JP2000329632A - Pressure sensor module and method for manufacture it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a compact pressure sensor module that can be manufactured easily and inexpensively and has large bending strength. SOLUTION: A lead frame 4 where a circuit part for composing a pressure sensor and an IC chip 3 (chip parts 8) for composing the circuit part of a non- contact data carrier are mounted is subjected to transfer forming by an epoxy resin or the like, thus manufacturing a resin forming body. At this time, a cavity 6 where a lead frame surface for mounting a pressure sensor chip 2 is exposed to a bottom surface is formed at a resin forming body 5. The pressure sensor chip 2 is mounted into the cavity 6, a pressure transferring resin 7 such as a silicone resin is filled into the cavity 6, and the pressure sensor chip 2 is sealed by the resin. Then, an unneeded lead frame part is cut for calibrating the pressure sensor, thus obtaining a pressure sensor module 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pressure sensor module and a method for manufacturing the pressure sensor module.
Specifically, the structure of a pressure sensor module that is provided with a pressure sensor, has an IC chip as a main internal component, and is applicable to a non-contact data carrier that transmits and receives signals to and from an external device in a non-contact manner and the like. It relates to a manufacturing method.

[0002]

2. Description of the Related Art A pressure sensor usually takes the form of a variable capacitance component such as a variable capacitor or a variable resistor, and a pressure sensor chip whose capacitance changes according to a pressing force;
It is composed of an IC chip that converts pressure from the amount of change. External electronic components for performing various functions other than the pressure sensor chip and the IC chip are connected as necessary.

The pressure sensor is provided as a pressure sensor module sealed with a resin or the like in order to protect these internal components from external impact. A low-hardness silicone resin that does not hinder pressure transmission is used.

FIG. 7 is a sectional view of such a pressure sensor module 50.
Reference numeral 0 denotes a lead frame 54 on which a mounting substrate 53 and a pressure sensor chip 51 on which an IC chip 52 is mounted and other external electronic components (chip components), and two lead frames 54 configured to expose the lead frame 54. And a resin molded body 55 having cavities 56 and 57.

In one cavity 56, a pressure sensor chip 51, a chip pad of the pressure sensor chip 51 and a bonding pad on a lead frame 54 are mounted by bonding wires 59, and are filled with a pressure transmitting resin 61 such as silicone resin. ing. In the remaining one cavity 57, an IC chip 52 constituting a pressure sensor and other chip-type external electronic components such as an IC chip are similarly mounted by bonding wires 58 and the like, and a sealing resin 62 having strength such as epoxy resin is used.
Is cast to maintain the strength of the entire package.

[0006]

However, in the pressure sensor chip 51 having such a structure, since casting and curing are performed using two kinds of different resins 61 and 62, the number of steps is increased and the manufacturing cost is relatively high. Met. In addition, a sufficient cavity space must be provided in each of the two cavities 56 and 57 for performing wire bonding and chip mounting, resulting in an increase in package size.

Further, in order to impart bending strength and impact resistance, it is necessary to increase the height / area ratio of the package. Therefore, the entire package must be thickened, resulting in an increase in package size. Was the result.

Further, since the inside of the cavity 56 in which the pressure sensor chip 51 is mounted is filled with the silicone resin 61, this portion tends to be weak in bending.

The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a pressure sensor module which can be manufactured easily and inexpensively and has a reduced package size and a high bending strength. The purpose is.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above objects, the present invention provides a resin molded article having a cavity for accommodating a pressure sensor chip, while sealing an IC chip and other chip parts constituting a pressure sensor. After forming a pressure sensor chip, a pressure sensor chip is to be mounted in the cavity.

The pressure sensor module according to the first aspect of the present invention seals the pressure sensor IC chip and the chip component mounted on the back surface of the lead frame and has a cavity so that a part of the surface of the lead frame is exposed. And a pressure sensor chip is mounted on the lead frame surface in the cavity, and the cavity is filled with a pressure transmitting resin.

With this structure, a pressure sensor module can be easily obtained by manufacturing a package with a cavity in a conventional IC packaging process and mounting a sensor chip in the cavity. . Therefore, a pressure sensor module can be obtained simply and inexpensively. Further, since only the pressure sensor chip is mounted in the cavity, the package area can be reduced. As a result, the substantial package height / area ratio can be increased, and the bending strength can be increased.

