JP2007263677A - Semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate the downsizing of a semiconductor device equipped with a semiconductor chip comprising a thin-film like diaphragm that vibrates according to pressure fluctuation. <P>SOLUTION: This semiconductor device 1 is disposed on a mounting surface 3a of a circuit substrate 3. This semiconductor device 1 includes a semiconductor chip 7 and a circuit chip 5 disposed on the mounting surface 3a of the circuit substrate 3 for controlling the semiconductor chip 7. The circuit chip 5 includes through electrodes 11 put through the circuit substrate 3 from a rear surface 5b standing opposite to the mounting surface 3a of the circuit substrate 3 to a front surface 5a standing opposite to the semiconductor chip 7. The semiconductor chip 7 is layered/disposed on the front surface 5a of the circuit chip 5 with the diaphragm 29 caused to stand opposite to the circuit chip 5. Connection terminals 35 provided on an opposite surface 7b of the semiconductor chip 7 standing opposite to the circuit chip 5 is electrically connected to the through electrodes 11 by being put into contact therewith. The semiconductor chip 7 and the circuit chip 5 are bonded to each other without gaps by means of an annular resin sheet 37 disposed around the diaphragm 29. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor device including a semiconductor chip such as a sound pressure sensor chip or a pressure sensor chip.

  Conventionally, in a semiconductor device such as a silicon microphone or a pressure sensor, a semiconductor chip having a diaphragm for detecting pressure fluctuations such as sound by vibration is mounted on the surface of a circuit board, such as a sound pressure sensor chip or a pressure sensor chip. (For example, refer to Patent Document 1). In a state where this kind of semiconductor chip is arranged on the surface of the circuit board, a cavity is formed between the diaphragm and the surface of the circuit board.

Also, when the volume of the cavity is small, the air spring constant of the cavity is increased and the diaphragm is less likely to vibrate, so that the displacement of the diaphragm is reduced and pressure fluctuations cannot be detected accurately. That is, it is necessary to vibrate the diaphragm to ensure a sufficient size as the cavity. Further, the volume of the cavity needs to be changed as appropriate according to the characteristics of the semiconductor chip. In the conventional semiconductor device, the volume of the cavity is increased by forming a recess recessed from the surface of the circuit board.
In the semiconductor device having the above-described configuration, the circuit chip for controlling the semiconductor chip is mounted on the surface of the circuit board side by side with the semiconductor chip.
JP-T-2004-537182

However, in the conventional semiconductor device, since the semiconductor chip and the circuit chip are arranged on the surface of the circuit board, there is a problem that the size of the circuit board becomes large and it is difficult to reduce the size of the semiconductor device.
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a semiconductor device that can be easily reduced in size.

In order to solve the above problems, the present invention proposes the following means.
According to a first aspect of the present invention, there is provided a semiconductor device disposed on a circuit board mounting surface, wherein the semiconductor chip includes a thin film diaphragm that vibrates in response to pressure fluctuations, and is disposed on the circuit board mounting surface. A circuit chip that controls the semiconductor chip, and the circuit chip includes a through electrode that penetrates from the back surface facing the mounting surface of the circuit board to the surface facing the semiconductor chip, and the semiconductor chip passes through the diaphragm A connection terminal provided on the surface of the semiconductor chip facing the circuit chip is in contact with the through electrode and is electrically connected to the circuit chip in a state of being opposed to the circuit chip. The semiconductor chip and the circuit chip are bonded to each other without a gap by an annular resin sheet disposed around the diaphragm. It has proposed a semiconductor device that.

  According to the semiconductor device of the present invention, a hollow cavity is formed between the diaphragm and the surface of the semiconductor chip by disposing the semiconductor chip so that the diaphragm faces the surface of the circuit chip. . And since a semiconductor chip and a circuit chip are adhere | attached without a clearance gap by a cyclic | annular resin sheet, the above-mentioned cavity part is sealed with respect to the outer side of a semiconductor device. Here, since the size of the cavity can be easily set according to the size and shape of the resin sheet formed in advance, the volume of the cavity is prevented from changing unexpectedly during the manufacture of the semiconductor device. Thus, the vibration characteristics of the diaphragm can be prevented from changing.

