JPH09178588A - Semiconductor pressure sensor and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost by sharing the bonding method and the components between a chip and the body part. SOLUTION: A chip 4 (pressure-sensitive chip 2, glass base 3) and a pressure introduction pipe 5 are previously bonded at a first bonding part 7 to constitute a bonded body 6 of pipe and pressure introduction pipe. The bonded body 6 is employed as a basic component and bonded to the body part 10 provided with the signal take-out part 9 of pressure-sensitive chip 2 at a second bonding part 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor pressure sensor for converting pressure into an electric signal and a method for manufacturing the semiconductor pressure sensor.

[0002]

2. Description of the Related Art As a conventional semiconductor pressure sensor 1, for example, as shown in FIG. 17, a pressure sensitive chip 2 mainly made of silicon single crystal is joined to a silicon plate 80 through a glass pedestal 3 and a main body portion 10 is provided. The pressure-introducing pipe 5 integrated with the ′ ′ is joined by soldering, and the signal output pin 9a sealed in the hermetically sealed portion of the main body 10 ′ is connected to the pressure-sensitive chip 2 via the wire bonding 81. It is known that the housing 90 is hermetically housed (see, for example, Japanese Patent Laid-Open No. 2-69630).

As a conventional method of manufacturing a semiconductor pressure sensor, the method shown in FIGS. 18 and 19 is known. The semiconductor pressure sensor 1'shown in FIG. 18A is manufactured based on the process shown in FIG. First, a chip 4 is obtained by dicing a bonded body (wafer bonded body) in which a glass wafer that has been punched and a silicon wafer having a diaphragm are bonded in advance. On the other hand, the stem pedestal 18 and the signal output pin 9a are processed to obtain the stem pedestal 1
The signal output pin 9a and the pressure introducing pipe 5 are sealed and joined to the rod 8 to obtain a stem joined body. Then, after joining the stem joined body and the chip 4, the chip 4 and the signal output pin 9a are connected by wire bonding (not shown), and finally mounted on the housing.

On the other hand, the semiconductor pressure sensor 1 "shown in FIG. 18 (b) is similarly manufactured according to the process shown in FIG.

[0005]

The semiconductor pressure sensor, depending on the pressure to be measured and its environment, is used in the chip 6
Stem has a substantially same shape,
The main body portion 10 'including a wide variety of materials and shapes from plastic to metal. For this reason, a plurality of types of jigs for the main body portion are required to bond the chip 4 to the main body portion 10 '.
A joining method (adhesive, soldering, etc.) according to 0'is required. Moreover, in the conventional examples, the pressure introducing pipe 5 and the signal output pin 9a are integrated with the main body portion 10 ', and since the chip 4 is joined to the main body portion 10', the common component is the chip 4 However, it is difficult to standardize the joining method and the parts of the main body portion 10 ', and this makes it impossible to reduce the manufacturing cost. Further, in the conventional example, in joining the chip 4 and the metal (pressure introducing pipe 5), there is a restriction due to the main body portion 10 '(for example, the main body portion 1).
If there is a wire bonding portion at 0 ', the bonding temperature cannot be raised, and there is a problem that the discoloration of the appearance of the main body 10' causes a problem that bonding cannot be performed in an oxidizing atmosphere.

The present invention has been made in view of the above points, and it is possible to achieve a common bonding method for a chip and a main body and common parts of the main body, and to reduce the cost. It is an object of the present invention to provide a pressure sensor and a method for manufacturing the same, and further, it is possible to relieve thermal stress of the main body and prevent cracks from occurring, and to position the tip-pressure introduction pipe joined body in the vertical and rotational directions with respect to the main body. It is an object of the present invention to provide a semiconductor pressure sensor and a method for manufacturing the same, which can easily perform the above-mentioned process and which is not restricted by the bonding temperature and the like of the first bonding portion when the second bonding portion is bonded.

[0007]

In order to solve the above-mentioned problems, in a semiconductor pressure sensor according to the present invention, a pressure-sensitive chip 2 for measuring the pressure of a fluid introduced from the outside has a glass pedestal 3.
The chip 4 and the pressure-introducing pipe 5 for introducing pressure to the pressure-sensitive chip 2 are joined together to form the first joint 7
Is joined in advance to form the tip-pressure introducing pipe joined body 6, and the tip-pressure introducing pipe joined body 6 is connected to the main body portion 10 having the signal output portion 9 of the pressure-sensitive tip 2 at the second joining portion. It is characterized by being joined at 8. With this configuration, the tip 4 and the pressure introducing pipe 5
The chip-pressure introducing pipe joined body 6 in which the and are previously joined can be joined to the main body portion 10 as a basic component, and the joining method of the tip 4 and the main body portion 10 is made common and the parts of the main body portion 10 are made common. It will be easy.

