JP2014055803A - Inspection method and inspection apparatus of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection method of a semiconductor device which can identify a defective part of the semiconductor device without breaking the semiconductor device.SOLUTION: The inspection method of a semiconductor device includes: a first process of performing a first step of applying a pulse wave to each of a plurality of measurement positions through a coaxial probe 15 connected to each of the plurality of measurement positions of a diode 5 which is a semiconductor element, and a second step of measuring a reflection wave which is a pulse wave reflected from the diode 5 through the coaxial probe 15, sequentially for each of the plurality of measurement positions; and a second process of calculating a defective part 2 of the diode 5 on the basis of a plurality of reflection waves measured at the plurality of measurement positions.

Description

  The present invention relates to a semiconductor device inspection method and inspection apparatus for inspecting a defective portion of a semiconductor device.

  2. Description of the Related Art Conventionally, an inspection method using a TDR (Time Domain Reflectometry) apparatus is widely known as an inspection method when visual inspection is difficult. In measurement using a TDR device, a pulse wave is applied to an object to be measured, and the reflected wave of the applied pulse wave is measured, whereby the distance from the measurement point to the defective portion can be specified. There has been proposed an inspection method applied to inspection of defective soldering of a substrate or the like. (For example, Patent Document 1)

JP-A-9-61486

  In such a conventional inspection method, since a defective part can be specified one-dimensionally in the path from the measurement point to the inspection object, one-dimensional distance information from the measurement point to the defective part obtained from the TDR device is used. A defective part can be specified. However, when a TDR apparatus is used as a method for inspecting a semiconductor device, it is necessary to specify the position of the defective portion two-dimensionally on the plane of the semiconductor element, so that only one-dimensional distance information obtained from the TDR apparatus is defective. There was a problem that the location could not be specified. Therefore, in order to identify the defective part, it is necessary to perform light emission analysis, thermal analysis, overburst analysis, etc. For these analyses, it is necessary to destroy the semiconductor device, and the inspection apparatus is large and expensive. Therefore, it is difficult to specify a defective portion of the semiconductor device easily at low cost.

  The present invention has been made to solve the above-described problems, and provides a method for inspecting a semiconductor device that can easily identify a defective portion of the semiconductor device at low cost without destroying the semiconductor device. For the purpose.

  The inspection method for a semiconductor device according to the present invention includes a first step of applying a pulse wave for each of a plurality of measurement positions via a probe connected to a plurality of measurement positions of a semiconductor element; Based on the first step of measuring the reflected wave reflected from the semiconductor element in order for each of the plurality of measurement positions, and the plurality of reflected waves measured from the plurality of measurement positions, And a second step of calculating a defective portion of the semiconductor element.

  According to the method for inspecting a semiconductor device according to the present invention, the application of the pulse wave and the measurement of the reflected wave of the pulse wave reflected from the semiconductor element are performed at a plurality of measurement positions, so that the cost can be reduced without destroying the semiconductor device. Thus, the defective portion of the semiconductor device can be easily identified.

It is a block diagram which shows the structure of the inspection apparatus of the semiconductor device in Embodiment 1 of this invention. It is sectional drawing of the semiconductor device to which a part of inspection apparatus of the semiconductor device in Embodiment 1 of this invention was attached. It is the schematic which shows the diode which is a test object in Embodiment 1 of this invention. It is a top view of the semiconductor device which shows the measurement position in Embodiment 1 of this invention. It is a graph which shows the measurement waveform in Embodiment 1 of this invention. It is a flowchart of the measurement in each measurement point in Embodiment 1 of this invention. It is a flowchart of the semiconductor inspection method in Embodiment 1 of this invention. It is a top view which shows the calculation method of the proportionality constant in Embodiment 1 of this invention. It is the schematic which shows MOSFET which is a test object in Embodiment 1 of this invention. It is a block diagram which shows the semiconductor inspection apparatus in Embodiment 2 of this invention. It is sectional drawing of the semiconductor device to which a part of inspection apparatus of the semiconductor device in Embodiment 2 of this invention was attached.

Embodiment 1 FIG.
First, the configuration of the inspection apparatus used in the semiconductor device inspection method according to the first embodiment will be described. FIG. 1 is a block diagram showing a configuration of a semiconductor device inspection apparatus 100 according to the first embodiment. FIG. 2 is a cross-sectional view of the semiconductor device to which a part of the semiconductor device inspection apparatus according to the first embodiment is attached. is there. 3A is a top view of the diode 5 which is a semiconductor device to be inspected, FIG. 3B is a schematic cross-sectional view of the diode 5, and FIG. 3C is a bottom view of the diode 5. is there. In FIG. 2, the simplified illustration of the coaxial probe 15c among the coaxial probes 15 described below is omitted.

