JP6602519B1 - Semiconductor device, deterioration diagnosis device for semiconductor device, and deterioration diagnosis method for semiconductor device - Google Patents

Abstract

A semiconductor device (1) in which a semiconductor chip (2) mounted via an insulating substrate (3) electrode (4) is sealed with an insulating resin (8), facing the end (2a) of the semiconductor chip In the upper insulating resin (8), there is provided an electrode part (13) which is arranged apart from the semiconductor chip (2) and can apply a voltage from the outside. After the application, a reverse voltage is applied to the semiconductor chip, and a leak current flowing through the semiconductor chip is measured. Due to the influence of the electric field from the electrode section (13), the breakdown voltage of the semiconductor chip (2) is reduced and the leakage current is increased, so that the sensitivity of deterioration diagnosis is improved.

Description

  The present application relates to a semiconductor device, a deterioration diagnosis device for a semiconductor device, and a deterioration diagnosis method for a semiconductor device.

  In a semiconductor device such as a semiconductor power module, by performing deterioration diagnosis or life prediction, it is possible to know a guideline for replacing the semiconductor device. Therefore, by replacing the semiconductor device before the failure occurs, it is possible to prevent an accident due to the failure of the semiconductor device in the device in which the semiconductor device is incorporated.

  For example, a conventional semiconductor device deterioration diagnosis apparatus detects a leakage current when a reverse voltage is applied to a semiconductor device to be diagnosed, and evaluates the degree of deterioration from the result (see, for example, Patent Document 1). .

  On the other hand, there is known a test apparatus that measures the variation in breakdown voltage by applying an electric field from the outside of the semiconductor device (for example, see Patent Document 2).

JP 2003-294807 A JP 2010-66250 A

  However, in the method of Patent Document 1, since the reverse voltage is directly applied to the semiconductor device, the fluctuation amount of the leakage current is small unless the deterioration is advanced. In addition, since it is susceptible to environmental fluctuations such as temperature during measurement, there is a problem that it is difficult to determine whether small fluctuations in leakage current are caused by deterioration.

  Therefore, if the withstand voltage test method disclosed in Patent Document 2 is used, an electric field can be applied to the semiconductor device to be diagnosed from the outside to lower the withstand voltage of the semiconductor device, and it is expected that deterioration diagnosis can be performed.

  The present application discloses a technique for solving the above-described problems, and by applying a voltage from the outside to the semiconductor device to be diagnosed, the breakdown voltage of the semiconductor device is lowered, and a leakage current is detected. An object of the present invention is to provide a semiconductor device capable of performing a deterioration diagnosis of a semiconductor device, a deterioration diagnosis device for a semiconductor device, and a deterioration diagnosis method.

A semiconductor device disclosed in the present application includes a semiconductor chip mounted via an insulating substrate and an electrode on the insulating substrate, and the insulating substrate and the semiconductor chip are sealed with an insulating resin. In the upper insulating resin facing the end portion of the semiconductor chip, the semiconductor chip is provided so as to be separated from the semiconductor chip and electrically insulated , and provided with an electrode portion to which a voltage can be applied from the outside.

A semiconductor device diagnostic device disclosed in the present application is a semiconductor device diagnostic device that performs a deterioration diagnosis of a semiconductor device including the above-described electrode unit, and includes a power source that applies a voltage to the electrode unit, and a semiconductor chip. A power source for applying a voltage; and an ammeter for measuring a current flowing through the semiconductor chip.

  A method for diagnosing a semiconductor device disclosed in the present application is a method for diagnosing deterioration of a semiconductor device including the above-described electrode unit, the first step of applying a voltage to the electrode unit, and the electrode A second step of applying a reverse voltage to the semiconductor chip in a state where a voltage is applied to the part, a third step of measuring a current flowing through the semiconductor chip, a measured current, and a reference current acquired in advance. And a fourth step of performing deterioration diagnosis.

  According to the present application, an electrode portion is provided opposite to an end portion of a semiconductor chip in a semiconductor device, and a voltage is applied to the electrode portion from the outside, whereby the withstand voltage of the semiconductor device is temporarily reduced and leakage current is reduced. Since it is easy to detect, the sensitivity of the deterioration diagnosis of the semiconductor device is improved.

