WO2021088187A1

WO2021088187A1 - Press-fit power module inspection system and inspection method

Info

Publication number: WO2021088187A1
Application number: PCT/CN2019/123834
Authority: WO
Inventors: 刘洋; 敖日格力; 叶怀宇; 张国旗
Original assignee: 深圳第三代半导体研究院
Priority date: 2019-11-05
Filing date: 2019-12-06
Publication date: 2021-05-14
Also published as: CN112782552B; CN112782552A

Abstract

A press-fit power module inspection system, comprising: a press-fit power module, a power supply unit, a signal acquisition unit, a control unit, a driving unit, and an action unit. The press-fit power module comprises at least one power module layer; the power module layer comprises n*m sub-unit chips, and n signal transmission strips each used for connecting the gates of a row of the sub-unit chips; the signal transmission strips comprise m layers of stacked integrated signal transmission sub-strips; each signal transmission sub-strip is used for transmitting a signal of one sub-unit chip. The press-fit power module inspection system solves the technical problem of being difficult to independently troubleshoot sub-unit chips in an existing press-fit power module, and can implement independent control and inspection of the sub-unit chips in the power module.

Description

Crimp type power module detection system and detection method

Technical field

Semiconductor field, specifically related to the preparation of power electronic devices

Background technique

The invention designs a crimping device based on a multi-layer PCB board that is easy to detect, and this device can conveniently test the position of the failure subunit of the crimping device.

In the traditional welded power module, the stray parameters of the circuit are relatively large, and a large voltage spike will be generated during the shutdown process and accompanied by a certain amount of electromagnetic interference. When the power system puts forward higher requirements for power levels and requires more chips to be connected in parallel, the parasitic parameters of the chip gate, emitter, and collector and their differences will be further increased, and the voltage overshoot will be aggravated. Switching losses, and lead to a great imbalance of the current, thereby reducing the reliability of the device. Compared with welded power modules, crimped power modules have the advantages of high voltage, large current, low stray inductance, fast switching speed, and double-sided heat dissipation. Therefore, crimped power modules have become the mainstream of semiconductor devices in HVDC transmission. select.

However, since the crimping type power module uses pressure to connect the sub-units in parallel and crimping together, short-circuit failures often occur during use. However, in the traditional device, all chips are connected in parallel. Once there is a short-circuit inside the chip, the entire device will be damaged. Invalidate. However, it is very difficult for traditional crimping devices to eliminate failed chips, and each chip needs to be taken out separately for wafer-level testing, and the entire testing process is very cumbersome.

Summary of the invention

In order to overcome the shortcomings of the prior art and solve the technical problem that the internal subunit chips of the crimping power module are difficult to independently troubleshoot the fault, the present invention can realize a crimping power module detection system and a detection method that can be independently controlled and detected inside the power module.

A crimping type power module detection system, including: crimping type power module, power supply unit, signal acquisition unit, control unit, driving unit, action unit;

The crimping type power module includes at least one power module layer, the power module layer includes n*m sub-unit chips, n signal transmission bars for connecting the gates of the sub-unit chips in each row, and the signal transmission bar It includes m-layer stacked integrated signal transmission sub-strips, and each signal transmission sub-strip is used to transmit a signal of a sub-unit chip.

Preferably, the control unit is used to send a control signal to the output terminal of the gate control port of the designated sub-unit chip; and determine whether the sub-unit chip is faulty according to the signal collected by the signal acquisition unit.

Preferably, the judging whether the sub-unit chip is faulty according to the signal collected by the signal acquisition unit is: adopting the driving unit to output at least two different gate driving voltages to the designated sub-unit chip, and judging whether the current of the sub-unit chip is controlled by the gate. Change, if it changes, the sub-unit chip is not short-circuited, if it does not change, the sub-unit chip is short-circuited.

Preferably, the signal acquisition unit is used to collect voltage and current signals through AD signals; the power supply unit is a voltage and current source; the sub-unit chip includes a power chip and an FRD chip, and the power chip includes a MOSFET chip or an IGBT chip .

Preferably, the action unit includes a motor, and the motor removes the faulty sub-unit chip under the control of the control unit.

A method for detecting a crimping power module includes:

S1: The control unit is used to control the driving unit to output the first driving voltage V _C1 _{to the designated at least one sub-unit chip C xy} ; the first collection voltage value V ₁ and the first collection of the sub-unit chip under the first driving voltage V _{C1 are collected} Current value I ₁ ; 1<x<n, <1<y<m;

S2: The control unit is used to control the driving unit to output _{a second driving voltage V C2 that} is different from the voltage value of the _{first driving voltage V C1} _{to the designated sub-unit chip; the first driving voltage V C2} of the sub-unit chip C _xy under the first driving voltage V C2 is collected 2. Collecting the voltage value V ₂ and the second collecting current value I ₂ ;

S3: Compare the first collected voltage value V ₁ with the second collected voltage value V ₂ , and the first collected current value I ₁ with the second collected current value I ₂ , and judge whether the sub-unit chip C _xy is faulty.

