JP7283695B2 - SOUND SENSOR MANUFACTURING METHOD - Google Patents

Description

The present invention relates to a method of manufacturing a sound wave sensor suitable for detecting sound waves emitted from a detection target such as a mechanical device.

Many mechanical devices are installed in a factory that manufactures electronic components and the like. By the way, in order to prevent these mechanical devices from suddenly stopping due to failure, it is desirable to be able to detect an abnormal state and perform maintenance before they stop.

For example, many mechanical devices are equipped with rotating mechanisms such as motors, and it is known that when an abnormality occurs in the rotating mechanism, the intensity and frequency band of sound waves in the ultrasonic range emitted from these mechanical devices change. ing. Therefore, a device is used that monitors the sound waves in the ultrasonic range emitted from the mechanical device and detects that an abnormal state has been reached. An abnormality prediction device of this type is described in Patent Document 1, for example.

JP-A-5-209782

In general, anomaly detection using a sound wave sensor is performed by keeping a constant distance between a detection target such as a mechanical device and the sound wave sensor, and monitoring changes over time in sound waves emitted from the detection target. Here, in order to eliminate variations in the distance between the detection target and the sound wave sensor, it is preferable to fix the detection target.

In addition, when a large sonic sensor is fixed to the detection target, the sound collection space between the detection target and the sonic sensor becomes large, and acoustic resonance occurs in this space in a frequency band close to the frequency band of the detection signal, resulting in anomaly prediction. There is a problem that it becomes difficult to detect the detection signal for The present invention solves such problems, and provides a method for manufacturing a compact sound wave sensor that can be reliably adhered to a position a predetermined distance away from a detection target and that can obtain a desired detection signal. intended to

In order to achieve the above object, the invention according to claim 1 of the present application provides a method for manufacturing a sound wave sensor that forms a sound collecting space through which sound waves emitted from a detection target pass and is adhered to the detection target via an adhesive member. a step of preparing an aggregate substrate having a plurality of sensor chip mounting portions and adhesive member forming portions arranged to surround the respective sensor chip mounting portions; and mounting a sensor chip on each of the sensor chip mounting portions. a step of forming the adhesive member in each of the adhesive member forming portions; and a step of cutting and individualizing the aggregate substrate provided with the adhesive member surrounding at least the sensor chip. characterized by

The invention according to claim 2 of the present application is the method for manufacturing the acoustic wave sensor according to claim 1,
The collective substrate is characterized in that a recess is formed in the sensor chip mounting portion .

According to claim 3 of the present application, in the method of manufacturing the acoustic wave sensor according to claim 1 or 2, the step of forming the adhesive member includes forming an assembly of adhesive members on the adhesive member forming portion. and the step of singulating is a step of cutting the aggregate of the adhesive member together with the aggregate substrate to singulate.

According to the present invention, it is possible to easily provide a sound wave sensor that can be adhered without variation with a constant relative positional relationship between the sound wave sensor and the sound wave generation source, and that can suppress variation in detection signals caused by this variation. can be formed.

In addition, since the size of the sound wave sensor can be made small, the sound collection space between the detection target and the sound wave sensor becomes small, and the frequency of acoustic resonance in this space can be shifted to the high frequency band side. can. As a result, it is possible to form a highly sensitive sound wave sensor that reliably senses a detection signal. In particular, when the object to be detected is a mechanical device, even sound waves in the ultrasonic range emitted from the object to be detected can be detected.

The method of manufacturing an acoustic wave sensor according to the present invention can be configured with only a simple process of forming a plurality of acoustic wave sensors on an aggregate substrate and then separating them into individual pieces, and has the advantage of being able to form acoustic wave sensors at low cost. There is In particular, a method of preparing an aggregate of adhesive members and sticking this aggregate to an aggregate substrate is preferable because the work time can be shortened compared to the method of individually arranging the adhesive members at predetermined positions.

It is explanatory drawing of the manufacturing method of the acoustic wave sensor of 1st Example of this invention. It is explanatory drawing of the manufacturing method of the sound wave sensor of the 2nd Example of this invention. It is explanatory drawing of the manufacturing method of the sound wave sensor of the 3rd Example of this invention. 1 is an illustration of a sound wave sensor formed according to the present invention; FIG.