1 is a diagram illustrating a configuration of a semiconductor device and a deterioration diagnosis device for a semiconductor device according to a first embodiment. 1 is a perspective view showing a partial configuration of a semiconductor device according to a first embodiment. 3 is a flowchart showing a degradation diagnosis method for a semiconductor device according to the first embodiment. It is a figure for demonstrating the degradation fluctuation | variation in the voltage-current characteristic of a semiconductor chip. It is a figure for demonstrating the influence of the applied electric field in the voltage-current characteristic of a semiconductor chip. FIG. 4 is a diagram showing a configuration of a semiconductor device according to a second embodiment. FIG. 10 is a diagram showing an electric field analysis model of a semiconductor device as a comparative example according to the second embodiment. 6 is a diagram showing an electric field analysis model of a semiconductor device according to a second embodiment. FIG. FIG. 6 is a diagram showing a configuration of a semiconductor device according to a third embodiment. 6 is a diagram showing an electric field analysis model of a semiconductor device according to a third embodiment. FIG. FIG. 10 is a diagram showing another configuration of the semiconductor device according to the third embodiment. FIG. 6 is a diagram showing a configuration of a semiconductor device according to a fourth embodiment. FIG. 6 is a diagram showing a configuration of a semiconductor device according to a fourth embodiment. FIG. 10 is a diagram showing a configuration of a semiconductor device according to a fifth embodiment. FIG. 10 is a perspective view showing a partial configuration of a semiconductor device according to a fifth embodiment. FIG. 10 is a perspective view showing another partial configuration of the semiconductor device according to the fifth embodiment. FIG. 10 is a top view showing another partial configuration of the semiconductor device according to the fifth embodiment. FIG. 10 is a perspective view showing a partial configuration of a semiconductor device according to a sixth embodiment. FIG. 10 is a top view showing a partial configuration of a semiconductor device according to a sixth embodiment. It is a figure which shows the structure of the deterioration diagnostic apparatus of the semiconductor device which concerns on Embodiment 7. FIG. FIG. 10 is a diagram showing another configuration of a semiconductor device degradation diagnosis apparatus according to a seventh embodiment. It is a figure which shows another structure of the deterioration diagnostic apparatus of the semiconductor device which concerns on Embodiment 7. FIG. It is a figure which shows another structure of the deterioration diagnostic apparatus of the semiconductor device which concerns on Embodiment 7. FIG.

  Hereinafter, embodiments of a semiconductor device, a deterioration diagnosis device for a semiconductor device, and a deterioration diagnosis method will be described with reference to the drawings. In addition, in each figure, the same code | symbol shall show the part which is the same or it corresponds.

Embodiment 1 FIG.
The semiconductor device according to the first embodiment will be described below. FIG. 1 is a diagram illustrating an example of a configuration of a semiconductor device and a deterioration diagnosis device for a semiconductor device according to the first embodiment. In FIG. 1, a semiconductor device 1 includes an insulating substrate 3 made of a ceramic such as aluminum nitride or alumina, a semiconductor chip 2 solder-bonded via a substrate upper electrode 4 provided on the insulating substrate 3, and an insulating substrate. 3 has a heat sink 6 soldered via a substrate lower electrode 5 provided at the lower part of 3 and an electrode part 13 for applying an external electric field above the end part 2a of the semiconductor chip, It is housed in a case 7 and sealed with an insulating resin 8.

The semiconductor chip 2 is a chip made of a power semiconductor element such as an IGBT (Insulated Gate Bipolar Transistor) or a MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The insulating substrate 3 is not limited to ceramic, and an insulating resin substrate such as an epoxy resin may be used. The heat radiating plate 6 is made of a material having high thermal conductivity such as copper or aluminum in order to release heat from the semiconductor chip 2 to the outside. For the insulating resin 8 that seals the inside of the case 7, an insulating resin such as silicone gel or epoxy resin is used. Since a high voltage is applied to the semiconductor chip 2 and the substrate upper electrode 4, the periphery is covered with an insulating resin 8 to maintain insulation. The semiconductor chip 2 has electrodes (emitter electrode, collector electrode) for applying a voltage to the upper and lower surfaces thereof. By applying a voltage from the power supply 10 between the substrate upper electrode 4 and the upper surface electrode 9 of the semiconductor chip 2, a voltage is applied to the semiconductor chip 2 to operate it. Note that the lower surface electrode of the semiconductor chip 2 is not shown. In addition, the electrode portion 13 for applying an external electric field is disposed in an insulating resin above the end portion 2a of the semiconductor chip 2 so as to be spaced apart from components such as the semiconductor chip 2 and the like.

  Next, a deterioration diagnosis apparatus for the semiconductor device 1 will be described. A DC power supply 14 is connected to the electrode portion 13 in the semiconductor device 1 through a wiring 131. During the operation of the deterioration diagnosis device, the rated voltage of the semiconductor chip is applied from the power supply 10 so that the reverse voltage is applied to the semiconductor chip 2 inside the semiconductor device 1, and the leakage current flowing through the semiconductor chip 2 is reduced to the semiconductor chip 2. It measures with the ammeter 11 provided in the wiring connected to. By applying a voltage to the electrode portion 13 from the DC power supply 14, an electric field is applied from the electrode portion 13 to the end portion 2a of the semiconductor chip. The voltage applied to the electrode part 13 at this time is kept below the dielectric breakdown voltage of the insulating resin 8.

  Here, the position of the electrode part 13 in the semiconductor device 1 will be described. FIG. 2 is a perspective view showing the positional relationship between the semiconductor chip 2 and the electrode portion 13 in the semiconductor device 1. As shown in FIG. 2, the electrode portion 13 is provided above the end portion 2 a of the semiconductor chip 2. The electrode portion 13 is installed so as to be embedded in the insulating resin 8, and is electrically insulated from surrounding electrodes such as the upper surface electrode 9, and is electrically connected to the outside of the semiconductor device 1. Wiring 131 is provided.