Further, since the module is mounted on both sides, the strength at the pressure center chip portion is also increased.

In the pressure sensor module according to the present invention, the pressure sensor IC chip and the chip component mounted on one surface of the lead frame are sealed, and a part of the lead frame surface is exposed. There was a resin molded body in which a cavity was formed, a pressure sensor chip was mounted on the lead frame surface in the cavity, and the inside of the cavity was filled with a pressure transmitting resin.

With this pressure sensor module,
A pressure sensor module having high bending strength can be obtained simply and inexpensively as in the pressure sensor module according to the first aspect.

A pressure sensor module according to a third aspect of the present invention is the pressure sensor module according to the first aspect, on which an IC bare chip is mounted.

A pressure sensor module according to a fourth aspect of the present invention is the pressure sensor module according to the second aspect, on which an IC bare chip is mounted.

As described above, an IC bare chip can be used as an IC chip. For example, a pressure sensor module can be more easily obtained by COB mounting.

A pressure sensor module according to a fifth aspect of the present invention is the pressure sensor module according to any one of the first to fourth aspects, wherein an output value of the pressure sensor can be calibrated by an external terminal provided on a lead frame.

As described above, by making it possible to calibrate the output value of the pressure sensor using the external terminal, a highly reliable pressure sensor module can be provided.

According to a sixth aspect of the present invention, in the pressure sensor module according to the first to fourth aspects, the chip component is a non-contact data carrier IC chip, and an external terminal for connecting a non-contact data carrier antenna coil is provided. It is a pressure sensor module provided.

By using such a pressure sensor module, a non-contact data carrier with a pressure sensor can be easily and inexpensively provided. Also, installation location,
Depending on the application, it can be combined with various antenna coils.

According to a seventh aspect of the present invention, in the method of manufacturing a pressure sensor module, after the IC chip and the chip component for the pressure sensor are mounted on the surface of the lead frame, the IC chip and the chip component are sealed by transfer molding, and at the same time the lead is mounted. A method of manufacturing a pressure sensor module in which a resin molded body provided with a cavity that exposes a part of the back surface of the frame is formed, and then a pressure sensor chip is mounted in the cavity and then the cavity is filled with a pressure transmitting resin. It is.

According to this method, a pressure sensor module can be produced by one transfer molding for sealing the IC chip and the chip component with resin and two sealing steps for filling the cavity with a pressure transmitting resin. For this reason, the manufacturing process is simplified, and the pressure sensor module can be obtained at low cost. Further, according to the method, since the pressure sensor chip is resin-sealed after being molded, an extra impact is not applied to the pressure sensor chip, so that damage during the manufacturing process can be prevented.

In the method of manufacturing a pressure sensor module according to the present invention, the pressure sensor IC chip and the chip component are mounted on one surface of the lead frame, and the IC chip and the chip component are sealed by transfer molding. At the same time, a resin molded body having a cavity for exposing a part of the lead frame mounting surface is prepared, and then, after mounting the pressure sensor chip in the cavity, the pressure for filling the cavity with the pressure transmitting resin is formed. It is a manufacturing method of a sensor module.

In this method, as in the manufacturing method of the seventh aspect, the manufacturing process is simplified, and the pressure sensor module can be obtained at low cost. Further, it is possible to prevent the pressure sensor chip from being damaged during the manufacturing process.

Further, in the manufacturing method according to claim 9 of the present application,
In claim 7, an IC bare chip is mounted in the cavity.

According to a tenth aspect of the present invention, in the eighth aspect, an IC bare chip is mounted in the cavity.

According to these methods, a pressure sensor chip can be easily mounted, and a pressure sensor module can be easily manufactured.

[0030]

FIG. 1 is a sectional structural view of a pressure sensor module according to an embodiment of the present invention, FIG. 2 is a plan view showing a lead frame used in the pressure sensor module of FIG. 1, and FIG. FIG. 4 is an explanatory view showing a method for manufacturing a pressure sensor module, FIG. 4 is a plan view showing another lead frame used for the pressure sensor module, and FIG. 5 is a method for manufacturing a pressure sensor module according to another embodiment of the present invention. FIG. 6 is an explanatory view showing a method of manufacturing a pressure sensor module according to still another embodiment of the present invention. The details will be described below with reference to the drawings.