Here, when the second joint portion 8 is joined by local heating, it is preferable to provide a notch 30 for preventing heat shrinkage on the surface of the main body portion 10. In this case, the notch 30 is provided by insertion. Even with a semiconductor pressure sensor of the type, the thermal stress of the main body portion 10 can be relaxed by utilizing the notch 30, and a thermal adverse effect on the sealing portion of the signal output portion 9 can be prevented.

An insertion tube portion 15 into which the pipe portion 6a of the tip-pressure introducing pipe assembly 6 is inserted into the body portion 10.
And a screw-in portion 1 for installation on the outer surface side of the insertion tube portion 15.
6 is provided, a small diameter portion 50 for tightening the pipe portion 6a at the time of insertion before joining is provided on the inner surface side of the insertion tubular portion 15, and a gap between the small diameter portion 50 and the pipe portion 6a is provided at the second joining portion 8 And in this case the second joint 8
When joining by welding, the gap between the welded parts is reduced, and welding defects can be eliminated.

It is preferable that the pipe portion 6a of the tip-pressure introducing pipe joined body 6 is provided with a positioning portion 17 which is positioned in the main body portion 10 before joining. In this case, the positioning portion 17 is used to make use of the main body portion 10. It becomes easy to position the tip-pressure introduction pipe assembly 6 with respect to the vertical direction and the rotation direction. Further, in the method for manufacturing a semiconductor pressure sensor according to the present invention, the pressure sensitive chip 2 for measuring the pressure of the fluid introduced from the outside and the glass pedestal 3 are joined to obtain the chip 4,
The tip 4 and the pressure-introducing pipe 5 for introducing pressure into the pressure-sensitive tip 2 are pre-joined at the first joining portion 7 to obtain a tip-pressure introducing pipe joined body 6, and then the pressure-sensitive pipe is joined. It is characterized in that the main body portion of the chip 2 having the signal output portion 9 and the above-mentioned chip-pressure introducing pipe joined body 6 are joined at the second joining portion 8, and therefore, the tip-pressure introducing member which is a basic component. The pipe-joining body 6 for a pipe is formed in advance, and then the pipe-joining body 6 for introducing the tip-pressure and the body portion 1 are formed.
The second joint portion 8 with 0 can be joined without being restricted by the first joint portion 7 such as the joining temperature.

Here, the second joint 8 between the tip-pressure introducing pipe joint body 6 and the main body portion 10 is energized from the side opposite to the pressure-sensitive tip 2 of the tip-pressure introducing pipe joint body 6. It is preferable to perform heat bonding by irradiating a beam, and in this case, the second bonding portion 8 between the tip-pressure introducing pipe bonding body 6 and the main body portion 10 which are basic components.
By irradiating an energy beam from the side A opposite to the pressure-sensitive tip 2 of the tip-pressure introduction pipe joined body 6, the joining of the tip-pressure introduction pipe joined body 6 is not restricted by the joining temperature of the first joining portion 7 and the like. It can be performed by heating.

Further, it is preferable to heat-bond the first joint portion 7 by using a metal brazing material or a bonding material having a linear expansion coefficient close to that of the low melting point glass. In the case of the metal brazing material, the corrosion resistance is excellent. In the case of low melting point glass, the thermal stress is small. It is preferable that the first bonding portion 7 is bonded by anodic bonding. In this case, no bonding material is required, and the cost can be further reduced.

An insertion cylinder portion 15 into which the pipe portion 6a of the tip-pressure introducing pipe assembly 6 is inserted is formed in the main body portion 10 in advance, and a screwing portion for installation is provided on the outer surface side of the insertion cylinder portion 15. 16 is formed, and it is preferable to heat bond the gap between the insertion cylinder portion 15 and the pipe portion 6a by irradiating an energy beam from the side opposite to the pressure sensitive tip 2, and in this case, it is installed by screwing. Even if it is a semiconductor pressure sensor of a type, the second bonding portion 8 is not restricted by the bonding temperature and the like of the first bonding portion 7.
It becomes possible to perform the joining by local heating.

At the same time that the main body portion 10 is formed by resin molding, it is preferable to incorporate the signal output portion 9 inside the resin. In this case, the main body portion 10 and the signal output portion 9 can be easily integrated.

[0015]

Embodiments of the present invention will be described below. The semiconductor pressure sensor is a semiconductor pressure sensor 1A of the type installed by insertion (Fig. 1 (b), Fig. 4).
(A)) and a semiconductor pressure sensor 1B of a type installed by screwing (FIG. 4 (b)), and the semiconductor pressure sensor of the present embodiment is applicable to any type, In the insertion type semiconductor pressure sensor 1A shown in FIG. 4A, the main body 10 is made of, for example, resin, and the signal output pin 9a constituting the signal output portion 9 is integrally incorporated in the resin. On the other hand, in the screw-in type semiconductor pressure sensor 1B of FIG. 4B, the main body 10 is made of, for example, metal, and the main body 10 is provided with the substrate support 14 for supporting the substrate 13 and the main body 10. An insertion cylinder portion 15 is provided which protrudes to the lower part of 10 to insert the pipe portion 6 a of the tip-pressure introduction pipe joined body 6.
A threaded portion 16 for installation is provided on the outer surface side of the.