Next, the deterioration diagnosis method for the semiconductor device 1 according to the first embodiment will be described with reference to a flowchart. FIG. 3 is a flowchart showing a method for diagnosing deterioration of a semiconductor device.
First, in step S <b> 1, a DC voltage is applied from the DC power supply 14 to the electrode unit 13 in the semiconductor device 1.
Next, in step S <b> 2, a test voltage for performing deterioration diagnosis is applied to the semiconductor chip 2. As the test voltage, a reverse voltage is applied to the semiconductor chip.
In step S <b> 3, the leak current flowing through the semiconductor chip 2 is measured by the ammeter 11.
After measuring the leakage current, application of voltage to the electrode unit 13 and the semiconductor chip 2 is stopped in step S4.
In step S5, a normal leakage current measured and acquired in advance is compared with the measured leakage current, and deterioration diagnosis is performed. In the deterioration diagnosis, the degree of deterioration is diagnosed by the amount of increase in leakage current from the normal time.

The effect of applying an electric field to the end 2a of the semiconductor chip 2 will be described.
4A and 4B are diagrams showing voltage-current characteristics of the semiconductor chip. In FIG. 4A, the leakage current increases linearly with respect to the voltage under normal conditions. When the semiconductor chip is deteriorated, the leakage current increases sharply as the voltage increases, deviating from the linear shape. In this embodiment, the deterioration diagnosis is performed based on the difference in leakage current from the normal time. When the test voltage is V1 in the figure, the difference in leakage current between the deterioration time and the normal time, that is, the leakage current at the time of deterioration. The increment is small and the deterioration state cannot be determined. When the test voltage is increased to V2, the difference between the leakage currents of both increases, and deterioration diagnosis can be performed. However, an increase in test voltage can cause destruction or deterioration of the semiconductor chip. Furthermore, the test voltage cannot exceed the rated voltage of the semiconductor chip, and there is a restriction on the setting of the test voltage.

  By the way, although the semiconductor chip is insulated by an internal depletion layer, a withstand voltage is reduced due to a phenomenon such as an internal depletion layer contracting due to an external electric field, and an increase in leakage current is caused. FIG. 4B is a diagram in which an external electric field generated at the time of deterioration diagnosis is superimposed on the semiconductor chip at the time of deterioration shown in FIG. 4A. When an external electric field is applied, the withstand voltage is temporarily reduced, and the leakage current increases as indicated by arrows in the figure. As a result, even if the test voltage equal to or lower than the rated voltage is V1, it is possible to detect the amount of increase in leakage current from the normal time and to perform deterioration diagnosis.

  In the above description, the leakage diagnosis at the normal time is used as the reference current, and the deterioration diagnosis is performed with the increased amount of the difference. However, when the initial state of the semiconductor chip can be regarded as the normal state, this initial state leakage current is used. You may make it judge by the difference of leak current by making an electric current into a reference current. In this case, if the leakage current is measured periodically and recorded for every predetermined operating time of the semiconductor device 1, the history of deterioration or the prediction of deterioration can be made.

As described above, according to the first embodiment, the semiconductor device 1 is configured by disposing the electrode portion 13 inside the semiconductor device 1 and above the end portion 2a of the semiconductor chip 2. 13 is configured so that a voltage is applied by the DC power supply 14 connected to the wiring 13 via the wiring 131. Therefore, when the semiconductor device 1 is diagnosed for deterioration, an electric field is applied to the semiconductor chip 2 from the outside to reduce the withstand voltage. The leakage current can be increased and the leakage current can be easily detected without increasing the test voltage applied to the semiconductor chip 2. As a result, the sensitivity of deterioration diagnosis can be improved, and the deterioration state can be determined from the leakage current even in a semiconductor chip where deterioration has not progressed.
In addition, since the electrode portion 13 is separated from other electrodes above the end portion 2 a of the semiconductor chip 2 in the semiconductor device 1 and is insulated and embedded in the insulating resin 8, other than the end portion 2 a of the semiconductor chip 2. There is no influence of an external electric field.

Embodiment 2. FIG.
The configuration of the semiconductor device according to the second embodiment will be described below.
FIG. 5 is a diagram showing a configuration of the semiconductor device according to the second embodiment. Although the electrode part 13 is disposed above the end part 2a of the semiconductor chip 2 in the insulating resin 8 of the semiconductor device 1 as in the first embodiment, the electrode part 13 is covered with the insulating film 15. This is different from the first embodiment. In the first embodiment, the electrode portion 13 is disposed above the end portion 2a of the semiconductor chip 2 and is separated from other electrodes. However, when the electrode portion 13 is close to other electrodes and wiring members (wires, etc.), It is important to ensure insulation between the electrode and wiring member and the electrode portion 13. Therefore, in the second embodiment, an example will be described in which the electrode portion 13 is covered with an insulating film 15 having a volume resistivity higher than that of the insulating resin 8 to ensure insulation from the surroundings.

  When the electrode part 13 is covered with the insulating film 15 and the volume resistivity of the insulating film 15 is larger than the volume resistivity of the surrounding insulating resin 8, a series voltage is applied when a DC voltage is applied to the electrode part 13. Due to the sharing relationship, the potential difference is biased toward the high resistance side, and the potential difference on the low resistance side is reduced. As a result, the electric field on the low resistance side is lowered. That is, the electric field on the insulating resin 8 side is weakened, and the effect of lowering the breakdown voltage of the semiconductor chip 2 is reduced by applying a voltage to the electrode portion 13. Therefore, in the second embodiment, as shown in FIG. 5, the insulating film 15 is not covered in a region below the electrode portion 13 and facing the end portion 2 a of the semiconductor chip 2. With this configuration, when a voltage is applied to the electrode portion 13, a decrease in the electric field on the insulating resin 8 side is suppressed, and an effect of reducing the breakdown voltage of the semiconductor chip 2 can be achieved.

