CN103579032B - The method of testing of power semiconductor modular packaging technology and system - Google Patents
The method of testing of power semiconductor modular packaging technology and system Download PDFInfo
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- CN103579032B CN103579032B CN201210254531.4A CN201210254531A CN103579032B CN 103579032 B CN103579032 B CN 103579032B CN 201210254531 A CN201210254531 A CN 201210254531A CN 103579032 B CN103579032 B CN 103579032B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/10—Measuring as part of the manufacturing process
- H01L22/12—Measuring as part of the manufacturing process for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/30—Structural arrangements specially adapted for testing or measuring during manufacture or treatment, or specially adapted for reliability measurements
- H01L22/32—Additional lead-in metallisation on a device or substrate, e.g. additional pads or pad portions, lines in the scribe line, sacrificed conductors
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
- H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
- H01L2224/85—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a wire connector
- H01L2224/859—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a wire connector involving monitoring, e.g. feedback loop
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- Manufacturing & Machinery (AREA)
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- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Investigating Or Analyzing Materials Using Thermal Means (AREA)
- Testing Of Individual Semiconductor Devices (AREA)
Abstract
The invention discloses method of testing and system, the method for testing of a kind of power semiconductor modular aluminum wire bonding technique and the system of a kind of power semiconductor modular chip bonding process, and include method of testing and the system of the packaging technology of chip bonding process and aluminum wire bonding process test.Present invention electric heating device simulated condition, by applying pulse voltage/electric current to electric heating device, and/or apply the measured piece heating after loop test voltage/current welds to chip, or apply running voltage/electric current to the measured piece after aluminum wire bonding, and/or apply loop test voltage/current, use thermal infrared imager that measured piece is carried out thermo parameters method test；Whether the thermo parameters method situation according to measured piece or its aluminum wire bonding point has exception, determines that chip bonding process and/or aluminum wire bonding technique are the most defective.Achieve the dynamic monitoring under actual working conditions of chip bonding process and/or aluminum wire bonding technique, reduce testing cost.
Description
Technical field
The present invention relates to semiconductor test technology, particularly to the test side of power semiconductor modular packaging technology
Method and system.
Background technology
At present, insulation bipolar transistor (IGBT) constant power semiconductor device also exists in encapsulation process
Working procedures: chip welding aluminum wire bonding welding copper soleplate and DBC install shell and fill
Note Silica hydrogel glue curing installs cover plate, screw etc..Wherein, the most key technique is chip
Welding and the bonding of aluminum steel, the effective quality detecting this two big critical process, it is clear that had become as and guaranteed
One of necessary program that final whole module normally works.
For the detection of the technique of chip welding, X-ray is mainly used to detect both at home and abroad in terms of commercial production
Technology detects, and this detection is the image-forming principle utilizing X-ray, and X-ray is mapped to the core welded
On sheet, by the way of imaging, observing whether weld has cavity, if there being cavity, illustrating to weld bad.
For the detection of the technique of aluminum wire bonding, two ways is had to detect in terms of commercial production, a kind of
As the detection method of chip bonding process, X-ray detection technique is used to detect.Another kind is logical
Crossing the mode of tensile test, the pulling force that the aluminum steel after detection bonding can bear, according to its pulling force born
Power judges the quality of the technique of aluminum wire bonding.
Generally, X-ray detection technique needs much more expensive equipment, and is to go inspection from static angle
Surveying the quality of technique, this also can not represent such welding procedure and the aluminum wire bonding actual feelings under operating mode
Condition.And use the mode of tensile test to detect aluminum wire bonding and also have same problem.
Summary of the invention
In view of this, a kind of power semiconductor modular chip bonding process of offer is provided
Method of testing and system, the method for testing of a kind of power semiconductor modular aluminum wire bonding technique and system, and
Including chip bonding process and the method for testing of the packaging technology of aluminum wire bonding process test and system, to realize
Chip bonding process and/or the test under actual working conditions of aluminum wire bonding technique.
For reaching an aspect of above-mentioned purpose, the invention provides a kind of power semiconductor modular chip welding
The method of testing of technique and system.
The method of testing of the power semiconductor modular chip bonding process that the present invention provides, at power semiconductor mould
The chip bonding process of block complete after perform following steps:
A, chip bonding process is completed after measured piece be placed on electric heating device, make the two closely paste
Merge fixing；
B, simulation actual condition apply different pulse voltage/electric currents to electric heating device；And/or apply to follow
Ring test voltage/current；
C, employing thermal infrared imager carry out thermo parameters method test to measured piece；
Whether D, thermo parameters method situation according to measured piece have exception, determine whether chip bonding process has
Defect.
It is preferred that described step D is: judge whether the temperature field of measured piece has and make a reservation for higher than mean temperature
The point of the number of degrees, determines that the chip position welding procedure that this point is corresponding has cavity blemish.
It is preferred that described predetermined number of degrees with respect could be arranged to 1-25 degree Celsius.
It is preferred that in advance experimental results is added up, set up thermo parameters method abnormal conditions and chip
Welding procedure defect and quantifying defects value corresponding relation data base；Described step D is: in the database
Search the thermo parameters method situation of described measured piece, if found, it is determined that have the chip of its correspondence to weld
Defective workmanship, and provide quantifying defects value.