As shown in FIG. 1A, this semiconductor pressure sensor has a pressure sensitive chip 2 made of, for example, a silicon single crystal.
A tip 4 formed by joining a glass pedestal 3 and a pressure introducing pipe 5 for introducing pressure to the pressure-sensitive tip 2 are pre-joined at a first joining portion 7 to provide a tip-pressure introducing pipe. The joined body 6 is configured. And this chip-
Using the pressure-introducing pipe joined body 6 as a basic component, the body portion 10 of the pressure-sensitive chip 2 provided with the signal output portion 9 and the tip-pressure introducing pipe joined body 6 are joined together at the second joined portion 8. It has become. 11 in the figure is wire bonding,
Reference numeral 12 is a sealing material.

Here, as the glass pedestal 3, for example, Pyrex glass (trade name) having a linear expansion coefficient close to that of silicon.
As the pressure introducing pipe 5, a metal material such as Kovar or 42 alloy (trade name) having a linear expansion coefficient close to that of the glass pedestal 3 is used. Further, the chip 4 (the pressure-sensitive chip 2, the glass pedestal 3) and the pressure introducing pipe 5 are joined (first joining) by a joining material having an expansion coefficient close to that of the constituent material of the glass pedestal 3 or the pressure introducing pipe 5. ,
For example, low melting glass or a metal brazing material is used to bond them by heating. Further, at the upper end of the pipe portion 6a of the tip-pressure introducing pipe joined body 6, the main body portion 1 before joining is joined.
Positioning portion 1 positioned in the receiving recess 21 provided in 0
7 is provided, and the step 17a is provided.
Is formed by plastic working or cutting during processing of the pressure introducing pipe 5, and is used for vertically positioning the tip-pressure introducing pipe assembly 6 with respect to the main body 10.

On the other hand, the main body 10 includes a stem pedestal 18 and
The stem pedestal 18 is provided with the signal output pin 9a sealed with the sealing material 12, and the main body portion 10 and the pipe portion 6a of the tip-pressure introducing pipe joined body 6 are joined (second portion).
Is preferably performed using an energy beam such as a laser or an electron beam, and at this time, the chip 4 is not adversely affected by heat (cracking of the chip 4, deterioration of temperature characteristics, etc.). Therefore, it is desirable to irradiate the energy beam from the side A opposite to the pressure-sensitive tip 2 of the tip-pressure introducing pipe joined body 6 toward the second joined portion 8.

Next, an example of the manufacturing process of the semiconductor pressure sensor is shown in FIG. In step n1 of FIG. 3, processing of the stem pedestal 18, processing of the signal output pin 9a, drilling processing of the glass wafer 3A (FIG. 2A), circuit formation on the upper surface of the silicon wafer 2A, and lower surface processing of the silicon wafer 2A. Diaphragm formation is performed, and then the process proceeds to step n2 to bond the glass wafer 3A and the silicon wafer 2A (see FIG. 2).
After performing (b)), the process proceeds to step n3, and chips 4 are obtained by dicing the bonded body (wafer bonded body) of the glass wafer 3A and the silicon wafer 2A (FIG. 2).
(C) (d)). Next, in step n4, the tip 4 and the pressure introducing pipe 5 are preliminarily joined at the first joining portion 7 to obtain the tip-pressure introducing pipe joined body 6 which is a basic component. Then, in step n5, the pipe portion 6a of the tip-pressure introducing pipe joined body 6 is inserted into the insertion cylinder portion 15 formed in the main body portion 10. At this time, since the positioning step 17a is provided on the upper portion of the pipe portion 6a in a protruding manner, the step portion 17a is fitted into the receiving recess 21 provided in the main body portion 10, so that the pipe portion 6a before the joining is formed. It is possible to easily position the portion 10 in the vertical direction. Next, the second joint portion 8 between the main body portion 10 and the tip-pressure introducing pipe joint body 6 is joined by local heating with an energy beam. After that, the process proceeds to steps n6 and n7 in order to perform wire bonding 1
1 to the step of connecting the signal output pin 9a and the pressure-sensitive chip 2 and the step of mounting the housing. In addition, in the semiconductor pressure sensor 1B of the type installed by screwing shown in FIG. 4B, the step of mounting the substrate 13 in the main body 10 is inserted between steps n5 and n6.

