CN202770361U - Silicon wafer thickness measuring instrument - Google Patents

Abstract

The utility model provides a silicon wafer thickness measuring instrument to improve the accuracy of the thickness measurement of silicon wafers. The silicon wafer thickness measuring instrument of the utility model comprises a measuring platform and a support. A measuring meter for measuring the thickness of a silicon wafer is arranged on the support, the distance between the measuring meter and the measuring platform is adjustable, the measuring platform is provided with a boss for placing the silicon wafer to be measured, and the top surface of the boss has a recessed structure. Even when air exists between the silicon wafer and the top surface of the boss, the air can enter the recessed structure on the top surface of the boss only by applying a small force so as to ensure the zero-clearance contact between the silicon wafer and the top surface of the boss, and the numerical value measured by the measuring meter at this time is the true thickness of the silicon wafer, so the silicon wafer thickness measuring instrument can be used to ensure that the measurement result will not be larger than the true thickness of the silicon wafer. The above-mentioned principle is equally applicable to liquid, so the accuracy of the measurement result can also be ensured when liquid exists on the silicon wafer.

Description

A kind of silicon chip thickness gauge

Technical field

The utility model relates to the engineering machinery field of measuring technique, particularly relates to a kind of thicknessmeter for the silicon wafer thickness measurement.

Background technology

As everyone knows, the geomery of silicon chip has determined the geomery of solar battery sheet.Wherein, the thickness of silicon chip and uniformity coefficient thereof affect the manufacturing of follow-up cell piece and the encapsulation of assembly to a great extent, affect especially great on the fragment rate of later stage operation.Therefore, the thickness of silicon chip and homogeneity thereof are to weigh the important indicator of silicon chip quality.

In the prior art, the measurement of silicon wafer thickness is general adopts special silicon chip thickness gauge to finish.Existing silicon chip thickness gauge generally includes measuring table and meter, is connected with support on the measuring table, and meter is installed on the support, and the height of this meter is adjustable.

Generally, the measurement of silicon wafer thickness need to be chosen five points, is generally four angle points and the central point thereof of silicon chip.What meter adopted is a contact measurement, during measurement, at first by support meter is fixed, and then silicon chip thickness gauge is placed on the worktable of level, opens meter and carries out the zero setting calibration; Lift gently afterwards the probe of meter, silicon chip to be measured is placed between measuring table and the probe; Follow mobile silicon chip, with its central point be placed on probe under, and probe is pressed on this central point, the reading on this moment meter is the thickness of silicon chip central spot.After finishing the measurement of central point, probe is lifted gently, mobile silicon chip is finished the measurement of four corner point thickness of silicon chip according to the method described above.

There is following problem in above-mentioned existing silicon chip thickness gauge:

Because the thickness of silicon chip all about 0.18mm, is the precision that guarantees that silicon wafer thickness is measured generally, to realize seamless applyingly between silicon chip and the measuring table as far as possible, that is to say, basically there is not the gap between the bottom surface of silicon chip and the supporting surface of measuring table.But since between silicon chip and the measuring table for face contacts, air between the two can not be discharged fully so that contacting between the silicon chip of measurement point and the measuring table is incomplete, this just causes the measured value of silicon wafer thickness bigger than normal; In addition, sometimes also need measuring through prewashed silicon wafer thickness, and the silicon chip when measuring is stained with a lot of cleaning fluids, will have in this case liquid between silicon chip and the measuring table, and then cause the error of measurement result larger; These liquid to silicon chip pick and place and silicon chip moves and all brings very large difficulty, silicon chip is frangible in addition, measure or mobile process in, if undue force, the probability that is easy to cause fragment or increases fragment in the following process.

Can adopt following way to address the above problem:

In the center of measuring table protruding planchet is set, the area of this projection planchet is less than the area of silicon chip, directly silicon chip is placed on the described protruding planchet during measurement, air between the two will outwards overflow from both engagement edges, so that contact between the two is tightr, reduce the impact that silicon wafer thickness is measured.

