Summary of the invention
Based on this, it is necessary to provide a kind of resistance trimming method for thermistor.
A kind of resistance trimming method of thermistor, comprising:
Obtain the corresponding resistance increment rate range of each preset pattern in a variety of preset patterns;The preset pattern is used
In being formed in the piece resistance to resistance trimming, increase the resistance value that the piece to resistance trimming hinders;
The actual resistance that measurement is hindered to the piece of resistance trimming, and calculate increment rate required for reaching target resistance value;
Judge resistance increment rate range at the required increment rate, and obtains corresponding preset pattern;
The preset pattern that will acquire is applied to be trimmed to the piece resistance of resistance trimming.
Resistance trimming successively is carried out to multiple resistances in one of the embodiments: being applied in the preset pattern that will acquire
After the step of currently being trimmed to the piece resistance of resistance trimming, the actual resistance that next piece to resistance trimming hinders is measured.
Resistance trimming successively is carried out to multiple resistances in one of the embodiments: being applied in the preset pattern that will acquire
While currently being trimmed to the piece resistance of resistance trimming, the actual resistance that next piece to resistance trimming hinders is measured.
In one of the embodiments, to not meeting expected thermistor after trimming according to the preset pattern determined again
It is trimmed.
The step of acquisition resistance increment rate range includes: in one of the embodiments,
To every kind of preset pattern, it is applied to and trims multiple and different piece resistances, obtains multiple and different piece resistances and applying
Preset pattern trims the resistance increment rate of front and back;
The corresponding resistance increment rate range of every kind of preset pattern is determined according to multiple resistance increment rates obtained.
All resistance increment rate ranges are made not overlap and mutually connect by screening in one of the embodiments,.
In one of the embodiments, further include: be stored in preset pattern and corresponding resistance increment rate range correspondence
In database, and database is imported in laser resistance adjuster.
The multiple preset pattern includes the dot of different number, identical or different size in one of the embodiments,
Figure.
It is applied to hinder the step trimmed to the piece of resistance trimming in the preset pattern that will acquire in one of the embodiments,
In rapid, for meeting multiple resistance increment rate ranges of condition, one of them is selected to be trimmed.
It is applied to hinder the step trimmed to the piece of resistance trimming in the preset pattern that will acquire in one of the embodiments,
In rapid, for meeting multiple resistance increment rate ranges of condition, selection makes the smallest figure of resistance precision error after resistance trimming
It is trimmed.
The above method, the actual resistance of measure sheet resistance are carried out before laser trimming, are avoided due to laser generation
The case where heat causes thermosensitive resistance to change, and probe only needs single measurement, is guaranteeing accurate measurement temperature-sensitive electricity
While resistance value, resistance value measurement is also simplified.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.
Following embodiment provides a kind of resistance trimming method of thermistor, in the production process of thermistor to resistance value
The thermistor for not meeting target is trimmed, and keeps its resistance value eligible, improves yields.Temperature-sensitive in the present embodiment
Resistance refers in particular to square resistance, before encapsulation is completed, etches specific figure to resistance material and achievees the purpose that trim.
Resistance trimming method in the present embodiment is mainly executed by laser resistance adjuster.Laser resistance adjuster generally includes following portion
Point: optical system mainly includes laser, the scanning galvanometer and CCD online monitoring system for controlling optical path;Substrate transfer system
System mainly controls piece, running fix, bottom sheet etc. operation;Resistance value trace detection system, including probe card, precision type bridge and
Matrixing network etc..
Fig. 1 is the resistance trimming method flow diagram of the thermistor of an embodiment.This approach includes the following steps S110~S140.
Step S110: the corresponding resistance increment rate range of each preset pattern in a variety of preset patterns is obtained.It is described
Preset pattern is used to form in the piece resistance to resistance trimming, increases the resistance value that the piece to resistance trimming hinders.Preset pattern for example can be with
Be get ready, hilted broadsword, double-pole, L-type notch etc..A kind of preset pattern is applied when being trimmed in piece resistance, and resistance increment rate can be
Fluctuation in a certain range.It can be previously obtained the fluctuation range of the corresponding resistance increment rate of every kind of preset pattern, i.e. resistance increases
Rate range.The method of the present embodiment does not require the specific figure of thermistor, and piece resistance can be bar shaped, snakelike etc. tool
There is the shape of fixed boundary.
Step S120: the actual resistance that measurement is hindered to the piece of resistance trimming, and calculate and increase required for reaching target resistance value
Rate.The two poles of the earth that probe card on laser resistance adjuster can be hindered with piece contact, and measurement obtains the actual resistance R of piece resistance0.Assuming that target hinders
Value is R1, then reaching increment rate required for target resistance value is (R1-R0)/R0。
Step S130: judge resistance increment rate range at the required increment rate, and obtain corresponding pre-
If figure.
