JP2006226777A - Manufacturing method of mechanical quantity sensor, mechanical quantity sensor and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing mechanical quantity sensor using an anode welding technique without damaging electric wiring, without breaking the insulation, and also without melting the wiring with preferable welding strength. <P>SOLUTION: The manufacturing method comprises: the through hole forming process for forming through holes 40 on the 1st glass substrate 20a; the 1st anode welding process for anode welding the 1st glass substrate 20a and the silicon substrate 21; the detector section forming process for forming the detector section and the columnar part 33 and 34 by etching the silicone substrate 21 which is welded with the 1st glass substrate 20a; the conductive film formation process for forming the conductive film 37 connected with the columnar part 33 and 34 from inside of the through hole 40 on the reverse side of welded surface of the silicon substrate 21 on the 1st glass substrate; and the 2nd anode welding process for anode welding the 2nd glass substrate 20b with the silicon substrate 21. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides a dynamic chamber represented by an acceleration sensor and an angular velocity sensor in which a sealed chamber is formed using a glass substrate and a silicon substrate, and a detection unit for detecting various mechanical quantities such as acceleration and angular velocity is housed in the sealed chamber. The present invention relates to a manufacturing method of a quantity sensor, a mechanical quantity sensor manufactured using the manufacturing method, and an electronic apparatus having the mechanical quantity sensor.

  Conventionally, in detecting acceleration or angular velocity applied to an electronic device, a mechanical quantity sensor in which a pair of glass substrates are bonded so as to sandwich a silicon substrate is provided. This type of mechanical quantity sensor forms a sealed chamber by using a glass substrate and a silicon substrate, and houses a detection unit for detecting various mechanical quantities such as acceleration and angular velocity in the sealed chamber.

  By the way, in joining the glass substrate to the upper and lower surfaces of the silicon substrate, an anodic bonding method is generally widely used. That is, the glass substrate is bonded to each one side of the upper and lower surfaces of the silicon substrate by using the anodic bonding method. At this time, when the first glass substrate is anodically bonded to the silicon substrate, they can be anodically bonded to each other without any problem.

However, when trying to anodically bond the second glass substrate to the silicon substrate to which the first glass substrate is bonded, the first glass substrate that has been previously anodically bonded to the silicon substrate is an electrically insulating material. The applied voltage had to be high, and the silicon substrate and the second glass substrate had to be at a high temperature. Specifically, the applied voltage had to be applied as high as several thousand volts, and the heating temperature had to be heated to a high temperature of 300-500 ° C.
JP 2001-158672 A

  However, as described above, when the second glass substrate is to be anodically bonded to the silicon substrate, a problem is caused by applying a high voltage to the glass substrate or the silicon substrate or heating to a high temperature. It was. That is, when a high voltage is applied to a glass substrate or silicon substrate, there is a problem that the electric wiring provided on the glass substrate or silicon substrate is damaged or that the insulating portion is destroyed. It was. In addition, when a glass substrate or a silicon substrate is heated to a high temperature, a metal having a low melting point such as aluminum or copper used for electrical wiring may melt, and there is a demand for setting the heating temperature low. .

  The present invention has been made in view of such circumstances, and its purpose is a method of manufacturing a mechanical quantity sensor using the anodic bonding method as described above, without damaging the electrical wiring, It is another object of the present invention to provide a method for manufacturing a mechanical quantity sensor that does not destroy an insulating portion, further prevents electric wiring from being melted, and has favorable bonding strength.

The present invention provides the following means in order to solve the above problems.
The method of manufacturing a mechanical quantity sensor according to the present invention is a method of manufacturing a mechanical quantity sensor configured by sandwiching a silicon substrate between a first glass substrate and a second glass substrate, and a through hole provided with a through hole in the first glass substrate. A hole forming step, a first anodic bonding step for anodically bonding the first glass substrate provided with the through hole and the silicon substrate, and a conductive material electrically connected to the silicon substrate through the through hole. A conductive film forming step of providing a film on the surface of the first glass substrate opposite to the surface on which the silicon substrate is bonded; a second anodic bonding step of anodic bonding the second glass substrate and the silicon substrate; It is provided with.

  The method for manufacturing a mechanical quantity sensor of the present invention includes a through-hole forming step, a first anodic bonding step, a conductive film forming step, and a second anodic bonding step. In the conductive film forming step, a conductive film is provided over the surface of the first glass substrate opposite to the surface to which the silicon substrate is bonded. The conductive film is electrically connected to the silicon substrate through the through hole provided in the first glass substrate in the through hole forming step. Accordingly, when a voltage is applied to the conductive film through the conductive plate while a glass substrate is interposed between the conductive plate and the silicon substrate, the conductive film is energized to the silicon substrate. A voltage is applied.

  As a result, in the second anodic bonding step of anodic bonding the second glass substrate and the silicon substrate, a voltage can be suitably applied to the silicon substrate in the same manner as the anodic bonding of the first glass substrate and the silicon substrate. Become. Therefore, the second glass substrate and the silicon substrate are preferably anodically bonded. In other words, it is possible to energize the silicon substrate through the through-hole provided in the glass substrate while being in the state of being through the insulating glass substrate, so that a high voltage as in the conventional case is applied. It is not necessary to apply it, and the temperature at which the glass substrate is heated in order to cause thermal diffusion of alkali metal ions can be selected from about 200 to 400 ° C. as usual.

  Specifically, it is not necessary to apply a voltage of several thousand volts, which damages the electrical wiring or destroys the insulating part, and a normal voltage of 200 to 600 V is applied. It will be good. Moreover, at the time of this joining, the heating temperature can select 200-400 degreeC as usual. Therefore, the second glass substrate and the silicon substrate are preferably anodically bonded.

  Moreover, in this manufacturing method, the detection part formation process which etches so that a detection part and the columnar part distribute | arranged around this detection part may be formed in the said silicon substrate joined to the said 1st glass substrate. May be included. When this detection part formation process is included, the location where the conductive film is electrically connected in the conductive film formation process is a columnar part of the silicon substrate. In addition, this columnar part is a columnar part which supports each other of a pair of glass substrate among this silicon substrate.