  Next, the result of electric field analysis when the electrode portion 13 is covered with the insulating film 15 will be described. 6A and 6B are diagrams illustrating an electric field analysis model of the semiconductor device according to the second embodiment. 6A shows a comparative example in which the semiconductor chip 2 side of the electrode portion 13 is entirely covered with the insulating film 15, and FIG. 6B shows the electrode portion 13 that does not cover the insulating film 15 in the region facing the end portion 2a of the semiconductor chip. An electric field analysis model is shown. 6A and 6B, the vicinity of the electrode portion 13 is axisymmetric with respect to the center dotted line, the electrode portion 13 is a cylinder having a diameter d, the voltage HV is applied to the electrode portion 13, and the end portion 2a of the semiconductor chip. The height from the upper surface to the electrode portion 13 is indicated by h, the thickness of the insulating film 15 is indicated by t, and the region not covered with the insulating film 15 is indicated by a region having a diameter a. A position immediately below the electrode portion 13 on the end portion 2a of the semiconductor chip is A.

In this electric field analysis model, the insulating resin 8 as the sealing material is, for example, silicone gel, the volume resistivity is 1 × 10 ¹³ Ωm, the insulating film 15 is, for example, polyimide, the volume resistivity is 1 × 10 ¹⁴ Ωm, The diameter d of 13 is 3 mm, the height h is 2 mm, the thickness t of the insulating film 15 is 0.1 mm, the diameter a of the hole in the insulating film below the electrode portion 13 is 1 mm, and the electric field at point A when a DC voltage is applied is The analysis was performed using a DC field.
As a result, the electric field at point A in FIG. 6B was about 13% higher than the electric field at point A in FIG. 6A.
Further, in FIG. 6B, when the diameter a of the hole of the insulating film below the electrode part 13 is 3 mm, that is, the insulating film 15 is not covered at the lower part of the electrode part 13 and the insulating film 15 is covered only on the side surface of the electrode part 13. In this case, the electric field at point A in FIG. 6B was about 55% higher than that in the entire surface covering state in FIG. 6A.

When the electrode part 13 is covered with the insulating film 15 having a volume resistivity higher than that of the insulating resin 8, the voltage drop is biased toward the insulating film 15, and the electric field at other locations tends to decrease. For this reason, the fall of the electric field given to the semiconductor chip 2 can be suppressed when the region facing the end 2a of the semiconductor chip is not covered with the insulating film 15.
By covering the electrode portion 13 with the insulating film 15 having a volume resistivity higher than that of the insulating resin 8, it is possible to suppress the influence of the electric field on the electrode and the wiring member around the end portion 2a of the semiconductor chip. Furthermore, since the effect of lowering the breakdown voltage of the semiconductor chip 2 is suppressed when the insulating film 15 is coated on the part of the electrode part 13 that faces the end part 2a of the semiconductor chip, the end part 2a of the semiconductor chip and its surrounding electrodes and Depending on the positional relationship with the wiring member, the covering area of the insulating film 15 on the region facing the end 2a of the semiconductor chip is changed, and the covering of the insulating film 15 on the region facing the end 2a of the semiconductor chip is limited. It is good to do.

  As described above, according to the second embodiment, at least the side surface portion of the electrode portion 13 disposed inside the semiconductor device 1 and above the end portion 2 a of the semiconductor chip 2 has a volume larger than that of the insulating resin 8. Since the insulating film 15 having a high resistivity is covered and at least a part of the surface facing the end 2 of the semiconductor chip 2 is not covered with the insulating film 15, an electric field is applied to the semiconductor chip 2 from the outside. However, the influence of the electric field on the electrodes and wiring members around the end 2a of the semiconductor chip or around the electrode part 13 is suppressed, insulation is maintained, and a highly sensitive deterioration diagnosis can be performed.

Embodiment 3 FIG.
The configuration of the semiconductor device according to the third embodiment will be described below.
FIG. 7 is a diagram showing a configuration of the semiconductor device according to the third embodiment. Although the electrode part 13 is arranged above the end part 2a of the semiconductor chip 2 in the insulating resin 8 of the semiconductor device 1 as in the first and second embodiments, the electrode part 13 is covered with the insulating film 16. This is different from the first and second embodiments.
As described in the second embodiment, the electric field applied from the electrode portion 13 is affected by the volume resistivity of the surrounding insulating material. In the structure of the semiconductor device 1 shown in the third embodiment, as shown in FIG. 7, the insulating film 16 is covered under the electrode portion 13, and the volume resistivity of the insulating film 16 is the volume resistivity of the insulating resin 8. Lower than. With this structure, the electric field between the lower part of the electrode part 13 covered with the insulating film 16 and the end part 2a of the semiconductor chip facing the surface is emphasized.

