JP2009014469A - Semiconductor device and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the cost of a semiconductor device. <P>SOLUTION: The semiconductor device comprises a semiconductor chip 2 having a minute movable sensor 2d being an MEMS sensor on a main surface 2a, a package substrate 1 supporting the semiconductor chip 2, a cap member 3 which is mounted on the semiconductor chip 2, has a cavity portion 3a, moreover covers the movable sensor 2d with the cavity portion 3a, and hermetically seals the movable sensor 2d, and a plurality of bump electrodes 7 provided on the rear face of the package substrate 1. The semiconductor chip 2 and the cap member 3 are joined by caulking bosses 4a made of soft metal formed on the main surface 2a of the semiconductor chip 2, and wedge-like recessions 3b formed in the cap member 3, to perform their engagement, and the movable sensor 2d is sealed hermetically in a vacuum state with the cavity portion 3a of the cap member 3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a semiconductor device and a manufacturing method thereof, and more particularly, to a semiconductor device having a MEMS (Micro Electro Mechanical Systems) element and a technique effective when applied to a manufacturing method thereof.

As a sealing structure of the capacitance type sensor, an electrode is formed at the center of the first substrate, a wiring extraction portion connected to the electrode is formed, and an electrode and an electrode extraction portion are similarly formed on the second substrate. The substrate 3 is made of a highly conductive material, the central weight is elastically supported by the beam from the periphery, these electrodes and the weight are arranged so as to face each other with a small gap, and the frit glass is melted to A technique for hermetically configuring the inside is disclosed (for example, see Patent Document 1).
JP 2000-310648 A

  A MEMS device such as a MEMS sensor needs to avoid moisture adsorption and gas viscosity because a minute beam structure and a movable body perform vibration and rotation with high accuracy. In addition, some of the detection parts of the sensor deteriorate in performance due to oxidation or gas adsorption.

  Therefore, the MEMS package (semiconductor device) needs to be hermetically sealed in a vacuum state or in an inert gas atmosphere.

  Generally used vacuum sealing is a technique called anodic bonding, in which silicon (Si) and glass are heated to about 300 to 400 ° C. with a hot plate or the like, and a high voltage of several hundred volts is applied and bonded. An inert gas encapsulation structure is formed.

  However, in the anodic bonding, there is a problem that the bonding material to be used is limited to silicon and glass and is restricted in terms of material. Furthermore, since a high voltage is applied in a high temperature state, there arises a problem that a MOS (Metal Oxide Semiconductor) device is deteriorated.

  In addition, as another hermetic sealing technique, a technique has been developed in which the surfaces of the materials are subjected to plasma treatment to join the materials together.

  However, in the plasma processing method, if the flatness and cleanliness of the material surface are poor, poor bonding occurs.

As another hermetic sealing technique, there is a method using a CVD (Chemical Vapor Deposition) film of PolySi or SiO ₂ as a sealing agent for a vacuum structure. However, the CVD sealing method is limited in application to the semiconductor pre-process, and after sealing, there is a problem that the sealed portion is destroyed by heat treatment or film stress during the process.

  As another hermetic sealing technique, there is a method of using a package using metal welding. However, the package using the metal welding has a problem of large-scale equipment and high cost.

  In addition, although the airtight method in the electrostatic capacitance type sensor of the said patent document 1 (Unexamined-Japanese-Patent No. 2000-310648) melt | dissolves glass, it is limited to using glass also in this case, and it is materially The problem of being constrained arises.

  An object of the present invention is to provide a technique capable of reducing the cost of a semiconductor device.

  Another object of the present invention is to provide a technique capable of simplifying the assembly process of a semiconductor device.

  Another object of the present invention is to provide a technique capable of improving the reliability of a semiconductor device.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in this application, the outline of typical ones will be briefly described as follows.

  That is, the present invention includes a semiconductor chip on which a minute movable element is formed, and a cavity part that is mounted on the semiconductor chip and covers the minute movable element by the cavity part, so that the minute movable element is hermetically sealed. A cap member and a plurality of external terminals electrically connected to the electrodes of the semiconductor chip, and a soft metal protrusion formed on one of the semiconductor chip and the cap member; The semiconductor chip and the cap member are joined to each other by a caulking recess formed in the other, and the micro movable element is hermetically sealed in a vacuum state or an inert gas atmosphere. is there.

