JP4496918B2 - Semiconductor device - Google Patents

Description

  The present invention relates to a semiconductor device having a Hall element on a substrate surface, and more particularly to a semiconductor device that is particularly suitable for use as a magnetic sensor.

  As is well known, since the Hall element can detect the angle without contact, it is mounted on a so-called Hall IC or the like and used as an angle detection sensor such as a throttle valve opening sensor of an in-vehicle internal combustion engine as a magnetic sensor, for example. It is done. First, the magnetic detection principle of the Hall element will be described with reference to FIG.

  When a magnetic field (magnetism) perpendicular to the current flowing in the material is applied, an electric field (voltage) is generated in a direction perpendicular to both the current and the magnetic field. That is, when a magnetic field is applied, the moving carrier receives Lorentz force and is bent in a direction perpendicular to both the movement (movement) direction of the carrier and the direction of the magnetic field. Thus, carriers accumulate on one side of the substance, and an electric field (voltage) is generated in the bent direction of the carriers. This phenomenon is called the Hall effect, and the voltage generated here is called the Hall voltage.

For example, when a conductor 100 as shown in FIG. 7 is considered, the width of the conductor is W, the length is L, the thickness is d, the angle between the conductor 100 and the magnetic field is θ, the magnetic flux density is B, and the drive is performed. When the current (current supplied between the terminals TI and TI ′) is I, the Hall voltage (voltage generated between the terminals TV _{H and} TV _H ′) V _H is
V _H = (R _H IB / d) cos θ, R _H = 1 / (qn)
It can be expressed as Here, R _H is the Hall coefficient, q is the charge, and n is the carrier concentration.

As can be seen from the above relational expression, the Hall voltage V _H changes in accordance with the angle θ formed by the Hall element (conductor) and the magnetic field, so that the angle can be detected by using this. Thus, the above-described angle detection sensor can be realized by using the Hall element.

  Conventionally, as described in, for example, Patent Document 1, a semiconductor device including a Hall element on the surface of a semiconductor substrate is known. FIG. 8 shows a schematic structure of this semiconductor device as a perspective view.

  As shown in FIG. 8, in this semiconductor device, a Hall element (not shown) is formed in the Hall element formation region HE provided on the surface of the semiconductor substrate, and the terminals T1 to T4 of the Hall element are They are electrically connected to the electrodes ED11 to ED14 through wirings W11 to W14, respectively. Although not shown, the semiconductor substrate is sealed (molded) with an appropriate sealing material (mold resin) for mechanical protection and chemical protection. Here, the semiconductor substrate includes a semiconductor layer 11a and a semiconductor region 11b formed thereon by epitaxial growth, and the electrodes ED11 to ED14 supply a drive current to the Hall element. This corresponds to an electrode (electrode pair) for performing the operation and an electrode (electrode pair) for extracting a Hall voltage signal from the Hall element. The Hall element formation region HE is provided for a cantilever portion formed with a groove S around it.

By the way, for example, when an external force is applied to the semiconductor substrate, the substrate is bent or twisted, and nonuniform stress is applied to the entire substrate. Then, due to the piezoresistive effect, the resistance bridge as an equivalent circuit of the resistance component inside the Hall element becomes unbalanced, and when an offset voltage (unbalanced voltage) is generated, the detection accuracy as the magnetic detection element is lowered. . Since the offset voltage has a characteristic that fluctuates greatly with a temperature change, when the offset voltage is generated, the temperature change is a factor that lowers the detection accuracy. In this respect, this semiconductor device adopts a cantilever structure in order to prevent the external force from being transmitted to the Hall element formation region HE when an external force is applied to the outer periphery of the substrate. The connection with is set to a minimum. As described above, by increasing the resistance to the external force on the substrate, high detection accuracy as the magnetic detection element is maintained.
Japanese Patent Laid-Open No. 9-97895