  When the detection part forming step is provided in this way, the conductive film passes through the columnar part provided by etching the silicon substrate and the through hole provided in the first glass substrate in the through hole forming step. Electrically connected. Therefore, as described above, when a voltage is applied to the conductive film through the conductive plate even though the glass substrate is interposed between the conductive plate and the silicon substrate, the pair of first electrodes A voltage is applied to the columnar portions that support the first glass substrate and the second glass substrate. Thus, in the second anodic bonding step of anodic bonding the second glass substrate and the silicon substrate, a voltage is suitably applied to the columnar portion of the silicon substrate, similarly to the anodic bonding of the first glass substrate and the silicon substrate. Application is possible. Therefore, the second glass substrate and the columnar portion of the silicon substrate are preferably anodically bonded.

  Furthermore, in the manufacturing method of the mechanical quantity sensor of the invention described above, a terminal forming step of dividing the conductive film and providing an independent terminal for each of the through holes may be included. When this terminal formation step is included in the above-described method for manufacturing a mechanical quantity sensor, a terminal capable of electrical connection is provided by dividing the conductive film provided in the conductive film formation step. Therefore, since a terminal is provided using this conductive film, a formation process for newly providing a terminal can be omitted. As a result, the workability of the manufacturing is improved, leading to a reduction in manufacturing time and a reduction in manufacturing cost.

  The manufacturing method of a mechanical quantity sensor of the present invention is a manufacturing method of a mechanical quantity sensor configured by sandwiching a silicon substrate between a first glass substrate and a second glass substrate, and a through hole is formed in the first glass substrate. A through hole forming step to be provided; a first anodic bonding step for anodically bonding the first glass substrate provided with the through hole and the silicon substrate; and the silicon substrate through the through hole. A conductive material burying step of burying the conductive material in the through-hole, and a second anodic bonding step of anodic bonding the second glass substrate and the silicon substrate.

  The method for manufacturing a mechanical quantity sensor of the present invention includes a through-hole forming step, a first anodic bonding step, a conductor embedding step, and a second anodic bonding step. In the conductor embedding step, the conductor is embedded in the through hole provided in the first glass substrate in the through hole forming step. The conductor provided in the through hole is electrically connected to the silicon substrate. Accordingly, when a glass substrate is interposed between the conductive plate and the silicon substrate, and a voltage is applied to the conductor via the conductive plate, the conductive substrate is energized to pass through the silicon substrate. A voltage is applied to.

  As a result, in the second anodic bonding step of anodic bonding the second glass substrate and the silicon substrate, a voltage can be suitably applied to the silicon substrate in the same manner as the anodic bonding of the first glass substrate and the silicon substrate. Become. Therefore, the second glass substrate and the silicon substrate are preferably anodically bonded. In other words, it is possible to energize the silicon substrate through the through-hole provided in the glass substrate while being in the state of being through the insulating glass substrate, so that a high voltage as in the conventional case is applied. It is not necessary to apply it, and the temperature at which the glass substrate is heated in order to cause thermal diffusion of alkali metal ions can be selected from about 200 to 400 ° C. as usual.

  Specifically, it is not necessary to apply a voltage of several thousand volts, which damages the electrical wiring or destroys the insulating part, and a normal voltage of 200 to 600 V is applied. It will be good. Moreover, at the time of this joining, the heating temperature can select 200-400 degreeC as usual. Therefore, the second glass substrate and the silicon substrate are preferably anodically bonded.

  Moreover, in this manufacturing method, the detection part formation process which etches so that a detection part and the columnar part distribute | arranged around this detection part may be formed in the said silicon substrate joined to the said 1st glass substrate. May be included. When this detection part formation process is included, the part where the conductor is electrically connected in the conductor embedding process is a columnar part of the silicon substrate. In addition, this columnar part is a columnar part which supports each other of a pair of glass substrate among this silicon substrate.

  When the detection part forming step is thus provided, the conductor passes through the columnar part provided by etching the silicon substrate and the through hole provided in the first glass substrate in the through hole forming step. Electrically connected. Therefore, as described above, when a voltage is applied to the conductor via the conductive plate while the glass substrate is interposed between the conductive plate and the silicon substrate, the pair of second electrodes A voltage is applied to the columnar portions that support the first glass substrate and the second glass substrate. Thus, in the second anodic bonding step of anodic bonding the second glass substrate and the silicon substrate, a voltage is suitably applied to the columnar portion of the silicon substrate, similarly to the anodic bonding of the first glass substrate and the silicon substrate. Application is possible. Therefore, the second glass substrate and the columnar portion of the silicon substrate are preferably anodically bonded. In addition, after the second glass substrate and the silicon substrate are suitably anodically bonded, the conductor provided in the through hole can be used as a terminal, so that a forming step for newly providing a terminal can be omitted. As a result, manufacturing workability is improved.

  In the method of manufacturing a mechanical quantity sensor according to the present invention, the positions where the through holes are provided are the respective positions in contact with the columnar portion of the first glass substrate.

  In the manufacturing method of the mechanical quantity sensor of the present invention, since the through hole is provided at each position in contact with the columnar portion of the first glass substrate, the conductive film or conductor provided in the through hole. Are suitably connected to each of the columnar parts provided by etching the silicon substrate in the detection part forming step. As a result, even when the columnar portion of the silicon substrate is not in contact with other columnar portions, a voltage is suitably applied to each of the independent columnar portions. Each is suitably anodically bonded to the second glass substrate.

  Therefore, the sealed chamber is suitably configured by the first glass substrate, the second glass substrate, and the silicon substrate sandwiched between these glass substrates. Therefore, a detection unit that detects various mechanical quantities such as acceleration and angular velocity can be suitably accommodated in the sealed chamber. Accordingly, it can be suitably used as a mechanical quantity sensor such as an acceleration sensor or an angular velocity sensor.