The present invention is a method of manufacturing an acoustic wave sensor capable of forming a small acoustic wave sensor provided with an adhesive member by forming a plurality of acoustic wave sensors on an aggregate substrate and then dividing the substrate into individual pieces. Examples of the present invention will be described in detail below.

A first embodiment of the present invention will be described with respect to a method of manufacturing a sound wave sensor for detecting sound waves in the ultrasonic range. First, the collective board 1 is prepared. As the aggregate substrate 1, a flat organic substrate used in a general semiconductor device manufacturing process can be used. As will be described later, on the assembly substrate 1, wires and electrodes connected to the acoustic wave sensor chips and the like are formed so that the sensor chip mounting portions on which the sensor chips and the like are mounted and the adhesive member forming portions surrounding the sensor chip mounting portions are arranged in a matrix. It is In the following description, illustration of wiring, electrodes, etc. is omitted.

A sensor chip 2 is mounted on the sensor chip mounting portion of the collective substrate 1 . The sensor chip 2 is a MEMS microphone element sensitive to the desired frequency band, ie the ultrasonic range in this embodiment. In the example shown in FIG. 1A, an IC chip 3 forming an integrated circuit for processing the output signal of the MEMS microphone element is also mounted on the sensor chip mounting portion. Three sensor chip mounting portions are formed on the collective substrate 1, and the sensor chip 2 and the IC chip 3 are mounted on each of them. The integrated circuit that processes the output signal can be integrated with the sensor chip 2, or it can have a structure that is not provided in the acoustic wave sensor, and it may not be mounted on the collective substrate 1. FIG.

Next, an adhesive member 4 is formed on the adhesive member forming portion so as to surround the sensor chip 2 and the like. A magnet can be used for this adhesive member in order to adhere it to a mechanical device or the like to be detected. For example, the magnet may be a sintered magnet or a plastic magnet molded into a desired shape surrounding the opening of the sensor chip mounting portion, and adhered to the bonding member forming portion. In the case of a sintered magnet, which is difficult to cut into individual pieces, as shown in FIG. The surface of the collective substrate 1 should be exposed to the surface.

The area surrounded by the adhesive member 4 is covered with a protective cover 5 for waterproofing, dustproofing, etc. (FIG. 1b). A metal mesh structure may be added to the protective cover 5 for electromagnetic shielding. It is also possible to fix the protective cover 5 by arranging another magnet on the protective cover 5 and using it as another adhesive member 4a. Alternatively, another adhesive member 4a may be made of a soft magnetic material such as iron. Alternatively, the protective cover 5 can be glued to the adhesive member 4, and another adhesive member 4a can also be glued to the protective cover 5 with glue. This separate adhesive member 4a not only has the function of fixing the protective cover 5, but also has the function of arranging the surface of the protective cover 5 away from the surface of the detection target while the sound wave sensor is adhered to the detection target. have. However, if the height is increased, the acoustic space becomes larger, so it is necessary to set the height appropriately so as to obtain the desired characteristics.

The surface of the sound wave sensor of this embodiment is adhered to the object to be detected during use. Therefore, the protective cover 5 is not necessarily required, and a structure without the protective cover 5 or a structure covered with a metal mesh that provides only an electromagnetic shielding effect is also possible. Without the protective cover 5, the separate adhesive member 4a is also unnecessary.

Next, singulation is performed. When singulating using a dicing saw 7 , the surface side of the collective substrate 1 on which a plurality of acoustic wave sensors are formed is attached to the dicing tape 6 . After that, a dicing saw 7 is run in a grid pattern so as to pass between the adhesive members 4, and a part of the collective substrate 1 is cut, thereby singulating into individual acoustic wave sensors (FIG. 1c).

A sound wave sensor formed in this manner is shown in FIG. According to this embodiment, it is possible to easily form a very small acoustic wave sensor.

When the sound wave sensor formed according to the present invention is used by adhering it to the detection target with the adhesive member 4 and another adhesive member 4a, the space (sound collection space) between the sound wave sensor and the detection target becomes very small, and the detection It is possible to move the acoustic resonance that makes it difficult to detect the signal to the higher frequency band side than the detection signal, and it is possible to improve the sensitivity of the detection signal in the ultrasonic band.

Next, a second embodiment will be described. The sensor chip 2 is mounted on the sensor chip mounting portion of the collective substrate 1 as in the first embodiment described above. An IC chip 3 forming an integrated circuit is also mounted. The state shown in FIG. 2(a) is the same state as FIG. 1(a) described in the first embodiment.