  1, a semiconductor device inspection apparatus 100 includes a high-frequency relay 14, a TDR device 10, a detection unit 13, three coaxial probes 15 (coaxial probes 15a, 15b, and 15c), and a metal bottom plate 20 illustrated in FIG. The metal side plate 21 and the high dielectric ceramic 19 are used. The high frequency relay 14 switches the connection between the TDR device 10 and each coaxial probe 15. The TDR device 10 outputs a pulse wave that is a stepped voltage (hereinafter simply referred to as “pulse wave”) and applies the pulse signal generator 11 to the semiconductor device 1, and a reflected wave of the pulse wave from the semiconductor device 1. It is comprised from the oscilloscope 11 which measures this. The reflected wave actually measured by the oscilloscope 11 is a combination of the reflected wave reflected from the semiconductor device 1 and the pulse wave output from the pulse signal generator 11. The reflected wave reflected from 1 may be measured. Based on the reflected wave measured by the oscilloscope 12, the detection unit 13 detects the presence or absence of a defect in the semiconductor device 1 and identifies the defective part.

  In FIG. 2, the semiconductor device 1 to be inspected can be, for example, a diode 5 having a vertical structure. The diode 5 has an anode electrode 3 and a cathode electrode 4, and is here arranged with the cathode electrode 4 at the bottom. The coaxial probes 15a, 15b, and 15c are respectively composed of coaxial center conductors 16a, 16b, and 16c, tip spring probes 17a, 17b, and 17c, and coaxial outer conductors 18a, 18b, and 18c (in FIG. 2, the coaxial probe 15c, The coaxial center conductor 16c, the tip spring probe 17c, and the coaxial outer conductor 18c are not shown. The coaxial center conductors 16a, 16b, and 16c are connected to the terminals of the high-frequency relay 14, respectively, and the tip spring probes 17a, 17b, and 17c are moved up and down by the springs to measure on the anode electrode 3 of the semiconductor element 1 to be inspected. Connected to a point. Further, the metal bottom plate 20 is disposed under the cathode electrode 4 of the semiconductor device 1 to be inspected, and the insulating high dielectric ceramic 19 is disposed so as to cover the anode electrode 3 and the metal bottom plate 20 of the semiconductor device 1. A metal side plate 21 is disposed between the metal bottom plate 20 and the high dielectric ceramic 19. Further, the coaxial outer conductors 18a, 18b, 18c are connected to the metal side plate 21 and form a ground together with the metal side plate 21 and the metal bottom plate 20, whereby the cathode electrode 4 is grounded.

  In FIG. 3, the diode 5 has an anode electrode 3 and a cathode electrode 4 on the upper and lower surfaces, respectively. In the diode 5, a defect such as a defect due to mixing of foreign matters or a short circuit failure due to electrostatic breakdown may occur at the time of manufacture. However, the anode electrode 3 or the cathode electrode 4 may be formed on the surface, and visually. It may be difficult to specify at which position on the plane of the diode 5 the defective portion exists. Hereinafter, a case where a short circuit failure due to electrostatic breakdown or the like has occurred at the position of a part of the defective portion 2 on the plane of the diode 5 will be described.

  Next, the operation of the semiconductor device inspection apparatus 100 will be described. FIG. 4 is a top view of the diode 5 to be inspected, and FIG. 5 is a graph showing a measured waveform measured by the oscilloscope 12.

  In FIG. 4, the position where the defect of the diode 5 occurs is defined as a defect location 2. Further, measurement is performed at three points A, B, and C on the anode electrode 3 of the diode 5, and the three coaxial probes 15a, 15b, and 15c are connected to the measurement points A, B, and C, respectively. Is done. Each measurement point is located at three of the four vertices of the diode 5, and a measurement point located at a vertex sandwiched between two of the three vertices is defined as point A. Here, when the coordinates are taken so that the horizontal direction in FIG. 4 is the X axis, the vertical direction is the Y axis, and the point A is the origin, each of the measurement points A, B, C, and the defective part 2 The coordinates are (0, 0), (0, y), (x, 0), and (Xa, Ya), respectively.