But, adopting said method, the air between silicon chip and the protruding planchet can not effectively be discharged from, and also has air trapping greatly between both surface of contact, and then causes the result of thickness measure bigger than normal.Because the minimizing of the strong point must cause the micro-deformation of measuring silicon chip, has also greatly increased the possibility of silicon chip fragment when causing thickness measurements bigger than normal.

Therefore, how a kind of thicknessmeter that silicon wafer thickness is measured that is specifically designed to is set, the precision of measuring to improve silicon wafer thickness is the present technical issues that need to address of those skilled in the art.

The utility model content

The purpose of this utility model provides a kind of silicon chip thickness gauge, precision and the convenience measured to improve silicon wafer thickness.

For solving the problems of the technologies described above, the utility model provides a kind of silicon chip thickness gauge, comprise measuring table and support, described support is provided with for the meter of measuring silicon wafer thickness, distance between described meter and the described measuring table is adjustable, described measuring table is provided with for the boss of placing silicon slice under test, and the end face of described boss has sunk structure.

Because what the measurement of silicon wafer thickness was taked is the mode that reconnaissance is measured, for reducing the clearance between silicon chip and the boss end face, boss of the present utility model is provided with sunk structure at its end face, even have air between the end face of silicon chip and boss, as long as apply a less power, this air just can enter under the extruding of external force in the described sunk structure, and then discharge or be stored in the described sunk structure by described sunk structure, thereby guarantee that silicon chip contacts with zero stand-off between the boss end face, the numerical value that this moment, meter was measured is the actual thickness of silicon chip, guarantees that measurement result can be not bigger than normal.In addition, in the situation of silicon chip with liquid, described sunk structure can also be as the accommodation space of liquid, with fluid storage section or discharge within it, reducing the impact of liquid on measuring, and then reduces measuring error.

Preferably, described boss is cylindrical boss, and the external diameter of its end face is 20-40mm.

The end face external diameter of boss is arranged in the above-mentioned scope, can be effectively the air between silicon chip and the boss or liquid be discharged from its edge, again supporting silicon chip preferably.

Preferably, described sunk structure is a plurality of shrinkage pools, and each described shrinkage pool all is communicated with to form through hole with outside.

Preferably, the number of described through hole is 8-14, and each described through hole is uniform on described end face.

The setting of through hole number can provide for the discharge of air or liquid more passage, and each through hole uniform so that on the end face everywhere exhaust or drainability remain on same level, avoided the emission point of air or liquid too concentrated, so that exhaust or draining are quicker.

Preferably, also be provided with back up pad on the described measuring table, the supporting surface of described back up pad and the end face of described boss are in the same level face, in order to jointly support silicon slice under test.

With the boss isoplanar back up pad is set, described back up pad can with the common supporting silicon chip of boss, reducing the deflection of silicon chip, thereby reduce the impact of measuring the silicon chip following process; The setting of back up pad also so that silicon chip can be more stable when measuring, has been avoided the measuring error that produces because silicon chip is unstable.

Preferably, the edge of described boss and back up pad all has the buffering suface that is the certain slope setting.

Buffering suface can reduce the sharpness at the edge of boss and back up pad, thereby reduces both edge and the probability that collides with of silicon chip, avoids the silicon chip injury.

Preferably, the gradient of described buffering suface is 45 degree.

Preferably, described back up pad is the circular slab of external diameter between 70-90mm.

The edge smoother of circular slab is also just less to the damage of silicon chip; Simultaneously, in the certain situation of girth, circular area is maximum, adopts circular slab can increase it to the supporting surface of silicon chip, thereby increases the stability that silicon chip is placed; In addition, the tangential direction of each point is different on the arc edge of back up pad, and gas or air are difficult to stop in its edge, and this just is conducive to the discharge of gas and liquid more; Because the size of silicon chip generally concentrates in certain scope, the area of back up pad is limited in the above-mentioned scope, can make it effectively can not have influence on the discharge of air in the supporting silicon chip, thereby take into account the stability of support and the discharging of air.