  In addition, when an electronic device is configured using a mechanical quantity sensor manufactured using the above-described mechanical quantity sensor manufacturing method, the applied voltage is changed from several thousand volts to damage the electrical wiring or destroy the insulation part. It is possible to select a normal voltage of 200 to 600 V that makes it difficult to cause the heating to occur, and it is also possible to select a normal heating temperature of 200 to 400 ° C. Therefore, when anodically bonding the second glass substrate and the silicon substrate, an electronic device is configured with a mechanical quantity sensor that is avoided from problems such as damage to the electrical wiring or melting or destruction of the insulation portion. . In this way, an electronic device whose mechanical quantity can be suitably detected is obtained.

  According to the manufacturing method of the mechanical quantity sensor according to the present invention, the applied voltage is reduced to 200 to 600 V when the silicon substrate and the glass substrate are anodic bonded, although it is a manufacturing method of the mechanical quantity sensor using the anodic bonding method. Furthermore, the heating temperature at the time of joining can also select 200-300 degreeC. As a result, the conventional problems such as damage to the electrical wiring, destruction of the insulating portion, melting of the metal constituting the electrical wiring and the like have been solved, and the bonding strength between the silicon substrate and the glass substrate has been made favorable. A mechanical quantity sensor can be obtained.

  DESCRIPTION OF EMBODIMENTS Embodiments relating to an electronic device in which a mechanical quantity sensor according to the present invention is incorporated, a mechanical quantity sensor thereof, and a manufacturing method of the mechanical quantity sensor will be described below with reference to the drawings. In this embodiment, the electronic device is described as an electronic device 1 having a camera mechanism such as a digital camera or a mobile phone, and the mechanical quantity sensor is described as a gyro sensor 2 that detects angular velocity. .

  Reference numeral 1 shown in FIG. 1 is an electronic apparatus having a camera mechanism such as a digital camera or a mobile phone, and includes a camera module 3 and a sensor unit 4 having the gyro sensor 2. The camera module 3 includes a lens correction amount calculation circuit 5 that calculates a correction amount of a camera lens (not shown) based on the angular velocity sent from the sensor unit 4, and a correction amount calculated by the lens correction amount calculation circuit 5. And a lens driving circuit 8 for driving the X-axis lens actuator 6 and the Y-axis lens actuator 7. The lens actuators 6 and 7 can perform camera shake correction and the like by displacing the camera lens in the X and Y directions as appropriate.

  The sensor unit 4 includes the gyro sensor 2, a CV conversion circuit 9 that converts a capacitance according to the angular velocity detected by the gyro sensor 2 into a voltage, and an angular velocity that calculates an angular velocity from the converted voltage. And a calculation circuit 10. Further, the angular velocity calculation circuit 10 outputs the calculated angular velocity to the lens correction amount calculation circuit 5.

As shown in FIGS. 2A and 2B, the gyro sensor 2 is sandwiched between a pair of glass substrates 20 (20a, 20b) and the pair of glass substrates 20 (20a, 20b). A silicon substrate 21 bonded by anodic bonding in a state, a sealed chamber 22 surrounded by the silicon substrate 21 and a pair of glass substrates 20, and an angular velocity (mechanical quantity) accommodated in the sealed chamber 22 and acting from the outside. And a detecting unit 23 for detecting. In the present embodiment, as the silicon substrate 21, a silicon (Si) support substrate 25 (for example, a thickness of 300 to 800 μm) and a silicon dioxide (SiO ₂ ) BOX layer formed on the Si support substrate 25. An SOI (Silicon On Insulator) substrate (hereinafter simply referred to as a silicon substrate) 21 having a (Buried Oxide) 26 and a Si active layer 27 (for example, a thickness of 5 to 100 μm) formed on the BOX layer 26 was used. An example will be described.

  The sealed chamber 22 is formed by a space surrounded by a recess 30 formed in the silicon substrate 21 and the pair of glass substrates 20. Further, as shown in FIGS. 2A and 2B, the silicon substrate 21 does not contact the glass substrate 20 (20a, 20b) by the four beams (beam portions) 31 in the sealed chamber 22. Thus, a proof mass 32 suspended (in a hollow state) is formed. The four beams 31 are supported on the base end side by a frame 33 (33a, 33b) surrounded by a quadrangular shape, and extend inward from intermediate positions of the four sides of the frame 33, respectively. Has been. Further, as shown in FIG. 2A, posts 34 (34a, 34b) are provided between the pair of glass substrates 20 (20a, 20b) at a predetermined interval around the frame 33. Yes. The frame 33 (33a, 33b) and the post 34 (34a, 34b) correspond to the columnar portion of the silicon substrate 21 in the present invention.

  A first electrode 35 a is provided on the glass substrate 20 (first glass substrate 20 a) on the Si active layer 27 side and at a position facing the proof mass 32. The first electrode 35a is electrically connected to a first electrode pad 36a and a fourth electrode pad 36b provided between the first glass substrate 20a and the frame 33 by wiring not shown. When a voltage is applied to the first electrode pad 36a, an electrostatic attractive force acts on the upper portion of the proof mass 32 from the first electrode 35a.

  A second electrode 35b is provided on the glass substrate 20 (second glass substrate 20b) on the Si support substrate 25 side at a position facing the proof mass 32. The second electrode 35b is connected through a third electrode pad 36c, a first post 34a, and a wiring 38a provided between the second glass substrate 20b and the first post 34a, and also connected to the wiring 38b and the first post 34a. It is electrically connected to the fourth electrode pad 36d through the two posts 34b. When a voltage is applied to the third electrode pad 36c, an electrostatic attractive force acts on the lower portion of the proof mass 32 from the second electrode 35b.