  In FIG. 5, the horizontal axis indicates time, and the vertical axis indicates voltage, and the waveform of the reflected wave measured from each measurement point is shown. The upper graph shows the reflected wave measured at point C, the middle graph shows the reflected wave measured at point B, and the lower graph shows the reflected wave measured at point A, represented by a solid line. The waveforms shown are the reflected wave waveforms v10, v20, v30 (hereinafter referred to as “non-defective products v10, v20, v30”) measured from the non-defective diodes, and the waveform indicated by the broken line is the position of the defective part 2 Are waveforms v1, v2, and v3 (hereinafter, referred to as “measurement waveforms v1, v2, and v3”) measured from the diode 5 having a defect. Furthermore, time t1 indicates the time when the pulse wave is output from the pulse signal generator 11, time t2 indicates the time when the measured waveform v2 measured at point B starts to deviate from the non-defective waveform v20, and time t3 indicates point A. The time when the measured waveform v1 measured in step 1 starts to deviate from the non-defective product waveform v10 is shown, and the time t4 shows the time when the measured waveform v3 measured at point C starts to deviate from the good product waveform v30. The difference between time t2 and time t1 is set as the divergence time b, the difference between time t3 and time t1 is set as the divergence time a, and the difference between time t4 and time t1 is set as the divergence time c.

  In FIG. 5, the measurement waveform at each time indicates the reflected wave reflected at a predetermined position from the measurement point. Here, when there is a short-circuit failure at the defective portion 2 as in the diode 5, the impedance at the defective portion 2 is smaller than the impedance at the corresponding position of the non-defective diode 5, so that reflection from the defective portion 2 occurs. Since the wave has a smaller waveform than the reflected wave from the same location of the non-defective product, it is possible to catch a failure as a waveform divergence. The time from the start of pulse wave output to the start of the divergence between the non-defective waveform and the measured waveform (hereinafter referred to as “divergence time”) is the time from when the pulse wave is reflected at the defective part 2 to return to the measurement part. It is proportional to the distance from the measurement location to the defective location 2. Therefore, by measuring the deviation time, the distance from the measurement point to the defective part 2 can be calculated. However, it is impossible to specify the position of the defective portion 2 only by measurement from one measurement point. Therefore, the defective portion 2 can be specified by measuring the reflected wave from a plurality of measurement points.

  Based on such a principle, the inspection apparatus 100 for a semiconductor device according to the first embodiment can measure from three points by providing three coaxial probes, and thus can identify the defective portion 2. . In the semiconductor device inspection apparatus 100, the non-defective product waveforms v10, v20, v30 are measured in advance, and the detection unit 13 stores them. Then, the detection unit 13 compares the measured waveforms v1, v2, and v3 from the respective measurement points measured by the oscilloscope 12 with the stored good product waveforms v10, v20, and v30, and calculates deviation times a, b, and c. The coordinates (Xa, Ya) of the defective portion 2 are obtained from the deviation times a, b, and c. Note that the coordinates of the defective portion 2 can be calculated by the following (Expression 1) and (Expression 2). Here, r is a proportional constant for converting the divergence time into distance (hereinafter referred to as “proportional constant r”).

  Next, a method for inspecting a semiconductor device according to the first embodiment will be described. FIG. 6 is a flowchart of measurement at each measurement point in the inspection method according to the first embodiment, and FIG. 7 is a flowchart of the entire inspection method according to the first embodiment.

  First, the measurement performed at each measurement point will be described with reference to FIG. In step S1, the high frequency relay 14 performs switching so that the terminal of the TDR device 10 is connected to the coaxial probe 15 connected to a predetermined measurement point. In step S2, the pulse signal generator 11 outputs a pulse wave and applies it to the semiconductor device 1 to be inspected. In step S3, the reflected wave is measured by the oscilloscope 12, and the measurement waveform measured by the detection unit 13 in step S4 is compared with the good product waveform measured in advance. In step S5, the presence or absence of a waveform divergence between the measured waveform and the non-defective waveform is detected. If there is a waveform divergence, the measurement is terminated, and if there is no waveform divergence, the process proceeds to step S6. In step S6, the detector 13 calculates a waveform divergence time from the measured waveform, and ends the measurement.

