JP7450294B1 - Insulation performance test equipment for semiconductor devices - Google Patents

Abstract

The insulation performance testing apparatus A for semiconductor devices includes a constant temperature bath 3, a test board 10 on which the device under test 1 housed in the constant temperature bath 3 is mounted, a high voltage generator 60 that applies a high voltage to the device under test 1, and a circuit. From the switching mechanism section 21 that connects and disconnects the section 20, the multi-channel voltage waveform monitor 70 that monitors the current detection resistor 56 connected to the device under test 1 to identify the device under test 1a where dielectric breakdown has occurred, and the multi-channel voltage waveform monitor 70. and a circuit section cutoff mechanism section 80 that electrically disconnects the circuit section 20 in response to an activation command. The opening/closing mechanism section 21 includes a fixed terminal section 30 and a movable terminal section 40 that moves toward and away from the fixed terminal section 30 to connect and disconnect it. The circuit section cutoff mechanism section 80 moves the movable side terminal section 40 to cut off (turn off) the fixed side terminal section 30.

Description

The present invention relates to improvements in insulation performance testing equipment for semiconductor devices.

In order to ensure electrical safety, it is necessary to test the insulation performance of semiconductor devices before they are distributed on the market to ensure product reliability. Insulation performance testing is especially important for switching elements that cut off voltage (transistors, thyristors, etc.) and signal isolation semiconductor devices that transmit only signals while maintaining insulation (photocouplers, digital isolators, isolation amplifiers, etc.) This is an item. In addition, in the description of this application, "semiconductor element" or "element" refers to electronic components using semiconductors, including so-called discrete semiconductor elements as well as semiconductor devices, which are integrated circuit elements that incorporate semiconductors inside. shall be.

Examples of the insulation performance test include a withstand voltage test, a Vt test, a voltage step-up test, and a TDDB (Time Dependent Dielectric Breakdown) test. Both tests apply voltage to the electrodes of the device under test and measure the voltage at which the device breaks down and the time it takes to break down the device. In particular, the TDDB test is a test for evaluating the insulation life of a semiconductor element, and is becoming an essential test for semiconductor elements that require high reliability. If a voltage is continuously applied to the oxide film of a semiconductor device, the oxide film required for electrical insulation will break down over time. By accelerating this test by performing tests under high-voltage and high-temperature conditions, where breakdown occurs more quickly, it becomes possible to estimate the insulation life of a product from several decades to a few days to a few months. .

The insulation performance tests shown above are mainly conducted in the atmosphere, but there are cases where it is necessary to conduct tests using very high voltages, such as insulation evaluation of high-voltage semiconductor elements, and when high voltages are used. When conducting accelerated tests, insulation performance tests must be conducted in insulating oil to prevent arc discharge. Patent Document 1 discloses an apparatus that performs an insulation performance test both in air and in oil.
Furthermore, these insulation performance tests must be performed on a large number of devices under test, and the insulation performance must be evaluated through statistical analysis. In order to shorten the evaluation time, it is necessary to simultaneously measure multiple devices under test. Patent Document 2 discloses a method in which a circuit using a current limiting resistor or a current fuse is formed, voltages are applied in parallel to a plurality of devices under test, and tests can be performed simultaneously.

Mito 3092703 JP 09-213760

In parallel insulation performance tests on a large number of semiconductor devices in oil, there are cases where the elapsed time and applied voltage are measured when even one of the many devices fails, and there are cases where the set number or all of the devices under test are measured. Various tests are conducted, including cases in which the elapsed time until destruction and the applied voltage are measured. In the latter case, the destroyed device under test is removed and the test continues with the remaining devices under test. The task of removing the destroyed device under test is to interrupt the test, have the worker manually remove it from the oil, and then restart the test. This was accompanied by contamination and time loss due to element removal work.

In order to improve work efficiency, it is necessary to abolish manual work by workers. It is conceivable to install an opening/closing mechanism such as a relay for each device under test outside the insulating oil tank to automatically turn on and off the circuit of the device under test that has dielectric breakdown, but relays used at high voltages are generally small in size. is large and expensive, leading to an increase in the size and price of the device. In addition, the high-voltage conductor has a thick insulation coating, and a bundle of multiple high-voltage conductors must be led to the relay. In addition, thick conductive wires wired in a bundle are wired in insulating oil, which not only makes the container too large, but also obstructs insulation due to the thick conductive wires wired in insulating oil. There are problems such as inhibiting oil convection and making it impossible to maintain a uniform temperature of the insulating oil. Further, as disclosed in Patent Document 2, the method of using a current fuse to cut off the voltage supply to an element whose insulation has been broken down is effective in low voltage tests, but In this case, the size becomes very large, and it cannot be applied for the same reason as the case of relays.

The present invention has been made in view of the problems of the conventional example. First, by configuring the opening/closing mechanism for turning on and off the high voltage to the device under test in insulating oil, the high voltage that occupies a large volume The conductor is omitted, the container size is made compact, and the convection of the insulating oil is not obstructed.Secondly, a part of the opening/closing mechanism is made to protrude above the oil level, and that part is held and moved. It is possible to turn on and off high voltage without coming into contact with insulating oil, and thirdly, it is possible to automatically shut off the circuit section in which the device under test that has dielectric breakdown is mounted, minimizing test interruption time. The purpose of the present invention is to provide an insulation performance testing device for semiconductor devices that enables shortening of test time and reduction of working labor.

