JP5678418B2 - Semiconductor device - Google Patents

Description

  The present invention relates to a semiconductor device provided with a temperature detection element.

  When the semiconductor device operates, the semiconductor device may generate heat. In particular, in a power semiconductor device such as an IGBT through which a large current flows, the amount of generated heat tends to increase. In order to detect heat generated by the semiconductor device, a temperature sensor may be installed in the semiconductor device. For example, in Patent Document 1, diodes are installed as temperature detection elements at the center and the end of the surface of a semiconductor substrate. This semiconductor device detects the temperature of diodes installed at two locations, and controls the gate voltage and the like so as to make the surface temperature of the semiconductor device more uniform.

JP 2007-234850 A

  In the technique of Patent Document 1, since the temperature detection element is installed only for the purpose of uniformizing the surface temperature of the semiconductor device, the two temperature detection elements are both installed on the surface of the semiconductor substrate. However, when heat is generated inside the semiconductor substrate (for example, in the case of a vertical semiconductor device in which a current flows through the semiconductor substrate in the vertical direction), the temperature rises inside the semiconductor substrate rather than the surface of the semiconductor substrate. It is easy to happen. In the technique of Patent Document 1, even if the inside of the semiconductor substrate is heated due to heat generation of the semiconductor substrate, this heat generation cannot be detected unless the surface temperature of the semiconductor substrate rises. Further, even if heat generation of the semiconductor device is detected by a temperature detection element installed on the surface of the semiconductor substrate, it cannot be determined at which position in the depth direction of the semiconductor substrate the heat generation. In order to know the position of the location that caused the heat generation, it is necessary to further observe the cross section.

In the present invention, the semiconductor substrate in which the main active region is formed, the first temperature detection element for detecting the temperature of the semiconductor substrate, and the second temperature detection for detecting the temperature at a position deeper than the first temperature detection element. A semiconductor device including the element is provided. In this semiconductor device, the first temperature detection element and the second temperature detection element are provided in an isothermal region on the surface of the semiconductor substrate.

  According to the present invention, the first temperature detection element and the second temperature detection element can detect the temperatures at two positions where the depth of the semiconductor substrate is different. When heat is generated inside the semiconductor substrate, it is possible to detect the temperature inside the semiconductor substrate, which is likely to increase the temperature. Therefore, it is easy to detect the heat generation inside the semiconductor substrate. Since the temperature inside and on the surface side of the semiconductor substrate can be detected, it is possible to estimate the position in the depth direction of the location where heat is generated in the semiconductor substrate.

  In addition, since the temperature distribution in the depth direction of the semiconductor substrate can be detected by arranging the depth at which the second temperature detection element is arranged at a position where heat generation is expected, the temperature distribution in the depth direction is known. be able to.

Further, the first temperature sensing element and the second temperature sensing element, because it is provided in the constant temperature region of the semiconductor substrate surface, while reducing the influence of the temperature distribution in the planar direction of the semiconductor substrate, a semiconductor substrate depth The temperature distribution in the vertical direction can be detected.

  The first temperature detection element and the second temperature detection element are preferably adjacent to each other in the planar direction of the semiconductor substrate. Even in this case, the temperature distribution in the depth direction of the semiconductor substrate can be detected in a state where the influence of the temperature distribution in the planar direction of the semiconductor substrate is reduced.

  It is preferable that the first temperature detection element and the second temperature detection element are installed at a position that is a central portion in the planar direction of the semiconductor substrate. A temperature rise due to heat generation of the semiconductor substrate is more likely to occur in the central portion in the planar direction of the semiconductor substrate than in the end portion. For this reason, if the temperature distribution in the depth direction of the semiconductor substrate is measured at this central portion, the detection sensitivity is improved.

  The second temperature detection element is formed from the surface of the semiconductor substrate toward the inside, and has a trench in which an insulating film is formed on the inner wall surface, and a first conductivity type first formed at the bottom of the trench. A semiconductor region, a second conductivity type second semiconductor region formed at the bottom of the trench and in contact with the first semiconductor region; a first electrode in contact with the first semiconductor region but not in contact with the second semiconductor region; It is preferable to include a second electrode that is in contact with the semiconductor region and not in contact with the first semiconductor region, and an insulator that separates the first electrode and the second electrode.