Preferably, described back up pad is even number, and the described back up pad of even number is take the center line of described boss as the rotational symmetry setting.

Described back up pad is symmetrically distributed in the both sides of boss, and when silicon chip was placed on the boss, each orientation of silicon chip can both effectively be supported, and silicon chip is also just more stable; When four angle points to silicon chip carry out thickness measure, can from different orientation angle point to be measured be placed on the boss respectively, then adopt different back up pads that silicon chip is supported, can better meet the thickness measure demand of silicon chip angle point, also help picking and placeing and moving of silicon chip.

Preferably, described back up pad is annular or the shaped as frame that is sleeved on described boss outside and setting coaxial with it.

Back up pad is set to annular or shaped as frame, can simplify processing and the installation process of back up pad, reduces the quantity of back up pad; And the back up pad of this hollow structure can be taken into account the demand of silicon chip support and air venting better.

Description of drawings

Fig. 1 is the perspective view of silicon chip thickness gauge that the utility model provides in a kind of embodiment;

Fig. 2 provides the plan structure synoptic diagram of a kind of set-up mode of measuring table for the utility model;

Fig. 3 is when measuring the thickness of silicon chip angle point, and silicon chip is placed on the structural representation on the measuring table shown in Figure 2;

Fig. 4 is when measuring the thickness of silicon chip central point, and silicon chip is placed on the structural representation on the measuring table shown in Figure 2.

Embodiment

Core of the present utility model provides a kind of silicon chip thickness gauge, can improve the precision that silicon wafer thickness is measured, and improves the convenience that silicon wafer thickness is measured.

In order to make those skilled in the art person understand better the utility model scheme, the utility model is described in further detail below in conjunction with the drawings and specific embodiments.

Please refer to Fig. 1, Fig. 1 is the perspective view of silicon chip thickness gauge that the utility model provides in a kind of embodiment.

In a kind of embodiment, silicon chip thickness gauge of the present utility model comprises measuring table 1, support 2 and meter 3, meter 3 is used for measuring the thickness of silicon chip, meter 3 is arranged on the support 2, support 2 is used for supporting meter 3, support 2 can be set directly on the measuring table 1, also can be arranged on a side of measuring table 1, and the distance between meter 3 and the measuring table 1 is adjustable; Measuring table 1 is provided with boss 11, and boss 11 has for the end face 111 of placing silicon slice under test, and this end face 111 has the through hole 112 that can be connected with the outside; Meter 3 has the position of measurement 31, and the measurement range of measuring position 31 can cover the end face 111 of boss 11, so that this measurement position 31 can touch the silicon slice under test of placing on the boss 11, and then obtains the thickness of silicon chip by contact measurement.Generally speaking, the measurement position 31 of meter 3 is perpendicular with the end face 111 of boss 11, thereby the measurement that guarantees measurement position 31 is more accurate.

Because meter 3 is arranged on the support 2, adjust for realizing the distance between meter 3 and the measuring table 1, in the situation that support 2 is fixedly installed, meter 3 can be connected on the support 2 by the bolt spiral, then realize the shift in position of meter 3 by the twisting bolt; Under support 2 is arranged on situation on the measuring table 1, meter 3 can be fixedly installed on the support 2, and adopt adjustable for height movable connection method between support 2 and the measuring table 1, by the position realization meter 3 of change support 2 and the shift in position between the measuring table 1.Certainly, between meter 3 and the support 2, the mode that all can adopt bolt etc. to be flexibly connected between support 2 and the measuring table 1, change realizes the adjustment of distance between meter 3 and the measuring table 1 in the time of by two kinds of link positions.Obviously, realize that the mode that the distance between meter 3 and the measuring table 1 is adjusted is not limited only to the above-mentioned movable connection methods such as bolt of mentioning, and can also adopt other connected modes realizations such as clamping.