  Further, the present invention provides a step of preparing a semiconductor chip on which a micro movable element is formed, a step of preparing a cap member on which a cavity portion is formed, and the semiconductor chip and the cap member. The soft metal protrusions and the recesses formed on the other are fitted by caulking to join the semiconductor chip and the cap member, and the cavity part covers the micro movable element and And a step of hermetically sealing the minute movable element in a vacuum state or an inert gas atmosphere.

  Of the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  Of the semiconductor chip on which the micro movable element is formed, and the cap member that hermetically seals the micro movable element, the soft metal protrusion formed on one of them and the recess formed on the other are caulked. The micro movable element is hermetically sealed using a semiconductor process without using a special assembly process because the micro movable element is hermetically sealed in a vacuum state or an inert gas atmosphere. For this reason, the micro movable element can be hermetically sealed at a reduced cost. As a result, the cost of the semiconductor device in which the minute movable element is hermetically sealed can be reduced.

  In addition, since the micro movable element is hermetically sealed using a normal semiconductor process, a high voltage is not applied in a high temperature state, and plasma processing is not performed, thereby improving the reliability of the semiconductor device. Can do.

  In the following embodiments, the description of the same or similar parts will not be repeated in principle unless particularly necessary.

  Further, in the following embodiment, when it is necessary for the sake of convenience, the description will be divided into a plurality of sections or embodiments, but they are not irrelevant to each other unless otherwise specified. The other part or all of the modifications, details, supplementary explanations, and the like are related.

  Also, in the following embodiments, when referring to the number of elements (including the number, numerical value, quantity, range, etc.), particularly when clearly indicated and when clearly limited to a specific number in principle, etc. Except, it is not limited to the specific number, and it may be more or less than the specific number.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments, and the repetitive description thereof will be omitted.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing an example of the structure of the semiconductor device according to the first embodiment of the present invention. FIG. 2 shows an example of the structure after hermetic sealing in the assembly of the semiconductor device shown in FIG. FIG. 3 is a cross-sectional view showing a structure cut along the line AA shown in FIG. 2, and FIG. 4 shows an example of the structure from sensor formation to cap member joining in the assembly of the semiconductor device shown in FIG. FIG. 5 is a process flow diagram showing an example of a structure up to cap member formation in the assembly of the semiconductor device shown in FIG. 1, and FIG. 6 is a structure in the dicing and die bonding steps in the assembly of the semiconductor device shown in FIG. FIG. 7 is a process flow diagram showing an example of a structure in a wire bonding and sealing process in the assembly of the semiconductor device shown in FIG. Is a sectional view showing a structural example after bump formation in the fabrication of the semiconductor device shown in FIG.

  A semiconductor device 12 according to the first embodiment shown in FIG. 1 has a semiconductor chip on which a MEMS element which is a minute and movable element is formed. In the first embodiment, the minute movable element is minutely movable. The case of a sensor will be described as an example. That is, the minute movable sensor 2d formed on the main surface 2a of the semiconductor chip 2 is a MEMS sensor, which is a silicon mechanical element that senses acceleration or vibration.

  The configuration of the semiconductor device 12 shown in FIG. 1 will be described. A semiconductor chip 2 which is a capacitive sensor having a beam structure and is a MEMS sensor formed on the main surface 2a and a semiconductor chip 2 are supported. A package substrate 1; a cap member 3 mounted on the semiconductor chip 2 and provided with a cavity 3a; and the cavity 3a covers the minute movable sensor 2d and hermetically seals the minute movable sensor 2d; A plurality of bump electrodes (external terminals) 7 provided on the back surface and electrically connected to the pads 2b which are electrodes of the semiconductor chip 2 via the wires 5, and a cap for sealing the semiconductor chip 2 and the plurality of wires 5 6 and.

  Furthermore, in the semiconductor device 12, the boss 4a, which is a soft metal protrusion formed on the main surface 2a of the semiconductor chip 2, and the wedge-shaped recess 3b formed on the cap member 3 are fitted by caulking. The semiconductor chip 2 and the cap member 3 are joined together.