  According to the present invention, since the temperature distribution in the depth direction of the semiconductor substrate can be detected, it becomes easy to detect the heat generation of the semiconductor device. Since the temperature inside and on the surface side of the semiconductor substrate can be detected, it is possible to estimate the position in the depth direction of the location where heat is generated in the semiconductor substrate.

FIG. 3 is a plan view of the semiconductor device of Example 1; The enlarged view of the II-II line cross section of FIG. The enlarged view of the trench bottom part in the III-III line cross section of FIG. 3 is a conceptual diagram of a temperature distribution in the depth direction of a semiconductor substrate during normal operation of the semiconductor device of Example 1. FIG. 2 is a conceptual diagram of a temperature distribution in the depth direction of a semiconductor substrate when a short circuit occurs in the semiconductor device of Example 1. FIG. The conceptual diagram which compares the temperature difference of the depth direction at the time of normal operation of the semiconductor device of Example 1, and the time of a short circuit occurrence. The top view of the semiconductor device of a modification. The conceptual diagram of the surface temperature distribution of a semiconductor substrate. Sectional drawing of the semiconductor device of a modification. Sectional drawing of the semiconductor device of a modification. Sectional drawing of the semiconductor device of a modification. Sectional drawing of the semiconductor device of a modification. Sectional drawing of the semiconductor device of a modification. Sectional drawing of the temperature detection element of a modification. Sectional drawing of the temperature detection element of a modification. Sectional drawing of the temperature detection element of a modification.

The main features of the embodiments described below are listed below.
(Feature 1) A vertical IGBT is formed in the main active region.
(Feature 2) At least one of the temperature detection elements is provided at a position for detecting the temperature of the depth of the drift region near the body region of the IGBT.

  Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a semiconductor device 100 according to the present embodiment, FIG. 2 is an enlarged view of a cross section taken along line II-II of the semiconductor device 100 shown in FIG. 1, and FIG. It is an enlarged view of the trench bottom part in the III-III line cross section.

  As shown in FIG. 1, the semiconductor device 100 includes a semiconductor substrate 10 including a main active region 1 and a temperature detection region 2. In the temperature detection region 2, a first temperature detection element 3 and a second temperature detection element 5 are formed. A vertical IGBT is formed in the main active region 1 of the semiconductor substrate 10.

  As shown in FIG. 1, the first temperature detection element 3 and the second temperature detection element 5 are provided in a central portion (a central portion in the planar direction) when the semiconductor substrate 10 is viewed in plan, and are adjacent to each other. ing. In the present embodiment, the first temperature detection element 3 and the second temperature detection element 5 are both diodes. Cathode pads 32 and 52 and anode pads 34 and 54 are formed on the periphery of the surface of the semiconductor substrate 10.

As shown in FIG. 2, the semiconductor substrate 10 has a P ⁺ -type collector region 101, an N-type buffer region 102, an N ⁻ -type drift region 103, and a P-type body region 104 stacked in order from the back surface side. Yes.

In main active region 1, N ⁺ -type emitter region 105 and P ⁺ -type body contact region 106 are formed on the surface of body region 104. Emitter region 105 and body contact region 106 are isolated from drift region 103 by body region 104. A trench gate 130 that penetrates through the body region 104 and reaches the drift region 103 from the surface side of the semiconductor substrate 10 is provided. The emitter region 105 is in contact with the side surface of the trench gate 130. A gate insulating film is formed on the inner wall surface of the trench of the trench gate 130, and the gate electrode is filled in the gate insulating film. The upper surface of the trench gate 130 is covered with an insulating film 41 formed on the surface of the semiconductor substrate 10.

  As shown in FIG. 2, the first temperature sensing element 3 includes a trench 301 in which an insulating film is formed on the inner wall surface, an N-type first semiconductor region 303 formed at the bottom of the trench 301, and a trench A P-type second semiconductor region 305 that is formed at the bottom of 301 and is in contact with the first semiconductor region 303 is provided. The first semiconductor region 303 becomes a cathode region of the diode, and the second semiconductor region 303 becomes an anode region of the diode.

  The trench 301 is provided from the surface side of the semiconductor substrate 10 to the body region 104, and does not reach the drift region 103. The first semiconductor region 303 and the second semiconductor region 305 in the trench 301 are located in the body region 104. Thereby, the first temperature detection element 3 can detect the temperature at the position of the body region 104 of the main active region 1 of the semiconductor substrate 10.