  Next, a semiconductor device inspection method according to the first embodiment will be described with reference to FIG. Here, the measurement is performed according to the flowchart shown in FIG. 6 in the order of the A point, the B point, and the C point, but the measurement may be performed in another order. In step S11, measurement is performed at point A, and in step S12, the presence or absence of abnormality is determined from the measurement result at point A. Here, if there is no abnormality, the process proceeds to step S21, where no abnormality is displayed in step S21, and the inspection is terminated. On the other hand, if there is an abnormality, the process proceeds to step S13 and measurement is continued. In step S13, the distance from point A to defective part 2 is calculated from the measurement result at point A. In step S14, measurement is performed at point B, and in step S15, the distance from point B to defective part 2 is calculated. Similarly, in step S16 and step S17, measurement at point C is performed, and the distance from point C to defective part 2 is calculated. In step S18, the coordinates of the defective part 2 are calculated based on (Equation 1) and (Equation 2) from the distance from each measurement point to the defective part 2. Thus, in step 19, the coordinate position of the defective part 2 is displayed, and the measurement is finished.

In addition, immediately after the measurement at each measurement point, the distance from each measurement point to the defective part 2 is calculated. However, the measurement waveform at each measurement point or the waveform deviation time is stored, and the measurement at the C point is performed. It is good also as calculating after performing. In the above description, the waveform divergence time is calculated in the measurement at each measurement point. However, the waveform divergence time at each measurement point and the measurement waveform are stored after the measurement at the C point is stored. The distance from each measurement point to the defective part 2 may be calculated.

  Here, in the measurement at each measurement point, the distance from the measurement point to the defective portion is calculated by (Equation 1) and (Equation 2). In this case, it is necessary to obtain the proportionality constant r. Although the proportionality constant r varies depending on the dielectric constant inside the semiconductor element, the dielectric constant varies depending on the type and structure of the semiconductor device 1, and therefore a method for obtaining the proportionality constant r in advance will be described below. FIG. 8 illustrates a method for calculating the proportional constant r. In FIG. 8, first, the adjustment short-circuit needle 22 is brought into contact with a point where the distance from the measurement point is known, for example, a diagonal position of the point A. Next, a pulse wave is output from the TDR device 10 in a state where the adjustment short-circuit needle 22 is in contact, and the reflected wave is measured. Then, the proportional constant r can be obtained by comparing the measured reflected wave with the non-defective waveform and calculating the deviation time. It is sufficient to measure the reflected wave once at any one of points A, B, and C. However, the proportional constant r is obtained by measuring at a plurality of measurement points in consideration of the variation for each measurement. It is good as well. Further, although the proportionality constant r is sufficiently calculated once for each type of product to be inspected, it may be performed every time even for the same type of product in consideration of the variation between the same type of products.

  According to the semiconductor device inspection method according to the first embodiment, the defective portion of the semiconductor device can be specified on the plane of the semiconductor element without destroying the semiconductor device by the process as described above.

  Further, the distance resolution of the semiconductor device inspection apparatus 100 is determined by the time resolution, the high-frequency characteristics, and the rising speed of the waveform. The current measuring instrument has a time resolution of about 1 ps and the rising of the waveform is about 15 ps. Is theoretically converted to a time resolution of about 0.15 mm for a line in the air, but it is about 0.5 mm depending on the performance of a high-frequency transmission line and the voltage measurement system that captures voltage divergence. Distance accuracy is the limit. However, in the present invention, since the electrode of the semiconductor device 1 to be inspected is covered with the high dielectric ceramic 19, the propagation speed of the reflected wave decreases in proportion to the 1/2 power of the relative dielectric constant of the high dielectric ceramic 19. To do. As a result, it is possible to improve the distance resolution of the TDR device without improving the time resolution or the like of the measuring instrument. For example, when the high dielectric ceramic 3 having a relative dielectric constant of 100 to 1000 is used, the propagation speed of the reflected wave is reduced to about 1/5 to 1/15 times, so the distance resolution of the inspection apparatus 100 of the semiconductor device is It improves about 5 to 15 times.

  In the above description, the case where measurement is performed from three points on the anode electrode 3 with the cathode electrode 4 at the bottom has been described. In addition, three points on the cathode electrode 4 with the anode electrode 3 at the bottom have been described. It is desirable to perform measurement from above and to perform measurement on both electrodes. When measurement is performed on the cathode electrode 4 with the anode electrode 3 at the bottom, the measurement is performed in the same manner as when measurement is performed on the anode electrode 3 with the anode electrode 3 grounded. Thereby, compared with the case where it measures from only one electrode, inspection accuracy can be improved. Here, when the cathode electrode 4 is grounded and measurement is performed on the anode electrode 3, a pulse wave is applied in the forward direction of the diode 5, so that the voltage level of the pulse wave is the rising voltage of the diode 5 (“threshold value”). Also referred to as “voltage”.) If it is larger, the current flowing in the forward direction may increase, making measurement difficult. Therefore, when the measurement is performed on the anode electrode 3 with the cathode electrode 4 grounded, the measurement can be performed by setting the voltage level of the pulse wave to be lower than the rising voltage of the diode 5, for example, about 100 mV.