It is preferred that the method monitors electric current and the voltage of electric heating device the most in real time, according to current flow
And voltage, adjust the pulse voltage that electric heating device is applied.
It is preferred that the method uses chiller that measured piece is carried out radiating and cooling further, and monitor in real time
The temperature of measured piece, according to current temperature value, adjusts the running parameter of chiller.
The test system of the method for testing realizing said chip welding procedure that the present invention provides, including: power supply
Unit, control unit, high-current switch module and driver element thereof, electric heating device, thermal infrared imager and
Host computer；
Described control unit is respectively connected with power subsystem, described driver element and host computer, this power subsystem
Also being connected with high-current switch module, this driver element is also connected with high-current switch module, described big electric current
Switch module is also connected with electric heating device；Described host computer is also connected with thermal infrared imager；
Measured piece after chip bonding process completes is placed on electric heating device, and the two fits tightly fixing；
The test parameter of the different operating modes that described control unit sends according to host computer, by controlling power subsystem
And driver element, controlling described high-current switch module is that electric heating device applies different pulse voltage/electricity
Stream；And/or apply loop test voltage/current；
Described host computer produces the test parameter of different operating mode and is sent to control unit, and receives thermal infrared imager
The temperature data of the measured piece sent, it is thus achieved that the thermo parameters method characteristic of measured piece, according to the temperature of measured piece
Whether field distribution situation has exception, determines that chip bonding process is the most defective.
It is preferred that this system also includes the data storage device being connected with host computer；Described data storage device,
Prestore thermo parameters method abnormal conditions and chip bonding process defect and quantifying defects value corresponding relation number
According to storehouse；Described host computer searches the thermo parameters method situation of described measured piece in the database, if looked into
Find, it is determined that have the chip bonding process defect of its correspondence, and provide quantifying defects value.
It is preferred that this system farther includes current sensor and the voltage sensor being connected with electric heating device
Device；Electric current and the voltage of electric heating device are sent to control by described current sensor and voltage sensor in real time
Unit；Described control unit according to current flow and voltage, adjusts the arteries and veins applying electric heating device further
Rush voltage/current and/or loop test voltage/current.
It is preferred that this system farther includes the chiller being arranged under measured piece and the temperature being attached thereto
Sensor；Control unit receives the temperature signal that temperature sensor sends further, according to the temperature of measured piece,
Sending running parameter to chiller, controlling chiller is measured piece cooling.
It is preferred that described control unit connect have warning circuit, control unit electric heating device electric current and
/ or during electric voltage exception, turn off electric heating device by driver element, and control warning circuit send sound and/
Or visual alarm.
For reaching second aspect of above-mentioned purpose, the invention provides a kind of power semiconductor modular aluminum steel key
Close method of testing and the system of technique.
The method of testing of the power semiconductor modular aluminum wire bonding technique that the present invention provides, at power semiconductor mould
The aluminum wire bonding technique of block complete after perform following steps:
A, simulation actual condition aluminum wire bonding technique is completed after measured piece apply different running voltage/
Electric current；And/or apply loop test voltage/current；
B, employing thermal infrared imager click on trip temperature field distribution test to the aluminum wire bonding of measured piece；
Whether c, thermo parameters method according to the aluminum wire bonding point of measured piece have exception, determine aluminum wire bonding work
Skill is the most defective.
It is preferred that described step c is: judge whether the aluminum wire bonding point temperature field of measured piece has higher than flat
All the point of temperature predetermined number of degrees with respect, determines that the bonding technology of the aluminum wire bonding point that this point is corresponding has crack defect.
It is preferred that described predetermined number of degrees with respect could be arranged to 1-25 degree Celsius.
It is preferred that add up experimental results in advance, the thermo parameters method setting up aluminum wire bonding point is different
Reason condition and aluminum wire bonding defective workmanship and quantifying defects value corresponding relation data base；Described step c is:
Described data base searches the thermo parameters method situation of the aluminum wire bonding point of described measured piece, if found,
Then determine the aluminum wire bonding defective workmanship having its correspondence, and provide quantifying defects value.
It is preferred that the method monitors electric current and the voltage of measured piece the most in real time, according to current flow and electricity
Pressure, adjusts the running voltage/electric current and/or loop test voltage/current applying measured piece.
It is preferred that the method uses chiller that measured piece is carried out radiating and cooling further, and monitor in real time
The temperature of measured piece, according to current temperature value, adjusts the running parameter of chiller.
The test system of the method for testing realizing described aluminum wire bonding technique that the present invention provides, including: power supply
Unit, control unit, high-current switch module and driver element, thermal infrared imager and host computer；
Described control unit is respectively connected with power subsystem, described driver element and host computer, this power subsystem
Also being connected with high-current switch module, this driver element is also connected with high-current switch module, described big electric current
Measured piece after switch module is completed with bonding technology by lead-in wire is connected；Described host computer also with infrared thermal imagery
Instrument is connected；
The test parameter of the different operating modes that described control unit sends according to host computer, by controlling power subsystem
And driver element, control described high-current switch module and measured piece applied different running voltage/electric currents,
And/or apply loop test voltage/current；
Described host computer produces the test parameter of different operating mode and is sent to control unit, and receives thermal infrared imager
The temperature data of the aluminum wire bonding point of the measured piece sent, it is thus achieved that the temperature field minute of the aluminum wire bonding point of measured piece
Whether cloth characteristic, have exception according to the thermo parameters method situation of the aluminum wire bonding point of measured piece, determine aluminum steel key
Close technique the most defective.