The pressure sensor module 1 shown in FIG.
The pressure sensor chip 2 and the IC chip 3 are mounted on the lead frame 4, and include a resin sealing portion 7 sealing the pressure sensor chip 2 and a resin molded body 5 sealing the IC chip 3.

The pressure sensor chip 2 only needs to have a structure capable of detecting the pressure applied to the pressure sensor module 1 itself, and its configuration, structure, size, etc. are not particularly limited.

The chip component 8 used in the pressure sensor module 1 according to the present invention is not particularly limited, and includes not only the IC chip 3 other than the IC chip 3 constituting the pressure sensor, but also a resistor and a capacitor associated therewith. Is mentioned. In the pressure sensor module 1 according to the present embodiment, the IC chip 3 has not only a circuit part constituting a pressure sensor but also an IC in which a circuit functioning as a transponder in a non-contact data carrier system is formed. Chip 3 is used.
Although FIG. 1 illustrates the IC chip 3 as a single chip component, it goes without saying that two or more chip components including the IC chip 3 may be used. This I
The C chip and the chip component may be mounted once after being made into a COB, or may be mounted directly on a frame.

In the pressure sensor module 1, a lead frame 4 as shown in FIG. 2 is used, and an IC chip 3 is mounted on one surface (front surface) and on the other surface (back surface). A pressure sensor chip 2 is mounted. The lead frame is provided with a calibration terminal for the pressure sensor. The IC chip 3 and the pressure sensor chip 2 are mounted on the lead frame 4 by wire bonding, respectively, and are of a double-sided mounting type.

The IC chip 3 is sealed by a resin molding 5. The resin molded body 5 is made of a resin material having sufficient mechanical strength, such as an epoxy resin, a phenol resin, a polyurethane, and an engineering plastic resin, for protecting the IC chip 3 and other chip components 8. Further, the resin molded body 5 is manufactured by transfer molding because of excellent mass productivity.
In order to obtain a high-strength, high-heat-resistant product, an epoxy resin, particularly a highly-filled epoxy resin having high mechanical strength, is suitably used as the resin material.

One cavity 6 is formed in the resin molded body 5. The cavity 6 is for mounting the pressure sensor chip 2 and sealing with a pressure transmitting resin. Therefore, the cavity 6 is provided on the back surface of the lead frame 4 (the surface on which the pressure sensor chip is mounted) so that the pressure sensor chip 2 can be mounted thereon.
Is formed.

The pressure sensor chip 2 is connected to the cavity 6
Implemented within. At this time, the semiconductor device is mounted on the lead frame 4 exposed from the bottom surface of the cavity 6 using the bonding wire 12. Thereafter, the pressure transmitting resin 7 is poured into the cavity 6 and the pressure sensor chip 2 is sealed with the resin.

The pressure transmitting resin 7 is a resin capable of transmitting a pressure applied from the surface of the resin to the pressure sensor chip 2 sealed in the cavity 6, and more specifically, a hardness such as a silicone resin. Is low and does not depend on external conditions such as temperature.

Next, a method of manufacturing the pressure sensor module 1 will be described in detail with reference to FIG. First,
As shown in FIG. 3A, for example, the IC chip 3 is mounted on a lead frame 4 as shown in FIG.

Next, the lead frame 4 on which the IC chip 3 is mounted is transfer-molded using an epoxy resin or the like, and a resin molded body 5 in which the IC chip 3 is sealed is first obtained.
At this time, as shown in FIG.
Is formed in the resin molded body 5 with its back surface exposed. The size of the cavity 6 must be large enough to mount the pressure sensor chip 2, but if it is larger than necessary, the package strength will be reduced.

After that, the resin molded body 5 is inverted, and the pressure sensor chip 2 is mounted on the lead frame 4 in the cavity 6 by the bonding wire 12. IC
The method for connecting the COB on which the chip components are mounted to the lead frame is not limited to wire bonding. For example, as shown in FIG. 4, the lead frame 4 provided with the solder bonding pad 11 may be used. It is also possible to adopt a method of performing solder bonding with a solder bonding pad on the back surface of the substrate.