Next, an adhesive member 4 is formed on the adhesive member forming portion so as to surround the sensor chip 2 and the like. A magnet can be used for the adhesive member 4 so as to adhere to a mechanical device or the like to be detected. In the present embodiment, this magnet is a plastic magnet which is molded into a desired shape such that the sensor chip mounting portion is opened and surrounds the periphery thereof. As shown in FIG. 2(b), the adhesive member 4 is arranged in a region excluding the sensor chip mounting portion. This adhesive member 4 can be formed in a sheet form as an assembly of adhesive members 4 having through holes formed at positions corresponding to the sensor chip mounting portions. Therefore, it is possible to easily form the adhesive member 4 by laminating and bonding the sheet-like adhesive member 4 on the collective substrate 1 .

The area surrounded by the adhesive member 4 is covered with a protective cover 5. - 特許庁The protective cover 5 is adhered to the adhesive member 4 using another adhesive member 4a as in the first embodiment described above. When the separate adhesive member 4a is composed of a magnet, it is preferably composed of a plastic magnet. Another adhesive member 4a can also be sheet-shaped. Similarly to the first embodiment, the protective cover 5 and the separate adhesive member 4a are not necessarily required.

Next, singulation is performed. A dicing tape 6 is attached to the surface side of the collective substrate 1 on which a plurality of sound wave sensors are formed. After that, the dicing saw 7 is run in a grid pattern to cut a part of the aggregate substrate 1, the adhesive member 4, the protective cover 5, and another adhesive member 4a, so that individual acoustic wave sensors can be singulated ( Figure 2c).

Since the adhesive member 4 and another adhesive member 4a are cut by the dicing saw 7 when singulating as described above, the adhesive member 4 and the like are made of a plastic magnet that can be easily cut. Therefore, the magnet is not limited to a plastic magnet, and may be a sintered magnet as long as it can be separated into pieces. It is also possible to use a sintered magnet only for the separate adhesive member 4, or to use a sintered magnet that is not in the form of a sheet but in a separated state.

A sound wave sensor formed in this manner is shown in FIG. 4(b). Also in this embodiment, as in the first embodiment, it is possible to easily form a very small acoustic wave sensor. In the sound wave sensor formed according to this embodiment, the space (sound collection space) between the sound wave sensor and the detection target is also very small, and the acoustic resonance that makes it difficult to detect the detection signal is moved to the high frequency band side of the detection signal. It becomes possible to improve the sensitivity of the detection signal in the ultrasonic band.

In the present embodiment, while it was necessary to control the dicing saw 7 to run accurately between the adjacent adhesive members 4 during singulation in the first embodiment, the dicing saw 7 has a relatively wide width. Since the adhesive member 4 is cut, the cutting process is facilitated.

A third embodiment will now be described. In the above-described first and second embodiments, the bonding member forming portion is formed by bonding the bonding member 4 onto the plate-shaped collective substrate 1 . On the other hand, in the present embodiment, a concave portion 8 is formed in a part of the surface of a flat plate-shaped aggregate substrate 1, and the inside of this concave portion 8 is used as a sensor chip mounting portion, and the aggregate substrate 1 constituting the wall portion 9 is used as an adhesive member. forming part (Fig. 3a). That is, the wall portion 9 is composed of an organic substrate.

A sensor chip 2 is mounted on the sensor chip mounting portion in the recess 8 . An IC chip 3 forming an integrated circuit is also mounted. After that, the area surrounded by the wall portion 9 is covered with the protective cover 5 . A sheet-like one is used for this protective cover 5 . The protective cover 5 is adhered to the wall 9 using an adhesive. An adhesive member 4b is adhered onto the protective cover 5 with an adhesive. In this embodiment, the adhesive member 4b is a magnet, which is composed of a plastic magnet or a magnet sheet. The adhesive member 4b can also be sheet-like. Although the protective cover 5 is not necessarily required in this embodiment, the adhesive member 4b is essential even if the protective cover 5 is not provided. This is because the adhesive member 4b is used to adhere to a mechanical device or the like to be detected.

