CN103324036A - Device and method for detecting ratio and distortion of projection objective - Google Patents

Abstract

The invention provides a device and method for detecting the ratio and distortion of a projection objective. The device comprises the projection objective, a fixing unit and a bearing unit which are arranged in a frame unit, wherein the lower surface of the bearing unit is arranged on the surface of the bottom of the frame unit; the fixing unit is positioned between the projection objective and the frame unit; the outer end face of the fixing unit is fixedly connected with the inner wall of the frame unit; the inner end face of the fixing unit is fixedly connected with the side wall of the projection objective; the bottom of a transfer printing mask plate is positioned on the upper surface of the bearing unit; a chromium-plated surface of the transfer printing mask plate is close to the bottom of the projection objective; a distance is formed between the chromium-plated surface of the transfer printing mask plate and the bottom of the projection objective; the opening of the frame unit is fixedly connected with the bearing unit; the upper surface of the bearing unit is connected with the lower surface of a measurement mask plate; an illumination unit is positioned above the measurement mask plate; a chromium-plated surface of the measurement mask plate is close to the bottom of the illumination unit; a distance is formed between the bottom of the illumination unit and the chromium-plated surface of the measurement mask plate.

Description

The pick-up unit of a kind of projection objective magnification and distortion and method

Technical field

The invention belongs to projection optical system Performance Detection field, particularly the detection method of a kind of projection objective magnification and distortion.

Background technology

Development along with the projection lithography technology, the projection optical system performance of litho machine progressively improves, litho machine has been successfully applied to the integrated circuit manufacturing field of sub-micron and deep-submicron resolution at present, require projection objective to have higher resolution when making integrated circuit (IC) chip with the photoetching machine, to realize the manufacturing of highly integrated chip, the optical imaging system that also requires projection exposure to use has less magnification error and distortion simultaneously, when preparing to satisfy chip, and the interconnected conducting between the levels.In the process of the integrated survey of litho machine equipment complete machine school, need carry out performance test to each system that comprises projection objective and demarcate, projection objective magnification error and distortion are one of important performance indexes that needs test calibration.

Measurement for multiplying power and distortion, still use conventional methods mostly at present, namely place a masterplate that has the standard grid graph at object space, drive optical sensor with the motion platform that can do the two dimensional surface motion, position and distortion with the direct measurement pattern aerial image of mode that scans whole visual field, perhaps take the mode of exposing, the figure of masterplate grid after the imaging of acquired projections object lens obtains magnification error and the distortion of camera lens by the method for measuring the exposure figure deflection.

There is uncorrectable systematic error in the aforesaid technology: at first, there is error template graphics in itself, measured lens ratio and distortion have comprised the error of mask itself, measurement result can't be distinguished the error that there is the sum of errors projection objective in mask itself, in addition, adopt the mode of scanning field of view or measure the mode of exposure no matter be, because there is positioning error in measuring equipment itself, final reading has comprised the factor of measuring equipment, and measurement result can't identify this fractional error equally.And the existence of these problems also will directly have influence on the final performance of lithographic equipment.

Previous patent (publication number: also have CN101387833A) to relate to the method that projection objective magnification and distortion are determined in double exposure, but provide method moderate multiplying factor and distortion computation model to be applicable to that projection objective name multiplying power is about-1 situation in this patent, the present invention expands the computer capacity of the computation model of multiplying power and distortion computation model, be applicable to that not only nominal multiplying power is about-1 situation, but also be applicable to the situation of other multiplier value.

Summary of the invention

The device and method that the purpose of this invention is to provide a kind of projection objective magnification and distortion.This method can accurately be measured the absolute multiplying power of projection objective itself and distortion by the photoetching method of image exchange exposure.