  In addition, since a semiconductor device having a configuration in which a semiconductor chip and a circuit chip are stacked is arranged on the mounting surface of the circuit board, the semiconductor chip and the circuit board can be electrically connected through the through electrode, so that There is no need to separately mount the semiconductor chip and the circuit chip on the circuit board. Therefore, the semiconductor device can be easily reduced in size, and the mounting area of the semiconductor device with respect to the mounting surface of the circuit board can be reduced.

  The invention according to claim 2 proposes a semiconductor device according to claim 1, wherein the resin sheet is formed of a softer resin material than the semiconductor chip and the circuit chip. ing.

  The invention according to claim 3 is the semiconductor device according to claim 1 or 2, wherein the connection terminal and the through electrode are arranged to face each other, and the resin sheet has conductivity in a thickness direction. In addition, a semiconductor device is proposed which is made of an anisotropic conductive film having an insulating property in a direction along the surface and is disposed between the connection terminal and the through electrode.

According to the semiconductor device of the present invention, the anisotropic conductive film is used as the resin sheet for bonding the semiconductor chip and the circuit chip, so that the through electrode and the connection terminal are brought into contact with each other through the resin sheet for electrical connection. That is, the through electrode and the connection terminal can be joined by the anisotropic conductive film. Therefore, it is not necessary to prepare a separate joining member for joining the through electrode and the connection terminal, and electrical connection between the through electrode and the connection terminal can be easily performed.
In addition, by using an anisotropic conductive film, it is possible to easily prevent the through electrodes adjacent to each other and the connection terminals from being electrically connected to each other. Therefore, between the adjacent through electrodes or between the connection terminals The pitch can be reduced.

According to a fourth aspect of the present invention, in the semiconductor device according to any one of the first to third aspects, a concave portion that is recessed from the surface is formed on the surface of the circuit chip that faces the diaphragm. The semiconductor device characterized by this is proposed.
According to the semiconductor device of the present invention, the volume of the cavity defined by the diaphragm and the circuit chip can be increased by forming the recess recessed from the surface of the circuit chip.

  According to a fifth aspect of the present invention, in the semiconductor device according to any one of the first to fourth aspects, the upper surface, the circuit chip, and the periphery of the semiconductor chip are fixed to the upper surface of the semiconductor chip. A semiconductor device is proposed in which an opening for exposing the diaphragm to the outside is formed in the lid member.

In the semiconductor device according to the present invention, when pressure fluctuation such as sound reaches the diaphragm through the opening of the lid member, the diaphragm of the semiconductor chip vibrates based on the pressure fluctuation, so that the pressure fluctuation is reduced. Can be detected. Here, since the semiconductor chip, the circuit chip, and the bonded portion thereof are covered with the lid member, the semiconductor device can be easily protected. Since the lid member is fixed to the semiconductor chip, the semiconductor device can be easily mounted on the mounting surface of the circuit board while protecting the semiconductor device in a state where the laminated semiconductor chip and circuit chip are covered with the lid member. can do.
Furthermore, since the inside dimension of the lid member can be substantially equal to the size of the semiconductor chip or circuit chip, the semiconductor device can be protected while preventing the semiconductor device from becoming large.

The invention according to claim 6 proposes a semiconductor device according to claim 5, wherein the lid member is formed by forming an insulating film on a surface of a conductive member. .
According to the semiconductor device of the present invention, by electrically connecting the conductive member of the lid member to the ground pattern of the circuit board, electromagnetic noise that attempts to enter the inside of the lid member from the outside is blocked. Since the electromagnetic shield can be formed, it is possible to reliably prevent noise from reaching the semiconductor chip or the circuit chip.
Further, by forming the insulating coating, it is possible to easily prevent the electrical circuit of the semiconductor chip or the circuit chip from being short-circuited by the lid member.

According to the invention of claim 1, since the semiconductor device is configured by stacking the semiconductor chip and the circuit chip, the semiconductor device can be easily reduced in size and the semiconductor device on the mounting surface of the circuit board can be reduced. The mounting area can be reduced.
In addition, since the volume of the cavity can be prevented from changing unexpectedly during the manufacture of the semiconductor device and the vibration characteristics of the diaphragm can be prevented from changing, the yield of the semiconductor device can be improved, and the semiconductor device can be manufactured. Efficiency can be improved.