  Further, when the minute movable sensor 2d is sealed by the cavity portion 3a of the cap member 3, the inside of the cavity portion 3a is hermetically sealed while maintaining the vacuum state by being sealed in a vacuum state. Yes.

  That is, the minute movable sensor 2d has a beam structure as shown in FIG. 1 and is arranged side by side in a comb shape as shown in FIG. 2, so that a small amount of acceleration and vibration change can be detected. The portion 3a is hermetically sealed so as to be in a vacuum state.

  If necessary, the inside of the cavity 3a may be hermetically sealed as an inert gas atmosphere.

  As described above, the semiconductor device 12 is obtained by hermetically sealing the minute movable sensor 2d, which is a MEMS sensor, by metal caulking.

  The semiconductor chip 2 and the cavity portion 3a are joined by plastically deforming a soft metal boss (projection portion) 4a formed on the main surface 2a of the semiconductor chip 2 into the concave portion 3b of the cap member 3 by caulking. Is what you do. Therefore, the boss 4a is preferably made of a soft material that easily undergoes plastic deformation, such as solder, gold (Au), indium (In), or copper (Cu).

When the boss 4a is formed, as shown in FIG. 4, as the adhesive layer 4b, the surface of the main surface 8a of the semiconductor wafer 8 is made of titanium (Ti), tungsten (W), chromium (Cr) or the like. A layer is formed and bonded to the oxide film (SiO ₂ ) on the surface of the main surface 8a by oxidation / reduction.

  Further, by using silicon (semiconductor) also for the cap member 3, when forming the cavity 3a and the recess 3b, it can be processed by wet etching or dry etching in a semiconductor process. That is, it is possible to hermetically seal the minute movable sensor 2d in the semiconductor device 12 using a semiconductor process and by caulking of metal processing.

  In addition, as shown in FIG. 4, it is preferable to form the recessed part 3b of the cap member 3 in a wedge shape. That is, it is preferable that the hole diameter be increased toward the back of the hole of the recess 3b.

  By making the hole shape of the recess 3b wedge-shaped, the bonding force between the boss 4a and the recess 3b can be increased, and therefore the bonding strength between the semiconductor chip 2 and the cap member 3 can be further increased. As a result, the airtightness in the cavity 3a can be further enhanced.

  As shown in FIG. 1, the micro movable sensor 2 d having a beam structure formed on the main surface 2 a of the semiconductor chip 2 is electrically connected to the pad 2 b via the internal wiring 2 c of the semiconductor chip 2. The pad 2b of the semiconductor chip 2 is electrically connected to the electrode of the package substrate 1 and the through-hole wiring 1a via the wire 5, and further to the bump electrode 7 which is an external terminal connected to the through-hole wiring 1a. Connected.

  Here, the wire 5 is a gold wire, for example.

  Next, a method for manufacturing the semiconductor device according to the first embodiment will be described with reference to the process flow diagrams of FIGS. 2, 3, and 4 to 8. Here, the assembly on a semiconductor wafer will be described as an example. At that time, as shown in FIGS. 2 and 3, two chip regions 8b on the semiconductor wafer 8 will be described as a representative.

  First, the MEMS sensor shown in step S1 of FIG. 4 is formed. Here, the minute movable sensor 2d which is a MEMS sensor having a beam structure as shown in FIGS. 2 and 4 is formed in the plurality of chip regions 8b of the semiconductor wafer 8 having the plurality of chip regions 8b on the main surface 8a.

  Thereafter, boss formation shown in step S2 is performed. Here, on the main surface 8a of the semiconductor wafer 8, bosses (projections) 4a made of soft metal and projecting from the main surface 8a are formed around each micro movable sensor 2d as shown in FIG. At that time, first, an adhesive layer 4b serving as an adhesive is formed. The adhesive layer 4b is a layer of titanium (Ti), tungsten (W), chromium (Cr), or the like, for example.

The adhesive layer 4b is bonded to the main surface 8a in order to perform oxidation / reduction with the oxide film (SiO ₂ ) on the surface of the main surface 8a of the semiconductor wafer 8.

  Thereafter, a boss 4a is formed on each adhesive layer 4b. The boss 4a is a soft metal that easily undergoes plastic deformation, such as solder, gold (Au), indium (In), or copper (Cu), and is bonded to each adhesive layer 4b.