Claim 1 relates to an insulation performance testing apparatus A for a semiconductor device, which is a device under test 1 (FIGS. 1 and 4),
A constant temperature bath 3 filled with insulating oil 100,
The circuit section 20 is disposed in the thermostatic chamber 3 and includes a semiconductor device as the device under test 1 and a current detection resistor 56 connected to the device under test 1. A test board 10 immersed in insulating oil 100 to a submerged position;
a high voltage generator 60 that applies a high voltage to the device under test 1 via the circuit section 20;
an opening/closing mechanism section 21 that is provided in the circuit section 20 and connects/disconnects (on/off) the circuit section 20;
The voltage waveform of each current detection resistor 56 of a plurality of circuit sections 20 provided on one or more test boards 10 is monitored, the voltage waveform is stored, and dielectric breakdown is caused based on the position information of the stored voltage waveform. In the insulation performance testing apparatus A for semiconductor devices, which is configured with a multi-channel voltage waveform monitor 70 that specifies the device under test 1a,
The opening/closing mechanism part 21 includes a fixed terminal part 30 provided in the circuit part 20 and provided with first and second fixed terminal members 30a and 30b immersed in insulating oil 100, and It is characterized by comprising a movable side terminal part 40 that moves toward and away from the terminal members 30a and 30b to connect and disconnect the first and second fixed side terminal members 30a and 30b.

Claim 2 provides the insulation performance testing apparatus A for semiconductor elements according to claim 1 (FIG. 2),
A catch portion 41d that is provided on the head of the movable terminal portion 40 and serves as a grip portion for separating the movable terminal portion 40 from the first and second fixed terminal members 30a and 30b. It is characterized in that it is provided so as to protrude above the oil level of the insulating oil 100.

Claim 3 provides the insulation performance testing apparatus A for semiconductor elements according to claim 1 or 2 (FIG. 4),
It further includes a circuit section cutoff mechanism section 80 that operates the opening/closing mechanism section 21 to electrically disconnect the circuit section 20,
The circuit section interrupting mechanism section 80 moves the corresponding movable side terminal section 40 to the first and second fixed terminals according to the position information of the destroyed device under test 1a detected by the multi-channel voltage waveform monitor 70. It is characterized in that the side terminal members 30a and 30b are cut off (turned off).

Claim 4 provides an insulation performance testing apparatus A for semiconductor elements according to claim 1 or 2 (FIG. 4),
The first and second fixed side terminal members 30a and 30b of the fixed side terminal section 30 are composed of cylindrical members,
The movable terminal section 40 is characterized by being comprised of a pin-shaped member that can be inserted into and removed from the first and second fixed terminal members 30a and 30b.

Claim 5 provides an insulation performance testing apparatus A for semiconductor elements according to claim 3 (FIG. 1, FIG. 5(c)),
The circuit section cutoff mechanism section 80 is
a plane moving unit 81A that moves within a plane that covers the placement area of the test board 10;
a vertical movement section 81B that is provided on the plane movement section 81A and moves in the vertical direction;
It is attached to the vertically moving part 81B, holds the movable side terminal part 40 of the opening/closing mechanism part 21, and moves the movable side terminal part 40 while being held, and the first and second fixed side terminal members 30a and 30b and an end effector 86 that separates the movable side terminal section 40 from the movable side terminal section 40 and shuts off (turns off) between the first and second fixed side terminal members 30a and 30b.

Claim 6 provides the insulation performance testing apparatus A (three-dimensional table) for semiconductor elements according to claim 5 (FIG. 1),
The plane moving part 81A is
An X-direction rail 81x arranged along one side of the arrangement area of the test board 10;
an X-direction moving body 82x that moves along the X-direction rail 81x;
a Y-direction rail 81y mounted on the X-direction moving body 82x and arranged orthogonally to the X-direction rail 81x;
and a Y-direction moving body 82y that moves along the Y-direction rail 81y,
The vertical movement section 81B is
A Z-direction rail 81z vertically installed on the Y-direction moving body 82y,
The vertical (Z) direction moving body 82z moves along the Z direction rail 81z.

A seventh aspect of the present invention provides the semiconductor element insulation performance testing apparatus A (three-dimensional robot arm 83: FIG. 5(c)) according to the fifth aspect,
The planar moving section 81A and the vertical moving section 81B are characterized by being composed of a robot arm 83 capable of three-dimensional movement.

Claim 8 provides an insulation performance testing apparatus A for semiconductor elements according to claim 5 (electromagnet: FIG. 5(a)),
The end effector 86 of the circuit interrupting mechanism section 80 is composed of an electromagnet 86a,
A catch portion 41d of the movable terminal portion 40 held by the end effector 86 is made of a magnetic material.

Claim 9 provides an insulation performance testing apparatus A for semiconductor elements according to claim 5 (attraction force: FIG. 5(b)),
The end effector 86 of the circuit section interrupting mechanism section 80 is characterized in that it includes a suction cup 86b that attracts the catch section 41d of the movable side terminal section 40.

Claim 10 provides the insulation performance testing apparatus A for semiconductor elements according to claim 5 (scissors member: FIG. 5(c)),
The end effector 86 of the circuit section interrupting mechanism section 80 is characterized in that it includes a scissor member 86c that pinches the catch section 41d of the movable terminal section 40.

Claim 11 provides an insulation performance testing apparatus A for semiconductor devices according to claim 1 or 2 (FIGS. 3 and 4),
The test board 10 includes a main body portion 11a on which the circuit section 20 is installed, and an extending portion 11b extending upward from the upper end thereof,
The movable terminal portion 40 of the opening/closing mechanism portion 21 is provided with a guide groove 45 into which the extension portion 11b is inserted and a holding groove 46 extending upward from the lower end of the movable terminal portion 40.
The guide groove 45 is longer than the holding groove 46 and is configured such that the extending portion 11b is inserted when the movable terminal portion 40 contacts the fixed terminal portion 30,
The holding groove 46 is characterized in that the extending portion 11b is inserted into the holding groove 46 so that the movable terminal portion 40 is kept separated from the fixed terminal portion 30.