In this way, the tip 4 (pressure-sensitive tip 2, glass pedestal 3) and the pressure introducing pipe 5 are connected to each other by the first joint portion 7.
Is joined in advance to obtain the tip-pressure introducing pipe joined body 6, and the tip-pressure introducing pipe joined body 6 is used as a basic component for the main body portion 10 in which the signal output pin 9a is integrated and the tip-pressure introducing pipe Since the pipe portion 6a of the pipe joined body 6 is joined at the second joint portion 8, the chip 4
It becomes easy to make the joining method between the main body 10 and the main body 10 common and the parts of the main body 10 common. That is, in the semiconductor pressure sensor, although the chip portion 6b has almost the same shape depending on the pressure to be measured and its environment, the body portion 10 has various materials and shapes from plastic to metal. However, as in the present embodiment, since the tip-pressure introduction pipe joined body 6 in which the tip 4 and the pressure introduction pipe 5 are joined in advance is used as a basic component and this is joined to the main body portion 10, a method is adopted. , A jig for joining the chip to the main body as in the past is not necessary, and a joining method (adhesive, soldering, etc.) according to the main body is also unnecessary. As a result, the joining method and the parts Can be easily standardized, and the manufacturing cost can be reduced. Moreover, even at the time of the first bonding between the chip 4 and the metal (pressure introducing pipe 5), there are restrictions due to the main body portion 10 (for example, if the main body portion 10 has a wire bonding portion, the bonding temperature cannot be raised, and Also, there is an advantage that the discoloration of the external appearance of the main body portion 10 is a problem and the bonding becomes impossible in an oxidizing atmosphere.

Another embodiment of the present invention is shown in FIGS. In the present embodiment, in the semiconductor pressure sensor 1A of the type installed by insertion, an insertion hole 15a into which the pipe portion 6a of the tip-pressure introduction pipe assembly 6 is inserted is formed in the center of the stem pedestal 18, and a signal is provided around it. A plurality of pin holes 25 into which the output pins 9a are inserted are formed, and the sealing material 12 is supplied to the gap between the pin holes 25 and the signal output pins 9a. Other configurations are similar to those of the embodiment of FIG.

An example of the manufacturing process of this semiconductor pressure sensor 1A is shown in FIG. After processing the stem pedestal 18 and the signal output pin 9a in step n1 of FIG. 7,
In step n2, the stem pedestal 18 and the signal output pin 9a are sealed and joined with the sealing material 12 (state of FIG. 5A), and then in step n3, the stem pedestal 18 is plated (Ni plating). , Au plating, etc.). afterwards,
In step n4, the tip-pressure introduction pipe joined body 6 obtained by joining the tip 4 and the pressure introduction pipe 5 (first joining) is used as a basic component to join the tip-pressure introduction pipe. The second joint portion 8 between the body 6 and the main body portion 10 is joined by local heating with an energy beam B such as a laser or electron beam (state shown in FIG. 5B). Finally, the process proceeds to steps n5 and n6 sequentially from the wire bonding process to the mounting process of the housing 60 (state of FIG. 5C). Here, the stem pedestal 18 and the signal output pin 9a are
Kovar or 42 alloy (trade name) having a linear expansion coefficient close to that of the sealing material is used. Further, it is desirable to oxidize the stem pedestal 18 and the signal output pin 9a in advance in order to improve the adhesion with the sealing material 12. The sealing is preferably performed in the air or nitrogen, and the sealing temperature is 1000 ° to 1
It is desirable that the temperature be 200 ° C. (depending on the type).
The sealing material 12 may be supplied in the form of paste, powder, or sintered material. Further, in order to facilitate the wire bonding 11 after removing the oxide, the signal output pin 9
After plating Ni on the surface of 1 to 10 μm, A on the outermost surface
It is desirable to plate u with 0.0 to 3 μm.

The second joint portion 8 between the main body portion 10 integrated with the signal output pin 9a and the tip-pressure introducing pipe joint body 6 which is the basic component is opposite to the pressure-sensitive tip 2. By adopting the method of locally heating with the energy beam B from the side A, there is no restriction such as the bonding temperature by the first bonding portion 7 when locally heating the second bonding portion 8, and Since the portion (second joint portion 8) separated from the chip 4 is melt-bonded, the thermal stress of the second joint portion 8 adversely affects the chip portion 6b (for example, cracking of the chip 4, deterioration of temperature characteristics, etc.). It has no effect.

By the way, in the semiconductor pressure sensor 1A of the type installed by insertion, when the second joint 8 is locally welded with the energy beam B from the side A opposite to the pressure sensitive tip 2 as shown in FIG. There is a problem that the pedestal 18 is heat-shrinked, cracks occur in the sealing material 12 that is a brittle material, and peeling occurs between the stem pedestal 18 and the sealing material 12. Therefore, when the second joining portion 8 is joined by local heating such as the energy beam B, as shown in FIGS. 9 and 10, it is preferable to provide a notch 30 for preventing heat shrinkage on the surface of the main body portion 10. desirable. That is, as shown in FIG. 9A, by providing a structure in which the cut 30 is provided on the lower surface of the main body 10 by pressing or cutting, the heat shrinkage can be absorbed by using the cut 30, and the sealing material 12 is provided. It becomes possible to relax the transmitted stress,
It is possible to effectively prevent the occurrence of cracks in the pin sealing portion. In addition. As the cross-sectional shape of the cut 30,
In addition to the V-shape shown in FIG. 9D, a polygonal cut 30 'shown in FIG. 9B or a U-shape cut 30 "shown in FIG. 9C may be used. The shape is not limited as long as it can be absorbed, and 90 is a rubber ring in FIG.