It is preferred that this system also includes the data storage device being connected with host computer；Described data storage device,
Prestore thermo parameters method abnormal conditions and aluminum wire bonding defective workmanship and quantifying defects value corresponding relation number
According to storehouse；Described host computer searches the thermo parameters method of the aluminum wire bonding point of described measured piece in the database
Situation, if found, it is determined that has the aluminum wire bonding defective workmanship of its correspondence, and provides quantifying defects value.
It is preferred that this system farther includes current sensor and the voltage sensor being connected with measured piece；Institute
State current sensor and electric current and the voltage of measured piece are sent to control unit by voltage sensor in real time；Described
Control unit further according to current flow and voltage, adjust running voltage/electric current that measured piece is applied and/
Or loop test voltage/current.
It is preferred that this system farther includes the chiller being arranged under measured piece and the temperature being attached thereto
Sensor；Control unit receives the temperature signal that temperature sensor sends further, according to the temperature of measured piece,
Sending running parameter to chiller, controlling chiller is measured piece cooling.
It is preferred that described control unit connect have warning circuit, control unit measured piece electric current and/or
During electric voltage exception, turn off measured piece by driver element, and control warning circuit and send sound and/or light and report to the police
Signal.
For reaching the 3rd aspect of above-mentioned purpose, the invention provides a kind of power semiconductor modular encapsulation work
The method of testing of skill and system.
The method of testing of the power semiconductor modular packaging technology that the present invention provides, completes at chip bonding process
The testing procedure of the chip bonding process that rear execution is above-mentioned；Above-mentioned aluminum is performed after aluminum wire bonding technique completes
The testing procedure of line bonding technology.
The test system of the power semiconductor modular packaging technology that the present invention provides, including above-mentioned chip welding
The test system of technique and the test system of aluminum wire bonding technique.
As seen from the above technical solutions, present invention electric heating device simulated condition, by electric heater
Part applies pulse voltage/electric current, and/or applies the measured piece after loop test voltage/current welds to chip
Heating, or simulated condition, apply running voltage/electric current to the measured piece after aluminum wire bonding, and/or execute
Add loop test voltage/current, use thermal infrared imager that measured piece is carried out thermo parameters method test；Obtain
Measured piece or the thermo parameters method characteristic of its aluminum wire bonding point, according to measured piece or the temperature of its aluminum wire bonding point
Whether field distribution situation has exception, determines that chip bonding process and/or aluminum wire bonding technique are the most defective.
Achieve the test under actual working conditions of chip bonding process and/or aluminum wire bonding technique, with existing skill
Art is compared, it is not necessary to uses expensive X-ray equipment, reduces testing cost.
It addition, the present invention to after electric heating device or aluminum wire bonding measured piece apply loop test voltage/
In the case of electric current, it is possible to realize on-line monitoring, can be according to temperature field after long loop test
Real-time change, reflection is brought the whole process of destruction, thus realizes dynamic monitoring by defect.
Accompanying drawing explanation
Fig. 1 is method of testing one preferred embodiment of power semiconductor modular chip bonding process of the present invention
Flow chart；
Fig. 2 is the test system structure figure of the preferred embodiment realizing method of testing shown in Fig. 1；
Fig. 3 is that the method for testing one of the present invention a kind of power semiconductor modular aluminum wire bonding technique is preferably implemented
The flow chart of example；
Fig. 4 is the test system structure figure of the preferred embodiment realizing method of testing shown in Fig. 3.
Detailed description of the invention
Developing simultaneously referring to the drawings, the present invention is described in detail for specific embodiment.
The invention provides method of testing and system, the one of a kind of power semiconductor modular chip bonding process
The method of testing of power semiconductor modular aluminum wire bonding technique and system, and include chip bonding process and aluminum steel
The method of testing of the packaging technology of bonding technology test and system, to realize chip bonding process and/or aluminum steel
Testing under actual working conditions of bonding technology.
Illustrate for embodiment individually below.
First, the method for testing of power semiconductor modular chip bonding process of the present invention is illustrated.
As it is shown in figure 1, the method for testing one of power semiconductor modular chip bonding process of the present invention is preferably implemented
Example comprises the steps:
Step 101, the measured piece after being completed by chip bonding process is placed on electric heating device, makes the two
Fit tightly and fix.
In the present embodiment, measured piece is the DBC module having welded chip.In order to measured piece is heated evenly, can
To use that matches with measured piece size to add thermal resistance or heating member as electric heating device.
Step 102, simulation actual condition applies different pulse voltage/electric currents to electric heating device；And/or
Apply loop test voltage/current.
In the present embodiment, it is also possible to electric current and voltage to electric heating device are monitored in real time, according to currently
Electric current and voltage, adjust the pulse voltage/electric current applying electric heating device；And/or loop test voltage/
Electric current.
The present invention is by applying loop test voltage/current to electric heating device, it is possible to realize on-line monitoring,
Can reflect and brought the whole of destruction according to the real-time change in temperature field by defect after loop test for a long time
Individual process, thus realize dynamic monitoring.
Step 103, uses thermal infrared imager that measured piece is carried out thermo parameters method test.
The thermal infrared imager used in the present embodiment can be existing conventional thermal infrared imager.