Next, the result of the electric field analysis when the lower part of the electrode part 13 is covered with the insulating film 16 will be described. FIG. 8 is a diagram showing an electric field analysis model of the semiconductor device according to the third embodiment. The basic configuration of the model is the same as that described in FIGS. 6A and 6B of the second embodiment. In FIG. 8, the thickness of the insulating film 16 is t.
In the field analysis model of FIG. 8, the insulation volume resistivity of the resin 8 as e.g. silicone gel 1 × 10 ¹³ [Omega] m, a volume resistivity of a 1 × 10 ¹² Ωm an insulating film 16 as, for example, an epoxy resin, the diameter of the electrode portions 13 d is 3 mm, height h is 2 mm, the insulating film 16 is covered only on the lower surface of the electrode, and the thickness t is 0.1 mm. The electric field at point A in FIG. 8 and the electric field at point A when the insulating film 16 is not covered with the insulating film in FIG. 8 were compared by electric field analysis of a DC field. As a result, the electric field in the case of FIG. 8 covered with the insulating film 16 was about 6% higher than the electric field in the case where the insulating film was not covered.

7 shows an example in which the insulating film 16 is provided from the lower part of the electrode portion 13 to a part of the side surface, but the insulating film 16 is provided only on the side surface of the electrode portion 13 as shown in FIG. Also good. Using the same materials and parameters (physical properties) as those in the electric field analysis model described in FIG. 8, the electric field at point A is compared when the insulating film thickness is 0.1 mm and when the insulating film 16 is not covered in FIG. did. As a result, the electrode portion 13 provided with the insulating film 16 having a thickness of 0.1 mm on the side surface has a higher electric field by about 2%.
Further, the insulating film 16 may be provided on both the lower surface and the side surface of the electrode portion 13. The electric field at point A when the insulating film 16 having a thickness of 0.1 mm is provided on both the lower surface and the side surface of the electrode portion 13 is about 8% higher than the electric field at point A when the insulating film is not covered. became.
From the above, the insulating film 16 may be covered on the entire surface of the electrode portion 13, but the insulating film 16 is lower than the volume resistivity of the insulating resin 8, and the electric field from the voltage applied to the electrode portion 13 is reduced. In order to act so as to emphasize the influence, it is necessary to provide in consideration of insulation between the electrode portion 13 and the electrodes and wiring members around the end portion 2a of the semiconductor chip 2.

  As described above, according to the third embodiment, the volume resistivity is higher than that of the insulating resin 8 inside the semiconductor device 1 and at least below the electrode portion 13 disposed above the end portion 2 a of the semiconductor chip 2. Therefore, even if an electric field is applied to the semiconductor chip 2 from the outside, the influence of the electric field on the electrodes and wiring members around the end 2a of the semiconductor chip or around the electrode part 13 is not emphasized. The electric field applied to the semiconductor chip 2 can be strengthened, and a highly sensitive deterioration diagnosis can be performed.

Embodiment 4 FIG.
The configuration of the semiconductor device according to the fourth embodiment will be described below. In the above-described first to third embodiments, since the electrode portion 13 is disposed inside the semiconductor device 1 and above the end portion 2a of the semiconductor chip, the electrode portion 13 is also present during normal operation of the semiconductor device 1. Will do. During operation of the semiconductor device 1, a slight electric field is also generated around the electrode portion 13 due to the voltage applied to the substrate upper electrode 4 or the upper surface electrode 9 of the semiconductor chip. For this reason, depending on the magnitude of the electric field generated around the electrode portion 13, the electrode portion 13 is also charged for a long period of time, and the semiconductor device 1 may be deteriorated due to this influence. In the present embodiment, the structure of the semiconductor device 1 is configured such that the electrode portion 13 is detachable, the electrode portion 13 is installed in the semiconductor device 1 at the time of deterioration diagnosis, and can be detached from the semiconductor device 1 except at the time of deterioration diagnosis. I will provide a.

  10A and 10B are diagrams illustrating the configuration of the semiconductor device according to the fourth embodiment. 10A shows a state in which the semiconductor device 1 is in operation and the electrode unit 13 is removed to the outside, and FIG. 10B shows a state in which the electrode unit 13 is attached to the inside of the semiconductor device 1 at the time of deterioration diagnosis. . 10A and 10B, the insulating resin 8 is provided with an insertion hole 20 that is opened from above and in which the electrode portion 13 can be installed.

In the state of FIG. 10A when the semiconductor device 1 is in operation, the insertion hole 20 is closed with a lid 21 that can be directly removed as indicated by an arrow. Further, the lid 22 of the case 7 facing the insertion hole 20 is also detachable as indicated by an arrow.
At the time of deterioration diagnosis, the detachable lid 22 is removed from the case, the lid 21 is removed from the insulating resin 8, and the electrode portion 13 is inserted into the insertion hole 20 as indicated by a dotted arrow. At the time of deterioration diagnosis, the state shown in FIG. 10B is obtained.

  The shape of the insertion hole 20 is desirably substantially the same as that of the electrode portion 13 having a clearance that allows the insertion of the electrode portion 13. Further, by providing the insertion hole 20, moisture may enter the insulating resin 8 through the insertion hole 20, which may promote moisture absorption deterioration of the semiconductor chip. For this reason, it is desirable to seal the insertion hole 20 using a lid 21 with high adhesion except during diagnosis. In addition, if the resin of the same material as the insulating resin 8 is made detachable in the same shape as the insertion hole 20 instead of the lid 21 shown in the drawing, that is, the shape of the electrode portion 13, it is possible to further maintain the sealing performance. Become.