Yet another embodiment of the present invention is shown in FIG. In the present embodiment, in the semiconductor pressure sensor 1A of the type installed by insertion, the main body 10 is formed by resin molding, and at the same time, the signal output pin 9a is formed inside the resin.
Is to be incorporated. First, as shown in FIG. 11 (a), the signal output pin 9a is set between the upper die 40a and the lower die 40b of the molding die 40, and the tip portion 6b of the tip-pressure introducing pipe joined body 6 is raised. It is housed in the recess 40e of the die 40a, and the pipe portion 6a is inserted from the hollow portion 40c into the through hole 40d of the lower die 40b. The introduction pipe joined body 6 and the signal output pin 9a are integrally formed of resin (state of FIG. 11B). In this way, the main body 10 is formed by resin molding, and the main body 10
And tip-pressure introducing pipe joint 6 and signal output pin 9
By integrating a with resin, the manufacturing cost can be further reduced. The injection molding resin may be a thermoplastic resin such as a PBS resin or a PBT resin.

Still another embodiment of the present invention is shown in FIG. In the present embodiment, in the semiconductor pressure sensor 1B of the type installed by screwing, the metal main body 1
No. 0 insertion tube portion 15 and tip-pressure introduction pipe assembly 6
The second joint portion 8 with the pipe portion 6a is joined by local heating with the energy beam B from the side A opposite to the pressure sensitive tip 2 of the tip-pressure introducing pipe joint body 6. Reference numeral 13 in the figure denotes a substrate mounted on the main body 10, and is connected to the pressure-sensitive chip 2 via wire bonding (not shown). FIG. 4 shows another configuration.
This is similar to the embodiment of (b). Then, with the pipe portion 6a of the tip-pressure introducing pipe joined body 6 (basic component) inserted in the insertion cylinder portion 15 of the metal main body portion 10, the laser or the laser is applied from the side A opposite to the pressure-sensitive tip 2. By performing the method of joining the second joining portion 9 by local heating with the energy beam B such as the electron beam, when the second joining portion 9 is heated, the joining temperature by the first joining portion 7 and the like It is not restricted, and since the portion (second joint portion 8) apart from the pressure sensitive chip 2 is fusion-bonded,
The thermal stress of the joint does not adversely affect the chip portion 6b (crack of the chip 4, deterioration of temperature characteristics).

By the way, as shown in the second joint portion 8 of the metallic main body portion 10 in FIG. 12, generally, the corner portions of the metal member are chamfered, so that the melting range such as the energy beam B is changed. It is considered that welding defects are likely to occur in the extremely narrow joining method. Therefore, as shown in FIG. 13, the pipe portion 6 of the tip-pressure introducing pipe joined body 6 is provided on the inner surface of the distal end of the insertion tube portion 15 of the metal main body portion 10.
It is desirable to provide a small-diameter portion 50 for tightening a at the time of insertion before joining, and heat-join by irradiating the gap between the small-diameter portion 50 and the pipe portion 6a with an energy beam from the side opposite to the pressure-sensitive tip 2. . For example, by forging a small diameter portion 50 having a shape such that the circumference of the insertion tube portion 15 becomes smaller with a die or the like, the pipe portion 6a of the tip-pressure introducing pipe joined body 6 is not joined by the small diameter portion 50. The structure is tightened when inserting the
Therefore, even if the corners of the metal member are chamfered, welding is facilitated, and it is possible to reliably prevent defective welding at the second joint 9. In FIG. 13, 13 is a substrate, 9a is a signal output pin, and 60 is a housing.

Still another embodiment of the present invention is shown in FIG. In the present embodiment, the first joint 7 between the tip 4 (pressure-sensitive tip 2, glass pedestal 3) and the pressure introducing pipe 5 is
The bonding material having a thermal expansion coefficient close to that of the constituent material of the glass pedestal 3 or the pressure introducing pipe 5 is used for heat bonding in a furnace. Hereinafter, a low melting point glass (PbO) is used for the sealing material and the bonding material 100. The case of heat bonding using B ₂ O ₃ ) and the case of heat bonding using high melting point solder (Au-based, phosphorous copper braze) will be described separately.