  As shown in FIG. 2, the second temperature detection element 5 is formed at a deeper position on the semiconductor substrate 10 than the first temperature detection element 3. The second temperature detection element 5 is formed from the surface on the body region 104 side of the semiconductor substrate 10 toward the inside. The second temperature detection element 5 is formed at a trench 501 having an insulating film formed on its inner wall surface, an N-type first semiconductor region 503 formed at the bottom of the trench 501, and a bottom of the trench 501. And a P-type second semiconductor region 505 in contact with the first semiconductor region 503. The first semiconductor region 503 becomes a cathode region of the diode, and the second semiconductor region 503 becomes an anode region of the diode.

  The trench 501 penetrates the body region 104 from the surface side of the semiconductor substrate 10 and reaches the drift region 103. The bottom of the trench 501 has the same depth as the bottom of the trench gate 130 in the main active region 1, and the first semiconductor region 503 and the second semiconductor region 505 are located in the drift region 103 near the body region 104. Thereby, the second temperature detection element 5 can detect the temperature at the position of the drift region 103 in the vicinity of the body region 104 in the main active region 1 of the semiconductor substrate 10. That is, the second temperature detection element 5 detects the temperature at a position deeper in the semiconductor substrate 10 than the first temperature detection element 3.

  An insulating film 43 is formed on the surface of the semiconductor substrate 10 provided with the first temperature detecting element 3, and an insulating film 45 is formed on the surface of the semiconductor substrate 10 provided with the second temperature detecting element 5. Has been.

  A configuration of the first semiconductor region and the second semiconductor region constituting the diode will be described with reference to FIG. 3 which is an enlarged view of the bottom of the trench 501 of the second temperature detection element 5. FIG. 3 shows a part of a cross section in a direction perpendicular to the cross section shown in FIG. The bottom of the trench 301 of the first temperature detection element 3 has the same configuration as that of the second temperature detection element 5.

  As shown in FIG. 3, an N-type first semiconductor region 503 and a P-type second semiconductor region 505 are stacked at the bottom of the trench 501, and a first electrode 523 and a second electrode are formed on the surface side thereof. 525 and an insulator 507 are provided. A portion of the first semiconductor region 503 protrudes upward (on the second semiconductor region 505 side), and is in contact with the first electrode 523 at the protruding portion. The second semiconductor region 505 is in contact with the second electrode 525. The insulator 507 isolates the first electrode 523 and the second electrode 525 and isolates the first electrode 523 and the second semiconductor region 525. Accordingly, the first electrode 523 is in contact with only the first semiconductor region 503 and is not in contact with the second semiconductor region 505. The second electrode 525 is in contact with only the second semiconductor region 505 and is not in contact with the first semiconductor region 503.

  The first electrode 523 is a cathode electrode in contact with the first semiconductor region 503 that becomes the cathode region of the diode. The first electrode 523 shown in FIG. 3 and the cathode pad 52 shown in FIG. 1 are connected by wiring formed on the surface of the semiconductor substrate 10 shown in FIG. The second electrode 525 is an anode electrode in contact with the second semiconductor region 505 serving as the anode region of the diode. The second electrode 525 shown in FIG. 3 and the anode pad 54 shown in FIG. 1 are connected by a wiring formed on the surface of the semiconductor substrate 10 shown in FIG.

  As described above, in this embodiment, the semiconductor device 100 includes the semiconductor substrate 10 in which the main active region 1 is formed, the first temperature detection element 3 that detects the temperature of the semiconductor substrate 10, and the first temperature detection element 3. And a second temperature detecting element 5 for detecting the temperature at a deep position of the semiconductor substrate 10. The first temperature detection element 3 and the second temperature detection element 5 can detect temperatures at two different positions in the depth direction of the semiconductor substrate 10 and can grasp the temperature distribution in the depth direction.

  Further, the first temperature detection element 3 and the second temperature detection element 5 are adjacent to each other on the surface of the semiconductor substrate 10. That is, the first temperature detection element 3 and the second temperature detection element 5 are located adjacent to each other in the planar direction. Therefore, the temperature distribution in the depth direction of the semiconductor substrate 10 can be detected in a state where there is almost no influence from the temperature distribution in the planar direction of the semiconductor substrate 10.