  As shown in FIGS. 2A and 2B, the proof mass 32 is excited with a predetermined input waveform by electrostatic attraction by the first electrode 35a and the second electrode 35b. When the proof mass 32 receives an angular velocity from the outside in this excited state, the proof mass 32 is twisted and displaced about the four beams 31 around the X or Y direction. Here, on the glass substrate 20 on the Si active layer 27 side, a detection electrode (not shown) for measuring the distance from the proof mass 32 is provided at a position facing the proof mass 32. This detection electrode detects a change in distance from the proof mass 32 as a change in capacitance. As a result, the displacement of the proof mass 32 can be detected as an electrostatic capacity corresponding to the displacement, and the detected capacity is a second capacity provided between the first glass substrate 20a and the post 34 (34a, 34b). The signal is output to the CV conversion circuit 9 via the electrode pad 36b and the fourth electrode pad 36d. That is, the proof mass 32, the first electrode 35a, the second electrode 35b, and the detection electrode function as the detection unit 23 housed in the sealed chamber 22.

  The first glass substrate 20a is provided with four through holes 40 (40a, 40b, 40c, 40d) at predetermined intervals when the first to fourth electrode pads 36a, 36b, 36c, 36d described above are provided. Each of the first through fourth through holes 40a, 40b, 40c, and 40d is formed by forming an electrode pad. The first to fourth electrode pads 36a, 36b, 36c, 36d can be electrically connected to an external device. Further, the first to fourth electrode pads 36a, 36b, 36c, 36d are formed over the entire inner peripheral surface of the through hole 40 (40a, 40b, 40c, 40d). It is also formed over the periphery of the opening end. The first to fourth electrode pads 36a, 36b, 36c, 36d correspond to the terminals in the present invention, and are 33 (33a, 33b), 34 (34a) corresponding to the columnar portion of the silicon substrate 21. , 34b) while being electrically connected. Further, between the first to fourth electrode pads 36a, 36b, 36c, and 36d, a surface notch 60 (60a, 60a, 60d) is formed so that the surface 51 of the first glass substrate 20a is notched. 60b, 60c).

  Next, a manufacturing method for manufacturing the gyro sensor 2 will be described with reference to FIGS. In the embodiment of the method for manufacturing the gyro sensor 2 to be described below, the present invention and the silicon substrate as the main part are provided as means for solving the above-described problems. The gyro sensors 2a and 2b, which will be described below with reference to the glass substrate, are simplified from the gyro sensor 2 described above. That is, of the silicon substrate 21 described above, the silicon support substrate 25, the BOX layer 26, and the Si active layer 27 are not illustrated separately, and the first electrode 35a and the second electrode Illustration of the electrode 35b is also omitted. In addition, these are formed in the detection part formation process in the manufacturing process of this gyro sensor 2 demonstrated later.

  Furthermore, although the electrode pad 36 of the gyro sensor 2 described above is configured as four, the electrode pad 36 of the gyro sensor 2 (2a, 2b) described below is It is simplified and configured as three. And even if it exists in the flame | frame 33 and the post 34 which correspond to the columnar part used as the columnar site | part which supports each other of this pair of glass substrate 20a, 20b among the silicon substrates 21 mentioned above, the above-mentioned gyro sensor 2 is simplified. It has become. As will be described in detail later, the frame 33 and the post 34 are formed into a space between each other and are anodically bonded to the pair of glass substrates 20a and 20b as shown in FIG. Further, in the embodiment of the manufacturing method of the gyro sensor 2 described below, each process may include an appropriate process, and a new process is included between the processes. It may be. In the first and second embodiments described below, an example will be described in which a silicon substrate is provided with a frame 33 and posts 34 that are columnar portions by etching the silicon substrate.

[First Embodiment]
That is, the reference numeral 2a (2) shown in FIG. 3 is configured by anodically bonding the silicon substrate 21 between the first glass substrate 20a and the second glass substrate 20b, which are a pair of glass substrates 20. 1 schematically shows a gyro sensor. The gyro sensor 2a is manufactured through the steps illustrated in FIGS. 4 (a) to 4 (f). That is, in the manufacture of the gyro sensor 2a, the through-hole forming step, the first anodic bonding step, the detecting portion forming step, the conductive film forming step, the second anodic bonding step, and the terminal forming step are performed. Contains.

  First, in the through hole forming step, as shown in FIG. 4A, through holes 40 (40a, 40b, 40c) are provided in the first glass substrate 20a. The through holes 40 (40a, 40b, 40c) are columnar portions provided in the silicon substrate 21 in the detection portion forming step (FIG. 4C) described in detail later in the first glass substrate 20a. Each of the portions in contact with the frame 33 and the post 34 is provided by processing such as sandblasting.

  Specifically, in the first glass substrate 20a, the portion in contact with the frame 33 and the post 34, which are columnar portions provided on the silicon substrate 21 in the subsequent detection portion forming step (FIG. 4C). Only a masking sheet with holes patterned is produced. Then, the masking sheet is attached to one surface (the upper surface in the figure) of the first glass substrate 20a, and compressed air mixed with sand for polishing such as gold sand is sprayed on the one surface to which the masking sheet is attached, and masking is performed. Excavate where the sheet is not protected. In this manner, the through hole 40 (40a, 40b, 40c) is provided by excavating from one surface of the first glass substrate 20a to the other surface (the lower surface in the drawing). Such physical excavation is not limited to sand blasting, and may be excavation performed by blowing high-pressure water, for example. And after the through-hole 40 is provided in the said 1st glass substrate 20a, the masking sheet attached to the said 1st glass substrate 20a is removed, and this 1st glass substrate 20a is wash | cleaned. Further, when the through-hole 40 is provided by such physical excavation, the through-hole is generally shrunk toward the other surface of the first glass substrate 20a as shown in FIG. It is configured to be calibrated. The excavation for providing the through-holes 40 (40a, 40b, 40c) is not limited to the physical excavation such as the above-described sandblasting, and any chemical excavation by a known etching process or the like may be used. No problem.

