CN101349539B - Micro-force measuring method of hole perpendicularity - Google Patents

Abstract

The invention discloses a process for measuring the perpendicularity of a hole, which is carried out based on a principle that three points can determine a circle, and measures through using two fixed probes and a movable probe. The movable probe can move to the inner walls of all probe contact holes after the three probes enter into the hole, then coordinate values of the three probes are recorded, and the circle center coordinate of the hole on the cross section can be obtained according to the method that three points can determine a circle. And the heights of the probes in round holes can be regulated, and the circle center coordinates of the hole on different cross sections can be obtained through repeating the method, thereby obtaining the perpendicularity of the hole. The invention can rotate the probes when measures the circle center of the cross section, changes measuring angle, and obtains multiple testing results, and then takes the resultant value of testing results. The invention has high testing efficiency and simple and easy operation, and is suitable for detection in batch.

Description

Micro-force measuring method for verticality of hole

[ technical field ] A method for producing a semiconductor device

The invention relates to the field of measurement, in particular to a perpendicularity measuring method.

[ background of the invention ]

To calculate the verticality, the circle center positions (represented by coordinates) of the hole to be measured on different cross sections are measured, and then the verticality is calculated by using a verticality calculation formula. The existing verticality measurement generally adopts a CMM (coordinate measuring machine) machine, and the measurement method comprises the following steps: the workpiece is fixed, only one probe is provided, each stopping position of the probe can be recorded, the probe is adopted to carry out point-by-point scanning on 8 points equally distributed on the inner wall of the hole of each cross section (the probe stops after touching the inner wall to reach a certain force, and coordinates of the points are recorded), so that the center coordinates of the hole of each cross section are obtained, and the coaxiality is calculated according to the center coordinates.

The method has the defects that only a single probe carries out point-by-point measurement, and the efficiency is low; the coordinate value is recorded only after the single probe touches the inner wall and reaches a certain force, instantaneous feedback cannot be realized, the measurement precision is influenced, and the operation difficulty is high.

[ summary of the invention ]

The invention aims to solve the technical problem of providing a verticality measuring method with high measuring efficiency aiming at the defects of the prior art, and also provides a verticality measuring method with simple operation.

In order to solve the technical problems, the invention adopts the following technical scheme:

a micro-force measuring method for perpendicularity of a hole comprises the following steps:

three spherical probes are extended into a round hole of an object to be detected, wherein the three spherical probes comprise a fixed first probe, a fixed second probe and a movable third probe;

measuring a first circle center coordinate of a first cross section of the circular hole;

moving the three spherical probes along the axial direction of the round hole;

measuring a second circle center coordinate of a second cross section of the circular hole;

calculating the perpendicularity of the round hole according to the first circle center coordinate and the second circle center coordinate;

the method comprises the following steps of measuring the displacement of an object to be measured, calculating the center coordinates of the first cross section or the center coordinates of the second cross section according to the center coordinates of the three spherical probes and the displacement, and specifically comprises the following steps:

measuring and calculating a first relative circle center coordinate relative to a set coordinate system and a first cross section according to the steps, and measuring the translation amount in the X direction and the translation amount in the Y direction by a displacement sensor;

and in the same cross section, the rotating mechanism drives the probe to rotate by an angle theta from the original point, and then the seat of the cross section relative to the circle center is measured according to the method. Marking the diameter, measuring the translation amount in the X direction and the translation amount in the Y direction simultaneously, projecting the coordinates into a set coordinate system, and finally projecting the coordinate value of a second relative circle center after superimposing the translation amounts;

in the same cross section, the rotating mechanism drives the probe to rotate reversely by an angle theta from the original point to measure the coordinate and the diameter of the relative circle center, and simultaneously measures the translation X in the X direction₃And the amount of translation Y in the Y direction₃Projecting the coordinate into a set coordinate system, superposing the translation amount and finally projecting a coordinate value of a third phase relative to the center of a circle;

calculating a first circle center coordinate of a circle formed by a first relative circle center, a second relative circle center and a third relative circle center of the first cross section, wherein the first circle center coordinate is a coordinate value of the circle center of the cross section;

and according to the steps, calculating a second circle center coordinate of the second cross section.