The opening/closing mechanism section 21 of the present invention includes a fixed terminal section 30 having first and second fixed terminal members 30a and 30b, and a fixed terminal section 30 that is connected to and separated from the first and second fixed terminal members 30a and 30b. , and a movable side terminal part 40 that connects and disconnects the first and second fixed side terminal members 30a and 30b, and since these are immersed in insulating oil 100, high voltage conductors that occupy a large volume are omitted. In addition, the container size can be made compact, the convection of the insulating oil is not obstructed, and only the circuit section 20 of the device under test 1 having dielectric breakdown can be shut off with a simple structure.
Since the catch portion of the opening/closing mechanism section 21 that opens and closes the movable terminal section 40 protrudes above the oil level of the insulating oil 100, the movable terminal section 40 can be moved without coming into contact with the insulating oil 100. The device under test 1 can be disconnected from the circuit by simply opening and closing the movable terminal section 40, and the surroundings of the device will not be contaminated by insulating oil due to the opening and closing operations of the moving side terminal section 40. Furthermore, the process required to disconnect high voltage to the device can be avoided. can also be significantly reduced.

Further, in the configuration including the circuit section breaking mechanism section 80, upon receiving the position information of the destructive element from the multi-channel voltage waveform monitor 70, the circuit section breaking mechanism section 80 automatically moves the corresponding movable side terminal section 40. Since the first and second fixed side terminal members 30a and 30b are cut off (turned off), the interruption time of the test can be minimized, and there is no need for the operator to stay in the equipment all the time, which saves test time and work effort. Significant reductions are possible.

Then, the opening/closing mechanism section 21 configures the first and second fixed terminal members 30a and 30b of the fixed terminal section 30 immersed in the insulating oil 100 with cylindrical members, and the movable terminal section 40 with the cylindrical member. It is composed of a pin-shaped member that can be inserted into and removed from the fixed side terminal section 30, and the high voltage circuit for connecting and disconnecting high voltage is completed within the insulating oil 100, so there is a thick tube for applying high voltage. There is no need to run conductive wires inside and outside the thermostatic chamber 3, and in addition, the opening/closing mechanism section 21 can be downsized by arranging the high voltage section in oil, and the device size can be made compact.

1 is a schematic perspective view of an embodiment of the device of the invention; FIG. FIG. 2 is a partially enlarged perspective view showing a part of the internal wiring structure shown in FIG. 1. FIG. (a) to (d) are perspective views showing the behavior of the moving side terminal in FIG. 1; FIG. 2 is an enlarged perspective view showing the main parts of the circuit configuration of the present invention. (a) to (c) are perspective views showing examples of end effectors of the present invention. 1 is a schematic block circuit diagram of the present invention; FIG.

The present invention will be described below based on illustrated embodiments. Note that this embodiment is provided to facilitate understanding of the present invention by those skilled in the art. That is, it should be understood that the present invention is limited only by the technical idea described throughout the specification, and is not limited only to this embodiment.

The insulation performance testing apparatus A for semiconductor devices according to the present invention shown in FIGS. It consists of a voltage waveform monitor 70. Furthermore, by providing the circuit section cutoff mechanism section 80, it becomes possible to cut off high voltage to the elements through automatic control.
The test board 10 is provided with a circuit section 20 on which the device under test 1 is mounted. In the present invention, a plurality of devices under test 1 are continuously tested at the same time, and as described above, the voltage, time and temperature conditions, set number of devices, and Since the voltage, time and temperature conditions until all the elements 1 undergo dielectric breakdown are tested, the circuit sections 20 are divided into one or more test boards 10 as many as the elements 1 to be tested. If the number of circuit parts 20 is too large to be accommodated on one test board 10, the test board 10 is divided into a plurality of parts.

Since the voltage applied to the device under test 1 is a high voltage of several kV to several tens of kV, the air-conducting portion outside the insulating oil 100 constituting the circuit section 20 requires thick insulation coating, and thick conductive wires are used. Therefore, by completing the high voltage part of the opening/closing mechanism part 21 that connects and disconnects (on/off) the circuit part 20 configured on the test board 10 in the insulating oil 100, aerial wiring can be eliminated and the device size can be reduced. In order to suppress this, the structure must be simple. In the following description, a case where the test board 10 including a plurality of circuit sections 20 is divided into a plurality of sheets will be explained as a typical example (FIGS. 1 and 6).

The device under test 1 to which the present invention is applied uses, for example, a discrete semiconductor such as a high-voltage switching transistor, thyristor, or MOSFET, or a photodiode, transformer, or capacitor to optically transmit data through an insulating layer. Examples include photocouplers, digital isolators, which are magnetically or capacitively coupled isolation type signal insulating semiconductors. Insulation of semiconductor elements is mainly achieved by oxide films, but high insulation is sometimes ensured by polyimide or silicon dioxide.

The constant temperature bath 3 used in the device A of the present invention has an insulating structure container for storing insulating oil 100, a thermometer (not shown), a switch (not shown) linked to the thermostat (not shown), a heat source (not shown), and a thermostat (not shown). (not shown) and a cooler (not shown) are installed. The constant temperature bath 3 can be controlled to maintain the liquid temperature inside the container at a set temperature by automatically turning these on and off.
Silicone oil or the like is used as the insulating oil 100.
In order to maintain a uniform temperature of the insulating oil 100 inside the container having an insulating structure, a circulation device (not shown) for circulating the insulating oil 100 may be installed. The set temperature of the insulating oil 100 can be changed.

In order to arrange the test substrates 10 at regular intervals inside the container, holding grooves 5 are carved at regular intervals on the upper surface of the side wall of the container of the insulating structure of the constant temperature chamber 3, and holding grooves 5 are carved on the bottom surface of the constant temperature chamber 3. A protrusion 6 is provided. The number of holding grooves 5 arranged in one row is equal to the number of test substrates 10.
Further, a first conductor bar 7 for applying a high voltage is installed horizontally on the inner surface of one side wall of the thermostatic oven 3, and a second conductor bar 8 is installed horizontally on the inner surface of the other side wall. The first conductor bar 7 is connected to a high voltage generator 60, and the second conductor bar 8 is grounded. Ground is indicated by 90.
The first conductor bar 7 and the second conductor bar 8 are provided with conductive holes 7h and 8h corresponding to the holding grooves 5, respectively, for establishing conduction with the circuit section 20 provided on the test board 10. (Figure 2).