  In addition, the first temperature detection element 3 and the second temperature detection element 5 are installed at a position that is a central portion (a central portion in the planar direction) when the semiconductor substrate 10 is viewed in plan. The central portion of the semiconductor substrate 10 in the planar direction is more likely to increase in temperature due to heat generation of the semiconductor substrate 10 than the end portion. If the 1st temperature detection element 3 and the 2nd temperature detection element 5 are installed in the position where such a temperature rise is easy to generate | occur | produce, detection sensitivity will improve.

  In addition, since the bottom of the trench 501 of the second temperature detection element 5 has the same depth as the bottom of the trench gate 130 in the main active region 1, the second temperature detection and the trench gate 130 in the main active region 1 in the manufacturing process. An element trench 501 can be formed simultaneously. The manufacturing process of the semiconductor device 100 can be simplified.

FIG. 4 is a diagram conceptually showing an example of the temperature distribution in the depth direction at the center in the planar direction of the semiconductor substrate 10 during normal operation. As shown in FIG. 4, at the time of normal operation, the temperature of the semiconductor substrate 10 is in a state of gradually rising as a whole from the front surface or the back surface thereof. In the depth direction of the semiconductor substrate 10, the temperature of the drift region 103 in the vicinity of the boundary between the body region 104 and the drift region 103 rises most, and in the vicinity of this boundary, the temperature in the depth direction is T _max1 , which is the maximum temperature. Become.

  In the present embodiment, the first temperature detection element 3 is installed at a position where the temperature in the body region 104 of the semiconductor substrate 10 can be detected, and the second temperature detection element 5 drifts with the body region 104 of the semiconductor substrate 10. It is installed at a position where the temperature of the drift region 103 in the vicinity of the boundary with the region 103 can be detected. In the inspection process at the time of manufacturing the semiconductor device 100, when the semiconductor substrate 10 generates heat, by knowing the detection values of the first temperature detection element 3 and the second temperature detection element 5, the position where the heat generation has occurred is estimated. be able to.

  For example, if the temperature on the surface side of the semiconductor substrate 10 detected by the first temperature detection element 3 is higher than normal and the temperature inside the semiconductor substrate 10 detected by the second temperature detection element 5 is normal, the semiconductor It can be estimated that abnormal heat is generated on the surface side of the substrate 10. Further, when the temperature on the front surface side of the semiconductor substrate 10 detected by the first temperature detection element 3 is normal and the temperature inside the semiconductor substrate 10 detected by the second temperature detection element 5 is high, the semiconductor substrate It can be estimated that abnormal heat is generated inside 10 or on the back side.

  Also in the inspection process at the time of manufacturing the semiconductor device 100, by knowing the detection values of the first temperature detection element 3 and the second temperature detection element 5, it is possible to easily estimate or grasp the position where the heat generation has occurred. And when this heat generation is recognized as an abnormal heat generation, it can be fed back to the manufacturing process of a product manufactured thereafter. This can contribute to improving the efficiency of the manufacturing process of the semiconductor device 100 and improving the yield.

Further, according to the present embodiment, it is possible to easily check the occurrence of a short circuit in the semiconductor device 100. FIG. 5 is a diagram conceptually illustrating an example of the temperature distribution in the depth direction at the center in the planar direction of the semiconductor substrate 10 when a short circuit occurs. When a short circuit occurs, the energy density applied to the semiconductor substrate 10 is higher than that during normal operation. For this reason, as shown in FIG. 5, the temperature distribution in the depth direction of the semiconductor substrate 10 is in a state where a sudden rapid temperature rise occurs locally. In the depth direction of the semiconductor substrate 10, the temperature of the drift region 103 in the vicinity of the boundary between the body region 104 and the drift region 103 is the highest temperature as in normal operation, and this temperature is T _max2 . The maximum temperature T _max2 > the maximum temperature T _max1 , and the temperature rises rapidly in the vicinity of the position where the maximum temperature T _max2 is reached, while the temperature near the front surface side and the back surface side of the semiconductor substrate 10 is the same as that during normal operation. Distribution (see FIGS. 4 and 5).