Whether step 104, have exception according to the thermo parameters method situation of measured piece, determine chip bonding process
The most defective.
In the present embodiment, two ways can be used to determine that chip bonding process is the most defective.
The first: judge whether the temperature field of measured piece has the point higher than mean temperature predetermined number of degrees with respect, determine
The chip position welding procedure that this point is corresponding has cavity blemish.
In actual application, predetermined number of degrees with respect could be arranged to 1-25 degree Celsius.
The second: in advance great many of experiments test result is added up, set up thermo parameters method abnormal conditions with
Chip bonding process defect and quantifying defects value corresponding relation data base；Search described quilt in the database
Survey the thermo parameters method situation of part, if found, it is determined that there is the chip bonding process defect of its correspondence,
And provide quantifying defects value.
It addition, the present embodiment uses further chiller measured piece is carried out radiating and cooling, and supervise in real time
Survey the temperature of measured piece, according to current temperature value, adjust the running parameter of chiller.
Then, the test system of the method for testing that the present invention realizes upper chip bonding process illustrates.
As in figure 2 it is shown, the test system of the preferred embodiment for realizing method of testing shown in Fig. 1 includes: electricity
Source unit 201, control unit 202, high-current switch module 203 and driver element 204, electric heating device
205, thermal infrared imager 206, host computer 207, data storage device 208, current sensor 209, voltage
Sensor 210, chiller 211, temperature sensor 212 and display unit 213.
Wherein, control unit 202 is respectively connected with power subsystem 201, driver element 204 and host computer 207,
This power subsystem 201 is also connected with high-current switch module 203, this driver element 204 also with high-current switch
Module 203 is connected, and high-current switch module 203 is also connected with electric heating device 205.Host computer 207 is also with red
Outer thermal imaging system 206 is connected.
Measured piece 200 after chip bonding process completes is placed on electric heating device 205, and the two fits tightly
Fixing.In the present embodiment, measured piece is the DBC module having welded chip.In order to measured piece is heated evenly,
Can use that matches with measured piece size to add thermal resistance or heating member as electric heating device.
As in figure 2 it is shown, the test parameter of different operating modes that control unit 202 sends according to host computer 207, logical
Crossing control power subsystem 201 and driver element 204, controlling high-current switch module 203 is electric heating device 205
Apply different pulse voltage/electric currents；And/or apply loop test voltage/current.
As in figure 2 it is shown, the test parameter that host computer 207 can produce different operating mode is sent to control unit 202,
And receive the temperature data of the measured piece 200 that thermal infrared imager sends, it is thus achieved that the thermo parameters method of measured piece 200
Whether characteristic, have exception according to the thermo parameters method situation of measured piece 200, whether determine chip bonding process
Defective.
Set as in figure 2 it is shown, the test system of the present embodiment further comprises the data storage being connected with host computer 207
Standby 208, this data storage device 208, prestore thermo parameters method abnormal conditions and lack with chip bonding process
Fall into and quantifying defects value corresponding relation data base.So, host computer 207 just can be looked in the database
Look for the thermo parameters method situation of described measured piece, if found, it is determined that have the chip Welder of its correspondence
Skill defect, and provide quantifying defects value.Such as: the size in welding cavity.
As in figure 2 it is shown, for the real-time current and the voltage that obtain electric heating device 205, the test of the present embodiment
System further comprises be connected with electric heating device 205 current sensor 209, voltage sensor 210 and with control
The warning circuit (not shown in Fig. 2) that unit 202 processed is connected.
Electric current and the voltage of electric heating device 205 are sent by current sensor 209 and voltage sensor 210 in real time
To control unit 202.Control unit 202, further according to current flow and voltage, adjusts electric heating device
205 pulse voltages applied.Control unit 202 when the electric current of electric heating device 205 and/or electric voltage exception,
Turn off electric heating device by driver element 204 and high-current switch module 203, and control warning circuit and send
Sound and/or visual alarm.
As in figure 2 it is shown, in order to prevent measured piece 200 overheated damaged, and obtain the real-time temperature of measured piece 200
Degree, the test system of the present embodiment further comprises the chiller 211 being arranged under measured piece 200 and phase therewith
Temperature sensor 212 even.Control unit 202 receives the temperature signal that temperature sensor 212 sends further,
According to the temperature of measured piece 200, sending running parameter to chiller 211, controlling chiller 211 is quilt
Survey part 200 to lower the temperature.
As in figure 2 it is shown, in the present embodiment in order to see more intuitively the current current value of electric heating device 205,
Magnitude of voltage and temperature, be provided with display unit 213, for show the current current value of electric heating device 205,
Magnitude of voltage and temperature.It addition, the data such as current current value, magnitude of voltage and temperature of heater element 205 also may be used
Show being sent to host computer 207.
In the present embodiment, control unit 202 can use DSP to realize, and high-current switch module 203 can use
IGBT module realizes, and driver element 204 can be that the driving module that IGBT module is general realizes.Display unit
213 can realize with LED display or LCD display.Chiller 211 can use conventional cooling to fill
Put, can be specifically water cooling plant can also be air cooling equipment, such as: fan.Therefore, control unit 202
The running parameter sent to chiller 211, can be wind speed or the water flow velocity of water cooling plant of fan.Tool
The control mode of body is identical with prior art, repeats no more here.
Hereinafter the work process that this system is concrete is illustrated.