Preferably, the S3 judging whether the sub-unit chip C _xy has a fault is: if the first collected voltage value V _{1 is} equal to the second collected voltage value V ₂ , the sub-unit chip is short-circuited.

Preferably, the detection method further includes S4: if the sub-unit chip C _xy fails, the control unit is used to control the action unit to remove the failed sub-unit chip C _xy .

Preferably, the S3 includes: _{repeating S2T times with T different driving voltages V Cj} , correspondingly collecting T j-th collected voltage values V _j and j-th collected current values I _j , 1<j<T, compare arbitrarily Two j-th collected voltage values V _j and any two j-th collected current values I _j .

Preferably, the step range of the T different driving voltages V _Cj is 0.5-5V, and the time interval for collecting the T j-th collected voltage value V _j and the j-th collected current value I _j ranges from 20 ns to 200 us. .

The crimping power detection module system of the present invention uses a multi-layer signal transmission strip when the gate of the sub-unit chip of the crimping type power module to be detected is led out, and the copper-clad surface of each layer of the external test terminal leaks in sequence. This special The signal transmission bar can realize the drive of the specified chip in the device, and can realize the independent drive of one or more sub-unit chips or the troubleshooting and replacement of the specified one or more sub-unit chips.

Description of the drawings

Figure 1 is a schematic diagram of a crimping power module provided in the first embodiment

Figure 2 is a schematic diagram of the crimping power module provided in the first embodiment

Fig. 3 is a schematic diagram of the detection system of the crimping power module detection system provided in the first embodiment

Fig. 4 is a flow chart of the detection method of the crimping power module detection system provided in the first embodiment

Detailed ways

The specific implementation of the present invention is described in detail below. It is necessary to point out that the following implementation is only used for further description of the present invention, and should not be understood as a limitation of the scope of protection of the present invention. Those skilled in the art will discuss the present invention based on the above-mentioned content of the present invention. Some non-essential improvements and adjustments made still belong to the protection scope of the present invention.

Example one

This embodiment provides a crimping type power module detection system, as shown in Figs. 1-3.

The crimping type power module detection system provided by this embodiment is shown in FIG. 3, and includes: crimping type power module, power supply unit, signal acquisition unit, control unit, driving unit, and action unit.

As shown in Figure 1, the crimping power module of this embodiment includes a chip, FR4 board, copper block, and copper plate arranged in order from top to bottom, and the upper end cover is separated into two layers; the bottom layer is made of separate copper One piece is embedded in the FR4 board and connected to the collector (C pole) of each chip, and the end cover is covered with an insulating outer frame, and the copper plate is placed on the top layer as the end cover; the gate is led out using a multilayer PCB board, and the external test terminals The copper-clad surface of the multi-layer PCB board leaks out in turn, this special PCB board can realize the drive of the specified chip in the device.

As shown in FIG. 2, it is the signal transmission strip in the crimping power module provided by this embodiment, which includes five layers of PCB strips with decreasing length from top to bottom bonded together. The preparation method of the signal transmission strip includes: according to the distance between the five sub-unit chips in each row and the outer edge of the power module, cutting five single strips with a length corresponding to the distance one-to-one on the PCB. If the number of sub-unit chips in each row is other, or each signal transmission bar is used to transmit the signal of the sub-unit chips in each column, the number of single PCBs is based on the number of sub-unit chips in each column or row of the press-fit power chip determine. Figure 5 shows the prepared single-layer PCB. The PCB is staggered and bonded by glue, and the connection with the gate signal of the chip and the outermost lead part are leaked during bonding to facilitate the contact of the thimble. Glue can use silicone glue, phenolic resin glue, urea-formaldehyde resin glue, temperature-resistant epoxy glue, polyimide glue, etc.

The power supply unit is a voltage and current source, which is used to supply power to the crimping power module; the action unit includes a motor, which is used to replace the faulty sub-unit chip under the control of the control unit.

The signal acquisition unit collects the voltage value and current value of the sub-unit chip.

The control unit is used to send a control signal to the output terminal of the gate control port of the designated sub-unit chip; and judge whether the sub-unit chip is faulty according to the signal collected by the signal acquisition unit. Judging whether the sub-unit chip is faulty is: using the driving unit to output at least two different gate drive voltages to the specified sub-unit chip, and judging whether the current of the sub-unit chip is changed by the gate control, if it changes, the sub-unit chip is not short-circuited, If it does not change, the sub-unit chip is short-circuited. The control unit also controls the motor to remove the faulty sub-unit chip.

This embodiment also provides a method for detecting a crimping power module, as shown in FIG. 4.

Step 1: Start.

Step 2: Control the single-chip microcomputer to output control signals to the gate control port of the designated sub-unit chip.

Step 3: The single-chip microcomputer controls the connection port of the collector (C pole) of the corresponding sub-unit chip, and the given voltage is 5V.

Step 4: Real-time detection of the voltage and current values of the collector emitter (CE electrode) of the sub-unit chip.