Further, measuring a first circle center coordinate of the first cross section of the circular hole or a second circle center coordinate of the second cross section of the circular hole comprises the following steps:

recording initial coordinates of the spherical centers of the first probe and the second probe;

moving the third probe until the three spherical probes contact the inner wall of the hole, and obtaining the spherical center coordinate of the third probe;

calculating a first circle center coordinate or a second circle center coordinate of a circle circumscribed with the three spherical probes;

and calculating the perpendicularity of the round hole according to the first circle center coordinate and the second circle center coordinate.

The invention has the following beneficial effects:

1. according to the invention, 2 probes are fixed and 1 probe moves, and the coordinates of three points can be determined by moving one probe, so that the measurement efficiency is improved;

2. the invention automatically feeds back the electric signal to start reading when the three probes simultaneously contact the inner wall, does not depend on the force of the probes contacting the inner wall, and has simple operation;

3. the invention is adopted to measure the verticality, the object to be measured does not need to be fixed and can move, the stress of the probe is avoided, and the measurement precision is improved.

[ description of the drawings ]

FIG. 1 is a schematic diagram of the determination of a circumscribed circle by three probes of the present invention

The invention will be further described with reference to the accompanying drawings.

[ detailed description ] embodiments

The invention uses the principle that three points determine a circle, uses three probes to determine the coordinates of three points on the same cross section of the inner wall of the round hole, and calculates the circle center of the round hole on the cross section. And (3) moving the probe along the axial direction of the circular hole, calculating the circle center coordinates of different cross sections, and determining whether the perpendicularity of the hole wall meets the standard according to the dispersion degree of the circle center coordinates.

Firstly, a method for measuring the circle center coordinate of the aperture on a certain cross section is explained.

The probe is generally spherical, the radii and initial coordinates of the 3 probe circles are known, and the coordinates of the centers and the sizes of the radii of the circumscribed circles of the three circles can be solved.

As shown in FIG. 1, in a given coordinate system, let the first circle radius be R₁The center of the circle is (X)_A，Y_A) The second circle radius is R₂The center of the circle is (X)_B，Y_B) The third circle radius is R₃The center of the circle is (X)_c，Y_c) The radius of the circumscribed circle is R, and the coordinates are (X, Y), then:

(X-X_A)²+(Y-Y_A)²＝(R-R₁)²

(X-X_B)²+(Y-Y_B)²＝(R-R₂)²

(X-X_C)²+(Y-Y_C)²＝(R-R₃)²

in the actual measurement process, twoThe probes are fixed, the third probe moves towards a fixed direction, and the hole wall is pushed in the moving process, so that the three probes are all in contact with the hole wall. The position of the two probes is fixed, i.e. known (X)_A，Y_A)、R₁，(X_B，Y_B)、R₂. Three position parameters (X) of the third Probe_C，Y_C)、R₃In, R₃Is known, X is fixed moving in the Y direction_CIs fixed and Y_CAre variable. The start of the moving probe is determinable, then Y_CWhere C is the Y value of the moving probe at the start position and the movement value is the Y-direction movement distance of the third probe from the start position to when all three probes are in contact with the hole wall, which can be obtained by the position sensor. That is, in the above three equations, except X, Y and R, the rest are known, and thus, the following can be obtained from the above equation:

X＝B₃+SQR(B₃ ²-4A₃C₃)/(2A₃) Or X₀＝B₃-SQR(B₃ ²-4A₃C₃)/(2A₃)

Y＝A₁-B₁X₀

R＝A₂X+B₂

Wherein,

$A_1=\frac{(R_2-R_1)({X_A}^2+{Y_A}^2-{X_C}^2-{Y_C}^2+{R_3}^2-{R_1}^2-(R_3-R_1)({X_A}^2+{Y_A}^2-{X_B}^2-{Y_B}^2+{R_2}^2-{R_1}^2)}{2[(Y_B-Y_A)(R_3-R_1)-(Y_C-Y_A)(R_2-R_1)]}$