  And after this through-hole formation process, it moves to a 1st anodic bonding process. In the first anodic bonding step, as shown in FIG. 4B, the first glass substrate 20a provided with the through holes 40 (40a, 40b, 40c) as described above is anodic bonded to the silicon substrate 21. The Specifically, the other surface (lower surface in the drawing) of the first glass substrate 20a and one surface (upper surface in the drawing) of the silicon substrate 21 are brought into contact over the entire surface. Although not shown, a positive voltage is applied to the conductive plate that is in contact with the other surface of the silicon substrate 21 (the surface shown in the drawing), and one surface of the first glass substrate 20a (the upper surface in the drawing) is applied. A negative voltage is applied to the contacted conductive plate. Then, an electrostatic attractive force is generated between the silicon substrate 21 and the first glass substrate 20a, and the mutually contacted surfaces are chemically bonded. In this way, the first glass substrate 20a and the silicon substrate 21 are anodically bonded. In this anodic bonding, the first glass substrate 20a is heated to 200 to 400 ° C. by a heater built in a conductive plate in contact with one surface (the upper surface in the drawing) of the first glass substrate 20a. Has been. The applied voltage is 200 to 600V.

  Next, the process proceeds to the detection part forming step. In this detection part forming step, as shown in FIG. 4C, the silicon substrate 21 to which the first glass substrate 20a is bonded is placed on the other surface (in the drawing, opposite to the bonding surface). The detection unit 23, the frame (columnar portion) 33, and the post (columnar portion) 34 described above are provided by etching from the lower surface side. This etching process is not much different from the known etching process, and an appropriate resist film is formed on the silicon substrate so that the detection part 23, the frame (columnar part) 33, and the post (columnar part) 34 are formed. A film is formed on the other surface of the substrate 21, and then the other surface of the silicon substrate 21 is etched by an appropriate spray etching or the like. After the etching process, the formed resist film is removed and the removed surface is washed. In this way, a desired space is formed in the silicon substrate 21, whereby the detection part 23, the frame (columnar part) 33 and the post (columnar part) 34 are provided in the silicon substrate 21.

  After this detection part forming process, the process proceeds to a conductive film forming process for forming a conductive film on the first glass substrate 20a shown in FIG. In this conductive film forming step, the conductive film 37 having conductivity is the surface of the first glass substrate 20a opposite to the surface bonded to the silicon substrate 21, that is, one surface of the first glass substrate 20a ( A film is formed on the upper surface in FIG. The conductive film 37 is also formed over the inner peripheral surface of the through hole 40 (40a, 40b, 40c) and one surface of the silicon substrate 21 in the through hole 40 (40a, 40b, 40c). The conductive film 37 is electrically connected to the frame 33 and the post 34 constituting the columnar portion by the positions where these films are formed. That is, in other words, the conductive film 37 is formed over the entire surface on the one surface (the upper surface in the drawing) side of the first glass substrate 20a. In this film formation, an appropriate film formation method can be employed. For example, a conductive metal such as aluminum is formed by vapor deposition, or by a sputtering method or a CVD (Chemical Vapor Deposition) method. A film may be formed.

  After this conductive film forming step, the process proceeds to the second anodic bonding step. In this second anodic bonding step, as shown in FIG. 4E, the second glass substrate 20b is anodic bonded to the silicon substrate 21 that is anodic bonded to the first glass substrate 20a. Specifically, the first conductive plate 91 is disposed in contact with the conductive film 37 provided on the first glass substrate 20a, and on the other surface (the lower surface in the drawing) of the second glass substrate 20b. The second conductive plate 92 is disposed in contact with the second conductive plate 92. Then, one surface (the upper surface in the drawing) of the second glass substrate 20b and the other surface (the lower surface in the drawing) of the silicon substrate 21 are brought into contact over the entire surface. A positive voltage is applied to the first conductive plate 91 by the electrode 93 and a negative voltage is applied to the second conductive plate 92. The positive voltage applied to the first conductive plate 91 is energized to the silicon substrate 21 through the conductive film 37 provided on the first glass substrate 20a. Then, an electrostatic attractive force is generated between the silicon substrate 21 and the second glass substrate 20b, and the mutually contacted surfaces are chemically bonded. In this way, the second glass substrate 20b and the silicon substrate 21 are anodically bonded. During the anodic bonding, the second glass substrate 20b is heated to 200 to 400 ° C. by a heater built in the second conductive plate 92. The applied voltage is set to 200 to 600 V as in the case of anodic bonding of the first glass substrate 20a.

  Then, after the second anodic bonding process, the process proceeds to a terminal forming process. In this terminal forming step, as shown in FIG. 4 (f), the conductive film 37 is divided to form independent terminals for each portion where the through holes 40 (40a, 40b, 40c) are provided. To do. That is, the electrode pads 36 (36e, 36f, 36g) are formed so that the conductive film 37 becomes an independent terminal at each location where the through holes 40 (40a, 40b, 40c) are provided by etching or the like. Form. Specifically, each of the conductive film 37 where the through hole 40 (40a, 40b, 40c) is disposed has a diameter slightly larger than that of the through hole 40 (40a, 40b, 40c). A resist film is formed. Thereafter, the conductive film 37 is etched by appropriate spray etching or the like. After the etching process, the formed resist film is removed and the removed surface is washed. In this way, only the portions where the through holes 40 (40a, 40b, 40c) are arranged are left in the conductive film 37 provided on the first glass substrate 20a. In other words, among the conductive film 37, the conductive films other than the portions where the through holes 40 (40a, 40b, 40c) are disposed are removed by the etching process and are separated from each other. The remaining conductive film constitutes the electrode pad 36 (36e, 36f, 36g).

  By taking the above steps, the gyro sensor 2a (2) shown in FIG. 3 can be manufactured. The gyro sensor 2a (2) manufactured in this way has the following effects. That is, the conductive film 37 provided in the conductive film forming step is provided on the first glass substrate in the through-hole forming step, and the frame 33 and the post 34 that are columnar portions provided by etching the silicon substrate 21. It is electrically connected through the through hole 40 (40a, 40b, 40c). Accordingly, when a voltage is applied to the conductive film 37 via the first conductive plate 91 while the glass substrate 20a is interposed between the first conductive plate 91 and the silicon substrate 21, The applied voltage energizes the conductive film 37 and applies the voltage to the frame 33 and the post 34 that are the columnar portions of the silicon substrate 21.