  However, in the semiconductor device illustrated in FIG. 8, although the influence on the Hall element is mitigated with respect to the application of stress in the Y direction in FIG. 8, the application of the stress in the X direction in FIG. The impact has not been fully mitigated, and there is still room for improvement. Further, when the semiconductor substrate is in a high-pressure environment or an environment with large pressure fluctuations, the influence due to the pressure, that is, the stress based on the pressure is applied to the Hall element in the Hall element formation region HE, and is applied to the substrate. As in the case where an external force is applied, the detection accuracy is reduced. Further, the stress due to the sealing material (mold resin) cannot be ignored, and this also causes a decrease in detection accuracy. In the conventional semiconductor device illustrated in FIG. 8 above, the environment surrounding such a device and the influence of the sealing material cannot be reduced, and the detection accuracy as a magnetic detection element is significantly lowered.

  The present invention has been made in view of such circumstances, and provides a semiconductor device capable of maintaining high detection accuracy as a magnetic detection element without depending on the environment surrounding the device and the material of the sealing material. Objective.

To achieve these objectives, the invention described in claim 1, the surface of the semiconductor substrate, to form a Hall element for outputting a Hall voltage signal based on the application of the magnetic field with respect to the drive current, on the Hall element Rutotomoni provided a cap for sealing at least the Hall element in a vacuum in a manner to form a vacuum chamber, the back surface side of the semiconductor substrate provided with a cap to form a vacuum chamber in response to the area where the Hall element Structure.

According to such a structure, since the Hall element is sealed in a vacuum, the influence on the Hall element by the environment surrounding the device and the sealing material is negligibly small. That is, the application of stress to the Hall element based on the environmental pressure or the sealing material is suppressed, and the detection accuracy as the magnetic detection element is maintained high. In addition, due to the heat insulation effect due to the vacuum, the temperature change of the Hall element due to the change of the environmental temperature (outside air temperature) is reduced, and this also increases the detection accuracy.
In addition, by providing a cap as described above also on the back surface side of the semiconductor substrate, vacuum chambers are provided on both the front and back surfaces of the Hall element. That is, the application of stress to the Hall element and the temperature change are further suppressed, and the detection accuracy as the magnetic detection element is further maintained. In addition, by providing caps on both surfaces (front and back surfaces) of the Hall element, stress due to joining of the caps can be canceled out on both surfaces.

According to a second aspect of the present invention, on the premise of the above structure, a signal processing circuit for performing predetermined signal processing on the Hall voltage signal output from the Hall element is further formed on the surface of the semiconductor substrate. Te, by the Hall elements and the original cooperation with the signal processing circuit and to configure the magnetic sensor for detecting a magnetic field applied from a predetermined direction, the cap provided on the surface side of the semiconductor substrate, the Hall element, including the signal processing circuit so as Ru is sealed in a vacuum. With such a structure, a required magnetic sensor can be realized, and the magnetic detection accuracy of such a magnetic sensor is maintained high.

Moreover, in realizing these structures, for example, as described in claim 3,
The Hall element is formed in the recess of the semiconductor substrate, and the cap provided on the surface side of the semiconductor substrate is provided in the form of a vacuum chamber formed on the Hall element as a space formed by the recess. Construction.
Or as claimed in claim 4,
A structure in which the cap provided on the surface side of the semiconductor substrate has a recess, and a space by the recess is a vacuum chamber formed on the Hall element .
It is effective to adopt such a structure. Thus, by providing a recess in the semiconductor substrate or the cap provided on the surface side of the semiconductor substrate, a space (space) for forming a vacuum chamber on the Hall element is easily and appropriately secured. become.

In addition, as for the cap provided on the front surface side of the semiconductor substrate and the cap provided on the back surface side of the semiconductor substrate, it is effective that the cap is made of a glass material as described in claim 5. is there. As is well known, the glass material is a material used in a general sensor configuration such as a semiconductor pressure sensor. For this reason, by using such a glass material as a material for the cap provided on the front surface side of the semiconductor substrate and the cap provided on the back surface side of the semiconductor substrate, there is no need to add a special process, that is, existing equipment. Now you can make these caps.