  Moreover, it is desirable that the detachable lid 22 of the case 7 is configured so as to ensure sealing performance for the same reason.

  As described above, according to the fourth embodiment, in addition to the same effects as those of the first to third embodiments, the electrode unit 13 is configured to be detachable from the semiconductor device 1. It becomes possible to remove the part 13, and the deterioration promotion by the electrode part 13 being installed and being charged for a long term can be suppressed.

Embodiment 5 FIG.
Hereinafter, the configuration of the semiconductor device according to the fifth embodiment will be described. In the above-described first to fourth embodiments, the electrode portion 13 disposed above the end portion 2a of the semiconductor chip is disposed so as to face a part of the end portion 2a of the semiconductor chip. However, the occurrence of deterioration of the semiconductor chip is not uniformly deteriorated as a whole, but may be partially deteriorated in the end portion of the semiconductor chip. When the electrode part 13 is not disposed immediately above the deterioration occurrence part, there is a possibility that the sensitivity of deterioration diagnosis is lowered. In the fifth embodiment, the electrode portion 13 is arranged so as to face widely across the region of the end portion 2a of the semiconductor chip.

  11A and 11B are diagrams illustrating the configuration of the semiconductor device according to the fifth embodiment. 11A is a side view, and FIG. 11B is a perspective view showing the positional relationship between the periphery of the semiconductor chip 2 and the electrode portion 13. The electrode portion 13 is disposed so as to face the end portion 2 a of the semiconductor chip around the semiconductor chip 2. The central portion of the electrode portion 13 is a region facing the upper surface electrode 9 of the semiconductor chip 2 and is opened. Then, wiring is performed through the opening. Thus, the electrode part 13 is arrange | positioned so that the upper part of the edge part 2a of a semiconductor chip may be covered.

  When the electrode part 13 cannot be arranged so as to cover the upper part of the end part 2a of the semiconductor chip as shown in FIG. 11B, it may be arranged so as to cover the upper part of one side of the end part 2a of the semiconductor chip. 12A and 12B are other partial configuration diagrams showing the semiconductor device according to the fifth embodiment. 12A is a perspective view showing the positional relationship between the periphery of the semiconductor chip 2 and the electrode portion 13, and FIG. 12B is a top view showing the positional relationship between the periphery of the semiconductor chip 2 and the electrode portion 13. Thus, the electrode part 13 should just be arrange | positioned so that the upper part of one side of the edge part 2a of a semiconductor chip may be covered. 12A and 12B, the electrode portion 13 is arranged so as to cover the upper portion of one side of the end portion 2a of the semiconductor chip. However, the electrode portion 13 is arranged in an L shape when viewed from the upper surface, and two adjacent sides are arranged. Or may be arranged in a rectangular U shape so as to cover three adjacent sides. Further, an electrode corresponding to one side shown in FIGS. 12A and 12B may be provided on each side so as to cover the periphery of the end portion 2a of the semiconductor chip, or the L-shaped electrode portion 13 may be provided. Two may be combined.

  As described above, according to the fifth embodiment, the electrode portion 13 is shaped so as to be opposed to at least one region of the end portion 2a of the semiconductor chip and above the end portion 2a of the semiconductor chip. Thus, the same effects as those of the first to third embodiments are obtained, and the accuracy of deterioration diagnosis is further improved.

Embodiment 6 FIG.
The configuration of the semiconductor device according to the sixth embodiment will be described below. In Embodiment 5 described above, one electrode portion 13 is arranged above the end portion 2a of the semiconductor chip in the shape of the electrode portion 13 that is opposed over at least one side region. Then, the plurality of electrode portions 13 are arranged so as to face one side of the end portion 2a of the semiconductor chip.

  13A and 13B are partial configuration diagrams illustrating the semiconductor device according to the sixth embodiment. FIG. 13A is a perspective view showing the positional relationship between the periphery of the semiconductor chip 2 and the electrode portion 13, and FIG. 13B is a top view showing the positional relationship between the periphery of the semiconductor chip 2 and the electrode portion 13. A plurality of electrode portions 13 are arranged so as to cover an upper portion of one side of the end portion 2a of the semiconductor chip. Each of the plurality of electrode portions 13 is connected to the DC power supply 14 by a wiring 131.

If a voltage is applied to all of the plurality of electrode portions 13 arranged in this way, an electric field is generated over one side of the end portion 2a of the semiconductor chip, as in the example of FIGS. 12A and 12B of the fifth embodiment. Deterioration diagnosis can be performed. In this case, the electrodes 13 may be connected to apply a voltage.
In addition, by sequentially applying voltages to the plurality of electrode portions 13 and performing diagnosis in the vicinity of the end 2a of the semiconductor chip facing each of the electrode portions 13, it is possible to specify a degradation occurrence location.

  In FIG. 13A and FIG. 13B described above, the plurality of electrode portions 13 are arranged so as to cover the upper portion of one side of the end portion 2a of the semiconductor chip, but are L-shaped so as to cover the upper portions of two adjacent sides. A plurality of them may be arranged. Further, a plurality of rectangular U-shapes may be arranged so as to cover the upper part of three adjacent sides of the end 2a of the semiconductor chip, or a plurality of frames are arranged around the periphery of the end 2a of the semiconductor chip. May be.

