CN87209491U - Dynamic quality selecter for semiconductor rectifier - Google Patents

Abstract

The utility model discloses a dynamic quality selector for semiconductor rectifying devices which comprises a preheating device for tested pieces, an operating condition establishing part for standard conditions, an administrative system for an average current parameter extraction miniature machine and a matched machine sorting mechanism. The utility model designs a device which realizes multistage testing analysis by using environment temperature Ta and the dynamic quality average current as testing basis, and the device is matched with a first stage rechecking device. The utility model can ensure the set yield and is very beneficial to control quality in production plants and using plants.

Description

Dynamic quality selecter for semiconductor rectifier

The utility model belongs to semiconductor rectifier device quality sorting instrument, particularly is applicable to the specialized equipment in a large amount of device screening deciding grade and level processes.

The method and the instrument that the semiconductor rectifier device quality are divided selected class now both at home and abroad all according to the defined static parameter of IEC standard, carry out under some project stress condition of reinforcement.Its result, the device that is divided into the different quality grade only be a certain or several individual index on difference to some extent.Be in the rectifying device under the actual working state, its some index parameter weakens mutually, and some parameter is to strengthen mutually again.For example thermal effect can make forward voltage drop diminish under rectification state, and is favourable to rectifier; But thermal effect can make reverse average current increase again, and is harmful to rectifying device.Therefore, carry out quality grading by classic method and certainly will cause " test passes " and " go up machine qualified " inconsistent disadvantage, this is a higher basic reason of machine crash rate on the ubiquity rectifying device just also.

For solving the contradiction of " test passes " and " machine of going up lost efficacy ", the inventor has proposed according to " dynamically reverse average current

Mass analysis method, and designed " semiconductor rectifier device kinetic analyzer " (number of patent application 85107867).This instrument adopts new quality to assert that standard can solve the contradiction of " test passes " and " machine of going up lost efficacy " effectively.

The purpose of this utility model is under " dynamically reverse average current " theoretical direction, design the specialized equipment that a kind of dynamic mass divides selected class, with in factory or use factory to realize quality grading in enormous quantities in to the components and parts screening technology, to improve the last machine qualification rate of semiconductor rectifier device.

Design consideration of the present utility model and basic design are as follows:

According to patent of invention " semiconductor rectifier device kinetic analyzer and mass analysis method thereof " (application number: the dynamically reverse average current of the rectifying device that is proposed 85107867)

And have following relational expression under the environment temperature:

=Aae ^BaTa+ nC ... formula 1

Wherein (Aa, Ba C) are constant to parameter.Under a certain definite operating mode, one maximum of determining must be arranged to certain device of determining

Value, surpass it then device promptly can lose efficacy.For guaranteeing the reliability of device work, should be this maximum

Be multiplied by a safety coefficient and obtain the maximum oppositely average current that allows dynamically, be designated as

Device set for same specification all should meet this

Condition at this moment can be this

Value is considered as a standard, i.e. classification constant when quality is divided selected class.Can obtain its substitution formula 1 following:

Ta=1/ (Ba) Ln

Formula 2

This parameter Ta=Tam is the maximum permisible service temperature of this device.If under the detection actual condition (be environment temperature be set at IP＜under dynamically oppositely average current IP＜

Then think measured device can have under the Ta temperature higher on the machine reliability.That is to say that this device allows to use below the Ta temperature.If when sorting, the working temperature condition is divided into some grades, as: Ta1, Ta2 ... Tan so just can be according to actual measurement Contrast sub-elect the different grade of rectifying device and come.Can annotate upward usage flag according to environment temperature for the rectifying device that sorts out, as: 2CZ-53---75 ℃; Be beneficial to use producer as required appropriateness select, not only guaranteed machine qualification rate but also unlikely waste index.Concrete method of work is that the product to a certain lot number carries out the quality sampling analysis on kinetic analyzer earlier, by predetermined quality grade Ta1, Ta2 ... Tan measures corresponding

, then with Ta1, Ta2 ... Tan is as the working temperature condition of sorting units at different levels, with As the canonical parameter that detects contrast, thereby to this lot number product selecting deciding grade and level, this promptly is to use environment temperature Tam to be leading indicator overall quality method for separating.

According to above design, further specify basic structure characteristics of the present utility model in conjunction with the accompanying drawings:

Accompanying drawing 1 is the structural representation of dynamic mass sorting unit.

Wherein A is a first order sorting unit, and B is a second level sorting unit, and C is the public microcomputer management systems of sorting units at different levels.A1 is the primary heater of measured device, and A2 is that testing conditions is set the operating mode part, and A3 is that dynamic parameter is extracted circuit, and A4 is a mechanical sorting mechanism, and A5 is that specification product are deposited the storehouse, and A6 is that low grade products is deposited the storehouse, and A7 is the waste product storehouse.