  According to the invention which concerns on Claim 2, the stress which generate | occur | produces between the semiconductor chip and circuit chip which were mutually adhere | attached can be relieve | moderated by deformation | transformation of a resin sheet.

According to the invention which concerns on Claim 3, since a penetration electrode and a connection terminal can be joined by an anisotropic conductive film, the electrical connection with a penetration electrode and a connection terminal can be performed easily.
Further, since the pitch between adjacent through electrodes or between connection terminals can be reduced, the semiconductor chip and the circuit chip can be further reduced in size.

According to the invention which concerns on Claim 4, since the volume expansion of a cavity part can be aimed at simply by forming a recessed part in a circuit chip, it can suppress that a diaphragm becomes difficult to vibrate. Therefore, pressure fluctuations such as sound can be detected with high accuracy by vibration of the diaphragm.
Further, since it is not necessary to form a recess for enlarging the cavity in the circuit board as in the prior art, there is no need to increase the thickness dimension of the circuit board in consideration of strength and the like, and the semiconductor device is mounted. It is possible to easily reduce the thickness of the circuit board.

According to the invention which concerns on Claim 5, protection of a semiconductor device can be aimed at, preventing the enlargement of a semiconductor device by providing a cover member.
Further, since the lid member is fixed to the semiconductor chip, the semiconductor device can be easily mounted on the mounting surface of the circuit board while protecting the semiconductor device.

  According to the sixth aspect of the present invention, in order to reliably prevent electrical noise generated on the outer side of the semiconductor device from reaching the semiconductor chip, malfunction of the semiconductor chip or circuit chip based on the noise is reliably ensured. Can be prevented.

1 and 2 show an embodiment of the present invention. As shown in FIGS. 1 and 2, the semiconductor device 1 according to this embodiment is configured to be mounted on a circuit board 3, and an LSI chip (circuit chip) disposed on the mounting surface 3 a of the circuit board 3. 5, a silicon microphone chip (semiconductor chip) 7 stacked on the surface 5 a side, and a lid member 9 that covers the LSI chip 5 and the silicon microphone chip 7. Here, the LSI chip 5 and the silicon microphone chip 7 are formed in the same size. That is, in a state where the LSI chip 5 and the silicon microphone chip 7 are stacked, the silicon microphone chip 7 does not protrude from the side of the LSI chip 5.
The LSI chip 5 has a through electrode 11 that penetrates from the back surface 5 b facing the mounting surface 3 a of the circuit board 3 to the front surface 5 a facing the silicon microphone chip 7 and electrically connects the silicon microphone chip 7 to the circuit board 3. The LSI chip body 13 is formed on the front surface 5a side, and the wiring package part 15 is formed on the back surface 5b side.

The LSI chip body 13 is made of, for example, silicon and plays a role of controlling the silicon microphone chip 7. That is, the LSI chip body 13 includes, for example, an amplifier circuit for amplifying an electric signal from the silicon microphone chip 7, a DSP (digital signal processor) for processing the electric signal as a digital signal, an A / D converter, and the like. Is included.
The LSI chip body 13 is provided with through vias 17 that penetrate in the thickness direction and are exposed on the front surface 5 a and the back surface 13 b of the LSI chip body 13. The through via 17 is configured by forming a metal wiring portion 17b made of a conductive material in a through hole 17a penetrating in the thickness direction of the LSI chip main body 13, and the metal wiring portion 17b is formed in the LSI chip main body 13. It is exposed to the front surface 5a and the back surface 13b. The metal wiring portion 17b is also formed at a position where the through hole 17a and the LSI chip body 13 overlap in the thickness direction.