  In order to make the structure of the above-described fifth and sixth embodiments detachable as in the fourth embodiment, an insertion hole corresponding to the shape of the electrode portion 13 may be provided in the insulating resin 8.

  As described above, according to the sixth embodiment, since the plurality of electrode portions 13 are arranged so as to face each other over at least one side region of the end portion 2a of the semiconductor chip, the same effect as that of the fifth embodiment is obtained. Play. In addition, it is possible to identify the location of deterioration by applying a voltage sequentially to the plurality of electrode portions 13 to diagnose the vicinity of the end 2a of the semiconductor chip facing each electrode portion 13, and The accuracy of deterioration diagnosis is improved.

Embodiment 7 FIG.
The configuration of the semiconductor device degradation diagnosis apparatus according to the seventh embodiment will be described below.
One of the causes of deterioration of a semiconductor device is the intrusion of moisture from the outside of the semiconductor device. When moisture gradually enters from the air outside the insulating resin, which is a sealing resin, and eventually reaches the semiconductor chip, deterioration of the semiconductor chip is promoted. Therefore, detecting the water absorption state of the insulating resin in the vicinity of the semiconductor chip is useful data in the deterioration diagnosis of the semiconductor chip itself. When the insulating resin absorbs water, the volume resistivity decreases. Therefore, by measuring the current flowing through the insulating resin, it is possible to detect the deterioration variation of the resin.

  FIG. 14 is a diagram showing a configuration of a semiconductor device deterioration diagnosis apparatus according to the seventh embodiment. In the figure, the configuration in which the electrode portion 13 is disposed in the insulating resin 8 above the end portion 2a of the semiconductor chip of the semiconductor device 1 is the same as in the first to sixth embodiments. An ammeter 11 is connected to the upper surface electrode 9 of the semiconductor chip 2.

  In the configuration of FIG. 14, when a high voltage is first applied to the electrode portion 13, a minute current flows in a direction from the electrode portion 13 toward the upper surface electrode 9 of the semiconductor chip 2 as indicated by an arrow in FIG. 14. The ammeter 11 measures the current that has flowed to the upper surface electrode 9 through the insulating resin 8. By measuring this current value, it is possible to grasp the water absorption state of the insulating resin 8 in the vicinity of the semiconductor chip 2. That is, when the insulating resin 8 gradually enters moisture from the beginning of the semiconductor device 1, the deterioration of insulation progresses, flows through the insulating resin 8, and the current measured by the ammeter 11 increases. An initial current is acquired in advance, used as a reference current, and a deterioration diagnosis can be performed by comparing with a measured current. Note that the voltage applied to the electrode portion 13 is equal to or lower than the dielectric breakdown voltage of the insulating resin 8 as in the first embodiment.

FIG. 15 is a diagram illustrating another configuration of the deterioration diagnosis apparatus for a semiconductor device according to the seventh embodiment, in which the ammeter 11 is connected to the substrate upper electrode 4. FIG. 16 is a diagram showing still another configuration of the deterioration diagnosis device for a semiconductor device according to the seventh embodiment, in which an ammeter 11 is connected to both the upper surface electrode 9 and the substrate upper electrode 4 of the semiconductor chip 2. It is.
In the configuration of FIG. 15, as indicated by an arrow in FIG. 15, a minute current flowing in the direction from the electrode portion 13 toward the substrate upper electrode 4 is measured by an ammeter 11 connected to the substrate upper electrode 4. At this time, when moisture enters from the outside toward the chip direction from the outside, the configuration of FIG. 15 measures the current flowing in the chip outside region more than the configuration of FIG. Can be detected. In the configuration of FIG. 16, as indicated by an arrow in FIG. 16, the ammeter 11 measures a minute current flowing from the electrode portion 13 toward the upper surface electrode 9 of the semiconductor chip 2 and toward the substrate upper electrode 4. To do. Since the current path is wide, the configuration of FIG. 16 is easier to detect the variation than the configurations of FIGS. However, FIG. 15 and FIG. 16 differ from FIG. 14 in that the connection of the ammeter needs to be changed from the time of the semiconductor chip deterioration diagnosis shown in the sixth embodiment.

  In addition, although the example which measures the electric current which goes to the electrode of the periphery of the semiconductor chip 2 from the electrode part 13 was shown in order to measure the electric current of the insulating resin 8, it does not restrict to this. For example, in the example in which the plurality of electrode portions 13 shown in the sixth embodiment are arranged, the current flowing between the electrode portions 13 may be measured. FIG. 17 is a diagram showing still another configuration of the semiconductor device deterioration diagnosis apparatus according to the seventh embodiment, in which the ammeter 11 is connected to one of the electrode sections 13. As shown in FIG. 17, a voltage may be applied to one electrode unit 13 and a current directed to another electrode unit 13 to which the ammeter 11 is connected may be measured.

  As described above, according to the seventh embodiment, the electrode portion 13 disposed in the insulating resin 8 in the semiconductor device 1 is used to mount the upper surface electrode 9 of the semiconductor chip 2 or the semiconductor chip from the electrode portion 13. The deterioration of the insulating resin 8 can be diagnosed by measuring the current flowing toward the periphery of the semiconductor chip 2 such as the substrate upper electrode 4 or by measuring the current flowing between the plurality of arranged electrode portions 13. Become. In addition, it is possible to perform comprehensive deterioration diagnosis as the semiconductor device 1 in combination with the first to sixth embodiments, and the accuracy of deterioration diagnosis is improved. In the flowchart of FIG. 3 of the first embodiment, after step S1, deterioration diagnosis of the insulating resin 8 may be performed before applying a voltage to the semiconductor chip 2.