Host computer 207 control software to control unit 202 send the dutycycle of pulse voltage (PWM), frequency,
After the parameters such as source current I, send to control unit 202 and start order.Control unit 202 just produces accordingly
Frequency is input to driver element 204 with the PWM waveform of dutycycle, and driver element 204 drives high-current switch mould
The break-make of block 205, control unit 202 sends instruction to power subsystem 201 and produces the electric current of amplitude and specific simultaneously.
So, when in electric heating device 205 because of electric current circulation just start heating, such heat is just
Can pass to measured piece 200, the present embodiment is on the chip and DBC being welded in DBC module, by passively adding
The mode of heat makes welding chip and DBC heating, and the surface temperature field distribution of such measured piece 200 is by infrared
Thermal imaging system 206 gathers and is sent in host computer 207.
Owing to when chip normally works, temperature must be in certain scope, it is impossible to too high, therefore the present embodiment
By chiller 211, part 200 to be measured is carried out radiating and cooling, with the closed loop that control unit 202 forms temperature
Control.
When carrying out actual test, by searching data base, it is judged that whether measured piece 200 has chip welding to lack
Fall into.Data in data base are to add up great many of experiments test result in advance, it is thus achieved that thermo parameters method
Abnormal conditions and chip bonding process defect and quantifying defects value corresponding relation.
It follows that the method for testing of power semiconductor modular aluminum wire bonding technique of the present invention is carried out specifically
Bright.
As it is shown on figure 3, the method for testing one of power semiconductor modular aluminum wire bonding technique of the present invention is preferably implemented
Example comprises the steps:
Step 301, the measured piece after aluminum wire bonding technique is completed by simulation actual condition applies different work
Voltage/current；And/or loop test voltage/current.The present invention by applying loop test electricity to measured piece
Pressure/electric current, it is possible to realize on-line monitoring, can real-time according to temperature field after long loop test
Change, reflection is brought the whole process of destruction, thus realizes dynamic monitoring by defect.
In the present embodiment, it is also possible to monitor electric current and the voltage of measured piece in real time, according to current flow and voltage,
Adjust the operating current that measured piece is applied.
Step 302, uses thermal infrared imager that the aluminum wire bonding of measured piece clicks on trip temperature field distribution test.
The thermal infrared imager used in the present embodiment can be existing conventional thermal infrared imager.
Whether step 303, have exception according to the thermo parameters method of the aluminum wire bonding point of measured piece, determine aluminum steel
Bonding technology is the most defective.
In the present embodiment, two ways is equally used to determine that aluminum wire bonding technique is the most defective:
The first: judge whether the aluminum wire bonding point temperature field of measured piece has higher than mean temperature predetermined number of degrees with respect
Point, determine that the bonding technology of the aluminum wire bonding point that this point is corresponding has crack defect.
In actual application, predetermined number of degrees with respect could be arranged to 1-25 degree Celsius.
The second: add up great many of experiments test result in advance, sets up the temperature field minute of aluminum wire bonding point
Cloth abnormal conditions and aluminum wire bonding defective workmanship and quantifying defects value corresponding relation data base.Described data base
The thermo parameters method situation of the aluminum wire bonding point of the described measured piece of middle lookup, if found, it is determined that there is it
Corresponding aluminum wire bonding defective workmanship, and provide quantifying defects value.Such as: the size of aluminum wire bonding crackle.
It addition, the present embodiment can also use chiller measured piece is carried out radiating and cooling, and supervise in real time
Survey the temperature of measured piece, according to current temperature value, adjust the running parameter of chiller.
Then, the test system of the method for testing realizing above-mentioned aluminum wire bonding technique is described in detail.
As shown in Figure 4, include for realizing the test system of a preferred embodiment of method of testing shown in Fig. 3: electricity
Source unit 401, control unit 402, high-current switch module 403, driver element 404, thermal infrared imager 405,
Host computer 406, data storage device 407, current sensor 408, voltage sensor 409, chiller 401,
Temperature sensor 411 and display unit 412.
Wherein, control unit 402 is respectively connected with power subsystem 401, driver element 404 and host computer 406.
This power subsystem 401 is also connected with high-current switch module 403, this driver element 404 also with high-current switch
Module 403 is connected.This high-current switch module 403 is by going between the measured piece 400 after completing with bonding technology
Being connected, this 406 host computer is also connected with thermal infrared imager 405.
As shown in Figure 4, the test parameter of the different operating modes that control unit 401 sends according to host computer 406 is logical
Cross control power subsystem 401 and driver element 404, control high-current switch module 403 and measured piece 400 is applied
Different running voltage/electric currents；And/or loop test voltage/current.
Host computer 406 produces the test parameter of different operating mode and is sent to control unit 402, and receives infrared thermal imagery
The temperature data of the aluminum wire bonding point of the measured piece 400 that instrument 405 sends, it is thus achieved that the aluminum wire bonding of measured piece 400
Whether the thermo parameters method characteristic of point, have according to the thermo parameters method situation of the aluminum wire bonding point of measured piece 400
Abnormal, determine that aluminum wire bonding technique is the most defective.
As shown in Figure 4, the present embodiment system also includes the data storage device 407 being connected with host computer 406.