  In the present embodiment, the position of the drift region 103 in the vicinity of the boundary between the body region 104 and the drift region 103 is detected in order to detect the temperature at the maximum temperature in the depth direction of the semiconductor substrate 10 during normal operation and when a short circuit occurs. The second temperature detecting element 5 is installed in the. The position where the maximum temperature in the depth direction of the semiconductor substrate 10 is a position where the temperature rises easily even when a short circuit occurs. Since the temperature at a position where a temperature rise is likely to occur at the time of a short circuit can be detected, the detection sensitivity of the temperature rise at the time of a short circuit can be improved. Note that the position where the maximum temperature is reached may be examined by experiment or simulation, and the second temperature detection element 5 may be installed at that position.

  In the present embodiment, the first temperature detection element 3 is installed so that the temperature at a shallower position on the surface side of the semiconductor substrate 10 than the second temperature detection element 5 can be detected. 6 is a diagram conceptually showing detection values of the first temperature detection element 3 and the second temperature detection element 5 at the time of normal operation shown in FIG. 4 and at the time of occurrence of a short circuit shown in FIG. As shown in FIG. 6, the difference between the detection value T1 of the first temperature detection element 3 and the detection value T2 of the second temperature detection element 5 is larger when a short circuit occurs than in the normal operation. Therefore, the occurrence of a short circuit in the semiconductor device 100 can be detected by examining the difference between the detection value T1 and the detection value T2.

  Conventionally, in a semiconductor device, a current detection element for detecting a short circuit of the semiconductor device has been installed separately from the temperature detection element. According to the temperature detection element of the present embodiment, it is possible to detect a short circuit of the semiconductor device, so that it is not necessary to install a current detection element to detect the short circuit. As a result, the structure of the semiconductor device can be simplified and the manufacturing process can be simplified.

  As described above, according to the present embodiment, when heat is generated inside the semiconductor substrate, it becomes easy to detect this heat. Further, since the temperature distribution in the depth direction of the semiconductor substrate can be detected, the position where heat is generated in the semiconductor substrate can be estimated based on the temperature distribution in the depth direction. Since the position where heat is generated can be estimated without performing cross-sectional observation, etc., it is possible to easily detect the position where heat is generated in the inspection process during manufacturing, and to feed back to the manufacturing process of the product to be manufactured thereafter It is.

  Note that a plurality of sets of first temperature detection elements and second temperature detection elements may be provided in the semiconductor device. For example, as shown in FIG. 7, in addition to the set of first temperature detection element 3 and second temperature detection element 5 shown in FIG. 1, a set of first temperature detection element 3a and second temperature detection element 5a, A set of first temperature detection element 3b and second temperature detection element 5b may be provided. In FIG. 7, the first temperature detection elements 3, 3a, 3b detect the temperature at a shallow position of the semiconductor substrate, and the second temperature detection elements 5, 5a, 5b detect the temperature at a deep position of the semiconductor substrate. The first electrodes 32, 52, 32a, 52a, 32b, and 52b are cathode pads, and the second electrodes 34, 54, 34a, 54a, 34b, and 54b are anode pads.

  Further, the pair of the first temperature detection element 3 and the second temperature detection element 5 can be installed in a region other than the central portion in the planar direction of the semiconductor substrate. In this case, it is preferable to install a pair of first temperature detection element 3 and second temperature detection element 5 at a position where the temperature distribution in the planar direction of the semiconductor substrate is the same. For example, as shown in FIG. 8, when the temperature distribution on the surface of the semiconductor substrate is represented by an elliptical isotherm centered on the center, a set of the same isotherm (for example, isotherm 8). It is preferable to install the first temperature detection element 3 and the second temperature detection element 5. By installing a pair of the first temperature detecting element 3 and the second temperature detecting element 5 in the isothermal region on the surface of the semiconductor substrate 10, the influence of the temperature distribution in the planar direction is reduced, and the depth of the semiconductor substrate 10 is increased. The temperature distribution in the vertical direction can be detected.

Further, as shown in FIG. 9, the first temperature sensing element 3 may be provided inside the deep P ⁺ layer 61 in a state surrounded by the main active region 1, or as shown in FIG. The first temperature detection element 3 may be formed inside a deep P ⁺ layer 63 as a peripheral breakdown voltage structure (FLR) of the semiconductor substrate 10. Further, as shown in FIG. 11, the trench depth of the first temperature sensing element 93 is the same depth as the trench gate 130 of the main active region 1, and the trench depth of the second temperature sensing element 95 is the main active region. It may be formed to a position deeper than one trench gate 130. Further, the second temperature detection element 95 may be formed inside the P ⁺ layer 65 that is deeper than the second temperature detection element 95. By installing the temperature detection element inside the deep P ⁺ layer, it is possible to suppress a decrease in the breakdown voltage of the semiconductor device.