  In the seventh embodiment, the deterioration of the insulating resin 8 is diagnosed by measuring the current flowing through the insulating resin 8 using the electrode portion 13 disposed in the insulating resin 8 in the semiconductor device 1. However, the deterioration diagnosis in the insulating resin 8 is not limited to this method. There is also a method of measuring a change in capacitance between predetermined insulating resins. Therefore, in the configuration of FIG. 17, the ammeter 11 is not connected to the electrode portion 13, but a capacitance meter is connected to the external path between the electrode portions 13, and the electrostatic resin 8 between the electrode portions 13 is electrostatically connected. Measure capacity. As in the case of the current change in the insulating resin 8 described above, when the insulating resin 8 gradually enters moisture from the initial stage of the semiconductor device 1, the deterioration of the insulation proceeds and the capacitance of the insulating resin 8 changes. The deterioration state of the insulating resin 8 may be diagnosed by setting the initial state as a reference capacitance and evaluating the fluctuation of the capacitance.

Although this disclosure describes various exemplary embodiments and examples, various features, aspects, and functions described in one or more embodiments may be described in terms of particular embodiments. The present invention is not limited to the application, and can be applied to the embodiments alone or in various combinations.
Accordingly, countless variations that are not illustrated are envisaged within the scope of the technology disclosed herein. For example, the case where at least one component is deformed, the case where the component is added or omitted, the case where the at least one component is extracted and combined with the component of another embodiment are included.

  DESCRIPTION OF SYMBOLS 1: Semiconductor device, 2: Semiconductor chip, 2a: End part of semiconductor chip, 3: Insulating substrate, 4: Substrate upper electrode, 5: Substrate lower electrode, 6: Heat sink, 7: Case, 8: Insulating resin, 9 : Top electrode, 10: Power supply, 11: Ammeter, 13: Electrode section, 14: DC power supply, 15, 16: Insulating film, 20: Insertion hole, 21: Cover, 22: Cover

Claims (11)

A semiconductor device having a semiconductor chip mounted via an insulating substrate and an electrode on the insulating substrate, wherein the insulating substrate and the semiconductor chip are sealed with an insulating resin,
A semiconductor device comprising: an electrode portion which is disposed in the insulating resin above and facing the end portion of the semiconductor chip so as to be electrically insulated from the semiconductor chip and to which a voltage can be applied from the outside.   At least a side surface of the electrode portion is covered with an insulating film having a volume resistivity higher than the volume resistivity of the insulating resin, and at least a part of the surface of the electrode portion facing the semiconductor chip is the insulating material. The semiconductor device according to claim 1, which is not covered with a film.   2. The semiconductor device according to claim 1, wherein at least a part of a surface of the electrode portion facing the semiconductor chip is covered with an insulating film having a volume resistivity lower than a volume resistivity of the insulating resin.   4. The semiconductor device according to claim 1, wherein the insulating resin has an insertion hole opened from above, and the electrode portion is detachably provided in the insertion hole. 5.   5. The semiconductor device according to claim 1, wherein the electrode portion is disposed so as to face along at least one side of an end portion of the semiconductor chip. 6.   5. The semiconductor device according to claim 1, wherein a plurality of the electrode portions are arranged to face an end portion of the semiconductor chip. A deterioration diagnosis device for a semiconductor device that performs deterioration diagnosis on a semiconductor device according to any one of claims 1 to 6 ,
A power supply for applying a voltage to the electrode section;
A power source for applying a voltage to the semiconductor chip;
An apparatus for diagnosing deterioration of a semiconductor device, comprising: an ammeter that measures a current flowing through the semiconductor chip. A degradation diagnosis device for a semiconductor device that performs degradation diagnosis on a semiconductor device according to any one of claims 1 to 5 ,
A power supply for applying a voltage to the electrode section;
An apparatus for diagnosing deterioration of a semiconductor device, comprising: an ammeter that measures a current flowing through the semiconductor chip. A semiconductor device according to claim 6;
A power supply for applying a voltage to the electrode section;
An apparatus for diagnosing deterioration of a semiconductor device, comprising: an ammeter for measuring a current flowing through the semiconductor chip; or an ammeter connected to one of the plurality of electrode portions. A degradation diagnosis method for a semiconductor device for diagnosing degradation of the semiconductor device according to any one of claims 1 to 6,
A first step of applying a voltage to the electrode part;
A second step of applying a reverse voltage to the semiconductor chip with a voltage applied to the electrode portion;
A third step of measuring the current flowing through the semiconductor chip;
A degradation diagnosis method for a semiconductor device, comprising: a fourth step of comparing a measured current with a reference current acquired in advance and performing a degradation diagnosis. After the first step, in a state where no voltage is applied to the semiconductor chip, measuring a current flowing through the insulating resin;
The deterioration diagnosis of a semiconductor device according to claim 10, further comprising a step of comparing the measured current flowing through the insulating resin with a reference current flowing through the insulating resin acquired in advance to perform a deterioration diagnosis of the insulating resin. Method.

Images