Data storage device 407, prestores thermo parameters method abnormal conditions and aluminum wire bonding defective workmanship and defect
Quantized value corresponding relation data base.So, host computer 406 searches described measured piece 400 in the database
The thermo parameters method situation of aluminum wire bonding point, if found, it is determined that there is the aluminum wire bonding work of its correspondence
Skill defect, and provide quantifying defects value.
As shown in Figure 4, in order to prevent measured piece 400 from crossing stream or overvoltage, and the real-time of measured piece 400 is obtained
Electric current and voltage, the test system of the present embodiment further comprises the current sensor being connected with measured piece 400
408, voltage sensor 409 and the warning circuit (not shown in Fig. 2) that is connected with control unit 402.
Electric current and the voltage of measured piece 400 are sent to control by current sensor 408 and voltage sensor 409 in real time
Unit 402 processed.Control unit 402, further according to current flow and voltage, adjusts and applies measured piece 400
Operating current.Control unit 402 is when the electric current of measured piece 400 and/or electric voltage exception, single by driving
Unit 404 and high-current switch module 403 turn off measured piece 400, and control warning circuit and send sound and/or light report
Alert signal.
As shown in Figure 4, in order to prevent measured piece 400 overheated damaged, and obtain the real-time temperature of measured piece 400
Degree, the test system of the present embodiment further comprises the chiller 410 being arranged under measured piece 400 and phase therewith
Temperature sensor 411 even.Control unit 402 receives the temperature signal that temperature sensor 411 sends further,
According to the temperature of measured piece 400, sending running parameter to chiller 410, controlling chiller 410 is quilt
Survey part 400 to lower the temperature.
As shown in Figure 4, in order to see the current current value of measured piece 400, voltage more intuitively in the present embodiment
Value and temperature, be provided with display unit 412, for show the current current value of measured piece 400, magnitude of voltage and
Temperature.It addition, the data such as current current value, magnitude of voltage and temperature of measured piece 400 can also be sent to
Position machine 406 shows.
In the present embodiment, control unit 402 can use DSP to realize, and high-current switch module 403 can use
IGBT module realizes, and driver element 404 can be that the driving module that IGBT module is general realizes.Display unit
412 can be with LED) display screen or LCD display realize.Chiller 410 can use conventional cooling to fill
Put, can be specifically water cooling plant can also be air cooling equipment, such as: fan.Therefore, control unit 402
The running parameter sent to chiller 410, can be wind speed or the water flow velocity of water cooling plant of fan.Tool
The control mode of body is identical with prior art, repeats no more here.
Measured piece in the present embodiment is DBC and the copper soleplate completing aluminum wire bonding, in actual application, for
Be easy to test, can on DBC, reserve instrument connection, during test, by lead-in wire insert reserved instrument connection by
Measured piece is connected with high-current switch module 403.
Hereinafter the work process that this system is concrete is illustrated.
Host computer 406 controls software and sends the dutycycle of pulse PWM, frequency, power supply electricity to control unit 402
After the parameters such as stream I, send to control unit 402 and start order.Control unit 402 just produce corresponding frequencies with
The PWM waveform of dutycycle is input to driver element 404.Driver element 404 drives high-current switch module 403
Break-make, simultaneously control unit 402 to power subsystem 401 send instruction produce amplitude and specific electric current.Electric current
Flow through chip and DBC base plate by the bonding aluminum steel on measured piece 400, by the way of actively heating, make weldering
Connect chip and DBC heating, mainly measure the thermo parameters method situation of bonding point, divided by bonding point temperature
The situation of cloth judges the quality of bonding technology.
Owing to there being the temperature must be in certain scope when chip normally works, it is impossible to too high, be filled by cooling
Put 410 and part 400 to be measured is carried out radiating and cooling, with the closed loop control that control unit 402 forms temperature.
When carrying out actual test, by searching data base, it is judged that whether measured piece 400 has aluminum wire bonding to lack
Fall into.Data in data base are to add up great many of experiments test result in advance, it is thus achieved that thermo parameters method
Abnormal conditions and aluminum wire bonding defective workmanship and quantifying defects value corresponding relation.
Finally, it should be noted that the method for testing of the power semiconductor modular packaging technology of present invention offer,
It is exactly in power semiconductor modular encapsulation process, after chip bonding process completes, performs what the present invention provided
The testing procedure of chip bonding process, and after aluminum wire bonding technique completes, perform the aluminum steel that the present invention provides
The testing procedure of bonding technology.
Equally, the test system of the power semiconductor modular packaging technology that the present invention provides, just carried by the present invention
The test system of the chip bonding process of confession and the test system composition of aluminum wire bonding technique.Concrete, permissible
Set up process test system by two independent chip bonding process test systems and aluminum steel to realize, it is also possible to by
The test system sharing thermal infrared imager, host computer and data storage device realizes, and its operation principle is with aforementioned
Identical, explanation is not repeated herein.
So, in actual production process, use above-mentioned test system, determine certain by above-mentioned testing procedure
Chip bonding process and/or the aluminum wire bonding technique of individual product are defective, it is possible to eliminate this product in time,
Reduce defective product and perform the waste that subsequent technique causes.
The foregoing is only presently preferred embodiments of the present invention, be not intended to limit the protection model of the present invention
Enclose.All any modification, equivalent substitution and improvement etc. made within the spirit and principles in the present invention, all wrap
Containing within the scope of the present invention.