Further, the temperature detecting element may not be the trench type temperature detecting element described in the first embodiment. For example, as shown in FIG. 12, an insulating film 47 may be provided on the surface of the semiconductor substrate 10, and the first temperature detection element 7 may be further provided on the surface. Further, as shown in FIG. 13, the first temperature detection element 7 may be installed on the surface of the deep P ⁺ layer 61. When the temperature detection element is provided on the surface of the semiconductor substrate, the installation position of the temperature detection element does not affect the decrease in the breakdown voltage of the semiconductor device.

  Further, in each of the above-described embodiments, the temperature detecting elements are arranged at two positions where the depth of the semiconductor substrate is different. However, the temperature is detected at three positions or three or more positions where the depth of the semiconductor substrate is different. You may make it arrange | position a detection element. By arranging the temperature detection elements in multiple stages in this way, the temperature distribution in the depth direction of the semiconductor substrate can be accurately estimated.

  The configuration of the trench bottom of the trench-type temperature detection element is not limited to the configuration shown in FIG. For example, as shown in FIG. 14, the N-type first semiconductor region 503 and the P-type second semiconductor region 505 may be adjacent to each other and formed at the same height. Further, as shown in FIGS. 15 and 16, two or more sets of diodes may be connected. 15 and 16, the N-type first semiconductor region 503 connected to the first electrode 523 forms a first PN junction with the P-type fourth semiconductor region 515, and the second electrode 525 The P-type second semiconductor region 505 to be connected forms a second PN junction with the N-type third semiconductor region 513. The third semiconductor region 515 and the fourth semiconductor region 513 are connected by a third electrode 527. The insulating films 507a and 507b isolate the first electrode 523, the second electrode 525, and the third electrode 527 from each other. The insulating film 557 isolates the first PN junction and the second PN junction. As a result, the first diode by the first PN junction and the second diode by the second PN junction are connected in series by the third electrode 527.

  As mentioned above, although the Example of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

DESCRIPTION OF SYMBOLS 1 Main active area 2 Temperature detection area 3, 3a, 3b, 7, 93 1st temperature detection element 5, 5a, 5b, 95 2nd temperature detection element 8 Isotherm 10 Semiconductor substrate 32, 32a, 32b, 52, 52a, 52b Cathode pads 34, 34a, 34b, 54, 54a, 54b Anode pads 41, 43, 45, 47 Insulating films 61, 63, 65 P ⁺ layer 100 Semiconductor device 101 Collector region 102 Buffer region 103 Drift region 104 Body region 105 Emitter Region 106 body contact region 130 trench gate 301, 501 trench 303, 503 first semiconductor region 305, 505 second semiconductor region 507, 507a, 507b, 557 insulator 513 fourth semiconductor region 515 third semiconductor region 523 first electrode 525 Second electrode 527 Third electrode

Claims (4)

A semiconductor substrate on which a main active region is formed;
A first temperature sensing element for sensing the temperature of the semiconductor substrate;
A second temperature detection element that detects a temperature at a position deeper in the semiconductor substrate than the first temperature detection element ;
First temperature sensing element and the second temperature sensing element is a semiconductor device which is characterized that you have provided an isothermal region of the semiconductor substrate surface. First temperature sensing element and the second temperature sensing element, the semiconductor device according to claim 1, wherein the planar direction of the position of the semiconductor substrate is adjacent. 3. The semiconductor device according to claim 1, wherein the first temperature detection element and the second temperature detection element are installed at a position that is a central portion in a planar direction of the semiconductor substrate. The second temperature sensing element is
A trench that is formed from the surface of the semiconductor substrate toward the inside, and an insulating film is formed on the inner wall surface thereof;
A first semiconductor region of a first conductivity type formed at the bottom of the trench;
A second semiconductor region of a second conductivity type formed at the bottom of the trench and in contact with the first semiconductor region;
A first electrode in contact with the first semiconductor region and not in contact with the second semiconductor region;
A second electrode in contact with the second semiconductor region and not in contact with the first semiconductor region;
An insulator separating the first electrode and the second electrode;
The semiconductor device according to any one of claims 1 to 3, characterized in that it comprises.

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