In the present embodiment, the case where the diode 5 is measured as the semiconductor device 1 has been described. However, the present invention is not limited to this, and the position of the defective portion is specified for other semiconductor devices such as MOSFETs and IGBTs. Inspection can be performed. Hereinafter, a case where the inspection is performed on the MOSFET 9 will be described with reference to FIG. 9A is a top view of the MOSFET 9, FIG. 9B is a schematic cross-sectional view of the MOSFET 9, and FIG. 9C is a bottom view of the MOSFET 9. In FIG. 9, a MOSFET 9 has a source electrode 7 and a gate electrode 6 formed on the upper surface and a drain electrode 8 formed on the lower surface. Therefore, in the case of MOSFET 9, there are the following four measurement methods, so it is desirable to perform all four measurement methods, and the inspection accuracy is improved as compared with the case where only a single measurement method is used. be able to. In particular, since there are defects that appear only when the MOSFET is in an ON state or an OFF state, it is more desirable to perform measurement in both the ON state and the OFF state.
・ Measure the source electrode 7, ground the drain electrode 8, open the gate electrode 6 (OFF state)
・ Measure the drain electrode 8, ground the source electrode 7, open the gate electrode 6 (OFF state)
・ Measure the source electrode 7, ground the drain electrode 8, apply voltage to the gate electrode 6 (ON state)
・ Drain electrode 8 is measured, source electrode 7 is grounded, and voltage is applied to gate electrode 6 (ON state)

  In this embodiment, measurement is performed from three measurement points. However, if measurement is performed from at least two measurement points, a defective portion can be specified. However, when there are two measurement points, there are two points having the same distance from each measurement point depending on the position of the measurement point, so it is necessary to pay attention to the position of the measurement point. Specifically, if the measurement is performed from two points on the same side of the semiconductor device, the defective portion can be specified as one point. Further, when measurement is performed from three or more measurement points, it is possible to calculate the proportional constant r and specify the position of the defective portion without calculating the proportional constant r in advance. And by reducing the number of measurement points, the time required for one inspection can be shortened, but by increasing the number of measurement points, it is possible to improve the accuracy of identifying defective parts, such as products, etc. It is possible to carry out an inspection by determining an appropriate number of measurement points in accordance with.

Embodiment 2. FIG.
In the first embodiment, the semiconductor device inspection apparatus including the plurality of coaxial probes 15 and the high frequency relay 14 is used. However, the present invention is not limited thereto, and the semiconductor device inspection apparatus including the movable probe 26 is used. It is good also as using. Therefore, as a second embodiment, a case where the semiconductor device inspection apparatus 101 including the movable probe 26 is used will be described. Since the second embodiment is different from the first embodiment in that the movable probe 26 is used, the difference will be described, and description of the same or corresponding parts will be omitted.

  FIG. 10 is a block diagram showing a configuration of the semiconductor device inspection apparatus 101 according to the second embodiment. FIG. 11 is a cross-sectional view of the semiconductor device to which a part of the semiconductor device inspection apparatus according to the second embodiment is attached. It is. 10 and 11, the same reference numerals as those in FIGS. 1 to 9 denote the same or corresponding components, and the description thereof is omitted.

  In FIG. 10, a semiconductor device inspection apparatus 101 includes a movable probe 26, a TDR apparatus 10, and a detection unit 13. The movable probe 26 can be connected to each measurement point of the semiconductor device 1 by operating. The TDR device 10 includes a pulse signal generator 11 and an oscilloscope 12, and the pulse signal generator 11 passes through the movable probe 26. Then, a pulse wave is applied to the semiconductor device 1 and the oscilloscope 12 measures a reflected wave from the semiconductor device 1. And the detection part 13 specifies the defect location 2 from the measured reflected wave.