Two key parameters are arranged in each grade sorting unit, the one, standard ambient temperature Tam, the one, the corresponding reverse dynamic current of the highest permission , Tam is a temperature of setting primary heater and operating mode,

Value is to send among the microcomputer RAM as the canonical parameter that detects contrast.

The effect of primary heater A1 is to make detected element enter the environment temperature that promptly reaches before the test position under the real working condition, thus the shortening test duration.Under the management of microcomputer management system, measured device at first enters primary heater, makes to reach test condition temperature T a1, reaches internal and external temperature and just enters the test position after in a basic balance, provides the dynamic test condition in the test position by simulated condition, passes through again It is one dynamic that parameter extraction circuit A3(is actually

Bridge diagram can be referring to the Fig. 4 in patent of invention 85107867 Figure of description) extract instant dynamically reverse average current

Value.Send into microcomputer by sampling interface C1 and carry out data processing, and and nominal parameters Contrast is handled the back and by the microcomputer Output Interface Control mechanical sorting A4 of mechanism device is sent into suitable position.The standard compliant certified products storehouse A5 that sends into, occur to puncture wait send into that A7 remaining parameter in waste product storehouse transfinites send into low-grade goods storehouse A6.Certified products promptly illustrate the minimum Ta1 of being of its operating ambient temperature by first order sorting.If can not upgrade after the second level is tested again, then this device can be stamped the environment serviceability temperature mark of Ta1.Its basic course of work was identical with the first order when certified products continued to enter second level sorting, and what standard temperature that different is was taked is higher temperature T a2 and corresponding parameters

Above working routine is realized by the supporting mechanical sorting mechanism of software commander under the microcomputer unified management.The software logic block diagram of single-stage sorting is with reference to figure 2.

In concrete device, operating mode is set up part A 2 and often is provided with a plurality of stations, once to test a plurality of devices, thereby not only improved separation velocity but also can satisfy each device the sufficiently long examination time that powers up had been arranged, set up the concrete setting of part about operating mode, comprise the structure of test position (chamber) and supporting electric voltage frequency is given all can add explanation no longer separately in addition with reference to the relevant design in the patent of invention 85207867.

So just obtain an overall quality chain by Tam classification under the highest environment for use temperature through the segmentation multipass sort, the components and parts that all divide selections all can pass through are then thought the quality product of overall quality.Carry out the branch selected class by above method and apparatus, owing to be to carry out according to the actual of the highest environment for use temperature T am, the height that makes quality and device reliability organic connections are together.Especially the tested number of times that quality is high more is many more, thereby product has higher confidence level after sorting.But the problem that exists is, segmentation is many, and separation velocity is slow, and the root scale of sorting unit is also bigger, invests higher.

For this reason, the utility model provides the quick sorting schemes of the dynamic sorting unit of quality, and it can remedy above deficiency, and is fundamentally consistent with above-mentioned method for separating again.Its basic point of departure is: with a kind of rectifying device of model, the product of especially same lot number because its structure is identical with technological process, makes the characterisitic parameter of certified products be close, in dynamic diode equation:

＝Aae ^BaTa＋

Coefficient Aa, constant

All be approximately constant respectively.The quality of quality is only by influence

Sensitivity Index Ba distinguish.This specific character exists

In-Ta the coordinate system, show as the appearance of Fig. 3.Be that curve is similar to coincidence at low-temperature space, disperse relatively rapidly in the high-temperature region.

On kinetic analyzer, can obtain easily Aa to certain model rectifying device,

Value.If under a certain environment temperature (Ta), record rectifying device 1., 2., 3. dynamically

Value is respectively

, then at known Aa,

Can obtain humidity index Ba1 separately under the representative value condition easily, Ba2, Ba3, so the dynamic equation of three measured devices is:

1＝Aae ^BaTa＋

2＝Aae ^BaTa＋

3＝Aae ^BaTa＋

Because the maximum dynamic current that allows Have simple linear relationship (seeing the straight line L among the figure) with high ambient temperature: =-1KTam+b then be easy to three dynamic equation simultaneous after obtain the highest permission environment temperature of three tested original papers: Tam1, Tam2, Tam3.If select Tam2 as ideal parameters, think that promptly the ideal of IP-Ta family of curves is dispersed temperature, be standard then with corresponding at this moment IPm2, then can once sub-elect high and low frequency modulator spare.According to above analysis, sorting unit of the present utility model can adopt a sorting of one-level success, the parameter A a that it is required,

, K, b etc. all can be by measuring (detailed in patent of invention 85207867) on the kinetic analyzer.Sorting unit can simplify greatly like this, and equipment investment also can significantly reduce, and separation velocity also can be accelerated greatly.Institute's its theoretical calculate of weak point and the certain error of physical presence, confidence level just is lower than the multistage classification and sorting certainly.But better in process conditions control, the occasion that homogeneity of product is higher, especially being not for a kind of desirable sorting schemes when the finished product repetition measurement, not having much differences on its concrete device, only is on the parameter in RAM district and Control Software corresponding modification to be arranged.