Step S140: the preset pattern that will acquire is applied to be trimmed to the piece resistance of resistance trimming.
The above method, the actual resistance of measure sheet resistance are carried out before laser trimming, are avoided due to laser generation
The case where heat causes thermosensitive resistance to change, and probe only needs single measurement, is guaranteeing accurate measurement temperature-sensitive electricity
While resistance value, resistance value measurement is simplified.
It generally, is be arranged in array multiple resistances of batch in the manufacturing process of thermistor, therefore resistance trimming
It should also be what batch carried out.When batch carries out resistance trimming, it may comprise steps of:
Obtain the quantity of the piece resistance in a thermistor;
By thermistor substrate carry out upper piece operation;
When upper piece substrate needs resistance trimming, executes above-mentioned steps S120~S140 and each piece resistance for needing resistance trimming is carried out
Trim processing.
After the completion of trimming, by upper piece substrate bottom sheet.
In one embodiment, what multiple pieces for needing resistance trimming hindered, which trim process, can be each resistance and successively successively executes
Step S120~S140.That is: it is applied to the step currently trimmed to the thermistor of resistance trimming in the preset pattern that will acquire
After rapid, the actual resistance of next thermistor to resistance trimming is measured.
In another embodiment, what multiple pieces for needing resistance trimming hindered, which trim process, is also possible to execute parallel.That is: it will obtain
While the preset pattern got is applied to currently be trimmed to the thermistor of resistance trimming, next temperature-sensitive to resistance trimming is measured
The actual resistance of resistance.For example, a piece of resistance starts to execute step under to current slice resistance while executing step S140
S120.The efficiency of processing can be improved in this way.
In other embodiments, it can also be that the actual resistance in advance by all piece resistances to be trimmed is measured, and
Resistance value increment rate required for calculating, and save.During subsequent resistance trimming, resistance value required for respective flap hinders is read
Increment rate, and transfer corresponding preset pattern and be applied to trim.
The method of above-described embodiment can also include: that determination is preset again to expected piece root resistance evidence is not met after trimming
Figure is trimmed.The process can be after the completion of all resistances all trim, then successively carry out resistance trimming to each resistance.
In above-mentioned steps S110, obtain resistance increment rate range the step of may include:
Step S111: to every kind of preset pattern, it is applied to and trims multiple and different piece resistances, obtain multiple and different pieces
It hinders in the resistance increment rate for trimming front and back using preset pattern.
Step S112: the corresponding resistance increment rate model of every kind of preset pattern is determined according to multiple resistance increment rates obtained
It encloses.
Piece hinders structure as shown in figure 3, piece resistance 100 includes conducting function area 110 and the electricity positioned at 110 two sides of conducting function area
Polar region 120 is respectively provided with a metal electrode 130 on two electrode districts 120.Wherein conducting function area 110 uses NTC material, gold
Gold electrode can be used by belonging to electrode 130.Two metal electrodes 130 are sheet, and part covers conducting function area 110, part and covers
Electrode district 120.And two metal electrodes 130 are spaced in conducting function area 110, exposed portion conducting function area 110.In resistance trimming
When machine trims the resistance value of piece resistance 100, it is to carry out hot spot etching in the part of the exposing, removes certain shapes and size
Region form the preset pattern 112 that trims.
In the present embodiment, tested with 0603 chip film NTC thermistor.0603 chip film NTC thermistor
Design size is 20 μm of 450 μ m, and in conjunction with the principle of laser resistor trimming, plan uses the diameter of different numbers for 10 μm of dot
As resistance trimming figure, different numbers of getting ready corresponds to different resistance trimming figures, each resistance trimming figure and its theoretic resistance
Change rate Δ R/R is corresponded.However resistance distribution actually to be adjusted is in a certain range, thus allow model in error
It encloses and interior converts range format for Δ R/R:
Get number ready |
1 |
2 |
3 |
4 |
ΔR/R |
0~1.5% |
1.5~3% |
3~5% |
5~7% |
The concrete processing procedure of step S111~S112 is illustrated below in conjunction with this.