Step 5: Adjust the gate drive voltage from 0V to 15V with a step length of 1V and a measurement interval of 200us.

Step 6: Determine whether the detected collector-emitter (CE electrode) voltage and current are changed under the control of the grid. If it changes, it means that the sub-unit chip has no short-circuit fault, and the single-chip microcomputer is used to control the measurement of the next set of designated sub-unit chips; if it does not change, it means that the sub-unit chip whose current and voltage has not changed in the above-mentioned sub-unit chip has a short-circuit fault.

Step 7: Use a single-chip microcomputer to control the motor to remove the sub-unit chip that has a short-circuit fault.

In the crimping power detection module system of this embodiment, the multi-layer signal transmission strip is used when the new product grid of the sub-unit of the crimping power module to be tested is led out, and the copper-clad surface of each layer of the external test terminal leaks in turn. The special signal transmission bar can realize the driving of the specified chip in the device, and can realize the independent driving of one or more sub-unit chips or the troubleshooting and replacement of the specified one or more sub-unit chips.

Although the exemplary embodiments of the present invention have been described for illustrative purposes, those skilled in the art will understand that they can be modified in form and details without departing from the scope and spirit of the invention disclosed in the appended claims. Various modifications, additions, substitutions, etc. are made, and all these changes shall fall within the protection scope of the appended claims of the present invention, and the various steps in the various departments and methods of the products claimed by the present invention can be combined in any combination. Forms are combined together. Therefore, the description of the embodiments disclosed in the present invention is not intended to limit the scope of the present invention, but to describe the present invention. Accordingly, the scope of the present invention is not limited by the above embodiments, but is defined by the claims or their equivalents.

Claims

A crimping type power module detection system, which is characterized by comprising: crimping type power module, power supply unit, signal acquisition unit, control unit, driving unit, and action unit;

The crimping type power module includes at least one power module layer, the power module layer includes n*m sub-unit chips, n signal transmission bars for connecting the gates of the sub-unit chips in each row, and the signal transmission bar It includes m-layer stacked integrated signal transmission sub-strips, and each signal transmission sub-strip is used to transmit a signal of a sub-unit chip.
The crimping power module detection system according to claim 1, wherein the control unit is used to send a control signal to the output terminal of the gate control port of the specified sub-unit chip; and determine the sub-unit according to the signal collected by the signal collection unit Whether the unit chip is faulty.
The crimping power module detection system according to claim 2, wherein the judging whether the sub-unit chip is faulty according to the signal collected by the signal collecting unit is: using the driving unit to output at least two different types of chips to the specified sub-unit chip. To determine whether the current of the sub-unit chip is changed by the gate control, if it changes, the sub-unit chip is not short-circuited, if it does not change, the sub-unit chip is short-circuited.
The crimp-type power module detection system according to claim 1, wherein the signal acquisition unit is used to collect voltage and current signals through AD signals; the power supply unit is a voltage and current source; and the sub-unit chip includes Power chips and FRD chips. The power chips include MOSFET chips or IGBT chips.
The crimping type power module detection system according to claim 1, wherein the action unit comprises a motor, and the motor removes the faulty sub-unit chip under the control of the control unit.
A crimp-type power module detection method using the crimp-type power module detection system according to claims 1-5, characterized in that it comprises:

S1: The control unit is used to control the driving unit to output the first driving voltage V C1 to the designated at least one sub-unit chip C xy ; the first collection voltage value V 1 and the first collection of the sub-unit chip under the first driving voltage V C1 are collected Current value I 1 ; 1<x<n, <1<y<m;

S2: The control unit is used to control the driving unit to output a second driving voltage V C2 that is different from the voltage value of the first driving voltage V C1 to the designated sub-unit chip; the first driving voltage V C2 of the sub-unit chip C xy under the first driving voltage V C2 is collected 2. Collecting the voltage value V 2 and the second collecting current value I 2 ;

S3: Compare the first collected voltage value V 1 with the second collected voltage value V 2 , and the first collected current value I 1 with the second collected current value I 2 , and judge whether the sub-unit chip C xy is faulty.
The crimping type power module detection method according to claim 6, wherein the S3 judging whether the sub-unit chip C xy has a fault is: if the first collected voltage value V 1 is equal to the second collected voltage value V 2 Then the sub-unit chip is short-circuited.
The crimping type power module detection method according to claim 6, characterized in that the detection method further comprises S4: if the sub-unit chip C xy fails, the control unit is used to control the action unit to remove the failed sub-unit chip C xy .
The crimping type power module detection method according to claim 6, wherein the S3 comprises: using T different driving voltages V Cj to repeat S2T times, correspondingly collecting T j-th collected voltage values V j and The j-th collected current value I j , 1<j<T, compare any two j-th collected voltage values V j and any two j-th collected current values I j .
The crimping type power module detection method according to claim 9, wherein the step range of the T different driving voltages V Cj is 0.5-5V, and the collected T j-th collected voltage values V j The time interval between and the j-th collected current value I j ranges from 20ns to 200us.