Shown in Figure 1 preferred embodiment in, meter 3 is digital display dial gauge, the measurement position 31 of meter 3 is a probe structure, this probe can stretch out or retracts with respect to the main body of digital display dial gauge.At this moment, between above-mentioned support 2 and the measuring table 1, all can adopt the mode that is fixedly connected with between meter 3 and the support 2, the flexible state that only needs to change probe just can be realized the measurement to silicon wafer thickness, and it is more convenient to operate.

When adopting silicon chip thickness gauge of the present utility model to measure, at first need meter 3 is carried out the zero setting calibration, so that the reading that shows during the end face 111 of the measurement position 31 of meter 3 contact boss 11 is zero, the part silicon chip that then will include tested point is placed on the end face 111, adjust afterwards the distance between meter 3 and the boss 11, so that the measurement position 31 of meter 3 be in boss 11 directly over, the then range difference between contract measurement position 31 and the end face 111 gradually, can come in contact with silicon chip until measure position 31, read measurement result after the stable reading of scale 3 to be measured, this reading is the thickness at tested point place on the silicon chip.Adopt above-mentioned setting, the end face of boss 11 has through hole 112, when having air between boss 11 and silicon chip, as long as silicon chip is applied a less pressing force, air just can discharge by through hole 112, and the gap between boss 11 and the silicon chip is eliminated basically; After the prerinse of silicon chip process, can be with liquid on the silicon chip, these liquid impact also can for the measurement of silicon wafer thickness, the through hole 112 of this moment can also be as freeing port, the liquid that carries on the silicon chip is discharged, and then avoid liquid on the impact that measurement causes, reduce measuring error.

On this basis, the area of the end face 111 of boss 11 can be less than the area of silicon chip, that is to say, adopt small size to contact between boss 11 and the silicon chip, the contact of this small size so that air between the two can outwards overflow from both engagement edges, thereby reduce clearance between the two, improve the precision of measuring; Meanwhile, the contact of small size is so that exist some idle spaces between boss and the silicon chip, and these idle spaces pick and place and mobilely provide a larger free operant leeway for silicon chip, so that the measurement of silicon wafer thickness can be carried out better faster.

Need to prove that the way that through hole 112 is set on the above-mentioned boss 11 only is a kind of embodiment of the present utility model, the purpose of its setting is to be convenient to the air between the end face 111 of silicon slice under test and boss 11 is discharged as much as possible.For achieving the above object, through hole 112 can be a plurality of tiny through holes, also can be the larger through hole that connects whole boss 11; In addition, can also groove be set at the end face 111 of boss 11, this groove can be used as aqua storage tank or air reservoir, and the air between end face 111 and the silicon slice under test or liquid are squeezed in the described groove.Obviously; the setting of above-mentioned groove also can realize and through hole 112 essentially identical functions; therefore; protection domain of the present utility model is not limited only at the end face 111 of boss 11 through hole 112 is set; get final product so long as have a sunk structure on the end face 111; then the air between silicon chip and the end face 111 or liquid just can enter in this sunk structure, also just can the measurement of silicon wafer thickness not exerted an influence.This sunk structure can be shrinkage pool or groove, and this shrinkage pool or groove can be connected to form with the outside through hole, also can be blind hole.

Can silicon chip thickness gauge mentioned above be further improved.

Please refer to Fig. 2 to Fig. 4, Fig. 2 provides the plan structure synoptic diagram of a kind of set-up mode of measuring table for the utility model; Fig. 3 is when measuring the thickness of silicon chip angle point, and silicon chip is placed on the structural representation on the measuring table shown in Figure 2; Fig. 4 is when measuring the thickness of silicon chip central point, and silicon chip is placed on the structural representation on the measuring table shown in Figure 2.