In this case, the cap provided on the front surface side of the semiconductor substrate and the cap provided on the back surface side of the semiconductor substrate are joined to the semiconductor substrate by anodic bonding as described in claim 6. It is more effective in securing the airtightness of the vacuum chamber. Anodic bonding removes alkali components (mainly Na (sodium)) contained in the glass in the vicinity of the joint by applying a high voltage between the joining members in a high temperature environment, that is, between the semiconductor substrate and the glass material. In this method, unbonded oxygen is generated therein, and the oxygen is bonded to (for example, covalently bonded to) the semiconductor substrate (for example, Si (silicon)), thereby joining the two members. That is, the glass of the joint part joined by anodic joining usually contains a smaller amount of alkali components (mainly Na) than the other parts.

According to a seventh aspect of the present invention, an electrode for supplying a driving current to the Hall element and a Hall voltage signal from the Hall element are extracted outside a cap provided on the surface side of the semiconductor substrate. When the electrodes are formed in a form that is drawn out from the respective terminals of the Hall element by wiring, the wiring that pulls out each of these electrodes to the outside of the cap provided on the surface side of the semiconductor substrate , It is effective that the semiconductor substrate is formed as a diffusion layer in which the impurity concentration in the surface portion is selectively increased.

Incidentally, the wiring to draw the respective electrodes to the outside of the cap provided on the surface side of the semiconductor substrate, in a case where it was formed by the ordinary metal film made of aluminum or copper, the semiconductor substrate surface and the At the joint with the cap provided on the surface side of the semiconductor substrate , the wiring is sandwiched between these two members, and there is a concern about disconnection or the like. Furthermore, a step is formed on the surface of the substrate due to some film thickness of the metal film, and a gap is likely to be generated between the substrate and the cap, so that it is difficult to ensure airtightness. In this regard, in the above structure, since the impurity concentration of the surface portion of the semiconductor substrate is selectively increased to form a diffusion layer as the wiring there, the lead wiring portion is configured as a part of the semiconductor substrate. In addition, the airtightness of the vacuum chamber formed on the Hall element by the anodic bonding or the like can be maintained. That is, disconnection, a decrease in airtightness, and the like, which are a concern when the wiring is formed of a metal film, are preferably suppressed.

The cap provided on the surface side of the semiconductor substrate is taken out from the electrode for supplying a drive current to the Hall element and a Hall voltage signal from the Hall element as described in claim 8. By providing through holes for exposing the electrodes for the respective purposes, even when a cap is provided on the surface side of the semiconductor substrate , it is easier and more suitable through each electrode exposed by the through holes. It becomes possible to drive the Hall element.

Also, in the invention according to claim 9, in the semiconductor device according to any one of the claims 1-8, the cap provided on the back surface side of the semiconductor substrate, and has a recess, the space formed by the recess shall be kick set in the form of a vacuum chamber which is formed corresponding to the area where the Hall element. According to such a structure, a space (space) for forming a vacuum chamber corresponding to a place where the Hall element is formed can be easily secured without processing the semiconductor substrate.

An embodiment of the semiconductor device according to the present invention will be described below.
The structure of the semiconductor device according to this embodiment will be described in detail below with reference to FIGS. 1 is a perspective view schematically showing the schematic structure of the semiconductor device, FIG. 2 is a perspective view showing the schematic structure of the semiconductor device in an unbonded state, and FIG. 3 is taken along the line AA ′ of FIG. FIG.