First, when the low melting point glass (PbO.B ₂ O ₃ ) is heat-bonded to the sealing material or the bonding material 100, for example, the glass pedestal 3 and the wire are attached to the metal portion (pressure introducing pipe 5). Kovar or 42 alloy (trade name) having a similar expansion coefficient is used, and Pyrex glass (trade name) having a linear expansion coefficient close to that of silicon is used for the glass pedestal 3. The low-melting glass may be supplied in the form of paste, powder or sintered material. Then, the parts are set with a carbon jig or the like, and heated at a joining temperature of the low melting point glass of 400 to 600 ° C. (depending on the type) in the atmosphere or a nitrogen atmosphere using a tunnel furnace or a badge furnace to melt the low melting point glass. To join. By using the low melting point glass as a bonding material in this way, the coefficient of linear expansion matches that of the glass pedestal 3,
Thermal stress is reduced and heat resistance is also improved.

On the other hand, when a high melting point solder (Au type, phosphorous copper braze) is used for the encapsulating material and the joining material 100 by heat joining,
For the metal portion (pressure introducing pipe 5), for example, Kovar or 42 alloy (trade name) having a linear expansion coefficient close to that of the glass pedestal 3 is used, and Ni, Au two-layer plating or Ni single-layer plating is used in advance. It is desirable to apply. Also, three layers of a glass adhesion layer, a solder barrier layer, and a solder wetting layer (two layers of a glass adhesion layer and a solder barrier layer may be used if the solder wetting layer is unnecessary) are also formed on the bonding surface of the chip 4. May be applied by sputtering or the like. Pyrex glass (trade name) having a linear expansion coefficient close to that of silicon is used for the glass pedestal 3, and the bonding is performed in a mixed gas atmosphere of nitrogen or nitrogen hydrogen. Further, it is desirable to supply the high melting point solder without flux. Then, set the parts with a jig etc. and use a tunnel furnace or badge furnace to
It is heated at 00 ° C. (depending on the type) to melt the high melting point solder and bond it. At this time, the joining may be performed using a device such as a die bonder. Thus, by using a metal brazing material such as a high melting point solder as a joining material, the corrosion resistance is excellent and the heat resistance is also improved.

As yet another embodiment, as shown in FIG. 15, the first bonding portion 7 may be bonded by anodic bonding. For example, in the metal portion (pressure introducing pipe 5), Kovar or 42 having a linear expansion coefficient close to that of the glass pedestal 3 is used.
Alloy (product name) is used, and glass pedestal 3 is made of Pyrex glass (product name) having a linear expansion coefficient close to that of silicon. It is desirable that the surfaces to be joined are mirror-finished so that irregularities are suppressed to about several μm. Then, it is heated to 300 to 800 ° C. in vacuum or nitrogen, and DC voltage is 200 V to 100 V so that the metal side serves as an anode and the glass side serves as a cathode.
V is added and joined. Further, a low-melting glass or the like may be formed on the bonding surface by sputtering so as to facilitate bonding. By bonding the glass pedestal 3 and the pressure introducing pipe 5 (metal) by anodic bonding in this manner, a bonding material is not required, and the cost can be further reduced.

As still another embodiment, in addition to the structure in which the step 17a is provided on the pipe portion 6a of the tip-pressure introducing pipe joined body 6, as shown in FIG. 16 (a), a part of the pipe portion 6a is provided. 16B for positioning which is positioned on the main body 10 before joining, or a recess 17c which is positioned on the main body 10 before joining is provided in a part of the pipe portion 6a as shown in FIG. 16B. You may By thus providing the convex portion 17b or the concave portion 17c for positioning on the pipe portion 6a, not only the positioning in the vertical direction by the step 17a but also the convex portion 17b or the concave portion 1 is performed.
7c also enables positioning in the rotational direction, and as a result, the tip-pressure introducing pipe joined body 6 before joining.
It becomes easy to improve the positioning accuracy of the main body 10 with respect to the main body 10.

[0033]

As described above, in the semiconductor pressure sensor according to the invention of claim 1, the pressure sensitive chip for measuring the pressure of the fluid introduced from the outside is joined to the glass pedestal and the pressure sensitive chip. The tip and the pressure introducing pipe for introducing pressure to the tip are pre-joined at the first joining portion.
A pressure-introducing pipe joint is constructed, and the tip-pressure-introducing pipe joint is joined at a second joint to a main body portion having a signal output portion of the pressure-sensitive tip. By integrating the tip-pressure introduction pipe joined body that is pre-joined with the pipe into the main body as a basic component, there is no need for a jig or the like for joining the tip to the main body, which is required in the main body. There is no need for a bonding method (adhesive, soldering, etc.) that corresponds to this, and as a result, it is possible to standardize the bonding method between the chip and the main body and the common parts of the main body, and reduce costs. Becomes

The invention according to claim 2 is characterized in that when the second joint portion according to claim 1 is joined by local heating, a notch for preventing heat shrinkage is provided on the surface of the main body portion. In addition to the effect, even with a semiconductor pressure sensor of a type that is installed by insertion, the thermal stress of the main body can be relaxed by using the notch, and the occurrence of cracks in the sealing part of the signal output part can be effectively prevented. .