Fig. 4 is the synoptic diagram of mechanical sorting mechanism, wherein mainly is divided into three parts.Be last part in the wherein empty frame 1, empty frame 2 is a part of detecting, is mechanical arm in the empty frame 3.

Last part process is like this work, is dragged to carry by stepper motor 6 and leads chain 19 motions, advances to have a polarity determining device 4 in that supporting plate 5 is attached, inserts the device of leading on the chain and detects through polarity determining device 4 whether anti-inserted or disconnected utmost point phenomenon is arranged.Suitable device is installed is entered part of detecting by leading the chain transmission.Wherein weight 17 plays tensioning and leads chain and delay to lead defeated, top feeler 18 and cooperate microswitches 20 to send defeated condition prompting to lead chain for the operative employee.

Part of detecting comprises calibration cell 7, wherein fills the thermostatic medium of preheating device, lead chain therein crankle sufficient preheating is arranged to prolong preheating time after making device serve the test board position.It is constant that its temperature keeps, and establishes the well heater and the constant temperature control circuit that add by other and realize.Part of detecting is provided with a plurality of test boards position mouth, to realize a plurality of fast measuring.

Mechanical arm is actually the two-dimensional motion control that is realized adversary's formula dop 8 by stepper motor 9,10.Wherein 21,22 is shackle line.When tested element 11 is preheating to default environment temperature, utilize mechanical arm to take off automatically, send into monitor station position 12, carry out

Parameter Extraction, above action all have realization under the microcomputer unified management.Measured

After parameter is sent into MICROCOMPUTER PROCESSING, according to set

Comparative result, respectively measured device is sent to suitable deposit position by driving part mouth 13, wherein 14 is the certified products storehouse, 15 is the low-grade goods storehouse, 16 is puncture in the testing process, electrode fracture, parameter

Depart from the waste product storehouse that those devices that available model uses are deposited.

The action of mechanical sorting mechanism is controlled by implementing control interface C2 by microcomputer, the measured device that the device in the certified products storehouse is then chosen for the next stage branch, and what can finish the sorting task smoothly so repeatedly.

Above sorting unit is assemblied on factory's detection line, can realize the multiclass classification to device automatically, and guarantee use under the environment temperature that is indicated on the device have higher on the machine qualification rate.Also can be applicable on complete system plant's element screening line, can improve the failure rate of complete machine.Be a semiconductor rectifier device factory or an effective quality control device that uses factory in fact.

Claims (10)

1, a kind of semiconductor rectifier device dynamic mass sorting unit is characterized in that this device comprises primary heater (A1) the standard condition setting section of setting according to high ambient temperature Tam (A2), dynamic parameter

Extract circuit (A3), microcomputer management system (C) and mechanical sorting match mechanism (A4).

2,, it is characterized in that the temperature value of setting in primary heater and the standard condition depends on dynamic mass classification constant according to the said sorting unit of claim 1

, the number that primary heater and standard are provided with is according to the classification constant The class of dividing.

3, according to claim 1 or 2 said sorting units, it is characterized in that the design temperature in primary heater and the standard condition is TaM2, during application with TaM2 to using

For standard realizes the scalping of rectifying device finished product is screened.

4,, it is characterized in that comprising in the operating mode setting apparatus constant temperature holding device, frequency, voltage given device and fictitious load according to the said sorting unit of claim 1.

5, according to the said sorting unit of claim 1, it is characterized in that

Comprise a typical case in the parameter extraction circuit

Bridge diagram.

6, according to the said sorting unit of claim 1, it is characterized in that being provided with in the microcomputer management system data acquisition interface (C1) and one and implement control interface (C2), data are relatively judged and to the programmed control of mechanism action realizing by software.

7,, it is characterized in that mechanical sorting mechanism comprises part part 1, part of detecting 2 and mechanical arm 3 according to the said sorting unit of claim 1.

8, according to the said sorting unit of claim 7, it is characterized in that part part 1 by conveyer chain 19, supporting plate 5, polarity determining device 4, stepper motor 6 is formed.Detected element is sent into the test section behind polarity test.

9,, it is characterized in that the transmission that part of detecting comprises that permanent groove 7 is immersed in the pre-thermal medium leads chain and testboard bay 12 according to the said sorting unit of claim 7.

10, according to the said sorting unit of claim 7, it is characterized in that mechanical arm is the planar clamping device 8 that moves of bidimensional, by stepper motor 9,10, accurately its device loading and unloading that put in place of control, and the device after will measuring is delivered among the assigned address of staging libraries.

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