The wiring package unit 15 includes an insulating layer 19 that covers the back surface 13 b of the LSI chip body 13, and a wiring unit 21 that is sealed by the insulating layer 19 and wires the metal wiring unit 17 b of the through via 17 to the back surface 5 b of the LSI chip 5. It has. That is, the through electrode 11 described above is constituted by the through via 17 and the wiring portion 21.
The wiring portion 21 is configured by a rewiring layer 23 formed on the back surface 13 b of the LSI chip body 13 and a copper post 25 extending from the rewiring layer 23 to the back surface 5 b of the LSI chip 5. The tip of the copper post 25 is exposed outward from the back surface 5b of the LSI chip 5 made of the insulating layer 19, and a solder ball 27 is attached to the tip. These solder balls 27 are used to join the through electrodes 11 of the LSI chip 5 to the electrode pads 3 b formed on the mounting surface 3 a of the circuit board 3.
Although not shown, the wiring package portion 15 is also sealed with a chip wiring portion for wiring the electric circuit of the LSI chip body 13 to the back surface 5b of the LSI chip 5. This chip wiring portion is constituted by the same rewiring layer and copper post as the wiring portion 21.

The silicon microphone chip 7 is a silicon sound pressure sensor chip that converts sound into an electrical signal. That is, the silicon microphone chip 7 includes a diaphragm 29 that vibrates in response to pressure fluctuations such as sound from an outer space located outside the semiconductor device 1. The diaphragm 29 is configured to vibrate in the thickness direction of the silicon microphone chip 7. The silicon microphone chip 7 has a recess 31 that is recessed from the surface (upper surface) 7 a thereof, and the bottom surface of the recess 31 is constituted by the diaphragm 29. The recess 31 is formed by, for example, silicon etching.
The silicon microphone chip 7 is disposed on the surface 5 a of the LSI chip 5 with the diaphragm 29 facing the LSI chip 5. A recess 33 that is recessed from the surface 5a is formed on the surface 5a of the LSI chip 5 that faces the diaphragm 29 of the silicon microphone chip 7.

A connection terminal 35 protrudes from the back surface (facing surface) 7b of the silicon microphone chip 7 facing the front surface 5a of the LSI chip 5. The connection terminal 35 is configured by providing stud bumps 35b protruding from electrode pads 35a formed on the back surface 7b. Here, the stud bump 35b is a protrusion structure having a height of 30 to 40 μm formed by a bonding wire manufacturing method, and is formed of gold (Au).
The connection terminal 35 configured in this manner is disposed to face the metal wiring portion 17b of the through via 17 exposed on the surface 5a of the LSI chip 5 so as to be electrically connected to the through electrode 11 of the LSI chip 5. It has become. More specifically, the connection terminal 35 is opposed to the metal wiring portion 17b disposed at a position overlapping the through hole 17a.
That is, the silicon microphone chip 7 can be electrically connected to the circuit board 3 through the through electrode 11. Further, when the connection terminal 35 is disposed on the metal wiring portion 17 b of the through via 17, a gap due to the stud bump 35 b is formed between the front surface 5 a of the LSI chip 5 and the back surface 7 b of the silicon microphone chip 7. become.

An annular resin sheet 37 disposed around the diaphragm 29 is provided between the through electrode 11 of the LSI chip 5 and the connection terminal 35 of the silicon microphone chip 7. The resin sheet 37 plays a role of adhering the LSI chip 5 and the silicon microphone chip 7, and has an anisotropic conductive film (ACF) having conductivity in the thickness direction and insulation in the direction along the surface. Anisotropic Conductive Film).
This anisotropic conductive film is configured to include conductive particles having conductivity in a resin material softer than the LSI chip 5 and the silicon microphone chip 7. Here, the resin material is made of, for example, an epoxy resin, a polyimide resin, or the like, and the conductive particles are made of, for example, plastic particles or Ni particles subjected to gold plating or silver plating.

The LSI chip 5 and the silicon microphone chip 7 are bonded to each other with a resin material constituting the resin sheet 37 without a gap, and the through electrode 11 and the connection terminal 35 are mutually connected via conductive particles contained in the resin sheet 37. Is in contact with and is electrically connected.
Therefore, in a state where the LSI chip 5 and the silicon microphone chip 7 are stacked, a hollow cavity S1 is formed between the diaphragm 29 and the LSI chip 5. The cavity S1 is configured by a gap between the front surface 5a of the LSI chip 5 and the back surface 7b of the silicon microphone chip 7 surrounded by the resin sheet 37, and a recess 33 that is recessed from the front surface 5a of the LSI chip 5. Here, since the LSI chip 5 and the silicon microphone chip 7 are bonded to each other by the resin sheet 37 without a gap, the cavity S1 is sealed against the outside of the semiconductor device 1.

