CN104820344A

CN104820344A - Precision positioning platform Yaw value measurement method

Info

Publication number: CN104820344A
Application number: CN201510149387.1A
Authority: CN
Inventors: 李香滨; 方林
Original assignee: HEFEI ADVANTOOLS SEMICONDUCTOR CO Ltd
Current assignee: HEFEI ADVANTOOLS SEMICONDUCTOR CO Ltd
Priority date: 2015-03-31
Filing date: 2015-03-31
Publication date: 2015-08-05

Abstract

The invention discloses a precision positioning platform Yaw value measurement method. The method comprises installing a vacuum sucker on a precision positioning platform, adsorbing a high precision scaling board by the vacuum sucker, wherein the scaling board is provided with multiple lines and multiple rows of regularly arranged Marks, installing two fixed CCD image acquisition systems on a marble crossbeam, measuring Yaw values of a positioning platform X axle and Y axle at different positions by an image matching technology and drawing a curve. The method is suitable for fields of a direct writing lithography technology or other technologies utilizing a precision positioning platform. Compared with the conventional laser interferometer-based measurement method, the method has a low cost and can be operated easily. The precision positioning platform Yaw value measurement method has a high measurement precision and error of 0.1arc sec and can effectively assess dynamic performances of the precision positioning platform.

Description

A kind of measuring method of precisely locating platform Yaw value

Technical field

The invention belongs to precise Positioning Control field, relate to a kind of measuring method of precisely locating platform Yaw value, the present invention is applicable to plate-making photoetching technique, PCB direct-write photoetching technical field or is applied to the other technologies field of precisely locating platform.

Background technology

As shown in Figure 1, the Yaw value of precisely locating platform weighs an important indicator of locating platform dynamic perfromance, it depends primarily on several factor: the arranging effect etc. of the measure of precision of guide rail itself, the effect of guide rails assembling debugging, grating scale and guide rail, Yaw value at the major effect in PCB direct-write photoetching field is: affect the precision that ectonexine is aimed at, and affect the distortion of exposure figure.

Traditional precisely locating platform Yaw value measures the Angle Measurement Module mainly utilizing laser interferometer, along the direction that axle runs, measures the angle swinging that each position is brought because of yaw value.But adopt laser interferometer expensive, and assembly and adjustment process is complicated, method provided by the invention is both simple efficient, and it is accurate again to measure.

Summary of the invention

In view of the above-mentioned shortcoming of prior art, technical matters solved by the invention is: provide a kind of and be simple and easy to measuring method that is low with, cost and precisely locating platform Yaw value efficiently,

For achieving the above object, implementation of the present invention is: be placed into by high-precision calibrating plate customized on the vacuum cup of the locating platform system needing measurement, open vacuum suction, top adopts two high definition ccd image acquisition systems, when platform movement is to diverse location, Real-time Collection two mark, utilize the yaw value of images match method computing platform when diverse location.

Described image capturing system refers to be integrated in the high definition CCD on PCB direct-write lithography machine or other laser printing apparatus and Nonlinear magnify light path, and its general action is the aligning for direct-write photoetching equipment.

The field range of described image capturing system CCD is 12mm*12mm.

Described images match method refers to make the Mark in CCD visual field move to the method at the center of CCD visual field by the template of Mark and the algorithm of image procossing.

Figure deformation after the high precision photo-etching machine exposal of described making scaling board and convergent-divergent all very little, the distance <2um between general any two points.

The material of described scaling board is preferably glass base, and its thermal expansivity is 3.25PPM, and temperature is less on measuring the impact produced.

The object that described Yaw value is measured obtains the pivot angle size of platform when diverse location, and assess its impact brought complete machine graphical quality, and the rectification for figure provides reliable data.

Advantage of the present invention is:

The present invention than traditional laser interferometer measurement and cost of compensation low, easy to operate; Utilize images match method to measure, measuring accuracy is high, and error is about 700nm, can the error brought to machine system of Efficient Evaluation locating platform Yaw value.

Accompanying drawing illustrates:

Fig. 1 is precisely locating platform dynamic perfromance schematic diagram.

Fig. 2 is that scaling board Mark arranges schematic diagram.

Fig. 3 is that precisely locating platform yaw measures structural representation--normal axomometric drawing.

Fig. 4 is that precisely locating platform yaw measures structural representation--front view.

Fig. 5 is the schematic diagram that two CCD measures X-axis yaw.

Fig. 6 is the schematic diagram that two CCD measures Y-axis yaw.

Fig. 7 is X-axis Yaw measurement result schematic diagram.

Fig. 8 is Y-axis Yaw measurement result schematic diagram

It is as follows that attached number in the figure represents meaning:

1-marble lathe bed, 2-locating platform Y-axis, 3-vacuum cup, 4 – scaling boards, the left CCD system of 5-, be designated as the right CCD system of CCD1,6-, is designated as CCD2,7-marble crossbeam, 8 – locating platform X-axis.

In Fig. 2, a=10mm.

Embodiment

As shown in Figure 1, the dynamic perfromance of the every root axle of precisely locating platform comprises: Pitch (pitching), Roll (upset), Yaw (beat), Straightness (linearity) and Flatness (flatness).

Embodiment: as shown in figures 3 to 6.

A measuring method for precisely locating platform Yaw value, specific implementation is as follows:

Step1: as shown in Figure 3, is placed on scaling board 4 on vacuum cup 3, and the inferior horn that keeps left is located, and the Mark in its direction is anyhow as far as possible parallel with Y-axis with the X-axis of locating platform, and open vacuum suction and fix, vacuum cup is fixed in precisely locating platform X-axis 8.

