

Therefore, as shown in FIG. 5, when the step portion 25 is formed and the minus electrode A is brought into contact with the outside of the step portion 25, the step portion 25 is formed.
The difference in the distance between the bottom surface of the sensor chip 1 and the substrate 21 between the sensor chip 1 and the substrate 21 at the X and Y portions is improved, and good bonding becomes possible.

FIG. 6 is an explanatory view of the essential parts of another embodiment of the present invention.

In the present embodiment, the step portion 31 is provided so as to face the support portion 23 side and contacts from the support portion 23 side.

FIG. 7 is an explanatory view of a main part configuration of another embodiment of the present invention.

In this embodiment, the step portion 41 is provided on the entire outer circumference of the substrate 21.

FIG. 8 is an explanatory view of a main part configuration of another embodiment of the present invention.

In this embodiment, the step portion 51 is provided only on a part of the substrate 21.

FIG. 9 is an explanatory view of the essential structure of another embodiment of the present invention.

In this embodiment, each substrate 21 is provided with each silicon wafer 61 before being diced into each sensor chip 1.
It is designed to be anodically bonded to. The step is the sixth
This utilizes the step portion 31 of the illustrated embodiment.

FIG. 10 is an explanatory view of the essential structure of another embodiment of the present invention.

In this embodiment, the groove 71 is provided in the vicinity of the outer peripheral portion of the substrate 21 and the step portion is provided in substantially the same manner.

The negative electrode A is attached to the substrate 21 outside the groove 71.

<Effects of the Invention> As described above, the present invention provides a sensor chip made of a semiconductor, a recess for forming a diaphragm on the sensor chip, a semiconductor piezoresistive gauge provided on the diaphragm, and one surface side of the sensor chip. A substrate made of a glass material having movable ions that are anodic-bonded to form the recess and the reference chamber, a cylindrical support part made of metal anodically bonded to the other side of the substrate, and a peripheral part of the substrate. A stepped portion provided with a negative electrode in the axial direction of the support member at the time of anodic bonding between the sensor chip and the substrate or at the time of anodic bonding between the substrate and the supporting portion, and the other end of the supporting portion are mounted. And a housing made of metal to be used.

As a result, (1) Since the minus electrode can apply a contact force to the substrate in the axial direction of the supporting portion, the contact force of the minus electrode from the side of the substrate causes the supporting portion of the supporting portion to move like the conventional example. The bonding pressure in the axial direction becomes weak, the contact between the surfaces to be bonded becomes poor, and there is no possibility of causing defective bonding, and the bonding yield can be improved.

(2) Since it is not necessary to contact the negative electrode from the side surface of the substrate and a contact force can be applied in the axial direction of the supporting portion, the joining jig can be made compact and the manufacturing cost can be reduced. I can.

(3) A large number of sensor chips can be joined on a wafer basis.

Therefore, according to the present invention, it is possible to realize a pressure measuring device in which the sensor chip and the substrate and the substrate and the supporting portion are anodic-bonded, and the anodic-bonding is easy and the yield is high.

[Brief description of drawings]

FIG. 1 is an explanatory view of the essential parts of an embodiment of the present invention, FIG. 2 is a manufacturing explanatory view of FIG. 1, FIGS. 3 to 5 are operation explanatory views of FIG. 1, and FIG. 6 to FIG. FIG. 10 is a structural explanatory view of the essential parts of another embodiment of the present invention, FIG. 11 is a structural explanatory view of a conventional example which is generally used conventionally, and FIG. 12 is an operational explanatory view of FIG. 1 ... Sensor chip, 11 ... Recess, 12 ... Diaphragm, 13 ... Semiconductor piezoresistive gauge, 14 ... Reference chamber, 21
…… Substrate, 22 …… Anodic bonding, 23 …… Supporting part, 24 …… Anodic bonding, 25,31,41,51 …… Step, 61 …… Silicon wafer, 71 …… Groove, A …… Negative electrode , B ... Positive electrode.

Claims (1)

[Scope of utility model registration request] 1. A sensor chip made of a semiconductor, a recess for forming a diaphragm on the sensor chip, a semiconductor piezoresistive gauge provided on the diaphragm, and one side of the sensor chip being anodically bonded to the recess and a reference chamber. A substrate made of a glass material having movable ions, a cylindrical support portion made of metal, one surface of which is anodically bonded to the other surface side of the substrate, and the sensor chip provided on the outer peripheral portion of the substrate and the substrate. A step portion to which a negative electrode is attached in the axial direction of the support member during anodic bonding or anodic bonding between the substrate and the support portion; and a housing made of metal to which the other end of the support portion is attached. Pressure measuring device.