  The lid member 9 is configured to cover the surface 7 a of the silicon microphone chip 7 and the periphery of the LSI chip 5 and the silicon microphone chip 7. That is, the lid member 9 is fixed to the surface 7 a of the silicon microphone chip 7 with the adhesive 39, and extends from the periphery of the bottom wall 41 in the stacking direction of the LSI chip 5 and the silicon microphone chip 7. It is composed of a cylindrical part 43 surrounding the periphery of the chip 5 and the silicon microphone chip 7. The bottom wall 41 is formed with an opening 41a that exposes the silicon microphone chip 7 to the outside.

The inner dimension of the lid member 9 is substantially equal to the size of the stacked LSI chip 5 and silicon microphone chip 7. That is, the bottom wall portion 41 of the lid member 9 is disposed opposite to the surface 7a of the silicon microphone chip 7 with the adhesive 39 interposed therebetween, and the cylindrical portion 43 of the lid member 9 is disposed on the LSI chip 5 and the silicon microphone chip. 7 is disposed opposite to the side surface of the 7 through a minute gap.
The lid member 9 is formed by forming an insulating coating 9b on the surface of the conductive member 9a formed in the above-described shape. Specifically, the insulating coating 9b is formed by performing alumite treatment on the conductive member 9a made of aluminum.

When manufacturing the semiconductor device 1 configured as described above, first, the resin sheet 37 is temporarily fixed to the surface 5 a of the LSI chip 5 located around the recess 33. At this time, the resin sheet 37 is also disposed on the metal wiring portion 17 b of each through via 17. Further, at the same time as or before and after the resin sheet 37 is temporarily fixed, a stud bump 35 b is formed on the electrode pad 35 a of the silicon microphone chip 7 to constitute the connection terminal 35.
Next, the silicon microphone chip 7 is laminated on the surface 5 a of the LSI chip 5 with each connection terminal 35 facing the metal wiring portion 17 b of each through via 17.

At this time, the resin sheet 37 is heated while applying pressure from the silicon microphone chip 7 side. As a result, the resin material constituting the resin sheet 37 is melted and the stud bump 35b sinks into the resin sheet 37, and the conductive particles of the resin sheet 37 face each other between the metal wiring portion 17b and the stud bump 35b. It will be sandwiched between them. As described above, the LSI chip 5 and the silicon microphone chip 7 are bonded and fixed to each other, and the through electrodes 11 and the connection terminals 35 are electrically connected.
Finally, the lid member 9 is placed on the LSI chip 5 and the silicon microphone chip 7, and the bottom wall portion 41 of the lid member 9 is fixed to the surface 7 a of the silicon microphone chip 7 via the adhesive 39, thereby allowing the semiconductor device 1. Is completed.

When the semiconductor device 1 manufactured as described above is mounted on the circuit board 3, the solder chip 27 is in contact with the electrode pad 3 b while the back surface 5 b of the LSI chip 5 is opposed to the mounting surface 3 a. The semiconductor device 1 is pressed against the circuit board 3 while heating the balls 27. As a result, the semiconductor device 1 is fixed to the mounting surface 3 a of the circuit board 3 and the LSI chip 5 and the silicon microphone chip 7 are electrically connected to the circuit board 3.
In this semiconductor device 1, when a pressure fluctuation such as sound reaches the diaphragm 29 of the silicon microphone chip 7 through the opening 41 a of the lid member 9, the diaphragm 29 vibrates based on this pressure fluctuation, The pressure fluctuation can be detected.