Next, singulation is performed. A dicing tape 6 is attached to the surface side of the collective substrate 1 on which a plurality of acoustic sensors are formed. After that, the dicing saw 7 is run in a grid pattern to cut the walls 9, the protective cover 5 and part of the adhesive member 4b of the collective substrate 1, thereby singulating into individual acoustic wave sensors (Fig. 3c). ).

Since the adhesive member 4b is cut with a dicing saw 7 when separating into individual pieces, it is made of a plastic magnet that can be easily cut. Therefore, the magnet is not limited to a plastic magnet, and may be a sintered magnet as long as it can be separated into pieces. It is also possible to use a sintered magnet that is not in a sheet form but in a separated state.

A sound wave sensor formed in this way is shown in FIG. 4(c). Also in this embodiment, as in the first and second embodiments, it is possible to easily form a very small acoustic wave sensor. In the sound wave sensor formed according to this embodiment, the space (sound collection space) between the sound wave sensor and the detection target is also very small, and the acoustic resonance that makes it difficult to detect the detection signal is moved to the high frequency band side of the detection signal. It becomes possible to improve the sensitivity of the detection signal in the ultrasonic band. The sound wave sensor of this embodiment has a structure in which the bonding member 4b is arranged only on the surface, but there is no problem in bonding it to the object to be detected.

A fourth embodiment will now be described. In the above-described first to third embodiments, the configuration in which the adhesive members 4, 4a, and 4b made of a hard material are arranged on the surface of the object to be detected has been described. By the way, the surface of the object to be detected is also made of a hard material. When hard materials are joined to each other, gaps are formed, and there is concern that noise may enter through the gaps, or noise may be generated due to the gaps. Therefore, a layer made of a viscoelastic material may be formed on the surface of the sound wave sensor that is directly adhered to the surface of the object to be detected, specifically on the surfaces of the adhesive members 4, 4a, and 4b. FIG. 4(d) shows an example in which a layer 10 made of a viscoelastic material is added to the acoustic sensor of the third embodiment. Alternatively, a layer made of a viscoelastic material may be formed instead of the joining member 4a. If it is difficult to cut the layer 10 made of the viscoelastic material using a dicing saw, the layer 10 made of the viscoelastic material may be formed and cut by using a normal printing method, or the viscoelastic material may be cut after cutting. It is also possible to form a layer 10 consisting of

Although the present invention has been described above, it goes without saying that the present invention is not limited to these. For example, the sound wave signal of the present invention is not limited to detecting signals in the ultrasonic range. The collective substrate is also not limited to organic substrates.

Further, the method of adhering the sound wave sensor to the object to be detected is not limited to magnetic force, and a well-known adhesion method such as an adhesive member can be employed. Further, depending on the surface shape of the object to be detected, it may not be possible to adhere the sound wave sensor without gaps. In that case, it is sufficient to add a part such that the sensor chip 2 is oriented in a desired direction and adhere it to the object to be detected without gaps. Furthermore, it is possible to add a member that blocks noise from directions other than the sensing direction.

1: Collective substrate, 2: Sensor chip, 3: IC chip, 4, 4a, 4b: Adhesive member, 5: Protective cover, 6: Dicing tape, 7: Dicing saw, 8: Concave portion, 9: Wall portion, 10: layer of viscoelastic material

Claims (3)

In a method for manufacturing a sound wave sensor that forms a sound collecting space through which sound waves emitted from a detection target pass and is adhered to the detection target via an adhesive member,
a step of preparing an aggregate substrate having a plurality of sensor chip mounting portions and adhesive member forming portions arranged so as to surround the respective sensor chip mounting portions;
mounting a sensor chip on each of the sensor chip mounting portions;
forming the adhesive member on each of the adhesive member forming portions;
A method of manufacturing an acoustic wave sensor, comprising: cutting the assembly substrate provided with the adhesive member surrounding at least the sensor chip into individual pieces. In the method for manufacturing an acoustic wave sensor according to claim 1,
A method of manufacturing an acoustic wave sensor , wherein the assembly substrate has a recess formed in the sensor chip mounting portion . In the method for manufacturing an acoustic wave sensor according to claim 1 or 2,
The step of forming the adhesive member is a step of forming an assembly of the adhesive members on the adhesive member forming portion;
A method of manufacturing an acoustic wave sensor, wherein the step of singulating is a step of cutting the aggregate of the adhesive member together with the aggregate substrate to singulate.

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