  Thus, in the second anodic bonding step of anodic bonding the second glass substrate 20b and the silicon substrate 21, a voltage is applied to the silicon substrate 21 in the same manner as the anodic bonding of the first glass substrate 20a and the silicon substrate 21. It can be suitably applied. Therefore, the second glass substrate 20b and the silicon substrate 21 are preferably anodically bonded. That is, the silicon substrate 21 is energized through the through-holes 40 (40a, 40b, 40c) provided in the first glass substrate 20a while being in the state through the insulating first glass substrate 20a. Therefore, it is not necessary to apply a high voltage as in the prior art, and the temperature at which the glass substrate is heated to cause the thermal diffusion of alkali metal ions is 200 as usual. A temperature of about ˜400 ° C. can be selected.

  Specifically, it is not necessary to apply a voltage of several thousand volts, which damages the electrical wiring or destroys the insulating part, and a normal voltage of 200 to 600 V is applied. It will be good. Moreover, at the time of this joining, the heating temperature can select 200-400 degreeC as usual. Therefore, the second glass substrate 20b and the silicon substrate 21 are preferably anodically bonded.

  Furthermore, in this method of manufacturing a mechanical quantity sensor, since the conductive film 37 is divided, a terminal forming step is provided in which an independent terminal 36 is provided for each of the through holes 40 (40a, 40b, 40c). A terminal capable of electrical connection is provided using this conductive film. Therefore, the formation process for newly providing a terminal can be omitted. As a result, the workability of the manufacturing is improved, leading to a reduction in manufacturing time and a reduction in manufacturing cost.

  In addition, since the through holes 40 (40a, 40b, 40c) are provided in the respective portions of the first glass substrate 20a that are in contact with the frame 33 and the post 34 that are columnar portions, the through holes 40 (40a, 40b, The conductive film 37 provided in 40c) is suitably connected to each of the frame 33 and the post 34 which are columnar parts provided by etching the silicon substrate 21 in the detection part forming step. As a result, even when the frame 33 of the silicon substrate 21 is not in contact with the post 34, the voltages of the independent frame 33 and the post 34 are suitably applied. Each of the frame 33 and the post 34 is preferably anodically bonded to the second glass substrate 20b.

  Therefore, the sealed chamber is suitably configured by the first glass substrate 20a, the second glass substrate 20b, and the silicon substrate 21 sandwiched between these glass substrates. Therefore, the detection unit 23 for detecting various mechanical quantities such as acceleration and angular velocity can be suitably accommodated in the sealed chamber. Thus, it can be suitably used as a mechanical quantity sensor such as an acceleration sensor or an angular velocity sensor.

[Second Embodiment]
Next, a second embodiment different from the above-described first embodiment will be described. In the following description, the same reference numerals as those in the first embodiment described above are the same as those in the first embodiment described above. Reference numeral 2b (2) shown in FIG. 5 is a gyro sensor configured by anodically bonding the silicon substrate 21 between the first glass substrate 20a and the second glass substrate 20b, which are a pair of glass substrates 20. Is schematically shown. The gyro sensor 2b is manufactured through the steps illustrated in FIGS. 6 (a) to 6 (e). That is, in the manufacture of the gyro sensor 2b, a through hole forming step, a first anodic bonding step, a detecting portion forming step, a conductor embedding step, a second anodic bonding step, and a terminal forming step are performed. Contains.

  First, in the through hole forming step, as shown in FIG. 6A, through holes 40 (40a, 40b, 40c) are provided in the first glass substrate 20a. The through holes 40 (40a, 40b, 40c) are columnar portions provided in the silicon substrate 21 in the detection portion forming step (FIG. 6D), which will be described in detail later, in the first glass substrate 20a. Each of the portions in contact with the frame 33 and the post 34 is provided by a known etching process.

  Specifically, in the first glass substrate 20a, a portion that is in contact with the frame 33 and the post 34, which are columnar portions provided in the silicon substrate 21 in a later detection portion forming step (FIG. 6D), is formed. Except for this, a resist film is formed on one surface (the upper surface in the drawing) 20a of the first glass substrate. Then, one surface of the first glass substrate 20a is etched by appropriate spray etching or the like on the first glass substrate 20a on which the resist film is formed. After the etching process, the formed resist film is removed and the removed surface is washed. Thus, the first glass substrate 20a has through holes 40 (40a, 40b, 40c) penetrating from one surface (upper surface in the drawing) to the other surface (lower surface in the drawing) of the first glass substrate 20a. Provided. In this etching process, a resist film is formed on only one side and etched, but a resist film may be formed on both sides and etched.

  In addition, in providing the said through-hole 40 (40a, 40b, 40c), as demonstrated in 1st Embodiment, it is not limited to the chemical thing mentioned above, but physical excavation, such as sandblasting, is carried out. May be provided on the first glass substrate 20a.

  And after this through-hole formation process, it moves to a 1st anodic bonding process. In this first anodic bonding step, as shown in FIG. 6B, the first glass substrate 20a provided with the through holes 40 (40a, 40b, 40c) as described above is anodic bonded to the silicon substrate 21. The Specifically, the other surface (lower surface in the drawing) of the first glass substrate 20a and one surface (upper surface in the drawing) of the silicon substrate 21 are brought into contact over the entire surface. Although not shown, a positive voltage is applied to the conductive plate that is in contact with the other surface of the silicon substrate 21 (the surface shown in the drawing), and one surface of the first glass substrate 20a (the upper surface in the drawing) is applied. A negative voltage is applied to the contacted conductive plate. Then, an electrostatic attractive force is generated between the silicon substrate 21 and the first glass substrate 20a, and the mutually contacted surfaces are chemically bonded. In this way, the first glass substrate 20a and the silicon substrate 21 are anodically bonded. In this anodic bonding, the first glass substrate 20a is heated to 200 to 400 ° C. by a heater built in a conductive plate in contact with one surface (the upper surface in the drawing) of the first glass substrate 20a. Has been. The applied voltage is 200 to 600V.