Then, as shown in FIG. 3C, the pressure transmitting resin 7 is filled in the cavity 6 in which the pressure sensor chip 2 is accommodated, and the pressure sensor chip 2 is sealed. Finally, after removing the tie bars and unnecessary lead frames,
The pressure sensor sensitivity is calibrated to obtain the pressure sensor module 1 according to the present invention.

By forming the cavity 6 so that the pressure sensor chip 2 can be mounted on the resin molded body 5 in which the electronic components such as the IC chip 3 are sealed as described above, the IC chip 3 and the pressure The sensor chip 2 can be sealed. Further, since the pressure sensor chip 2 can be mounted in the cavity 6, the manufacturing process can be greatly simplified.

Since the pressure sensor chip 2 is sealed after sealing the IC chip 3 (and the chip component 8), the IC chip 3 is sealed without inadvertent impact on the pressure sensor chip 2. Can be stopped. Further, in the pressure sensor module 1 having the structure shown in FIG. 1, since the pressure sensor chip 2 and the IC chip 3 are mounted on the upper and lower surfaces of the lead frame 4, the thickness / area ratio increases. In addition, bending resistance and mechanical shock resistance can be improved.

As described above, according to the present invention, a compact and reliable pressure sensor module 1 can be manufactured inexpensively and easily.

Next, a method of manufacturing the pressure sensor module 1 shown in FIG. 5 will be described. In the pressure sensor module 1, the IC chip 3 and the pressure sensor chip 2 are mounted on the same surface of the lead frame 4.

The pressure sensor module 1 can be manufactured in the same manner as described above. That is, first, only the IC chip 3 is mounted on the lead frame 4 by using the lead frame 4 configured to mount the IC chip 3 and the pressure sensor chip 2 (FIG. 5A). Thereafter, the lead frame 4 on which the IC chip 3 is mounted is transfer-molded to obtain a resin molded body 5 in which the cavity 6 is formed.
(FIG. 5 (b)). After that, the pressure sensor chip 2 is mounted in the cavity 6 and sealed with the pressure transmitting resin 7.
(FIG. 5 (c)). Finally, the pressure sensor module 1 is obtained after the sensitivity of the pressure sensor is calibrated by removing the tie bars and unnecessary lead frame portions.

In the pressure sensor module 1, the IC chip 3 and the pressure sensor chip 2 are mounted on the same surface of the lead frame 4. In such a structure, a resin sealing layer for sealing the pressure sensor chip 2 and I
Since the resin molded body layers for sealing the C chip 3 can be formed with the same thickness, the thickness can be reduced without lowering the strength of the IC chip 3 mounting portion as compared with the pressure sensor module 1 shown in FIG. Thus, the present invention can greatly contribute to downsizing of the pressure sensor module 1 and simplification of the manufacturing method.

The present invention is not limited to the above embodiments, and various embodiments can be considered. In the pressure sensor module 1 shown in FIG. 6B, the IC chip 3 and other chip components 8 are mounted on a mounting substrate 9, and the mounting substrate 9 is further mounted on the lead frame 4. In this pressure sensor module 1, FIG.
As shown in (a), the IC chip 3 and the chip component 8 are mounted on the mounting substrate 9 in advance. In this manner, transfer molding can be performed after mounting the chip component 8 on the mounting substrate 9 in advance and mounting the chip component 8 on the lead frame 4 in the same manner as in the related art. Furthermore, after mounting the IC chip 3 and the chip component 8 on a lead film or a flexible circuit board, and the like, further mounting it on the lead frame 4, and then performing transfer molding to obtain the resin molded body 5 in which the cavity 6 is formed. You may do so. Of course, the method is not limited to the transfer molding, and the method is not limited to this method as long as the lead frame 4 on which the electronic component is mounted can be insert-molded and the resin molded body 5 in which the cavity 6 is formed can be obtained.

[0050]

Next, a pressure sensor module according to an embodiment of the present invention was manufactured by the method shown in FIG. First, a non-contact data carrier IC (and a chip component) incorporating a pressure sensor IC circuit is mounted on a copper alloy lead frame in which a bonding area is partially silver-plated, and an IC pad and a lead frame terminal are mounted by wire bonding. Was electrically connected. Next, transfer molding is performed at 180 ° C. for 2 minutes using an epoxy resin.
The resin sealing of the IC and the protection of the wire bonding were performed, and the cavity formation on the back surface was collectively performed.