According to the semiconductor device 1 described above, the semiconductor device 1 having a configuration in which the silicon microphone chip 7 and the LSI chip 5 are stacked is disposed on the mounting surface 3 a of the circuit board 3, and the silicon microphone chip 7 and the silicon microphone chip 7 are interposed via the through electrode 11. Since the circuit board 3 can be electrically connected, it is not necessary to separately mount the silicon microphone chip 7 and the LSI chip 5 on the circuit board 3 as in the prior art. Therefore, the semiconductor device 1 can be easily downsized and the mounting area of the semiconductor device 1 on the mounting surface 3a of the circuit board 3 can be reduced. Specifically, the semiconductor device 1 and the mounting area can be the size of the chip size package.
Further, since the size of the cavity S1 formed between the diaphragm 29 and the LSI chip 5 can be easily set according to the size and shape of the resin sheet 37 formed in advance, the size of the semiconductor device 1 It is possible to prevent the volume of the cavity S1 from changing unexpectedly during manufacturing, and to prevent the vibration characteristics of the diaphragm 29 from changing. Therefore, the yield of the semiconductor device 1 can be improved and the manufacturing efficiency of the semiconductor device 1 can be improved.

Furthermore, by forming the recess 33 in the LSI chip 5, it is possible to easily increase the volume of the cavity S1, so that it is possible to suppress the diaphragm 29 from being difficult to vibrate. Therefore, pressure fluctuations such as sound can be accurately detected by the vibration of the diaphragm 29.
Further, unlike the prior art, it is not necessary to form a recess for enlarging the cavity S1 in the circuit board 3, so that it is not necessary to increase the thickness dimension of the circuit board 3 in consideration of strength and the like. 1 can be easily reduced in thickness.

Further, by using an anisotropic conductive film as the resin sheet 37 for bonding the silicon microphone chip 7 and the LSI chip 5, the metal wiring portion 17 b of the through via 17 and the connection terminal 35 are brought into contact with each other through the resin sheet 37. The through via 17 and the connection terminal 35 can be joined by an anisotropic conductive film. Therefore, it is not necessary to prepare a separate joining member for joining the through via 17 and the connection terminal 35, and electrical connection between the through via 17 and the connection terminal 35 can be easily performed.
Also, by using an anisotropic conductive film, the through vias 17 adjacent to each other on the front surface 5a of the LSI chip 5 and the connection terminals 35 adjacent to each other on the back surface 7b of the silicon microphone chip 7 are electrically connected. Since the connection can be easily prevented, the pitch between the through vias 17 adjacent to each other or between the connection terminals 35 can be reduced. Therefore, the LSI chip 5 and the silicon microphone chip 7 can be further downsized.

In addition, since the resin material for forming the anisotropic conductive film and bonding the LSI chip 5 and the silicon microphone chip 7 to each other is softer than the LSI chip 5 and the silicon microphone chip 7, the LSI chip 5 bonded to each other. And the silicon microphone chip 7 can be relieved by deformation of the resin sheet 37.
Further, since the LSI chip 5, the silicon microphone chip 7, and their bonded portions are covered with the lid member 9, the semiconductor device 1 can be easily protected. Since the lid member 9 is fixed to the silicon microphone chip 7, the semiconductor device 1 can be easily protected while protecting the semiconductor device 1 in a state where the stacked LSI chip 5 and silicon microphone chip 7 are covered with the lid member 9. 1 can be mounted on the mounting surface 3 a of the circuit board 3.
Further, since the inner dimension of the lid member 9 can be made substantially equal to the size of the LSI chip 5 or the silicon microphone chip 7, the semiconductor device 1 can be protected while preventing the semiconductor device 1 from being enlarged.

Furthermore, since the lid member 9 is composed of the conductive member 9a, the conductive member 9a is electrically connected to the ground pattern of the circuit board 3 to attempt to enter the inside of the lid member 9 from the outside. An electromagnetic shield that blocks electromagnetic noise can be formed, and noise can be reliably prevented from reaching the LSI chip 5 and the silicon microphone chip 7. Therefore, malfunctions of the LSI chip 5 and the silicon microphone chip 7 due to noise can be reliably prevented.
Further, by forming the insulating coating 9b on the surface of the conductive member 9a, it is possible to easily prevent the electrical circuit of the LSI chip 5 or the silicon microphone chip 7 from being short-circuited by the lid member 9.

In the above embodiment, the semiconductor device 1 including the LSI chip 5 and the silicon microphone chip 7 of the same size has been described. However, the present invention is not limited to this, and the semiconductor device including the LSI chip and the silicon microphone chip of different sizes is used. Can be applied. That is, the silicon microphone chip 7 is formed in a size smaller than the LSI chip 5 as shown in FIG. 3, for example, so that the LSI chip 5 protrudes from the side of the silicon microphone chip 7. It doesn't matter.
In the case of this configuration, the stepped portion 51c is formed in the cylindrical portion 51 of the lid member 49 that covers the stacked LSI chip 5 and silicon microphone chip 7, so that the cylindrical portion 51 is connected to the LSI chip 5 and the silicon microphone. The chip 7 can be opposed to the side surface of the chip 7 with a small gap.