  In addition, the formation process of the boss | hub 4a is equivalent to the gold bump formation process in a general semiconductor process formation process, and can be processed on a wafer, without using a special process.

  On the other hand, cap formation shown in step S11 of FIG. 5 is performed. Here, first, a cap wafer 9 which is a thin plate member made of a silicon wafer is prepared, and then a plurality of cavity portions 3a are formed in the cap wafer 9 as shown in the cap hole opening in step S12, and the cavity The cap member 3 is formed by forming the recess 3b at a position surrounding the portion 3a.

  The cavity 3a and the recess 3b can be formed by wet etching or dry etching in a semiconductor process. Moreover, it is preferable to form the recessed part 3b in a wedge shape. That is, it is preferable that the hole diameter be increased toward the back of the hole of the recess 3b. By making the hole shape of the concave portion 3b wedge-shaped, the bonding force between the boss 4a and the concave portion 3b can be increased, and the bonding strength between the semiconductor chip 2 and the cap member 3 can be further increased. As a result, the airtightness in the cavity 3a can be further enhanced.

  Thereafter, vacuum pressure bonding shown in step S3 of FIG. 4 is performed. That is, here, the minute movable sensor 2d is hermetically sealed in a vacuum state. That is, in a state where evacuation is performed, the boss 4a on the semiconductor wafer 8 and the concave portion 3b of the cap member 3 are fitted by caulking as shown in the crimping bonding in step S4, and the semiconductor wafer 8 and the cap are fitted. The member 3 is joined, and thereby the minute movable sensor 2d is covered with the cavity 3a, and the minute movable sensor 2d is hermetically sealed in a vacuum state. At that time, the boss 4a made of soft metal is plastically deformed along the groove of the recess 3b by the stress at the time of pressure bonding and is fitted into the recess 3b.

  As a result, the boss 4a and the recess 3b can be connected by a connection of fitting by metal caulking, and the mechanical strength can be maintained.

  Further, by covering the minute movable sensor 2d with the cavity portion 3a while the vacuum is being evacuated, the minute movable sensor 2d can be hermetically sealed with the inside of the cavity portion 3a being in a vacuum state.

  The pressure bonding in step S4 may be performed not only in a vacuum state but also in an inert gas atmosphere as necessary. In that case, the inside of the cavity portion 3a is set as an inert gas atmosphere and the MEMS such as the micro movable sensor 2d is used. The element can be hermetically sealed.

  Further, by applying heat at the time of pressure bonding in Step S4, the melting point of the soft metal boss 4a is lowered and the hardness is lowered, so that the boss 4a is easily deformed, and caulking can be performed smoothly. However, it is not always necessary to apply heat.

  Thereafter, dicing shown in step S5 of FIG. 6 is performed. That is, the semiconductor wafer 8 shown in FIG. 4 is cut along each chip region 8b to obtain a plurality of semiconductor chips 2 each having a minute movable sensor 2d hermetically sealed.

  Thereafter, die bonding shown in step S6 of FIG. 6 is performed. Here, the semiconductor chip 2 is mounted on the package substrate 1.

  Thereafter, wire bonding shown in step S7 of FIG. 7 is performed. Here, the pads (electrodes) 2 b on the main surface 2 a of the semiconductor chip 2 and the electrodes connected to the through-hole wiring 1 a of the package substrate 1 are electrically connected by the wires 5.

  Thereafter, the sealing shown in Step S8 of FIG. 7 is performed. Here, the entire package is sealed by covering the semiconductor chip 2 and the plurality of wires 5 with a cap 6 or the like. However, the entire package covering the semiconductor chip 2 and the plurality of wires 5 may be sealed by resin sealing using a sealing resin.

  Thereafter, bump formation shown in step S9 of FIG. 8 is performed. Here, bump electrodes 7 serving as external terminals are connected to the back surface of the package substrate 1. The bump electrode 7 is, for example, a solder bump and is provided so as to be electrically connected to the wire 5 via the through-hole wiring 1a.

  Thereby, the assembly of the semiconductor device 12 of the first embodiment is completed.