According to a third aspect of the present invention, the main body portion of the first aspect is provided with an insertion cylinder portion into which the pipe portion of the tip-pressure introducing pipe assembly is inserted, and an installation screw is provided on the outer surface side of the insertion cylinder portion. Since a small diameter portion is provided on the inner surface side of the insertion cylinder portion for tightening the pipe portion at the time of insertion before joining, and a gap between the small diameter portion and the pipe portion is used as the second joining portion. In addition to the effect described in Item 1, when the second joint is joined by welding, the gap between the welds is small, so that welding is facilitated and defective welding can be reliably prevented.

The invention according to claim 4 is characterized in that the pipe portion of the pipe assembly for tip-pressure introduction according to claim 1 or 3 is provided with a positioning portion which is positioned in the main body before joining. In addition to the effect of the third aspect, it is possible to easily position the tip-pressure introducing pipe joined body with respect to the main body portion in the vertical direction and the rotation direction by utilizing the positioning portion of the pipe portion.

According to a fifth aspect of the present invention, there is provided a semiconductor pressure sensor manufacturing method, wherein a pressure-sensitive chip for measuring the pressure of a fluid introduced from the outside and a glass pedestal are bonded to each other to obtain a chip. The tip and the pipe for pressure introduction for introducing pressure to the tip are pre-joined at the first joining portion.
The pressure-introducing pipe joined body is obtained, and thereafter, the main body portion provided with the signal output portion of the pressure-sensitive tip and the tip-pressure-introducing pipe joined body are joined at the second joining portion,
A tip-pressure introducing pipe joined body which is a basic component is formed in advance, and thereafter, a second joining portion between the tip-pressure introducing pipe joined body and the main body portion is connected to the first joining portion such as a joining temperature. It can be joined without any restrictions.

According to a sixth aspect of the present invention, the second joint portion between the tip-pressure introducing pipe joint body and the main body portion according to the fifth aspect is a pressure-sensitive tip of the tip-pressure introducing pipe joint body. Since the heating and joining are performed by irradiating the energy beam from the opposite side, in addition to the effect according to claim 5, the second joining portion between the tip-pressure introducing pipe joined body which is a basic component and the main body portion. By irradiating an energy beam from the side opposite to the pressure-sensitive tip of the tip-pressure introduction pipe joined body, the second joining is performed by local heating without being restricted by the joining temperature of the first joining portion. Can be joined. In addition, at the time of the first joining of the chip and the pressure introducing pipe, there are restrictions due to the main body (for example, if there is a wire bonding portion in the main body, the joining temperature cannot be raised, and discoloration of the appearance of the main body is a problem. Therefore, it becomes impossible to join in an oxidizing atmosphere).

According to the invention of claim 7, the first joint part of claim 5 is heat-bonded by using a metal brazing material or a bonding material having a linear expansion coefficient close to that of the low melting point glass, and the first bonding part of claim 5 is heat-bonded. In addition to the effect, in the case of the metal brazing material, the corrosion resistance is excellent, in the case of the low melting point glass, the thermal stress is small, and in any case, the heat resistance is good.

According to the invention of claim 8, the first bonding portion of claim 5 is bonded by anodic bonding.
In addition to the effects described above, a bonding material is not needed, and the cost can be further reduced. Further, the invention according to claim 9 is characterized in that the main body part of claim 5 is provided with an insertion cylinder part into which the pipe part of the tip-pressure introducing pipe assembly is previously inserted, and is installed on the outer surface side of the insertion cylinder part. In addition to the effect of claim 5, since the threaded portion is formed and the gap between the insertion cylinder portion and the pipe portion is heated and joined by irradiating an energy beam from the side opposite to the pressure-sensitive tip. Even if the semiconductor pressure sensor is of a type installed by screwing, the bonding of the second bonding portion can be bonded by local heating without being restricted by the bonding temperature of the first bonding portion. It will be possible.

According to the tenth aspect of the invention, in addition to the effect of the fifth aspect, the main body portion is formed of resin by molding the main body portion of the fifth aspect by resin molding, and at the same time, the main body portion is made of metal. Compared with the case of being manufactured, the main body portion and the signal output portion can be easily integrated, and the cost can be further reduced.

[Brief description of the drawings]

FIG. 1 shows an example of an embodiment of the present invention, (a) is a cross-sectional view of a tip-pressure introducing pipe joined body, and (b) is a tip-pressure introducing pipe joined body and a body portion after joining. FIG.

2A to 2D are explanatory views of a manufacturing process.

FIG. 3 is a flow chart of the above manufacturing process.

FIG. 4A is a sectional view showing an insertion type semiconductor pressure sensor, and FIG. 4B is a sectional view showing a screwing type semiconductor pressure sensor.

5A to 5C are explanatory views of another example of the manufacturing process.

6 (a) and 6 (b) are a plan view and a sectional view of the stem pedestal, respectively, and FIGS. 6 (c) and 6 (d) are a side view and a plan view of a signal output pin.