That is, the cylindrical portion 51 is disposed around the silicon microphone chip 7 and the cylindrical small-diameter portion 51a that is opposed to the side surface of the silicon microphone chip 7 through a minute gap. A cylindrical large-diameter portion 51b that opposes the side surface of the LSI chip 5 with a minute gap, and an annular step portion 51c that connects the small-diameter portion 51a and the large-diameter portion 51b.
If the size of the silicon microphone chip 7 is smaller than the LSI chip 5 as described above, the connection terminal 35 may be formed at a position shifted from the through hole 17a as shown in the figure. The metal wiring portion 17b may be formed to extend from the formation position of the through hole 17a to the position facing the connection terminal 35 on the surface 5a of the LSI chip 5. In this case, it is not necessary to form the metal wiring part 17b at a position overlapping the through hole 17a and the LSI chip 5 in the thickness direction.

For example, as shown in FIG. 4, the silicon microphone chip 7 is formed in a size larger than the LSI chip 5. That is, the silicon microphone chip 7 is formed in a size such that the silicon microphone chip 7 protrudes from the side of the LSI chip 5. It doesn't matter. In the case of this configuration, the cylindrical portion 55 of the lid member 53 may be formed so as to be opposed to the side surface of the silicon microphone chip 7 through a minute gap. In this case, a gap between the side surface of the LSI chip 5 facing each other and the cylindrical portion 55 becomes large.
In the case of this configuration, the connection terminal 35 is formed on the back surface 7b of the silicon microphone chip 7 so that the connection terminal 35 of the silicon microphone chip 7 faces the metal wiring portion 17b provided on the front surface 5a of the LSI chip 5. It is necessary to consider the position.

The lid members 9, 49, 53 are configured by forming the insulating coating 9b on the surface of the conductive member 9a. However, the present invention is not limited to this, and the lid members 9, 49, 53 are at least from the outside. Any structure may be used as long as it forms an electromagnetic shield that blocks electromagnetic noise that tends to enter the inside. That is, the lid member 9 may be formed of a conductive film made of, for example, a carbon microcoil.
Further, the LSI chip 5 is provided with the solder balls 27 protruding from the back surface 5b. However, the present invention is not limited to this, and at least a connection terminal for electrically connecting the LSI chip 5 to the circuit board 3 is provided. What is necessary is just to be provided in the said back surface 5b. In other words, for example, the copper post 25 may protrude from the back surface 5 b of the LSI chip 5.

Further, although the LSI chip 5 is composed of the LSI chip body 13 and the wiring package unit 15, the present invention is not limited to this, and for example, the LSI chip 5 may be composed of only the LSI chip body 13. In the case of this configuration, for example, the through electrode 11 is configured only by the through via 17.
Furthermore, although the resin sheet 37 is composed of an anisotropic conductive film, the present invention is not limited to this, and it is sufficient that it is composed of a resin material that is softer than at least the LSI chip 5 and the silicon microphone chip 7. However, in the case of this configuration, it is preferable to bond the through electrode 11 and the connection terminal 35 with a separate bonding member such as solder or a conductive adhesive. The conductive adhesive is mainly composed of a resin material such as an epoxy resin.

For example, when the above-described bonding is performed using the solder described above, the solder is printed in advance on the through vias 17 exposed on the surface 5a of the LSI chip 5, and then the resin sheet is attached to the LSI chip 5 in the same manner as in the above embodiment. Temporarily fasten to the surface 5a. Next, similarly to the above embodiment, the silicon microphone chip 7 is laminated on the surface 5a of the LSI chip 5, and the resin sheet and the solder are heated while applying pressure from the silicon microphone chip 7 side.
At this time, the stud bump 35b sinks into the resin sheet and comes into contact with the solder. In addition, since the solder is melted during this heating, the stud bump 35b and the through via 17 are joined by the solder.