  As shown in FIGS. 1 to 3, in this semiconductor device, a Hall element is formed in a Hall element formation region HE provided on the surface of a semiconductor substrate 1 made of, for example, silicon, and each terminal ( (Not shown) are electrically connected to the electrodes ED1 to ED4 via wirings W1 to W4, respectively. Although not shown, in the Hall element formation region HE, in addition to the Hall element, a signal processing circuit for performing predetermined signal processing on the Hall voltage signal output from the Hall element is also formed. A magnetic sensor that detects a magnetic field applied from a predetermined direction under the cooperation of the Hall element and the signal processing circuit is configured as a so-called Hall IC. The electrodes ED1 to ED4 correspond to electrodes (electrode pairs) for supplying a drive current to the Hall elements and electrodes (electrode pairs) for taking out Hall voltage signals from the Hall elements, respectively. Although not shown in the figure, the semiconductor substrate 1 is sealed (molded) with an appropriate sealing material (molded resin) for mechanical protection and chemical protection. Here, the description will be made assuming that the Hall element formed in the Hall element formation region HE is a horizontal Hall element that outputs a Hall voltage corresponding to a magnetic field component perpendicular to the substrate surface (chip surface). Instead of the Hall element, a vertical Hall element that outputs a Hall voltage corresponding to a magnetic field component parallel to the substrate surface can be used as appropriate.

  Here, the wirings W1 to W4 are formed as diffusion layers (wells) in which the impurity concentration in the surface portion of the semiconductor substrate 1 is selectively increased by, for example, ion implantation. For this reason, for example, when the wirings W <b> 1 to W <b> 4 are formed of a metal film, the wiring disconnection, the deterioration of airtightness, and the like are suppressed.

  The semiconductor substrate 1 has a vacuum chamber VS1 formed on the Hall element formation region HE, and the Hall element formed in the region HE and the signal processing circuit constituting the magnetic sensor together with the Hall element are vacuumed. A cap 2 for sealing inside is provided. More specifically, the cap 2 has a recess, and a space (space) by the recess is provided as the vacuum chamber VS1. That is, in this semiconductor device, the surface of the cap 2 is sealed with the sealing material. As a result, stress due to the sealing material is not applied to the Hall element formation region HE. Also, as shown in FIG. 1, the cap 2 is formed with semicircular through holes H1 to H4 that expose the electrodes ED1 to ED4. As a result, the electrodes ED1 to ED4 are drawn out from the terminals of the Hall elements to the outside of the cap 2 through the wires W1 to W4.

  A cap 3 for forming the vacuum chamber VS2 is also provided on the back side of the semiconductor substrate 1 corresponding to the location where the Hall element is formed. Here, the vacuum chamber VS <b> 2 is formed using a space (space) formed by a recess provided on the back side of the semiconductor substrate 1. Specifically, the recess is formed up to the vicinity of the Hall element formation region HE. The cap 3 is not formed with the previous through hole.

  The caps 2 and 3 are both made of a glass material and bonded to the semiconductor substrate 1 by anodic bonding. Thus, when the caps 2 and 3 are bonded by anodic bonding, boron oxide is added to quartz glass to lower its softening point and keep the expansion coefficient as small as possible. (Heat resistant glass) or a glass material having a composition similar to this is preferably used as the cap material. This borosilicate glass is a material that is useful for anodic bonding because it is less expensive than quartz and has excellent strength, heat resistance, and chemical stability. However, when considering compatibility with Si (silicon), which is widely used as a material for semiconductor substrates, there is a large difference in thermal expansion coefficient between general borosilicate glass and silicon. When both are joined by joining, there is a concern that residual stress due to the difference in thermal expansion coefficient between the two is generated. Therefore, when silicon is used as the material for the semiconductor substrate, a glass material or the like in which the composition of commercially available borosilicate glass is changed somewhat so that its thermal expansion coefficient is close to that of silicon is also useful as the cap material. .

FIG. 4 shows an example of a planar structure of a semiconductor substrate (wafer) before the semiconductor device is cut out as a chip (dicing).
As shown in FIG. 4, for example, each element is regularly arranged in a column and a row in a grid pattern, and is cut (diced) along a cut line (scribe line) CL indicated by a two-dot chain line in the drawing. (16 in this case) of elements (semiconductor devices) can be obtained efficiently.