Claims (24)
1. the method for testing of a power semiconductor modular chip bonding process, it is characterised in that: at power
The chip bonding process of semiconductor module complete after perform following steps:
A, chip bonding process is completed after measured piece be placed on electric heating device, make the two closely paste
Merge fixing；
B, simulation actual condition apply different pulse voltage/electric currents to electric heating device；And/or apply to follow
Ring test voltage/current；
C, employing thermal infrared imager carry out thermo parameters method test to measured piece；
Whether D, thermo parameters method situation according to measured piece have exception, determine whether chip bonding process has
Defect.
2. method of testing as claimed in claim 1, it is characterised in that: described step D is: judge tested
Whether the temperature field of part has the point higher than mean temperature predetermined number of degrees with respect, determines the chip position weldering that this point is corresponding
Connect technique and have cavity blemish.
3. method of testing as claimed in claim 2, it is characterised in that: described predetermined number of degrees with respect is that 1-25 is Celsius
Degree.
4. method of testing as claimed in claim 1, it is characterised in that: in advance experimental results is carried out
Statistics, sets up thermo parameters method abnormal conditions and chip bonding process defect and quantifying defects value corresponding relation number
According to storehouse；
Described step D is: search the thermo parameters method situation of described measured piece in the database, if
Find, it is determined that have the chip bonding process defect of its correspondence, and provide the quantifying defects value of correspondence.
5. the method for testing as described in any one of claim 1-4, it is characterised in that: the method is real further
Time the monitoring electric current of electric heating device and voltage, according to current flow and voltage, adjust and electric heating device executed
Pulse voltage/the electric current added and/or loop test voltage/current.
6. method of testing as claimed in claim 5, it is characterised in that: the method uses cooling dress further
Put and measured piece is carried out radiating and cooling, and monitor the temperature of measured piece in real time, according to current temperature value, adjust
The running parameter of whole chiller.
7. realize a test system for the method for testing of chip bonding process described in claim 1, its feature
Be: include power subsystem, control unit, high-current switch module and driver element thereof, electric heating device,
Thermal infrared imager and host computer；
Described control unit is respectively connected with power subsystem, described driver element and host computer, this power subsystem
Also being connected with high-current switch module, this driver element is also connected with high-current switch module, described big electric current
Switch module is also connected with electric heating device；Described host computer is also connected with thermal infrared imager；
Measured piece after chip bonding process completes is placed on electric heating device, and the two fits tightly fixing；
The test parameter of the different operating modes that described control unit sends according to host computer, by controlling power subsystem
And driver element, controlling described high-current switch module is that electric heating device applies different pulse voltage/electricity
Stream；And/or apply loop test voltage/current；
Described host computer produces the test parameter of different operating mode and is sent to control unit, and receives thermal infrared imager
The temperature data of the measured piece sent, it is thus achieved that the thermo parameters method characteristic of measured piece, according to the temperature of measured piece
Whether field distribution situation has exception, determines that chip bonding process is the most defective.
Test system the most as claimed in claim 7, it is characterised in that: this system also includes and host computer phase
Data storage device even；
Described data storage device, prestore thermo parameters method abnormal conditions and chip bonding process defect and
Quantifying defects value corresponding relation data base；
Described host computer searches the thermo parameters method situation of described measured piece in the database, if searched
Arrive, it is determined that have the chip bonding process defect of its correspondence, and provide the quantifying defects value of correspondence.
Test system the most as claimed in claim 7 or 8, it is characterised in that: this system farther include with
Electric heating device be connected current sensor and voltage sensor；
Electric current and the voltage of electric heating device are sent to control by described current sensor and voltage sensor in real time
Unit processed；
Described control unit according to current flow and voltage, adjusts the pulse applying electric heating device further
Voltage.
Test system the most as claimed in claim 9, it is characterised in that: this system farther includes to arrange
Chiller under measured piece and the temperature sensor being attached thereto；
Control unit receives the temperature signal that temperature sensor sends further, according to the temperature of measured piece, to
Chiller sends running parameter, and controlling chiller is measured piece cooling.
11. test system as claimed in claim 10, it is characterised in that: described control unit connects report
Alert circuit, control unit, when the electric current of electric heating device and/or electric voltage exception, is turned off by driver element
Electric heating device, and control warning circuit and send sound and/or visual alarm.
The method of testing of 12. 1 kinds of power semiconductor modular aluminum wire bonding techniques, it is characterised in that: at power
The aluminum wire bonding technique of semiconductor module complete after perform following steps:
A, simulation actual condition aluminum wire bonding technique is completed after measured piece apply different running voltage/
Electric current；And/or apply loop test voltage/current；
B, employing thermal infrared imager click on trip temperature field distribution test to the aluminum wire bonding of measured piece；
Whether c, thermo parameters method according to the aluminum wire bonding point of measured piece have exception, determine aluminum wire bonding work
Skill is the most defective.
13. method of testings as claimed in claim 12, it is characterised in that: described step c is: judge quilt
Survey in the aluminum wire bonding point temperature field of part and whether have the point higher than mean temperature predetermined number of degrees with respect, determine that this point is corresponding
The bonding technology of aluminum wire bonding point have crack defect.
14. method of testings as claimed in claim 13, it is characterised in that: described predetermined temperature is 1-25
Degree Celsius.