Further, for example, when performing the above-described bonding using the above-described conductive adhesive, the conductive adhesive is previously attached to the stud bump 35b of the silicon microphone chip 7, and the resin sheet is used in the same manner as in the above embodiment. Temporarily fasten to the surface 5 a of the LSI chip 5. Next, as in the above embodiment, the silicon microphone chip 7 is laminated on the surface 5a of the LSI chip 5, and the resin sheet and the conductive adhesive are heated while applying pressure from the silicon microphone chip 7 side.
At this time, the stud bump 35b sinks into the resin sheet and comes into contact with the conductive adhesive. Further, since the resin material of the conductive adhesive is also melted during this heating, the stud bump 35b and the through via 17 are joined by the conductive adhesive.

Further, the LSI chip 5 is formed with a recess 33 that is recessed from the surface 5a and faces the diaphragm 29. However, the present invention is not limited to this, and the surface 5a of the LSI chip 5 constituting the cavity S1 and the silicon microphone are formed. If the gap with the back surface 7b of the chip 7 is large enough to detect pressure fluctuations such as sound with vibration of the diaphragm 29, it does not need to be formed.
In addition, the silicon microphone chip 7 is composed of a sound pressure sensor chip including the diaphragm 29. However, the present invention is not limited to this, and at least if the silicon microphone chip 7 has a movable part such as the diaphragm 29 constituting the silicon microphone chip 7. Good. Therefore, the semiconductor chip may be, for example, a pressure sensor chip that measures the pressure or pressure change in the outer space of the semiconductor device 1.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

It is a sectional side view showing the state where the semiconductor device concerning one embodiment of this invention was mounted in the circuit board. FIG. 2 is a side sectional view showing a state in which the semiconductor device of FIG. 1 is disassembled into a lid member, a silicon microphone chip, and an LSI chip. It is a sectional side view which shows the semiconductor device which concerns on other embodiment of this invention. It is a sectional side view which shows the semiconductor device which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Semiconductor device, 3 ... Circuit board, 3a ... Mounting surface, 5 ... LSI chip (circuit chip), 5a ... Front surface, 5b ... Back surface, 7 ... Silicon microphone Chip (semiconductor chip), 7a ... front surface (upper surface), 7b ... back surface (opposite surface), 9, 49, 53 ... lid member, 9a ... conductive member, 9b ... insulating coating , 11 ... Through electrode, 29 ... Diaphragm, 33 ... Recess, 35 ... Connection terminal, 37 ... Resin sheet, 41a ... Opening

Claims (6)

A semiconductor device disposed on a mounting surface of a circuit board,
A semiconductor chip having a thin film diaphragm that vibrates in response to pressure fluctuations, and a circuit chip that is disposed on a mounting surface of the circuit board and controls the semiconductor chip,
The circuit chip includes a through electrode penetrating from a back surface facing the mounting surface of the circuit board to a surface facing the semiconductor chip;
The semiconductor chip is disposed on the surface of the circuit chip in a state where the diaphragm faces the circuit chip,
A connection terminal provided on the facing surface of the semiconductor chip facing the circuit chip is in electrical contact with the through electrode,
The semiconductor device, wherein the semiconductor chip and the circuit chip are bonded to each other without a gap by an annular resin sheet disposed around the diaphragm.   The semiconductor device according to claim 1, wherein the resin sheet is formed of a resin material that is softer than the semiconductor chip and the circuit chip. The connection terminal and the through electrode are arranged to face each other,
The resin sheet is made of an anisotropic conductive film having conductivity in the thickness direction and insulating in the direction along the surface, and is disposed between the connection terminal and the through electrode. The semiconductor device according to claim 1 or 2.   4. The semiconductor device according to claim 1, wherein a concave portion that is recessed from the surface is formed on a surface of the circuit chip facing the diaphragm. 5. A lid member fixed to the upper surface of the semiconductor chip and covering the upper surface and the periphery of the circuit chip and the semiconductor chip;
The semiconductor device according to claim 1, wherein an opening that exposes the diaphragm to the outside is formed in the lid member. The semiconductor device according to claim 5, wherein the lid member is configured by forming an insulating film on a surface of a conductive member.

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