  Thus, in the semiconductor device according to this embodiment, since the Hall element is sealed in a vacuum, the environment surrounding the device and the influence on the Hall element due to the sealing material are so small that they can be ignored. . That is, the application of stress to the Hall element based on the environmental pressure or the sealing material is suppressed, and the detection accuracy as the magnetic detection element is maintained high. In addition, due to the heat insulation effect due to the vacuum, the temperature change of the Hall element due to the change of the environmental temperature (outside air temperature) is reduced, and this also increases the detection accuracy.

As described above, according to the semiconductor device of this embodiment, many excellent effects as described below can be obtained.
(1) A Hall element is formed on the surface of the semiconductor substrate 1 (Hall element formation region HE), and the Hall element is sealed in a vacuum with respect to the semiconductor substrate 1 in such a manner that a vacuum chamber VS1 is formed on the Hall element. It was set as the structure which provided the cap 2 which stops. This makes it possible to maintain high detection accuracy as a magnetic detection element regardless of the environment surrounding the apparatus and the material of the sealing material.

  (2) Also, by maintaining high detection accuracy as a magnetic detection element, it becomes possible to detect minute magnetic fluctuations that have been difficult in the past, and can be applied to new fields. Even when applied to conventional fields, yields can be improved, costs can be reduced, and energy can be saved.

  (3) Furthermore, the degree of freedom in selecting the material for the sealing material is also increased. Conventionally, in order to suppress the stress caused by the sealing material, a material having a small stress is sometimes used as the material of the sealing material. However, according to the semiconductor device, since the influence of the stress due to the sealing material is so small that it can be ignored, it is not necessary to consider the stress when selecting the material of the sealing material. The degree of freedom in selecting materials will be increased.

  (4) A signal processing circuit for performing predetermined signal processing on the Hall voltage signal output from the Hall element is further formed on the surface of the semiconductor substrate 1, and the Hall element and the signal processing circuit cooperate with each other. A magnetic sensor that detects a magnetic field applied from a predetermined direction is configured, and the cap 2 is sealed in a vacuum together with a Hall element and a signal processing circuit. Thereby, a required magnetic sensor can be realized, and the magnetic detection accuracy of such a magnetic sensor is maintained high.

  (5) The cap 2 has a recess, and the space by the recess is provided as a vacuum chamber VS1. Thus, by providing the cap 2 with the recess, a space (space) for forming the vacuum chamber VS1 can be easily and appropriately secured.

  (6) A glass material was adopted as the material for the caps 2 and 3. As is well known, a glass material such as borosilicate glass is a material used in a general sensor configuration such as a semiconductor pressure sensor. For this reason, by using such a glass material as the material of the caps 2 and 3, such a cap can be formed without adding a special process, that is, with existing equipment.

  (7) For the caps 2 and 3, it is more effective to secure the airtightness of the vacuum chambers VS1 and VS2 by joining the caps 2 and 3 to the semiconductor substrate 1 by anodic bonding.

  (8) The electrodes ED1 to ED4 are formed outside the cap 2 on the surface of the semiconductor substrate 1, and wirings W1 to W4 for leading the electrodes ED1 to ED4 to the outside of the cap 2 are formed on the surface portion of the semiconductor substrate 1. It was decided to form as a diffusion layer in which the impurity concentration was selectively increased. Thereby, suppression of disconnection of the said wiring W1-W4, a fall of airtightness, etc. will be aimed at.

  (9) The cap 2 is provided with through holes H1 to H4 that expose the electrodes ED1 to ED4. Thereby, even when the cap 2 is provided, the Hall element can be more easily and suitably driven through the electrodes ED1 to ED4 exposed through the through holes H1 to H4. Also, as shown in FIG. 4, such a structure provided with the through holes H1 to H4 is useful for facilitating the manufacture of the semiconductor device.