  According to the semiconductor device and the manufacturing method thereof in the first embodiment, the boss 4a made of soft metal is formed on the semiconductor wafer 8 having the semiconductor chip 2 on which the minute movable sensor 2d is formed. The recess 3b formed in the cap member 3 that hermetically seals the movable sensor 2d is fitted by caulking, and the minute movable sensor 2d is hermetically sealed in a vacuum state (or inert gas atmosphere). Since the micro movable sensor 2d is hermetically sealed using a semiconductor process without using a simple assembly process, the micro movable sensor 2d can be hermetically sealed at a reduced cost.

  Therefore, the cost of the semiconductor device 12 in which the minute movable sensor 2d is hermetically sealed can be reduced.

  Further, the cap member 3 is not limited to silicon, and glass, plastic, or metal can be used, and there is no material restriction. Therefore, the cost can be reduced by selecting a cheap material. it can.

  Furthermore, since the micro movable sensor 2d is hermetically sealed using a normal semiconductor process, it is possible to assemble without requiring a large facility, and the cost of the semiconductor device 12 can be reduced.

  In addition, since the minute movable sensor 2d is hermetically sealed using a normal semiconductor process, it is possible to prevent deterioration of the element without applying a high voltage in a high temperature state. Thereby, the reliability of the semiconductor device 12 can be improved.

  Further, since the micro movable sensor 2d is hermetically sealed without performing plasma processing or the like, the manufacturing tolerance for the flatness and cleanliness of the surface of the material is increased, and the reliability of the semiconductor device 12 can be improved. .

  Further, since the cap member 3 is fitted and hermetically sealed on the semiconductor wafer 8 by caulking, a joint structure with excellent mechanical strength can be realized. Thereby, the reliability of the semiconductor device 12 can be improved.

  In addition, the micro movable sensor 2d is hermetically sealed using a normal semiconductor process, and the assembly process to be applied is not limited. Therefore, the assembly process of the semiconductor device 12 can be simplified.

  In the manufacture of the semiconductor device according to the first embodiment, a boss is formed by wafer processing in a gold bump forming step of a general semiconductor process, and is combined with a cap member 3 that is separately formed to form a final package (semiconductor device 12). Can be assembled without the need for special manufacturing techniques. That is, in the manufacture of the semiconductor device according to the first embodiment, airtight sealing of the minute movable sensor 2d, which is a MEMS sensor, can be realized by employing a semiconductor process and caulking with a metal.

(Embodiment 2)
FIG. 9 is a plan view showing an example of a structure after hermetic sealing in assembling the semiconductor device according to the second embodiment of the present invention through the cap member, and FIG. 10 is cut along the line AA shown in FIG. FIG. 11 is an enlarged partial cross-sectional view showing an example of the structure of part B shown in FIG.

  The semiconductor device according to the second embodiment has substantially the same structure as the semiconductor device 12 according to the first embodiment. However, as shown in FIGS. 9 to 11, the semiconductor chip 2 (semiconductor wafer 8) and the cap member 3 are formed. The elastomer 10 that is an elastic member is fitted to the semiconductor chip 2 (semiconductor wafer 8) and the cap member 3 across the bonding surface 11, thereby the micro movable sensor 2d that is a MEMS sensor is in a vacuum state. It is hermetically sealed.

  The elastomer 10 is formed in a ring shape, for example, and is provided between the bosses 4a arranged in two rows. At that time, the semiconductor chip 2 (semiconductor wafer 8) and the cap member 3 are fitted over the joining surface 11 of the semiconductor chip 2 (semiconductor wafer 8) and the cap member 3 in a state of surrounding the minute movable sensor 2d. ing.

  Thereby, the airtightness inside the cavity part 3a can further be improved.

  The elastic member is not limited to the elastomer 10 and may be a liquid or paste elastic member.

  Since the other structure and manufacturing method of the semiconductor device of the second embodiment and the operational effects obtained by these are the same as those of the first embodiment, a duplicate description thereof will be omitted.

(Embodiment 3)
FIG. 12 is a plan view showing an example of a structure after hermetic sealing in assembling the semiconductor device according to the third embodiment of the present invention through the cap member, and FIG. 13 is cut along the line AA shown in FIG. FIG. 14 is an enlarged partial cross-sectional view showing an example of the structure of the portion B shown in FIG.