  Next, the process proceeds to the detection part forming step. In this detection portion forming step, as shown in FIG. 6C, the silicon substrate 21 to which the first glass substrate 20a is bonded is placed on the other surface (in the drawing, opposite to the bonding surface). The detection unit 23, the frame (columnar portion) 33, and the post (columnar portion) 34 described above are provided by etching from the lower surface side. This etching process is not much different from the known etching process, and an appropriate resist film is formed on the silicon substrate so that the detection part 23, the frame (columnar part) 33, and the post (columnar part) 34 are formed. A film is formed on the other surface of the substrate 21, and then the other surface of the silicon substrate 21 is etched by an appropriate spray etching or the like. After the etching process, the formed resist film is removed and the removed surface is washed. In this way, a desired space is formed in the silicon substrate 21, whereby the detection part 23, the frame (columnar part) 33 and the post (columnar part) 34 are provided in the silicon substrate 21.

  After this detection portion forming step, as shown in FIG. 6 (d), a conductor embedded in which a conductor 37a is embedded in the through hole 40 (40a, 40b, 40c) provided in the first glass substrate 20a. Move on to the process. The conductor 37a is conductive and also serves as the electrode pad 36 (36h, 36i, 36j). Specifically, a molten conductive metal is poured into the through hole 40 (40a, 40b, 40c), or a solid metal is fitted into the through hole 40 (40a, 40b, 40c). And what is it. The conductor 37a is electrically connected to the frame 33 and the post 34 constituting the columnar portion, and is provided so as to be flush with or slightly protrude from one surface (the upper surface in the drawing) of the first glass substrate 20a. . Therefore, when a conductive metal chip is fitted into the through-hole 40 (40a, 40b, 40c), an electrical bonding material that fills the gap is injected so as to be preferably electrically connected to the silicon substrate 21. In addition, a conductor 37a is provided on one surface (the upper surface in the drawing) side of the first glass substrate 20a so that the metal chip protrudes slightly.

  After this conductor embedding process, the process proceeds to the second anodic bonding process. In the second anodic bonding step, as shown in FIG. 6E, the second glass substrate 20b is anodic bonded to the silicon substrate 21 that is anodic bonded to the first glass substrate 20a. Specifically, the first conductive plate 91 is disposed in contact with the conductor 37a provided on the first glass substrate 20a, and on the other surface (the lower surface in the drawing) of the second glass substrate 20b. The second conductive plate 92 is disposed in contact with the second conductive plate 92. Then, one surface (the upper surface in the drawing) of the second glass substrate 20b and the other surface (the lower surface in the drawing) of the silicon substrate 21 are brought into contact over the entire surface. A positive voltage is applied to the first conductive plate 91 by the electrode 93 and a negative voltage is applied to the second conductive plate 92. The positive voltage applied to the first conductive plate 91 is energized to the silicon substrate 21 through the conductive film 37 provided on the first glass substrate 20a. Then, an electrostatic attractive force is generated between the silicon substrate 21 and the second glass substrate 20b, and the mutually contacted surfaces are chemically bonded. In this way, the second glass substrate 20b and the silicon substrate 21 are anodically bonded. During the anodic bonding, the second glass substrate 20b is heated to 200 to 400 ° C. by a heater built in the second conductive plate 92. The applied voltage is set to 200 to 600 V as in the case of anodic bonding of the first glass substrate 20a.

  By taking the above steps, the gyro sensor 2b (2) shown in FIG. 5 can be manufactured. The gyro sensor 2b (2) manufactured in this way has the following effects. That is, in the conductor embedding process, the conductor 37a is provided in the through hole 40 (40a, 40b, 40c) provided in the first glass substrate in the through hole forming process, and is provided by etching the silicon substrate 21. It is electrically connected to the frame 33 and the post 34 which are columnar portions. Therefore, when a voltage is applied to the conductor 37a via the first conductive plate 91 while the glass substrate 20a is interposed between the first conductive plate 91 and the silicon substrate 21, The applied voltage energizes the conductive film 37 and applies the voltage to the frame 33 and the post 34 that are the columnar portions of the silicon substrate 21.

  Thus, in the second anodic bonding step of anodic bonding the second glass substrate 20b and the silicon substrate 21, a voltage is applied to the silicon substrate 21 in the same manner as the anodic bonding of the first glass substrate 20a and the silicon substrate 21. It can be suitably applied. Therefore, the second glass substrate 20b and the silicon substrate 21 are preferably anodically bonded. That is, the silicon substrate 21 is energized through the through-holes 40 (40a, 40b, 40c) provided in the first glass substrate 20a while being in the state through the insulating first glass substrate 20a. Therefore, it is not necessary to apply a high voltage as in the prior art, and the temperature at which the glass substrate is heated to cause the thermal diffusion of alkali metal ions is 200 as usual. A temperature of about ˜400 ° C. can be selected.

  Specifically, it is not necessary to apply a voltage of several thousand volts, which damages the electrical wiring or destroys the insulating part, and a normal voltage of 200 to 600 V is applied. It will be good. Moreover, at the time of this joining, the heating temperature can select 200-400 degreeC as usual. Therefore, the second glass substrate 20b and the silicon substrate 21 are preferably anodically bonded.

Furthermore, in the manufacturing method of this mechanical quantity sensor,
The conductor 37a has conductivity and also serves as the electrode pad 36 (36h, 36i, 36j).
Since the conductor 37a also serves as an electrode pad 36 (36h, 36i, 36j) which is an independent terminal for each of the through-holes 40 (40a, 40b, 40c), electrical connection is made using this conductor 37a. Possible terminals will be provided. Therefore, the formation process for newly providing a terminal can be omitted. As a result, the workability of the manufacturing is improved, leading to a reduction in manufacturing time and a reduction in manufacturing cost.

  In addition, since the through holes 40 (40a, 40b, 40c) are provided in the respective portions of the first glass substrate 20a that are in contact with the frame 33 and the post 34 that are columnar portions, the through holes 40 (40a, 40b, The conductor 37a provided in 40c) is suitably connected to each of the frame 33 and the post 34 which are columnar parts provided by etching the silicon substrate 21 in the detection part forming step. As a result, even when the frame 33 of the silicon substrate 21 is not in contact with the post 34, the voltages of the independent frame 33 and the post 34 are suitably applied. Each of the frame 33 and the post 34 is preferably anodically bonded to the second glass substrate 20b.