  (10) The cap 3 for forming the vacuum chamber VS2 corresponding to the location where the Hall element is formed (Hall element formation region HE) is also provided on the back side of the semiconductor substrate 1. By further providing such a cap 3, vacuum chambers VS1 and VS2 are provided on both sides of the front and back surfaces of the Hall element. That is, the application of stress to the Hall element and the temperature change are further suppressed, and the detection accuracy as the magnetic detection element is further maintained. In addition, by providing the caps 2 and 3 on both surfaces (front and back surfaces) of the Hall element, the stress caused by the joining of the caps 2 and 3 can be canceled by both surfaces.

  (11) Further, the recess on the back surface side of the semiconductor substrate 1 is formed to the vicinity of the Hall element formation region HE. Thereby, the heat insulation effect by the vacuum chamber VS2 is further enhanced.

In addition, the said embodiment can also be implemented with the following aspects.
As shown in FIG. 5, without forming a recess in the cap 2, for example, a recess dug down by “several μm to several tens of μm” is formed in the semiconductor substrate 1, and the Hall element is formed on the bottom of the recess. The region HE may be provided, and the vacuum chamber VS1 may be formed using a space (space) formed by the concave portion. In addition, if the said recessed part is about "several micrometers", it is desirable to form by selectively oxidizing the board | substrate surface, for example with photolithography, and etching-removing the oxide film with a hydrofluoric acid. Further, if it is about “several tens of μm”, it is desirable to form by using trench etching widely used for element isolation, wet etching with KOH solution, or the like. Even with such a structure, the same effects as the effects (1) to (11) or an effect equivalent thereto can be obtained. Furthermore, since it is not necessary to form a recess in the cap 2, it is possible to use planar glass (planar glass) as the cap 2. FIG. 5 corresponds to the cross-sectional view of FIG. 3. In FIG. 5, the same elements as those shown in FIG. 3 are denoted by the same reference numerals.

  As shown in FIG. 6, the caps 2 and 3 may have a recess, and the vacuum chambers VS1 and VS2 may be formed using a space (space) by the recess. Even with such a structure, the same effects as the effects (1) to (11) or an effect equivalent thereto can be obtained. Furthermore, since a space for forming a vacuum chamber is easily secured without forming a recess in the semiconductor substrate 1, processing on the substrate can be minimized.

-In above-mentioned embodiment, although the through-holes H1-H4 and the recessed part of the cap 2 were formed circularly, you may form not only this but polygonal shapes, such as a square and an octagon, for example.
In the above embodiment, the cap 2 is provided with the through holes H1 to H4 that expose the electrodes ED1 to ED4. However, this is not an essential configuration.

  In the above embodiment, the wirings W1 to W4 are formed as diffusion layers in which the impurity concentration in the surface portion of the semiconductor substrate 1 is selectively increased. However, this is not an essential configuration. For example, these wirings W1 to W4 may be formed of a metal film.

  In the above embodiment, anodic bonding is adopted as the bonding method for the caps 2 and 3. However, the bonding method for these caps is arbitrary as long as sufficient airtightness can be obtained as the vacuum chamber VS1. It is.

  In the above embodiment, a glass material is adopted as the material for the caps 2 and 3. However, these cap materials are sufficient if they can be vacuum-sealed, and other materials such as ceramics can also be used.

Further, the cap 2 and the cap 3 can be similarly applied to a semiconductor device having a cantilever structure as shown in FIG.
In the above embodiment, the cap 3 for forming the vacuum chamber VS2 corresponding to the location where the Hall element is formed is also provided on the back side of the semiconductor substrate 1. However, this is not an essential configuration, and the cap 3 may be omitted.

In the above embodiment, the cap 2 seals the signal processing circuit in the vacuum together with the Hall element. However, only the Hall element may be sealed in a vacuum.
In the above embodiment, Si (silicon) is used as the material of the semiconductor substrate 1, but the material of the substrate is arbitrary, and other substrate materials are used in consideration of compatibility with the caps 2 and 3. You may make it employ | adopt. For example, a compound semiconductor material such as GaAs (gallium arsenide), InSb (indium antimony), InAs (indium arsenide), SiC (silicon carbide), and other semiconductor materials such as Ge (germanium) can be appropriately employed. In particular, GaAs and InAs are materials having excellent temperature characteristics, and are effective in increasing the sensitivity of the Hall element.