  The semiconductor device according to the third embodiment shown in FIG. 12 has substantially the same structure as the semiconductor device 12 according to the first embodiment. However, as shown in FIGS. 13 and 14, the bottom of the recess 3b of the cap member 3 is formed. The alloyed metal 13 is deposited.

  Thereby, at the time of pressure bonding, the alloying metal 13 and the boss 4a undergo an alloying reaction, whereby the bonding force between the boss 4a and the recess 3b is increased, and the airtightness inside the cavity 3a can be further increased. .

  Note that the minute movable sensor 2d, which is a MEMS sensor, is hermetically sealed in a vacuum state, like the semiconductor device 12 of the first embodiment.

  Since the other structure and manufacturing method of the semiconductor device of the third embodiment and the operational effects obtained by these are the same as those of the first embodiment, the duplicate description thereof is omitted.

(Embodiment 4)
15 is a plan view showing an example of a structure after hermetic sealing in assembling the semiconductor device according to the fourth embodiment of the present invention through a cap member, and FIG. 16 is cut along the line AA shown in FIG. It is sectional drawing which shows the structure which carried out.

  The semiconductor device according to the fourth embodiment shown in FIG. 15 has substantially the same structure as the semiconductor device 12 according to the first embodiment. However, as shown in FIG. 16, the boss 4a is attached to the cap member when the semiconductor device is assembled. 3, and a recess 8 c is formed on the semiconductor wafer 8 side, whereby the boss 4 a on the cap member 3 side is fitted into the recess 8 c on the semiconductor wafer 8 side during pressure bonding. Thus, the cap member 3 is joined to the semiconductor wafer 8.

  Even in this case, the same effects as those of the first embodiment can be obtained.

  Note that the minute movable sensor 2d, which is a MEMS sensor, is hermetically sealed in a vacuum state, like the semiconductor device 12 of the first embodiment.

  Since the other structure and manufacturing method of the semiconductor device of the fourth embodiment are the same as those of the first embodiment, the duplicate description thereof is omitted.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiments of the invention. However, the present invention is not limited to the embodiments of the invention, and various modifications can be made without departing from the scope of the invention. It goes without saying that it is possible.

  For example, in the first embodiment, in the manufacturing of the semiconductor device, the case where the cap member 3 is joined (airtightly sealed) in a wafer state and then separated into pieces by dicing is described. In manufacturing the device, before the hermetically sealing with the cap member 3, first, the semiconductor wafer 8 is diced into individual pieces, and further bonded (hermetic sealing) to the cap member 3 for each chip. After that, assembly after hermetic sealing may be performed.

  The present invention is suitable for an electronic device having a MEMS element.

It is sectional drawing which shows an example of the structure of the semiconductor device of Embodiment 1 of this invention. It is a top view which permeate | transmits and shows an example of the structure after airtight sealing in the assembly of the semiconductor device shown in FIG. It is sectional drawing which shows the structure cut | disconnected along the AA line shown in FIG. FIG. 2 is a process flow diagram illustrating an example of a structure from sensor formation to cap member bonding in the assembly of the semiconductor device illustrated in FIG. 1. FIG. 2 is a process flow diagram illustrating an example of a structure up to cap member formation in the assembly of the semiconductor device illustrated in FIG. 1. FIG. 2 is a process flow diagram showing an example of a structure in a dicing and die bonding process in assembling the semiconductor device shown in FIG. 1. It is a process flow figure showing an example of the structure in the wire bonding and sealing process in the assembly of the semiconductor device shown in FIG. It is sectional drawing which shows an example of the structure after bump formation in the assembly of the semiconductor device shown in FIG. It is a top view which permeate | transmits and shows an example of the structure after airtight sealing in the assembly of the semiconductor device of Embodiment 2 of this invention. It is sectional drawing which shows the structure cut | disconnected along the AA line shown in FIG. It is an expanded partial sectional view which expands and shows an example of the structure of the B section shown in FIG. It is a top view which permeate | transmits and shows an example of the structure after airtight sealing in the assembly of the semiconductor device of Embodiment 3 of this invention. It is sectional drawing which shows the structure cut | disconnected along the AA line shown in FIG. It is an expanded partial sectional view which expands and shows an example of the structure of the B section shown in FIG. It is a top view which permeate | transmits and shows an example of the structure after airtight sealing in the assembly of the semiconductor device of Embodiment 4 of this invention. It is sectional drawing which shows the structure cut | disconnected along the AA shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Package substrate 1a Through-hole wiring 2 Semiconductor chip 2a Main surface 2b Pad (electrode)
2c Internal wiring 2d Micro movable sensor (micro movable element)
3 Cap member 3a Cavity 3b Recess 4a Boss (projection)
4b Adhesive layer 5 Wire 6 Cap 7 Bump electrode (external terminal)
8 Semiconductor wafer 8a Main surface 8b Chip area 8c Recess 9 Wafer for cap (thin plate member)
10 Elastomer (elastic member)
11 Bonding surface 12 Semiconductor device 13 Alloyed metal