Step2: as shown in Figure 2, scaling board has regularly arranged Mark, and X-direction spacing is a, and Y-direction spacing is b, when installing CCD1 and CCD2 system, need to ensure between two CCD at the space D x of X-direction to be the integral multiple of a.

Step3: the Yaw value first measuring X-axis, as shown in Figure 5, drive locating platform, a Mark1 on scaling board is made to move to CCD1 field of view center, record the coordinate (x1 of now locating platform, y1), because CCD1 and CCD2 is the integral multiple of a at the distance Dx of X-direction, and the visual field of CCD1 and CCD2 has 12mm*12mm big, so now on scaling board another Mark2 can enter into the field of view center of CCD2, record the now image coordinate of Mark2 in CCD2, and the image coordinate calculated now and theoretical center (CCD2 field of view center) distance Dy1 in the Y direction, therefore can obtain:

θ_{1} = \arctan \frac{Dy 1}{Dx}

Now obtained P1 place, position the angle θ 1 that obtains.

Step4: as shown in Figure 5, the integral multiple of mobile X-axis distance a or a, to position P2, repeats above step 3, and obtains Dy2, therefore can obtain:

θ_{2} = \arctan \frac{Dy 2}{Dx}

Now obtained P2 place, position the angle θ 2 that obtains.

Step5: continue mobile X-axis, repeats step 3 and 4, records angle θ 3 ~ θ n at P3-Pn place, position respectively.

Step6: according to the θ 1 ~ θ n recorded above, when calculating Y=y1 position, the Yaw value that different X-axis positions is corresponding is calculated as follows:

Yaw _x-P1=0, Yaw _x-P2=θ 2-θ 1, Yaw _x-P3=θ 3-θ 1 ... Yaw _x-Pn=θ n-θ 1, unit conversion becomes rad (arc sec).

Step7: the integral multiple of mobile Y-axis distance b or b, when measuring Y=y2, the Yaw value that different X-axis position is corresponding.

Step8: repeat Step7, measures Y=y3, y4 ... the Yaw value that different X-axis positions during yn are corresponding.

Step2 ~ Step8 measures the Yaw value method of X-axis, as shown in Figure 7, can draw out the curve map of X-axis Yaw under diverse location, as shown in Figure 7 according to the angle of measurement.

Step9: same to Step2 ~ Step8, in measuring process, Y-axis displacement need be the integral multiple of scaling board Mark line space b, in like manner can obtain the Yaw value that different Y-axis position is corresponding:

Yaw _Y-P1＝0,Yaw _Y-P2＝θ2-θ1,Yaw _Y-P3＝θ3-θ1…Yaw _Y-Pn＝θn-θ1

Step10: with Step7 and Step8, change X-axis position, measures X=x2, x3 ... the Yaw value that during xn, different Y-axis position is corresponding, can draw the curve map of Y-axis Yaw under diverse location, as shown in Figure 8 according to the angle of measurement.

Claims

1. a measuring method for precisely locating platform Yaw value, is characterized in that comprising following steps:

1) on surveyed precisely locating platform, install vacuum cup, be placed on by scaling board on vacuum cup, a lot of Mark of regular arrangement on scaling board, X-direction spacing is a, and Y-direction spacing is b.

2) on precisely locating platform, install two ccd image acquisition systems, the distance between two CCD is known;

3) drive locating platform by images match method, by scaling board, wherein a Mark is between two parties to the center of CCD1, and record the coordinate (x1, y1) of platform, the another one Mark with a line can be captured by CCD2, records the image coordinate of second Mark in CCD2;

4) X-axis of mobile precisely locating platform, allows platform movement distance a, repeats step 3);

5) under Y-axis coordinate Y=y1, step 4) is repeated;

6) integral multiple of mobile Y-axis distance b or b, repeats step 3), step 4), step 5);

Step 3) to step 6) is measure the Yaw value of X-axis;

7) get back to coordinate (x1, y1), repeat step 3);

8) Y-axis of mobile precisely locating platform, allows platform movement distance b, repeats step 3);

9) under X-axis coordinate X=x1, step 8) is repeated;

10) integral multiple of mobile X-axis distance a or a, repeats step 7), step 8), step 9);

Step 7) to step 10) is measure the Yaw value of Y-axis;

11) according to the image coordinate of CCD2 record, the Yaw value of X-axis and Y-axis is calculated.

2. the measuring method of precisely locating platform Yaw value according to claim 1, it is characterized in that: step 1) described in scaling board be substrate of glass, by etching gained after the exposure of high-accuracy exposure machine, the figure formed between the multiple mark of the Distance geometry between mark and the mark on it and error between theoretical value be all less than 2um.

3. the measuring method of precisely locating platform Yaw value according to claim 1, is characterized in that: when doing the measurement of Yaw value, and need use two CCD system in combination to measure, one of them CCD captures the center of Mark, and another one CCD only reads image coordinate.

4. the measuring method of precisely locating platform Yaw value according to claim 1, is characterized in that: the change can measuring the Yaw of X-axis when Y-axis diverse location, equally also can measure the change of Y-axis Yaw when X-axis diverse location.

5. the measuring method of precisely locating platform Yaw value according to claim 1, it is characterized in that: the platform can measuring single axis stage, X & Y right-angled intersection platform or gantry structure, the present invention is for X & Y right-angled intersection platform.