  After all, if the structure is such that a cap for sealing the Hall element formed on the surface of the semiconductor substrate in a vacuum is provided on the substrate, the same effects as in the above (1) to (3) An effect or an equivalent effect can be obtained.

1 is a perspective view schematically showing a schematic structure of a semiconductor device according to an embodiment of the present invention. The perspective view which shows schematic structure of the semiconductor device which concerns on the embodiment in the cap unjoined state. FIG. 2 is a cross-sectional view taken along line A-A ′ of FIG. 1. The top view which shows an example of the planar structure of the semiconductor substrate (wafer) before cutting out this semiconductor device as a chip | tip (dicing). Sectional drawing which shows the modification of the semiconductor device which concerns on the same embodiment. Sectional drawing which shows another modification of the semiconductor device which concerns on the same embodiment. The perspective view which shows the magnetic detection principle of a Hall element. The perspective view which shows typically the schematic structure of the semiconductor device about an example of the conventional semiconductor device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate, 2, 3 ... Cap, ED1-ED4 ... Electrode, H1-H4 ... Through-hole, HE ... Hall element formation area, VS1, VS2 ... Vacuum chamber, W1-W4 ... Wiring.

Claims (9)

On the surface of the semiconductor substrate, it is formed Hall element which outputs a Hall voltage signal is based on the application of the magnetic field with respect to the drive current, sealing at least the Hall element in a vacuum in a manner to form a vacuum chamber on the hall element It provided a cap for sealing with a Rutotomoni, on the back side of the semiconductor substrate, and wherein a cap to form a vacuum chamber in response to the area where the Hall element is provided. A signal processing circuit that performs predetermined signal processing on the Hall voltage signal output from the Hall element is further formed on the surface of the semiconductor substrate, and the Hall element and the signal processing circuit cooperate with each other. The magnetic sensor for detecting the magnetic field applied from a predetermined direction is configured, and a cap provided on the surface side of the semiconductor substrate seals the Hall element including the signal processing circuit in a vacuum. The semiconductor device according to claim 1. The Hall element is formed in a recess of the semiconductor substrate, and a cap provided on the surface side of the semiconductor substrate is provided in the form of a space formed by the recess serving as a vacuum chamber formed on the Hall element. Item 3. The semiconductor device according to Item 1 or 2. 3. The semiconductor according to claim 1, wherein the cap provided on the surface side of the semiconductor substrate has a recess, and the space formed by the recess serves as a vacuum chamber formed on the Hall element. apparatus. The semiconductor device according to claim 1, wherein the cap provided on the front surface side of the semiconductor substrate and the cap provided on the back surface side of the semiconductor substrate are made of a glass material. The semiconductor device according to claim 5, wherein the cap provided on the front surface side of the semiconductor substrate and the cap provided on the back surface side of the semiconductor substrate are joined to the semiconductor substrate by anodic bonding. Outside the cap provided on the surface side of the semiconductor substrate, an electrode for supplying a drive current to the Hall element, and an electrode for taking out a Hall voltage signal from the Hall element are respectively provided on the Hall element. 2. The wiring that is formed in such a manner as to be drawn out from a terminal by wiring, and that leads out of each electrode to the outside of the cap, is formed as a diffusion layer in which the impurity concentration of the surface portion of the semiconductor substrate is selectively increased. The semiconductor device as described in any one of -6. The cap provided on the surface side of the semiconductor substrate is provided with a through hole for exposing an electrode for supplying a driving current to the Hall element and an electrode for extracting a Hall voltage signal from the Hall element. The semiconductor device according to any one of claims 1 to 7. The cap provided on the back surface side of the semiconductor substrate has a recess, and is provided in the form of a vacuum chamber formed corresponding to the formation position of the Hall element by a space formed by the recess . the semiconductor device according to any one of 8.

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