Thereafter, the molding resin contamination of the pressure sensor chip mounting pad exposed in the cavity was removed by polishing. At this time, the polishing was performed under the condition that the plating process of the bonding pad of the lead frame was sufficiently maintained and the bonding strength was secured.

Next, after mounting the pressure sensor chip in the cavity and performing wire bonding, the inside of the cavity is filled with a silicone resin.
Cured in minutes. Finally, the tie bars of the lead frame were cut, leaving only the necessary external terminals of the lead frame to obtain a pressure sensor module. Thereafter, the pressure sensor was calibrated using the calibration external terminal, and an external coil was connected to the antenna coil connection terminal to obtain an internal component for a non-contact data carrier.

[0053]

According to the present invention, a pressure sensor module can be easily and inexpensively provided by obtaining a package with a cavity by a conventional method for manufacturing an IC package and mounting a sensor in the cavity.

In particular, by mounting the pressure sensor chip and the IC chip on both sides, a pressure sensor module having high bending strength can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional structural view of a pressure sensor module according to an embodiment of the present invention.

FIG. 2 is a plan view showing a lead frame used in the pressure sensor module shown in FIG.

FIGS. 3A, 3B and 3C are explanatory views showing a method for manufacturing the pressure sensor module shown in FIG.

FIG. 4 is a plan view showing another lead frame used for the pressure sensor module.

FIGS. 5A, 5B, and 5C are explanatory views showing a method for manufacturing a pressure sensor module according to another embodiment of the present invention.

FIGS. 6A and 6B are explanatory views showing a method of manufacturing a pressure sensor module according to still another embodiment of the present invention.

FIG. 7 is a cross-sectional view of a conventional pressure sensor module.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pressure sensor module 2 ... Pressure sensor chip 3 ... IC chip 4 ... Lead frame 5 ... Resin molding 6 ... Cavity 7 ... Pressure transmitting resin 8 ... Chip components 9 ... Mounting board 11 …… Pad part 12 …… Bonding wire

Claims (10)

[Claims] 1. A method for sealing a pressure sensor IC chip and a chip component mounted on a back surface of a lead frame,
A resin molded body having a cavity formed so that a part of the surface of the lead frame is exposed, a pressure sensor chip is mounted on the lead frame surface in the cavity, and the inside of the cavity has a pressure transmitting resin. Double-sided pressure sensor module filled with. 2. A resin molded article in which a pressure sensor IC chip and a chip component mounted on one surface of a lead frame are sealed, and a cavity is formed so that a part of the lead frame surface is exposed. A pressure sensor module comprising: a pressure sensor chip mounted on a lead frame surface in the cavity; and a cavity filled with a pressure transmitting resin. 3. The pressure sensor module according to claim 1, wherein the IC bare chip is mounted. 4. The pressure sensor module according to claim 2, wherein the IC bare chip is mounted. 5. The pressure sensor module according to claim 1, wherein an output value of the pressure sensor can be calibrated by an external terminal provided on the lead frame. 6. The pressure sensor module according to claim 1, wherein the chip component is a non-contact data carrier IC chip and has an external terminal for connecting a non-contact data carrier antenna coil. 7. A pressure sensor I on a lead frame surface.
After mounting the C chip and the chip component, a resin molded body having a cavity for sealing the IC chip and the chip component and simultaneously exposing a part of the back surface of the lead frame is formed by transfer molding. A method of manufacturing a pressure sensor module, comprising: mounting a pressure sensor chip in a cavity; and filling the cavity with a pressure transmitting resin. 8. After mounting the pressure sensor IC chip and the chip component on one surface of the lead frame, the IC chip and the chip component are sealed by transfer molding, and at the same time, a part of the lead frame mounting surface is exposed. A method of manufacturing a pressure sensor module in which a resin molded body having a cavity is formed, a pressure sensor chip is mounted in the cavity, and then the cavity is filled with a pressure transmitting resin. 9. The method according to claim 7, wherein an IC bare chip is mounted in the cavity. 10. The method according to claim 8, wherein an IC bare chip is mounted in the cavity.