Claims (5)

A semiconductor chip on which a minute movable element is formed;
A cap member mounted on the semiconductor chip and provided with a cavity portion, covering the minute movable element by the cavity portion and hermetically sealing the minute movable element;
A plurality of external terminals electrically connected to the electrodes of the semiconductor chip;
Of the semiconductor chip and the cap member, a soft metal projection formed on one of the semiconductor chip and a recess formed on the other is fitted by caulking so that the semiconductor chip and the cap member are A semiconductor device, wherein the micro movable elements are bonded and hermetically sealed in a vacuum state or in an inert gas atmosphere. A semiconductor chip on which a micro movable sensor having a beam structure is formed;
A cap member mounted on the semiconductor chip and provided with a cavity portion, covering the minute movable sensor with the cavity portion and hermetically sealing the minute movable sensor;
A plurality of external terminals electrically connected to the electrodes of the semiconductor chip;
Of the semiconductor chip and the cap member, a soft metal protrusion formed on one of the semiconductor chip and a wedge-shaped recess formed on the other is fitted by caulking to form the semiconductor chip and the cap. A semiconductor device, wherein a member is joined, and the minute movable sensor is hermetically sealed in a vacuum state or an inert gas atmosphere. A semiconductor chip on which a micro movable sensor having a beam structure is formed;
A cap member mounted on the semiconductor chip and provided with a cavity portion, covering the minute movable sensor with the cavity portion and hermetically sealing the minute movable sensor;
A plurality of external terminals electrically connected to the electrodes of the semiconductor chip;
Of the semiconductor chip and the cap member, a soft metal protrusion formed on one of the semiconductor chip and a recess formed on the other is fitted by caulking so that the semiconductor chip and the cap member are Further, an elastic member is fitted to the semiconductor chip and the cap member across the bonding surface of the semiconductor chip and the cap member, and the micro movable sensor is in a vacuum state or in an inert gas atmosphere. A semiconductor device which is hermetically sealed. (A) preparing a semiconductor chip on which a micro movable element is formed;
(B) preparing a cap member in which the cavity portion is formed;
(C) A soft metal protrusion formed on one of the semiconductor chip and the cap member and a recess formed on the other are fitted together by caulking to form the semiconductor chip and the cap. A method of manufacturing a semiconductor device, comprising: joining a member, covering the minute movable element with the cavity portion, and hermetically sealing the minute movable element in a vacuum state or an inert gas atmosphere. (A) forming a micro movable sensor having a beam structure on the plurality of chip regions of a semiconductor wafer having a plurality of chip regions on a main surface;
(B) On the main surface of the semiconductor wafer, a step of forming a protrusion made of a soft metal and projecting from the main surface around each micro movable sensor;
(C) forming a cap member by forming a plurality of cavities and recesses surrounding the cavities in a thin plate member made of silicon;
(D) The protruding portion of the semiconductor wafer and the concave portion of the cap member are fitted together by caulking to join the semiconductor wafer and the cap member, and the minute movable sensor is covered by the cavity portion to cover the minute movable sensor. Hermetically sealing the sensor in a vacuum or inert gas atmosphere;
(E) cutting the semiconductor wafer along each chip region, and obtaining a plurality of semiconductor chips each having the micro movable sensor hermetically sealed therein.

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