Then resistance value first before measure sheet resistance resistance trimming successively carries out the resistance trimming experiment that difference gets number ready, is guaranteeing
The piece resistance after resistance trimming is measured under environment temperature unanimous circumstances.In order to avoid generating excessive heat, femtosecond can be used
Ultraviolet laser is got ready, the result is as follows:
Get number 1 ready:
Resistor body number |
Before resistance trimming (K Ω) |
After resistance trimming (K Ω) |
Δ(KΩ) |
ΔR/R |
#1 |
356 |
358.1 |
2.1 |
0.59% |
#2 |
351 |
354.8 |
3.8 |
1.08% |
#3 |
383 |
390 |
7 |
1.83% |
#4 |
384 |
387 |
3 |
0.78% |
Get number 2 ready:
Resistor body number |
Before resistance trimming (K Ω) |
After resistance trimming (K Ω) |
Δ(KΩ) |
ΔR/R |
#1 |
338 |
345 |
7 |
2.07% |
#2 |
306 |
313.7 |
7.7 |
2.52% |
#3 |
308 |
316.2 |
8.2 |
2.66% |
#4 |
365 |
374 |
9 |
2.47% |
Get number 3 ready:
Resistor body number |
Before resistance trimming (K Ω) |
After resistance trimming (K Ω) |
Δ(KΩ) |
ΔR/R |
#1 |
359 |
375 |
16 |
4.46% |
#2 |
350 |
368 |
18 |
5.14% |
#3 |
318 |
334.9 |
16.9 |
5.31% |
#4 |
337 |
353.4 |
16.4 |
4.87% |
Get number 4 ready:
As shown in figure 4, experimental result is dispersed in data model or more, experimental results error is less than 1.5%, in precision
It is required that the method for the present embodiment has quite high feasibility in less high range.
The mode of the above-mentioned resistance increment rate range for obtaining preset pattern is experimental method, in addition it is also possible to using emulation
Method.
The resistance increment rate range that above-mentioned each figure generates is not overlapped and is mutually connected.In this way, needing to adjust when having determined
After whole resistance increment rate, so that it may directly obtain the preset pattern of unique resistance trimming.It is appreciated that due to that can use
Different a variety of preset patterns, such as get ready, hilted broadsword, double-pole, L-type notch etc., it might have range between various preset patterns
Overlapping, if resistance increment rate simultaneously be in multiple ranges, any one can be chosen and trimmed.Further, may be used
Preferentially to be selected the preset pattern for being easier to implement to be trimmed according to the difficulty of implementation.It is also an option that making resistance essence after resistance trimming
The degree the smallest figure of error is trimmed, and makes to trim precision higher.
It is possible to further after the corresponding relationship for obtaining preset pattern and resistance increment rate range, by preset pattern and
Corresponding resistance increment rate range correspondence is stored in database profession.The database can import in laser resistance adjuster, adjusted
When resistance, laser resistance adjuster directly reads data from database, obtains preset pattern.
Set about verifying the reliability of resistance trimming figure below.The thermistor to be adjusted for one, the resistance trimming mesh of each resistance
Mark resistance value is 360K Ω, and experiment randomly selects on substrate 25 resistance in 5 × 5 ranges, measures theirs at identical conditions
Resistance value distribution such as following table (unit: K Ω):
349.3 |
347.9 |
339.5 |
337.5 |
334 |
347.5 |
346.5 |
345.5 |
339.3 |
344.9 |
347.5 |
348.1 |
347.1 |
335.8 |
337.2 |
342.7 |
341.4 |
337.7 |
343.8 |
336.5 |
342.2 |
342.2 |
339.3 |
333.2 |
335.6 |
The resistance change rate Δ R/R that band trims resistance Yu target resistance value is calculated separately according to step S120, and determination is each
The resistance trimming scheme of piece resistance, as a result such as following table (representing the different resistance trimming schemes for getting number ready in bracket):
Resistor body is trimmed according to selected resistance trimming scheme, experimental result distribution is as follows:
369 |
366 |
367 |
366 |
364 |
366 |
369 |
366 |
370 |
355 |
367 |
366 |
365 |
362 |
365 |
362 |
363 |
367 |
363 |
364 |
360 |
360 |
366 |
369 |
364 |
It can be seen that the resistance value after trimming is substantially distributed near target resistance value 360K Ω, thus conception proposed by the present invention
There is quite high feasibility within the scope of the prior art.
The method of above-described embodiment, resistance trimming process carry out before protective film formation.This method is in conventional laser resistance adjuster
On the basis of improved to obtain, in the complexity of no increase system and on the basis of maintain original resistance trimming efficiency, make
Its resistance trimming that can be used for thermistor.It solves traditional tracing type measurement and resistance trimming and is not applied for asking for thermistor
Topic.
Each technical characteristic of embodiment described above can be combined arbitrarily, for simplicity of description, not to above-mentioned reality
It applies all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited
In contradiction, all should be considered as described in this specification.
The embodiments described above only express several embodiments of the present invention, and the description thereof is more specific and detailed, but simultaneously
It cannot therefore be construed as limiting the scope of the patent.It should be pointed out that coming for those of ordinary skill in the art
It says, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to protection of the invention
Range.Therefore, the scope of protection of the patent of the invention shall be subject to the appended claims.