The test board 10 includes a board main body 11, a handle 13, a circuit section 20 provided on the board main body 11, and an opening/closing circuit that constitutes a part of the circuit section 20 and switches a high voltage application circuit to the device under test 1. It is composed of a mechanism section 21 and first and second conductive pins 14a and 14b (FIG. 2).
The board main body 11 includes a substantially rectangular plate-shaped main body portion 11a and a rectangular extending portion 11b extending upward from the upper end of the main body portion 11a corresponding to the arrangement position of the circuit section 20. The substrate body 11 is made of a resin that is resistant to heat, such as high Tg glass epoxy.
On both side edges of the main body portion 11a, there are provided handles 13 having an inverted L shape and arranged symmetrically, and the locking portions 13k of the handles 13 are provided facing outward with respect to the main body portion 11a.

In the present invention, since a large number of devices under test 1 are subjected to dielectric breakdown testing at the same time, a plurality of (for example, six) circuit sections 20 are provided for one test board 10, and A plurality of (for example, eight) substrates 10 are used.
Regarding the test board 10, although not shown, if the number of devices under test 1 is small, a plurality of circuit parts 20 may be arranged in parallel on one test board 10, or one circuit part 20 may be arranged in parallel on one test board 10. may be provided on one test board 10, and a plurality of these may be used.
In this embodiment, since a large number of devices under test 1 must be continuously measured, a plurality of circuit sections 20 are provided for one test board 10, and a plurality of circuit sections 20 are used.

The circuit part 20 of the test board 10 is a part surrounded by a broken line in FIG. 6, and is a circuit connected in parallel between a high voltage application side conductor 57a and a low voltage side conductor 57b provided on the board main body 11, and is a circuit that can be opened and closed. It is composed of a mechanism section 21, a current limiting resistor 54, a socket 55, a current detecting resistor 56, and a conductor connecting these. The plurality of circuit units 20 are connected in parallel between a high voltage application side conductor 57a and a low voltage side conductor 57b.
The high voltage application side conductor 57a is a substrate pattern extending from the first conductive pin 14a on the high voltage generator 60 side. The low voltage side conductor 57b is a board pattern extending from the second conductive pin 14b on the ground 90 side.
In this embodiment, since there are a plurality of test boards 10, the circuit sections 20 of each test board 10 are connected in parallel via the first and second conductor bars 7 and 8.
The conduction between the first and second conductor bars 7 and 8, the high voltage application side conductor 57a, and the low voltage side conductor 57b is established by the first and second conduction pins 14a and 14b provided on the side edge of the board body 11. This is done by being inserted into the conductive holes 7h and 8h of the first and second conductor bars 7 and 8.

When the device under test 1 is a packaged IC, using the socket 55 makes it easy to replace the device under test 1. The socket 55 of each circuit section 20 has a first terminal 55a and a second terminal 55b to which terminals of the device under test 1 are respectively connected. The conductor portion indicated by a broken line in FIG. 4 between the first terminal 55a on the high voltage application side and the high voltage application side conductor 57a is the high voltage application side relay portion 58a (first terminal 55a⇒connection conductor 31b⇒ Sheath tube 32b⇒Switching member 42b⇒Switching member 42a⇒Sheath tube 32a⇒Connection conduction portion 31a⇒High voltage application side conductor 57a), and is indicated by a broken line between the second terminal 55b on the ground side and the low voltage side conductor 57b. The connected conductor is the low voltage side relay portion 58b (second terminal 55b⇒low voltage side conductor 57b). If the device under test 1 has a shape that does not allow the use of the socket 55, or if the test is performed under high temperature conditions where a socket cannot be used, solder it directly onto the pattern formed on the test board 10, or solder it onto the board. The device under test 1 is loaded onto the circuit section 20 using the mounted dedicated connector.

The first and second conduction pins 14a and 14b are attached to the side edges of the substrate body 11 facing downward in alignment with the conduction holes 7h of the first conductor bar 7 and the conduction holes 8h of the second conductor bar 8, respectively.
The first conduction pin 14a on the high voltage side is connected to the end of the high voltage application side conductor 57a, and the second conduction pin 14b on the low voltage side is connected to the end of the low voltage side conductor 57b. The first and second conduction pins 14a and 14b are thick rod-shaped members made of copper, and are formed to be insertable and removable according to the inner diameters of the conduction holes 7h and 8h. The first and second conduction pins 14a and 14b are plate spring-shaped contact pieces (not shown) provided in the conduction holes 7h and 8h so that conduction can be established when inserted into the conduction holes 7h and 8h, respectively. It is designed to be contacted at

The socket 55 is a device for mounting the device under test 1 and testing insulation performance, and one socket 55 is installed in each circuit section 20. One first terminal 55a of the socket 55 is connected to a high voltage application side conductor 57a via a high voltage application side relay part 58a, and the other second terminal 55b is connected to a low voltage side conductor 57a via a low voltage side relay part 58b. 57b. First terminals 55a and 55b of the socket 55 are respectively connected to terminals (not shown) of the mounted device under test 1.