In preferred implementation shown in Figure 2, boss 11 can be arranged on the centre position of measuring table 1, to guarantee the smoothness of boss 11, the tightness degree between the end face 111 of raising silicon chip and boss 11.At this moment, the measurement position 31 of meter 3 can also be arranged on the center line of boss 11, guarantee to measure position 31 and be pressed on the central point of boss 11, because can be more steady when silicon chip is placed on the center of boss 11, the thickness of the silicon chip that then obtains at this point measurement be more near its actual value.

For satisfying the needs of exhaust or draining, the number of through hole 112 is generally 8-14, and each through hole 112 preferably can be evenly distributed on the end face 111 of boss 11, to guarantee the ability that all has draining or exhaust everywhere on the end face 111, in order to avoid concentrating too much on a place, liquid or air discharge, thereby can improve to a certain extent the speed of exhaust or draining, guarantee that gas or the liquid between boss 11 and the silicon chip is discharged smoothly.

In another preferred embodiment, silicon chip thickness gauge of the present utility model also is provided with back up pad 12, back up pad 12 is arranged on the measuring table 1, the end face 111 of the supporting surface of back up pad 12 and boss 11 is in the same plane, that is to say, the end face 111 of the supporting surface of back up pad 12 and boss 11 has consisted of the holding plane of silicon chip jointly, and both jointly finish the support of silicon chip is fixed, thereby can guarantee the stability of silicon chip when measuring.Certainly, the area of back up pad 12 is unsuitable excessive, otherwise may affect the Bas Discharged between back up pad 12 and the silicon slice under test; And the distance between back up pad 12 and the boss 11 can not be greater than the size of silicon slice under test, otherwise does not have supporting role.

Consider that silicon chip is frangible, on the basis of above-mentioned embodiment, the edge of boss 11 and back up pad 12 can be processed, edge at both arranges the buffering suface (not shown), namely its edge is carried out chamfered, this buffering suface has certain gradient, the impact that silicon chip is caused with the edge that relaxes both, avoid itself and silicon chip to collide with, also just can not be to the silicon chip injury.

Experiment shows, when the gradient of above-mentioned buffering suface is 45 when spending, the edge of boss 11 and back up pad 12 can drop to minimum to the damage of silicon chip, and the buffering suface of this gradient relatively is easy to processing.

Can expect that the shape of above-mentioned back up pad 12 can be set to circle.When back up pad 12 was circular slab, its edge was rounder and more smooth, also will be smaller to the damage of silicon chip; As everyone knows, in the certain situation of girth, circular area is maximum, adopts the setting of circular slab to provide larger supporting surface for silicon chip, so that silicon chip is more stable; In addition, the tangential direction of the circular arc each point of circular slab is all different, and this is conducive to gas and liquid discharges through its edge.

It will also be appreciated that boss 11 can be set to columniform boss.Boss 11 can arrange according to the size of silicon chip with the size of back up pad 12, for example, the external diameter of back up pad 12 can be arranged between the 70-90mm, and the external diameter of the end face 111 of boss 11 can be between 20-40mm, and the distance that both protrude measuring table 1 can be 1mm.A kind of more preferred embodiment in, the external diameter of back up pad 12 can be 80mm, the external diameter of the end face of boss 11 is 30mm, and the setting of this kind size can guarantee the formedness that silicon chip contacts with boss 11, back up pad 12, thereby takes into account the stability of silicon chip support and the requirement of discharged air.

In addition, the number of back up pad 12 can be a plurality of, and back up pad 12 also can adopt the setting of even number, then with the back up pad 12 of even number take the center line of boss 11 as the rotational symmetry setting.In embodiment shown in Figure 2, back up pad 12 can be set to 4, these 4 back up pads 12 are symmetrical arranged about the center line of boss 11.