15. method of testings as claimed in claim 14, it is characterised in that: in advance experimental results is entered
Row statistics, sets up thermo parameters method abnormal conditions and aluminum wire bonding defective workmanship and the defect level of aluminum wire bonding point
Change value corresponding relation data base；
Described step c is: search the temperature field minute of the aluminum wire bonding point of described measured piece in the database
Cloth situation, if found, it is determined that has the aluminum wire bonding defective workmanship of its correspondence, and provides quantifying defects
Value.
16. method of testings as described in any one of claim 12-15, it is characterised in that: the method enters one
The electric current of step monitoring measured piece in real time and voltage, according to current flow and voltage, adjust measured piece applying
Operating current.
17. method of testings as claimed in claim 16, it is characterised in that: the method uses cooling further
Device carries out radiating and cooling to measured piece, and monitors the temperature of measured piece in real time, according to current temperature value,
Adjust the running parameter of chiller.
18. 1 kinds of test systems realizing the method for testing of aluminum wire bonding technique described in claim 12, it is special
Levy and be: include power subsystem, control unit, high-current switch module and driver element, infrared thermal imagery
Instrument and host computer；
Described control unit is respectively connected with power subsystem, described driver element and host computer, this power subsystem
Also being connected with high-current switch module, this driver element is also connected with high-current switch module, described big electric current
Measured piece after switch module is completed with bonding technology by lead-in wire is connected；Described host computer also with infrared thermal imagery
Instrument is connected；
The test parameter of the different operating modes that described control unit sends according to host computer, by controlling power subsystem
And driver element, control described high-current switch module and measured piece is applied different running voltage/electric currents；
And/or apply loop test voltage/current；
Described host computer produces the test parameter of different operating mode and is sent to control unit, and receives thermal infrared imager
The temperature data of the aluminum wire bonding point of the measured piece sent, it is thus achieved that the temperature field minute of the aluminum wire bonding point of measured piece
Whether cloth characteristic, have exception according to the thermo parameters method situation of the aluminum wire bonding point of measured piece, determine aluminum steel key
Close technique the most defective.
19. test system as claimed in claim 18, it is characterised in that: this system also includes and host computer
The data storage device being connected；
Described data storage device, prestore thermo parameters method abnormal conditions and aluminum wire bonding defective workmanship and
Quantifying defects value corresponding relation data base；
Described host computer searches the thermo parameters method of the aluminum wire bonding point of described measured piece in the database
Situation, if found, it is determined that has the aluminum wire bonding defective workmanship of its correspondence, and provides quantifying defects value.
The 20. test systems as described in claim 18 or 19, it is characterised in that: this system farther includes
The current sensor being connected with measured piece and voltage sensor；
Electric current and the voltage of measured piece are sent to control list by described current sensor and voltage sensor in real time
Unit；
Described control unit according to current flow and voltage, adjusts the work electricity applying measured piece further
Pressure/electric current and/or loop test voltage/current.
21. test system as claimed in claim 20, it is characterised in that: this system farther includes to arrange
Chiller under measured piece and the temperature sensor being attached thereto；
Control unit receives the temperature signal that temperature sensor sends further, according to the temperature of measured piece, to
Chiller sends running parameter, and controlling chiller is measured piece cooling.
22. test system as claimed in claim 21, it is characterised in that: described control unit connects report
Alert circuit, control unit, when the electric current of measured piece and/or electric voltage exception, turns off tested by driver element
Part, and control warning circuit and send sound and/or visual alarm.
The method of testing of 23. 1 kinds of power semiconductor modular packaging technologies, it is characterised in that: weld at chip
Technique performs the testing procedure of the chip bonding process described in claim 1 after completing；In aluminum wire bonding technique
The testing procedure of execution aluminum wire bonding technique described in claim 12 after completing.
The test system of 24. 1 kinds of power semiconductor modular packaging technologies, it is characterised in that: include that right is wanted
Ask the test system described in 7 and the test system described in claim 18.
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| DE102014103180A1 (en) | 2014-03-10 | 2015-09-10 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Method for determining a bond connection in a component arrangement and testing device |
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| WO2018006309A1 (en) * | 2016-07-07 | 2018-01-11 | 张升泽 | Electrical current information sending method and system for electronic chip |
| CN107328821A (en) * | 2017-08-12 | 2017-11-07 | 深圳市埃塔测控技术有限公司 | A kind of method and apparatus that metal welding seam welding quality is tested with big DC current |
| CN111062920B (en) * | 2019-12-13 | 2023-06-20 | 北京百度网讯科技有限公司 | Method and device for generating semiconductor detection report |
| CN111965215A (en) * | 2020-08-13 | 2020-11-20 | 长江存储科技有限责任公司 | Packaged chip defect detection device and method thereof |
| CN112461369B (en) * | 2020-11-09 | 2023-04-18 | 泓准达科技(上海)有限公司 | Self-adjusting method and device for detecting electrical parameters of sample, medium and electronic equipment |
| CN113281008A (en) * | 2021-03-31 | 2021-08-20 | 昂纳信息技术（深圳）有限公司 | Chip welding state detection method for optical device |
| CN114632710B (en) * | 2022-02-16 | 2023-01-13 | 深圳米飞泰克科技股份有限公司 | Chip defective product screening method and device, terminal and server |
| CN115064455B (en) * | 2022-07-07 | 2023-01-03 | 西安晶捷电子技术有限公司 | Gold wire bonding process method |
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