The current limiting resistor 54 is installed in the high voltage application side relay part 58a (in this embodiment, between the connecting conductive part 31b on the socket 55 side and the first terminal 55a of the socket 55), and is installed in the high voltage applying side relay part 58a (in this embodiment, between the connecting conductive part 31b on the socket 55 side and the first terminal 55a of the socket 55), and is connected to the device under test 1 in the event of dielectric breakdown. This serves to prevent the high voltage generator 60 from being damaged due to excessive current flowing through it.
The current detection resistor 56 is installed in the low-voltage side relay section 58b (in this embodiment, between the second terminal 55b of the socket 55 and the low-voltage side conductor 57b), and prevents current from flowing to the device under test 1 at the time of dielectric breakdown. generates voltage when

The opening/closing mechanism section 21 is provided for each circuit section 20, and when a dielectric breakdown occurs in the device under test 1, it shuts off only the circuit section 20 and allows measurement of the remaining devices under test 1 to be resumed. In this embodiment, it is provided in the middle of the high voltage application side relay section 58a. (Although not shown, it may of course be provided in the middle of the low voltage side relay section 58b.)
Since this test equipment A handles high voltage, very thick conductors with thick insulation coatings are used for the aerial wiring. Furthermore, high-pressure air opening/closing mechanisms (relays) are generally very large. Therefore, in order to make the device size more compact, it is necessary to complete the opening/closing mechanism section 21 in insulating oil and to have a simple structure.

FIG. 4 shows an example of the opening/closing mechanism section 21. The opening/closing mechanism section 21 is divided into a fixed terminal section 30 and a movable terminal section 40.
The fixed side terminal section 30 is composed of first and second fixed side terminal members 30a and 30b arranged side by side. Since these terminal members must have high mechanical strength and electrical conductivity, they are manufactured from gold-plated beryllium copper.
The first fixed side terminal member 30a includes a block-shaped connection conduction portion 31a fixed to the board body 11, and a cylindrical portion extending upward from the connection conduction portion 31a and a sheath pipe 32a. The first fixed terminal member 30a is connected to the high voltage application side conductor 57a.
The second fixed side terminal member 30b has a block-shaped connecting conductive portion 31b that penetrates through the main body portion 11a and is connected to the first terminal 55a on one application side of the socket 55, and a block-shaped connecting conductive portion 31b that extends upward from the connecting conductive portion 31b. The elongated cylindrical portion is composed of a sheath tube 32b.
A leaf spring (not shown) is provided inside the sheath tubes 32a, 32b to lightly elastically contact switching members 42a, 42b of a movable terminal section 40, which will be described later, to establish electrical continuity.
The first and second fixed side terminal members 30a and 30b are both immersed in insulating oil 100 to avoid air discharge.

The movable terminal section 40 includes a terminal body 41 made of resin, and two metal pin-shaped switching members 42a and 42b hanging downward from the lower surface of the terminal body 41.
The switching members 42a and 42b have a diameter that allows them to be inserted into and removed from the insertion/removal holes of the sheath tubes 32a and 32b, and are designed so that they make light elastic contact with a leaf spring (not shown) inside the sheath tubes 32a and 32b when inserted. It has become.
The switching members 42a and 42b are immersed in the insulating oil 100 at least while they are electrically connected to the first and second fixed terminal members 30a and 30b.

The terminal main body 41 can be inserted into and removed from the extending portion 11b of the board main body 11, and when the switching members 42a and 42b of the movable terminal section 40 are separated from the sheath tubes 32a and 32b of the fixed terminal section 30, the terminal main body 41 is in a detached state. The structure is such that it can hold. An example is shown below.
The terminal body 41 includes a central member 41a, side members 41b and 41c attached to both sides thereof, and a catch portion 41d attached to cover the upper surfaces of the terminal body 41 and the side members 41b and 41c. The central member 41a and the side members 41b and 41c have the role of insulating the switching members 42a and 42b, which are high voltage parts, and the catch part 41d, and therefore need to be made of a heat-resistant insulator. For example, it is made of resin such as PEEK (peak material) or alumina. The two switching members 42a and 42b are provided vertically downward from the lower surface of the central member 41a of the terminal body 41. The switching members 42a and 42b are electrically connected within the terminal body 41 as shown by broken lines.
The catch portion 41d protrudes above the oil level of the insulating oil 100, and by holding this portion, the entire movable side terminal portion 40 can be moved without coming into contact with the insulating oil 100.

Guide grooves 45 and holding grooves 46 are provided side by side on the inner surfaces of the side members 41b and 41c from the lower end toward the upper end. The guide groove 45 and the holding groove 46 are open at the lower ends of the side members 41b and 41c. The holding groove 46 extends from the lower end to the upper end of the side members 41b and 41c. The length of the holding groove 46 is shorter than that of the guide groove 45.
The inner dimensions of the guide groove 45 and the holding groove 46 are slightly larger than the thickness of the extending portion 11b, so that the sides of the extending portion 11b are inserted into the guide groove 45 and the holding groove 46, respectively.

It is sufficient that the catch portion 41d has a function of being able to come into contact with and separate from an end effector 86 of a circuit section interrupting mechanism section 80, which will be described later.
When the end effector 86 is composed of an electromagnet (FIG. 5(a)), a block of ferromagnetic material such as iron is used as the catch portion 41d. This case will be described below as a representative example. Other examples will be discussed later.

Multi-channel voltage waveform monitor 70 includes voltage waveform detection sensors (not shown) individually connected to current detection resistor 56 .
The multi-channel voltage waveform monitor 70 has the function of detecting the voltage waveform of the current detection resistor 56 that occurs when any of the elements under test 1 undergoes dielectric breakdown during the test, the function of storing the detected voltage waveform, and the function of recording the voltage. This device has a function of specifying a voltage waveform detection sensor and specifying the position of an element under test 1 having dielectric breakdown among a large number of elements 1 under test. In addition, there is also a function to operate the circuit section cut-off mechanism section 80 immediately after dielectric breakdown is detected, and to operate the opening/closing mechanism section 21 in order to cut off the circuit section 20 in which the dielectrically broken device under test 1 is mounted. It may also have the function of restarting the high voltage generator 60 and restarting the inspection after being shut off. The number of voltage waveform detection sensors equal to the number of devices under test 1 is prepared, and as described above, they are connected to the current detection resistor 56 to continuously monitor the insulation state of the device under test 1.