As shown in Figure 3, when the angle point to silicon chip 4 carries out thickness measure, at first an angle point with silicon chip 4 is placed on the end face 111 of boss 11, then the main part with silicon chip 4 is placed on one of them back up pad 12, and need not manually to grip silicon chip, this has not only reduced the pollution and the damage that artificially silicon chip 4 are caused in the measuring process, can also improve the stability of silicon chip 4 in measuring process, and then improves the precision of measuring; In like manner, as shown in Figure 4, when the central point of silicon chip 4 is measured, the central point of silicon chip 4 need to be placed on the boss 11, and when the area of boss 11 during less than the area of silicon chip 4, support if lack effectively, silicon chip 4 is easy to produce distortion or displacement, and this causes puzzlement can for undoubtedly the thickness measure of silicon chip 4, also can reduce the levels of precision of silicon chip 4 thickness measures, and the setting of back up pad 12 can be controlled above-mentioned distortion and displacement, the assisted Extraction high measurement accuracy; Simultaneously, between each back up pad 12, also have the gap between back up pad 12 and the boss 11, can satisfy between silicon chip 4 and the back up pad 12, the air between silicon chip 4 and the boss 11 or the emissions requirements of liquid.

Obviously, back up pad 12 is not limited in the structure of above-mentioned circular slab, back up pad 12 can also be set to annular or shaped as frame, the structure of described annular or shaped as frame can be sleeved on the outside of boss 11, and setting coaxial with it that is to say, back up pad 12 is identical with the axis of boss 11.The back up pad 12 of this moment can arrange one, and the external diameter of this annular backup pad 12 can equal the length of side of silicon slice under test 4, perhaps is slightly larger than or less than the length of side of silicon chip 4; And the back up pad 12 of shaped as frame can be square or rectangle, and short length of side will be equal to or less than the length of side of silicon chip 4 in its outside, that is to say that back up pad 12 will have two limits can play to silicon chip 4 effect of support at least.

More than silicon chip thickness gauge provided by the utility model is described in detail.Used specific case herein principle of the present utility model and embodiment are set forth, the explanation of above embodiment just is used for helping to understand core concept of the present utility model.Should be understood that; for those skilled in the art; under the prerequisite that does not break away from the utility model principle, can also carry out some improvement and modification to the utility model, these improvement and modification also fall in the protection domain of the utility model claim.

Claims (10)

1. silicon chip thickness gauge, comprise measuring table and support, described support is provided with for the meter of measuring silicon wafer thickness, distance between described meter and the described measuring table is adjustable, described measuring table is provided with for the boss of placing silicon slice under test, it is characterized in that the end face of described boss has sunk structure.

2. silicon chip thickness gauge as claimed in claim 1 is characterized in that, described boss is cylindrical boss, and the external diameter of its end face is 20-40mm.

3. silicon chip thickness gauge as claimed in claim 1 is characterized in that, described sunk structure is a plurality of shrinkage pools, and each described shrinkage pool all is communicated with to form through hole with outside.

4. silicon chip thickness gauge as claimed in claim 3 is characterized in that, the number of described through hole is 8-14, and each described through hole is uniform on described end face.

5. such as each described silicon chip thickness gauge of claim 1 to 4, it is characterized in that also be provided with back up pad on the described measuring table, the supporting surface of described back up pad and the end face of described boss are in the same level face, in order to jointly support silicon slice under test.

6. silicon chip thickness gauge as claimed in claim 5 is characterized in that, the edge of described boss and back up pad all has the buffering suface that is the certain slope setting.

7. silicon chip thickness gauge as claimed in claim 6 is characterized in that, the gradient of described buffering suface is 45 degree.

8. silicon chip thickness gauge as claimed in claim 5 is characterized in that, described back up pad is the circular slab of external diameter between 70-90mm.

9. such as each described silicon chip thickness gauge of claim 6 to 8, it is characterized in that described back up pad is even number, the described back up pad of even number is take the center line of described boss as the rotational symmetry setting.

10. silicon chip thickness gauge as claimed in claim 5 is characterized in that, described back up pad is annular or the shaped as frame that is sleeved on described boss outside and setting coaxial with it.

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