  In FIG. 11, the movable probe 26 includes an x-axis direction stage 23, a y-axis direction stage 24, a z-axis direction stage 25, and a single coaxial probe 15d. The movable probe 26 can be operated in all three axial directions by the x-axis direction stage 23, the y-axis direction stage 24, and the z-axis direction stage 25, whereby the coaxial probe 15 is sequentially placed at a predetermined measurement point. Can be connected. The coaxial probe 15d includes a coaxial center conductor 16d, a tip spring probe 17d, and a coaxial outer conductor 18d. However, a general high-frequency probe may be used instead of the tip spring probe 17d.

  Further, a metal side plate 21 is installed on the side surface side of the semiconductor device 1, a metal bottom plate 20 is installed on the lower surface electrode of the semiconductor device 1, and a high dielectric ceramic 19 is further provided on the lower surface side of the metal bottom plate 20. The metal side plate 21 and the metal bottom plate 20 form a ground, and the lower surface electrode of the semiconductor device 1 is grounded.

  With such a configuration, it is possible to perform measurement at a plurality of measurement points without providing a plurality of coaxial probes 15, and it is possible to specify a defective portion. In particular, since it is possible to flexibly measure semiconductor devices having different shapes with the same inspection device, it is possible to easily identify a defective portion even when the shapes of the semiconductor devices are different.

  Note that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be modified or omitted as appropriate.

DESCRIPTION OF SYMBOLS 1 Semiconductor device 2 Defect location 3 Anode electrode 4 Cathode electrode 5 Diode 6 Gate electrode 7 Source electrode 8 Drain electrode 9 MOSFET
DESCRIPTION OF SYMBOLS 10 TDR apparatus 11 Pulse signal generator 12 Oscilloscope 13 Detection part 14 High frequency relay 15a, 15b, 15c, 15d Coaxial probe 16a, 16b, 16c, 16d Coaxial center conductor 17a, 17b, 17c, 17d Tip spring probe 18a, 18b, 18c , 18d Coaxial outer conductor 19 High dielectric ceramic 20 Metal bottom plate 21 Metal side plate 22 Adjusting short-circuit needle 23 X-axis direction stage 24 Y-axis direction stage 25 Z-axis direction stage 26 Movable probe 100, 101 Semiconductor device inspection device

Claims (8)

A first step of applying a pulse wave to each of the plurality of measurement positions via a probe connected to a plurality of measurement positions of the semiconductor element; and a reflection in which the pulse wave is reflected from the semiconductor element via the probe A first step of sequentially performing a second step of measuring a wave for each of the plurality of measurement positions;
A second step of calculating a defective portion of the semiconductor element based on the plurality of reflected waves measured from the plurality of measurement positions;
A method for inspecting a semiconductor device comprising: The second step is performed by comparing the reflected wave measured in advance in the non-defective semiconductor device with the reflected wave measured in the first step.
2. The method for inspecting a semiconductor device according to claim 1, wherein: In the first step, after the second step at the first measurement position among the plurality of measurement positions, the presence / absence of a defect in the semiconductor element is determined based on the reflected wave measured in the second step. A third step of detecting,
If it is detected in the third step that the semiconductor element is not defective, the inspection is terminated.
The method for inspecting a semiconductor device according to claim 2. The first step is performed in a state where the lower electrode of the semiconductor element is covered with a grounded metal plate, and the upper electrode of the semiconductor element and the metal plate are covered with an insulating dielectric.
4. The method for inspecting a semiconductor device according to claim 1, wherein: A connection part connectable to a plurality of measurement positions of a semiconductor element; and a pulse signal generator that applies a pulse wave to the measurement position of the semiconductor element connected by the connection part;
A measurement unit for measuring a reflected wave reflected from the semiconductor element by the pulse wave;
Based on the reflected wave measured by the measurement unit from the plurality of measurement positions, a detection unit that calculates a defective portion of the semiconductor element,
An inspection apparatus for a semiconductor device, comprising: A metal plate that covers the lower electrode of the semiconductor element and is grounded;
An insulating dielectric covering the upper electrode of the semiconductor element and the metal plate;
The semiconductor device inspection apparatus according to claim 5, further comprising: The connecting portion is
Two or more probes respectively connected to the plurality of measurement positions;
A switching unit that switches connection between the pulse signal generator and the measurement unit and any one of the two or more probes;
The semiconductor device inspection apparatus according to claim 5, further comprising: The connecting portion is
Probes connected to the plurality of measurement positions;
A movable part capable of moving the probe in a plane direction parallel to a plane on which the measurement position of the semiconductor element exists and a vertical direction perpendicular to the plane direction;
The semiconductor device inspection apparatus according to claim 5, further comprising:

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