$B_1=\frac{(X_B-X_A)(R_3-R_1)-(X_C-X_A)(R_2-R_1)}{(Y_B-Y_A)(R_3-R_1)-(Y_C-Y_A)(R_2-R_1)}$

$A_2=\frac{(X_B-X_A)-(Y_B-Y_A)B_1}{R_2-R_1}$

$B_2=\frac{{X_A}^2+{Y_A}^2-{X_B}^2-{Y_B}^2+{R_2}^2-{R_1}^2+2(Y_B-Y_a)A_1}{2(R_2-R_1)}$

A₃＝1+B₁ ²-A₂ ²

B₃＝2(X_A+(A₁-Y_A)B₁+A₂(B₂-R₁))

C₃＝X_A ²+(A₁-Y_A)²-(B₂-R₁)²

in the same cross section, in order to obtain more accurate circle center coordinates, the probe is rotated to select three testing directions, three circle center coordinates can be calculated according to the method, then the principle that three points determine a circle is utilized again, the three circle centers determine a new circle center coordinate, and the new circle center coordinate is the circle center coordinate of the round hole to be measured on the cross section. The circle center coordinates of different cross sections required for calculating the verticality can be obtained by measuring on different cross sections.

In the measuring process, when the probe mechanism rotates to measure in different directions, the object to be measured can generate relative displacement relative to the initial position, so that the object to be measured is not at the same position when measuring the circle center coordinate every time, and if the circle center coordinate at the same position of the object to be measured is not used for calculation, the accuracy of calculating the circle center coordinate of a certain cross section can be influenced, and the accuracy of calculating the verticality can also be influenced. Therefore, the displacement of the object to be measured with respect to the initial position must be taken into consideration for the measurement. The displacement can be obtained by measuring the amount of X-direction translation and the amount of Y-direction translation.

The specific measurement process is as follows:

1. measuring the coordinate (X) of the center O of the first cross-section₃₃，Y₃₃)

(1) According to the method described above, the first center coordinate O of the first cross section can be measured and calculated relative to the set coordinate system₁(X₀₁，Y₀₁) Simultaneously measuring the translation X in the X direction by a displacement sensor₁And the amount of translation Y in the Y direction₁。

(2) In the same cross section, the rotating mechanism drives the probe to rotate by the angle theta from the original point, and then the relative circle center coordinate O of the cross section is measured according to the method₂(X₀₂，Y₀₂) Diameter of D₂And simultaneously measuring the translation X in the X direction₂And the amount of translation Y in the Y direction₂Projecting the coordinate to a set coordinate system, superposing the translation amount and finally projecting a second circle center O₂₂The coordinate values of (A) are:

X₀₂₂＝X₀₀₁+X₂-X₁

Y₀₂₂＝Y₀₀₁+Y₂-Y₁

wherein:

X₀₀₁＝D₁*zj₂-Sqr((D₁^2*zj₂^2)-(1+zj₂^2)*(D₁^2-zj₁)))/(1+zj₂^2)

Y₀₀₁＝D₁-X₀₀₁

zj₁＝X₀₂^2+Y₀₂^2

D₁＝zj₁*(1-2*Sin(θ/2)^2)/Y₀₂

zj₂＝X₀₂/Y₀₂

(3) in the same cross section, the rotating mechanism drives the probe to rotate reversely from the original point by an angle theta and measures a coordinate O relative to the circle center₃(X₀₃，Y₀₃) Diameter of D₃And simultaneously measuring the translation X in the X direction₃And the amount of translation Y in the Y direction₃Projecting the coordinate into a set coordinate system, superposing the translation amount and finally projecting a third circle center O₃₃The coordinate values of (A) are:

X₀₃₃＝X₀₀₂+X₃-X₁

Y₀₃₃＝Y₀₀₂+Y₃-Y₁

wherein:

X₀₀₂＝(D₂*zj₄+Sqr((D₂^2*zj₄^2)-(1+zj₄^2)*(D₂^2-zj₃)))/(1+zj₄^2)

Y₀₀₁＝D₂-X₀₀₂

zj₃＝X₀₃^2+Y₀₃^2

D₂＝zj₃*(1-2*Sin(θ/2)^2)/Y₀₃

zj₄＝X₀₃/Y₀₃

(4) calculating O₁(X₀₁，Y₀₁)，O₂₂(X₀₂₂，Y₀₂₂)，O₃₃(X₀₃₃，Y₀₃₃) Center coordinates (X) of circle formed by three points₃₃，Y₃₃) I.e. the coordinate value of the circle center O of the cross section is as follows:

X₃₃＝(X₀₃₃^2+Y₀₃₃^2-X₀₁^2-Y₀₁^2+2*bb*(Y₀₁-Y₀₃₃))/(2*(X₀₃₃-X₀₁)+aa*(Y₀₃₃-Y₀₁))

Y₃₃＝aa*X₃₃+bb

wherein:

aa＝(X₀₂₂-X₀₁)/(Y₀₁-Y₀₂₂)

bb＝(X₀₁^2+Y₀₁^2-X₀₂₂^2-Y₀₂₂^2)/(2*(Y₀₁-Y₀₂₂))

2. calculating the coordinate value (X) of the center O' of another cross section according to (1) - (4)₃₃₃，Y₃₃₃)

3. Calculating the verticality T

T＝Sqr((X₃₃₃-X₃₃)^2+(Y₃₃₃-Y₃₃)^2)

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (2)

1. A micro-force measuring method for perpendicularity of a hole comprises the following steps:

three spherical probes are extended into a round hole of an object to be detected, wherein the three spherical probes comprise a fixed first probe, a fixed second probe and a movable third probe;

measuring a first circle center coordinate of a first cross section of the circular hole;

moving the three spherical probes along the axial direction of the round hole;

measuring a second circle center coordinate of a second cross section of the circular hole;

calculating the perpendicularity of the round hole according to the first circle center coordinate and the second circle center coordinate;

the method is characterized by further comprising the step of measuring the displacement of the object to be measured, wherein the circle center coordinate of the first cross section or the circle center coordinate of the second cross section is calculated according to the sphere center coordinates of the three spherical probes and the displacement, and the method specifically comprises the following steps:

measuring and calculating a first relative circle center coordinate relative to a set coordinate system and a first cross section according to the steps, and measuring the translation amount in the X direction and the translation amount in the Y direction by a displacement sensor;

in the same cross section, the rotating mechanism drives the probe to rotate by an angle theta from the original point, then the coordinate and the diameter of the cross section relative to the circle center are measured according to the method, the translation amount in the X direction and the translation amount in the Y direction are measured simultaneously, the coordinate is projected into a set coordinate system, and the translation amounts are superposed to finally project a second coordinate value relative to the circle center;

in the same cross section, the rotating mechanism drives the probe to rotate reversely by an angle theta from the original point to measure the coordinate and the diameter of the relative circle center, and simultaneously measures the translation X in the X direction₃And the amount of translation Y in the Y direction₃Projecting the coordinate into a set coordinate system, superposing the translation amount and finally projecting a coordinate value of a third phase relative to the center of a circle;

calculating a first circle center coordinate of a circle formed by a first relative circle center, a second relative circle center and a third relative circle center of the first cross section, wherein the first circle center coordinate is a coordinate value of the circle center of the cross section;

and according to the steps, calculating a second circle center coordinate of the second cross section.

2. The method for measuring the verticality of a hole according to claim 1, wherein: measuring a first circle center coordinate of the first cross section of the circular hole or a second circle center coordinate of the second cross section of the circular hole comprises the following steps:

recording initial coordinates of the spherical centers of the first probe and the second probe;

moving the third probe until the three spherical probes contact the inner wall of the hole, and obtaining the spherical center coordinate of the third probe;

and calculating the first center coordinate or the second center coordinate of the circle circumscribed with the three spherical probes.

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