The high voltage generator 60 is a device that converts an input AC or DC voltage into an AC or DC high voltage using an internal power conversion circuit. As such devices, for example, devices such as transformers, DC-DC converters, and switching power supplies are used. The high voltage generator used in the present invention converts a general voltage into a high voltage (eg, 10 kV) required for inspection. In some cases, the high voltage generator 60 includes an internal current detection circuit and a cutoff circuit, and has a function of immediately cutting off the current when the insulation of the device under test is broken and a certain amount of current flows.

The circuit section cutoff mechanism section 80 is provided as necessary. In the case where the circuit part breaking mechanism part 80 is not provided, the circuit part breaking mechanism part 80 in FIG. The circuit section 20 is cut off by pulling it out from the section 30.
There are various types of circuit interrupting mechanisms 80 that are provided as needed, such as a three-dimensional XYZ table and a three-dimensional robot arm.
In this embodiment, a three-dimensional XYZ table is taken as an example of the circuit section cutoff mechanism section 80. The movable part of the circuit interrupting mechanism section 80, which is composed of a three-dimensional XYZ table, is composed of a plane moving section 81A and a vertical moving section 81B. (described later) is attached to an end effector 86.
A control section (not shown) of the circuit section breaking mechanism section 80 is connected to the multi-channel voltage waveform monitor 70, and according to the information from the multi-channel voltage waveform monitor 70, the control section (not shown) handles the opening/closing mechanism section 21 and detects the dielectric breakdown under test. It has a function of automatically shutting off the circuit section 20 of the element 1.

The plane moving unit 81A has a function of moving within a plane that covers the arrangement area of the plurality of test boards 10 suspended in the thermostatic chamber 3, and includes an X-direction rail 81x, an X-direction moving body 82x, and a Y-direction rail 81y. , and a Y-direction moving body 82y.
The X-direction rail 81x is arranged in the X-direction along one side of a plane that covers the placement area of the test board 10.
The X-direction moving body 82x reciprocates along the X-direction rail 81x.
The Y-direction rail 81y is attached to the X-direction moving body 82x, and is arranged in the Y-direction perpendicular to the X-direction rail 81x.
The Y-direction moving body 82y reciprocates along the Y-direction rail 81y.

The vertical moving section 81B is composed of a Z-direction rail 81z and a vertical (Z)-direction moving body 82z.
The Z direction rail 81z is vertically installed on the Y direction moving body 82y, and the vertical direction moving body 82z is configured to reciprocate in the vertical direction along the Z direction rail 81z.
The end effector 86 is a part for operating the movable terminal section 40 and is attached to the vertically moving body 82z.

There are various types of end effector 86, such as one that uses an electromagnet 86a, one that uses suction with a suction cup 86b, and one that pinches the catch portion 41d of the movable terminal section 40 with a scissor member 86c. An example will be explained using an electromagnet 86a.

An electromagnet 86a is built inside the end effector 86, and when the movable terminal section 40 is moved, the electromagnet 86a works to hold the catch portion 41d at the head of the movable terminal section 40, and the movable terminal section 40 When the movement is completed, the power supply is cut off and the holding is released.
Since the catch portion 41d at the head of the movable terminal portion 40 protrudes above the oil level of the insulating oil 100, the end effector 86 can perform the above moving operation without coming into contact with the insulating oil 100. In addition, since the movement range of the end effector 86 is limited to the range where the catch portion 41d is arranged, it is possible to avoid contamination of the insulating oil around the outside of the thermostatic chamber 3 by the insulating oil 100.

Next, the flow of testing the device under test 1 using this testing apparatus will be explained.
A plurality of test substrates 10 are suspended in the constant temperature bath 3 at regular intervals. The locking portion 13k of the handle 13 and the lower edge of the substrate body 11 of the test substrate 10 are fitted into the holding grooves 5 of the thermostatic chamber 3, and are fixed to the thermostatic chamber 3 at regular intervals.
The first and second conductive pins 14a and 14b of the test board 10 are inserted into the conductive holes 7h and 8h of the first and second conductor bars 7 and 8, and conduction is established in these portions.
Furthermore, the switching members 42a and 42b of each opening/closing mechanism section 21 are inserted into the sheath tubes 32a and 32b, and electrical continuity is also maintained in these portions.
Each socket 55 has a device under test 1 mounted thereon. (In this example, a configuration using the socket 55 will be explained.)
Insulating oil 100 is stored in constant temperature bath 3 until the element under test 1 and sheath tubes 32a and 32b are submerged in insulating oil 100. The insulating oil 100 is adjusted to a set temperature, and as a result, the temperature of all the tested elements 1 is at the set temperature.

In this state, the high voltage generator 60 generates a high voltage of, for example, 10 kV. The first conductor bar 7, the first conducting pin 14a of the test board 10, the high voltage application side conductor 57a, one connecting conducting part 31a of the opening/closing mechanism section 21, one sheath tube 32a, and the one inserted into this sheath tube 32a. switching member 42a, another switching member 42b that is short-circuited with one switching member 42a, another sheath pipe 32b into which this other switching member 42b is inserted, the other connecting conduction portion 31b, and the first terminal of the socket 55. A high voltage is applied to one terminal of the device under test 1 connected to the first terminal 55a through a path 55a.

One terminal of the device under test 1 is connected to the second terminal 55b of the socket 55, and is connected to the ground 90 through the second conductive pin 14b and the second conductor bar 8. As a result, a high voltage is applied to the device under test 1 mounted in the socket 55.
When the high voltage is direct current, the high voltage is continuously applied to the device under test 1 from the first terminal 55a side, and when it is alternating current, the direction of high voltage application is switched in accordance with the frequency.