FIG. 7 is a flowchart of the manufacturing process of the above.

8A and 8B are explanatory diagrams of local heating by an energy beam.

FIG. 9A is a cross-sectional view showing still another embodiment of the present invention, and FIGS. 9B to 9D are enlarged cross-sectional views for explaining the aspect of the cut.

FIG. 10 is a cross-sectional view of the above finished product.

11A and 11B are cross-sectional views of still another example of the manufacturing process of the present invention.

FIG. 12 is a sectional view of still another embodiment of the present invention.

13A is a sectional view of still another embodiment of the present invention, and FIG. 13B is a sectional view after assembly.

14 (a) and 14 (b) are cross-sectional views of an example of a joining method for the first joining portion.

15 (a) and 15 (b) are cross-sectional views of another example of the method for joining the first joints.

16A is a cross-sectional view of a tip-pressure introducing pipe joined body, FIG. 16B is an explanatory diagram of a convex portion, and FIG. 16C is an explanatory diagram of a concave portion.

FIG. 17 is a sectional view of a conventional semiconductor pressure sensor.

FIG. 18A is a cross-sectional view of a main part of a conventional semiconductor pressure sensor, and FIG. 18B is a cross-sectional view of a main part of another conventional semiconductor pressure sensor.

FIG. 19 is a flowchart of the manufacturing process of FIG.

[Explanation of symbols]

 2 Pressure Sensitive Tip 3 Glass Pedestal 4 Chip 5 Pressure Introducing Pipe 6 Chip-Pressure Introducing Pipe Joint 6a Pipe Part 7 First Joint 8 Second Joint 9 Signal Output 10 Main Body 15 Insert Tube 16 Installation screw-in part 17 Positioning part 30 Notch 50 Small diameter part

Claims (10)

[Claims] 1. A first joint between a tip formed by joining a glass pedestal to a pressure-sensitive tip for measuring the pressure of a fluid introduced from the outside and a pressure-introducing pipe for introducing pressure into the pressure-sensitive tip. Is joined in advance to form a tip-pressure introducing pipe joined body, and the tip-pressure introducing pipe joined body is joined to the main body portion having the signal output portion of the pressure-sensitive tip at the second joining portion. A semiconductor pressure sensor characterized by being formed. 2. The semiconductor pressure sensor according to claim 1, wherein when the second joining portion is joined by local heating, a notch for preventing heat shrinkage is provided on the surface of the main body portion. 3. A main body part is provided with an insertion cylinder part into which a pipe part of a tip-pressure introduction pipe assembly is inserted, a screwing part for installation is provided on an outer surface side of the insertion cylinder part, and the insertion cylinder part of the insertion cylinder part is provided. 2. The semiconductor pressure sensor according to claim 1, wherein a small diameter portion is provided on the inner surface side for tightening the pipe portion at the time of insertion before joining, and a gap between the small diameter portion and the pipe portion serves as a second joining portion. . 4. The semiconductor pressure sensor according to claim 1, wherein the pipe portion of the tip-pressure introducing pipe joined body is provided with a positioning portion that is positioned in the main body portion before joining. 5. A pressure-sensitive tip for measuring the pressure of a fluid introduced from the outside is joined to a glass pedestal to obtain a tip, and this tip and a pressure-introducing pipe for introducing pressure to the pressure-sensitive tip are provided. The tip-pressure introducing pipe joined body is obtained by pre-joining at the first joining portion, and then the main body portion provided with the signal output portion of the pressure-sensitive tip and the tip-pressure introducing pipe joined body are provided as the second body. A method for manufacturing a semiconductor pressure sensor, which comprises joining at a joining portion. 6. A second joint between the tip-pressure introducing pipe joint and the main body is heated by irradiating an energy beam from the side opposite to the pressure-sensitive tip of the tip-pressure introducing pipe joint. The method for manufacturing a semiconductor pressure sensor according to claim 5, wherein the bonding is performed. 7. The method of manufacturing a semiconductor pressure sensor according to claim 5, wherein the first joint portion is heat-bonded by using a metal brazing material or a bonding material having a linear expansion coefficient close to that of the low melting point glass. 8. The method for manufacturing a semiconductor pressure sensor according to claim 5, wherein the first joint portion is joined by anodic joining. 9. The main body part is provided with an insertion cylinder part into which the pipe part of the tip-pressure introduction pipe assembly is previously inserted, and a threaded part for installation is formed on the outer surface side of the insertion cylinder part. 6. The method of manufacturing a semiconductor pressure sensor according to claim 5, wherein the gap between the insertion tube portion and the pipe portion is heated and joined by irradiating an energy beam from the side opposite to the pressure sensitive tip. 10. The method of manufacturing a semiconductor pressure sensor according to claim 5, wherein the main body portion is formed by resin molding, and at the same time, the signal emitting portion is incorporated inside the resin.