  Therefore, the sealed chamber is suitably configured by the first glass substrate 20a, the second glass substrate 20b, and the silicon substrate 21 sandwiched between these glass substrates. Therefore, the detection unit 23 for detecting various mechanical quantities such as acceleration and angular velocity can be suitably accommodated in the sealed chamber. Thus, it can be suitably used as a mechanical quantity sensor such as an acceleration sensor or an angular velocity sensor.

  With the above, according to the manufacturing method of the mechanical quantity sensor described above, the silicon substrate 21 and the pair of glass substrates 20 (20a, 20b) are anodic bonded while being a manufacturing method of the mechanical quantity sensor using the anodic bonding method. In this case, the applied voltage can be lowered to 200 to 600 V as in the case of normal anodic bonding, and the heating temperature at the time of bonding can be selected from 200 to 300 ° C. As a result, the conventional problems such as damage to the electrical wiring, destruction of the insulating portion, melting of the metal constituting the electrical wiring and the like have been solved, and the bonding strength between the silicon substrate and the glass substrate has been made favorable. A mechanical quantity sensor can be obtained.

  The sealed chamber is suitably configured by the first glass substrate 20a, the second glass substrate 20b, and the silicon substrate 21 sandwiched between the glass substrates 20a and 20b. Therefore, the detection unit 23 for detecting various mechanical quantities such as acceleration and angular velocity can be suitably accommodated in the sealed chamber. As a result, it can be suitably used as a mechanical quantity sensor such as an acceleration sensor or an angular velocity sensor, and when incorporated in an electronic device such as the electronic device 1, it can suitably detect a mechanical amount such as acceleration or angular velocity. It becomes.

The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the gyro sensor 2 capable of detecting the angular velocity is described as an example of the mechanical quantity sensor. However, the gyro sensor 2 is not limited to the gyro sensor 2, and for example, an acceleration capable of detecting an acceleration. You may comprise as a sensor. In the case of such an acceleration sensor, there is no need to forcibly excite the proof mass 32.
Further, in the manufacturing method described above, the face notch 60 is not provided. However, when the conductive film 37 is divided in the terminal forming process, as shown by reference numeral 60 in FIG. The notch 60 may be provided.

It is a block diagram which shows one Embodiment of the electronic device which has a gyro sensor which concerns on this invention. It is sectional drawing of the gyro sensor shown in FIG. 1, and a perspective view which shows the internal structure of a proof mass periphery. It is sectional drawing of the gyro sensor regarding 1st Embodiment. FIG. 4 is a cross-sectional view showing a manufacturing process of the gyro sensor shown in FIG. 3. It is sectional drawing of the gyro sensor regarding 2nd Embodiment. It is sectional drawing which shows the manufacturing process of the gyro sensor shown in FIG. It is a perspective view which shows typically the silicon substrate comprised in pillar shape.

Explanation of symbols

1 Electronic equipment 2 Gyro sensor (mechanical quantity sensor)
20 glass substrate 20a first glass substrate 20b second glass substrate 21 SOI substrate (silicon substrate)
23 detector 33 frame (columnar part)
34 post (columnar part)
40 through hole 37 conductive film 60 face notch

Claims (8)

A method of manufacturing a mechanical quantity sensor configured by sandwiching a silicon substrate between a first glass substrate and a second glass substrate,
A through hole forming step of providing a through hole in the first glass substrate;
A first anodic bonding step of anodically bonding the first glass substrate provided with the through hole and the silicon substrate;
A conductive film forming step of providing a conductive film electrically connected to the silicon substrate through the through hole on a surface of the first glass substrate opposite to a surface to which the silicon substrate is bonded;
A method of manufacturing a mechanical quantity sensor, comprising: a second anodic bonding step of anodic bonding the second glass substrate and the silicon substrate. In the manufacturing method of the mechanical quantity sensor of Claim 1,
A detection unit forming step of performing an etching process so as to form a detection unit and a columnar unit arranged around the detection unit on the silicon substrate bonded to the first glass substrate;
A method of manufacturing a mechanical quantity sensor, wherein a portion where the conductive film is electrically connected in the conductive film forming step is the columnar portion of the silicon substrate. In the manufacturing method of the mechanical quantity sensor according to claim 1 or 2,
A method of manufacturing a mechanical quantity sensor, comprising: a terminal forming step of dividing the conductive film and providing an independent terminal for each through hole. A method of manufacturing a mechanical quantity sensor configured by sandwiching a silicon substrate between a first glass substrate and a second glass substrate,
A through hole forming step of providing a through hole in the first glass substrate;
A first anodic bonding step of anodically bonding the first glass substrate provided with the through hole and the silicon substrate;
A conductor burying step of burying a conductor electrically connected to the silicon substrate through the through hole in the through hole;
A method of manufacturing a mechanical quantity sensor, comprising: a second anodic bonding step of anodic bonding the second glass substrate and the silicon substrate. In the manufacturing method of the mechanical quantity sensor of Claim 4,
A detection unit forming step of performing an etching process so as to form a detection unit and a columnar unit arranged around the detection unit on the silicon substrate bonded to the first glass substrate;
The method of manufacturing a mechanical quantity sensor, wherein a portion where the conductor is electrically connected in the conductor burying step is the columnar portion of the silicon substrate. In the manufacturing method of the mechanical quantity sensor as described in any one of Claims 1-5,
The method for manufacturing a mechanical quantity sensor, wherein the positions where the through holes are provided are the respective positions in contact with the columnar portion of the first glass substrate.   A mechanical quantity sensor manufactured by the method of manufacturing a mechanical quantity sensor according to any one of claims 1 to 6. An electronic apparatus comprising: a mechanical quantity sensor manufactured by the method for manufacturing a mechanical quantity sensor according to claim 1.

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