In this state, the test is continued by maintaining the applied voltage and the temperature setting of the insulating oil 100, or by changing these as necessary.
If any of the elements under test 1 is damaged and the insulation is broken during the test, a current flows through the element under test 1 and a voltage is generated across the current detection resistor 56. At this time, the current flowing through the device under test 1 is limited by the current limiting resistor 54 to prevent excessive current from flowing through the device under test 1 and damaging the high voltage generator 60. The high voltage generator 60 immediately stops energizing after the current flowing due to dielectric breakdown is detected.
The multi-channel voltage waveform monitor 70 detects and stores this instantaneously generated voltage waveform.

Subsequently, the multi-channel voltage waveform monitor 70 identifies the sensor that detected the voltage waveform caused by the dielectric breakdown from among the stored voltage waveforms, and thereby identifies the position of the device under test 1a where the dielectric breakdown occurred. When the location of the dielectrically broken device under test 1a is specified, the location information is output to the circuit section interrupting mechanism section 80. Having received the information, the circuit interrupting mechanism section 80 activates its horizontal moving section 81A and moves its vertical moving section 81B to a position directly above the device under test 1 that has undergone dielectric breakdown. The vertical moving unit 81B, which stopped directly above the dielectrically broken device under test 1, lowered the vertical moving body 82z carrying the end effector 86, and the end effector 86 came into contact with the catch portion 41d of the moving terminal unit 40. stop it at that point. Subsequently, the electromagnet 86a of the end effector 86 is energized, and the catch portion 41d is magnetically attached by the electromagnet 86a.

When the end effector 86 magnetizes the catch portion 41d, the vertically moving body 82z is raised, and the switching members 42a and 42b of the movable terminal portion 40 are pulled out from the sheath tubes 32a and 32b of the fixed terminal portion 30. As a result, the circuit section 20 on which the dielectrically broken device under test 1 is mounted is cut off.
When the drawing is completed, the planar moving part 81A is slightly moved together with the moving terminal part 40, and the holding groove 46 of the moving terminal part 40 is positioned directly above the extending part 11b so that the holding groove 46 of the moving terminal part 40 is aligned with the extending part 11b. make it stop. Subsequently, the vertically moving body 82z is lowered in the vertical (Z) direction, and both sides of the extending portion 11b are inserted into the holding groove 46 of the moving side terminal portion 40. As a result, the movable terminal section 40 is held on the extending portion 11b of the test board 10 with the switching members 42a and 42b pulled out from the sheath tubes 32a and 32b of the fixed terminal section 30.

When the movable terminal portion 40 is held in the extended portion 11b of the test board 10 in this state, the electromagnet 86a of the end effector 86 is de-energized and loses its magnetic force. Then, the vertically moving body 82z is further pulled up together with the end effector 86 while leaving the moving side terminal portion 40 on the extending portion 11b. In this way, the end effector 86 is separated from the catch portion 41d of the movable terminal portion 40. When the vertically moving body 82z is pulled upward (or while being pulled up), the planar moving part 81A returns to the home position, which is the starting point.

As described above, the vertically moving body 82z rises, the switching members 42a and 42b are pulled out from the sheath tubes 32a and 32b of the fixed side terminal section 30, and the circuit section 20 on which the dielectrically broken device under test 1 is mounted is removed. If it is necessary to continue the test after the circuit is turned off, the high voltage generator 60 is energized again to restart the dielectric breakdown test. This operation is repeated to perform the insulation performance test on the required number or all the numbers. In addition, as a device configuration that does not include the circuit section disconnection mechanism section 80, the work of pulling out the moving side terminal section 40 may be carried out by an operator. Even in this case, there are advantages in that the work load is reduced by preventing contamination by the insulating oil 100 and simplifying the circuit breaking process.

Although a three-dimensional XYZ table is used as an example of the circuit section cut-off mechanism section 80, the present invention is not limited to this, and a robot arm 83 capable of three-dimensional movement can also be used.
The robot arm 83 includes a serial link type and a parallel link type, and the serial link type includes various types such as a coordinate axis type and a multi-joint type. Here, an explanation will be given using an articulated robot arm as an example.
The multi-jointed robot arm that constitutes the circuit section cutoff mechanism section 80 is a device whose multi-joints are driven by servo motors. An end effector 86 is attached to the tip of the arm.
In an articulated robot arm, servo motors at the joints connecting the arms are driven to perform operations similar to those of the three-dimensional XYZ table.

In the above example, the electromagnet 86a is used as the end effector 86. However, for example, when the suction cup 86b is attached and the movable terminal section 40 is moved, the suction cup 86b is used to catch the catch portion 41d of the movable terminal section 40. After the suction cup 86b has been moved, air may be sent into the suction cup 86b to separate the suction cup 86b from the catch portion 41d.

As yet another example of the end effector 86, it is also possible to use a scissor member 86c. In the case of the scissors member 86c, the movable side terminal portion 40 is moved across the catch portion 41d, and when the movement is finished, the scissor member 86c is opened to remove the scissor member 86c from the catch portion 41d.

A: Insulation performance testing device for semiconductor elements, 1: Element under test, 1a: Element under test where dielectric breakdown occurred, 3: Constant temperature chamber, 5: Holding groove, 6: Protrusion, 7: First conductor bar, 7h: Conductive hole , 8: second conductor bar, 8h: conduction hole, 10: test board, 11: board main body, 11a: main body part, 11b: extension part, 13: handle, 13k: locking part, 14a: first conduction pin , 14b: second conduction pin, 20: circuit section, 21: opening/closing mechanism section, 30: fixed side terminal section, 30a: first fixed side terminal member, 30b: second fixed side terminal member, 31a/31b: connection continuity part, 32a and 32b: sheath tube, 40: moving side terminal part, 41: terminal main body, 41a: central member, 41b and 41c: side member, 41d: catch part, 42a and 42b: switching member, 45: guide groove, 46: Holding groove, 54: Current limiting resistor, 55: Socket, 55a: First terminal, 55b: Second terminal, 56: Current detection resistor, 57a: High voltage application side conductor, 57b: Low voltage side conductor, 58a: High voltage application side relay section, 58b: Low voltage side relay section, 60: High voltage generator, 70: Multi-channel voltage waveform monitor, 80: Circuit cutoff mechanism section, 81A: Planar moving section, 81B: Vertical direction moving section , 81x: X direction rail, 81y: Y direction rail, 81z: Z direction rail, 82x: X direction moving body, 82y: Y direction moving body, 82z: Vertical direction moving body, 83: 3D robot arm, 86: End Effector, 86a: Electromagnet, 86b: Suction cup, 86c: Scissor member, 90: Earth, 100: Insulating oil

Claims (11)

A constant temperature bath 3 filled with insulating oil 100,
The circuit section 20 is disposed in the thermostatic chamber 3 and includes a semiconductor device as the device under test 1 and a current detection resistor 56 connected to the device under test 1. A test board 10 immersed in insulating oil 100 to a submerged position;
a high voltage generator 60 that applies a high voltage to the device under test 1 via the circuit section 20;
an opening/closing mechanism section 21 that is provided in the circuit section 20 and connects and disconnects the circuit section 20;
The voltage waveform of each current detection resistor 56 of a plurality of circuit sections 20 provided on one or more test boards 10 is monitored, the voltage waveform is stored, and dielectric breakdown is caused based on the position information of the stored voltage waveform. In the insulation performance testing apparatus A for semiconductor devices, which is configured with a multi-channel voltage waveform monitor 70 that specifies the device under test 1a,
The opening/closing mechanism part 21 includes a fixed terminal part 30 provided in the circuit part 20 and provided with first and second fixed terminal members 30a and 30b immersed in insulating oil 100, and Insulation performance test for semiconductor devices, characterized in that it is comprised of a movable side terminal part 40 that approaches and separates from the terminal members 30a and 30b and connects and disconnects the first and second fixed side terminal members 30a and 30b. Device. A catch portion 41d provided on the head of the movable terminal portion 40 and for separating the movable terminal portion 40 from the first and second fixed terminal portions 30a and 30b is coated with insulating oil 100. 2. The insulation performance testing device for semiconductor devices according to claim 1, wherein the device is provided so as to protrude above the oil level of the semiconductor device. It further includes a circuit section cutoff mechanism section 80 that operates the opening/closing mechanism section 21 to electrically disconnect the circuit section 20,
The circuit section interrupting mechanism section 80 moves the corresponding movable side terminal section 40 according to the positional information of the dielectrically broken device 1a detected by the multi-channel voltage waveform monitor 70, and 3. The insulation performance testing device for semiconductor devices according to claim 1, wherein the fixed side terminal members 30a and 30b are cut off. The first and second fixed side terminal members 30a and 30b of the fixed side terminal section 30 are composed of cylindrical members,
The insulator for semiconductor devices according to claim 1 or 2, wherein the movable side terminal section 40 is constituted by a pin-shaped member that can be inserted into and removed from the first and second fixed side terminal members 30a and 30b. Performance testing equipment. The circuit section cutoff mechanism section 80 is
a plane moving unit 81A that moves within a plane that covers the placement area of the test board 10;
a vertical movement section 81B that is provided on the plane movement section 81A and moves in the vertical direction;
It is attached to the vertically moving part 81B, holds the movable side terminal part 40 of the opening/closing mechanism part 21, and moves the movable side terminal part 40 while being held, and the first and second fixed side terminal members 30a and 30b and an end effector 86 that separates the movable side terminal portion 40 from the end effector 86 and blocks a connection between the first and second fixed side terminal members 30a and 30b. Insulation performance test equipment. The plane moving part 81A is
An X-direction rail 81x arranged along one side of the arrangement area of the test board 10;
an X-direction moving body 82x that moves along the X-direction rail 81x;
a Y-direction rail 81y mounted on the X-direction moving body 82x and arranged orthogonally to the X-direction rail 81x;
and a Y-direction moving body 82y that moves along the Y-direction rail 81y,
The vertical movement section 81B is
A vertical rail 81z vertically installed on the Y-direction moving body 82y,
6. The insulation performance testing apparatus for semiconductor devices according to claim 5, further comprising a vertical moving body 82z that moves along the vertical rail 81z. 6. The insulation performance testing apparatus for semiconductor devices according to claim 5, wherein the planar moving section 81A and the vertical moving section 81B are comprised of a robot arm 83 capable of three-dimensional movement. The end effector 86 of the circuit interrupting mechanism section 80 is composed of an electromagnet 86a,
6. The insulation performance testing device for semiconductor devices according to claim 5, wherein a catch portion 41d of the movable terminal portion 40 held by the end effector 86 is made of a magnetic material. 6. The insulation performance testing device for semiconductor devices according to claim 5, wherein the end effector 86 of the circuit section interrupting mechanism section 80 includes a suction cup 86b that attracts the catch portion 41d of the movable terminal section 40. 6. The insulation performance testing device for semiconductor devices according to claim 5, wherein the end effector 86 of the circuit section interrupting mechanism section 80 includes a scissor member 86c for pinching the catch section 41d of the movable side terminal section 40. The test board 10 includes a main body portion 11a on which the circuit section 20 is installed, and an extending portion 11b extending upward from the upper end thereof,
The movable terminal portion 40 of the opening/closing mechanism portion 21 is provided with a guide groove 45 into which the extension portion 11b is inserted and a holding groove 46 extending upward from the lower end of the movable terminal portion 40.
The guide groove 45 is longer than the holding groove 46 and is configured such that the extending portion 11b is inserted when the movable terminal portion 40 contacts the fixed terminal portion 30,
According to claim 1 or 2, the holding groove 46 is configured such that the extending portion 11b is inserted so that the movable terminal portion 40 is kept separated from the fixed terminal portion 30. The insulation performance testing device for semiconductor elements described above.

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