A first aspect of the present invention, the pick-up unit of a kind of projection objective magnification and distortion is provided, described device comprises: frame unit, projection objective, fixed cell, hold blade unit, the board unit, lighting unit, measure mask plate and transfer mask plate, wherein: be placed with projection objective in the frame unit, fixed cell, hold blade unit, the lower surface that holds blade unit is placed on the surface of frame unit bottom, fixed cell is between projection objective and frame unit, fixedly connected with the inwall of frame unit in the outer face of fixed cell, the inner face of fixed cell is fixedlyed connected with the sidewall of projection objective; The bottom of transfer mask plate is positioned on the upper surface that holds blade unit; The chromium plating face of transfer mask plate has a distance near the bottom of projection objective between the chromium plating face of transfer mask plate and the bottom of projection objective; Opening part at frame unit is fixedlyed connected with the board unit, and board unit upper surface is connected with the lower surface of measuring mask plate; Lighting unit is positioned at measures the mask plate top, measures the chromium plating face of mask plate near the bottom of lighting unit, and has a distance between the chromium plating face of the bottom of lighting unit and measurement mask plate.

A second aspect of the present invention, the detection method of a kind of projection objective magnification and distortion is provided, it is applied in the pick-up unit of projection objective magnification and distortion, described device comprises frame unit, projection objective, fixed cell, holds blade unit, board unit, lighting unit, measurement mask plate and transfer mask plate, and described method comprises the following steps

Step S1: prepare one and measure mask plate, form a plurality of printing opacity marks at the chromium plating face of measuring mask plate, the printing opacity mark is lattice-shaped and is distributed in the projection objective field range to be measured, and records the nominal position of each printing opacity mark;

Step S2: get a mask plate that does not have figure as the transfer mask plate, apply positive photoresist at the chromium plating face of transfer mask plate, obtain to scribble the chromium plating face of positive photoresist;

Step S3: the chromium plating that will measure mask plate faces projection objective and is installed on the board unit; The chromium plating of the positive photoresist that the transfer mask plate is scribbled faces lighting unit and is installed in and holds on the blade unit; Regulate the height of projection objective and board unit, make that measuring mask plate and transfer mask plate is in separately with respect to the nominal position of projection objective, realizes the image conjugation;

Step S4: according to setting exposure dose, open lighting unit and begin illumination, the graphic projection of measuring the printing opacity mark of mask plate is arrived picture side, make the positive photoresist sensitization of transfer mask plate, note the image position of measuring figure on the mask plate; The transfer mask plate stayed through development, etching, at the chromium plating face of transfer mask plate measure the picture that mask plate becomes through projection objective;

Step S5: the chromium plating face that will measure mask plate applies positive photoresist, and chromium plating is faced lighting unit is installed in and holds on the blade unit, and the chromium plating of transfer mask plate is installed on the board blade unit towards projection objective;

Step S6: according to the exposure dose of setting, open lighting unit, the graphic projection of transfer mask plate is arrived picture side, make the photoresist sensitization of measuring mask plate also through development, etching, write down the picture that the transfer mask plate becomes through projection objective at chromium plating face subscript, the chromium coating of measuring mask plate this moment has comprised the initial position message of printing opacity mark and the positional information that twice imaging transmitted through projection objective;

Step S7: the standard deviation of measuring the positional information of the initial position message of each nominal position correspondence of printing opacity mark and the printing opacity mark that twice imaging transmitted through projection objective by the alignment machine, bring in projection objective magnification error and the distortion model and find the solution, obtain magnification error and distortion.

Beneficial effect of the present invention: the present invention compares with the projection objective magnification of prior art and the detection method of distortion, the present invention has set up new multiplying power and the computation model of distortion, makes this method can be used for measuring projection objective magnification and the distortion of any multiplying power.The present invention prepares a measurement mask plate with lattice-shaped printing opacity mark, provide the mask plate that applies positive photoresist on the chromium plating face and do not have figure as the transfer mask plate simultaneously, utilize relevant devices such as the method for image exchange exposure and gluing development, etching, alignment measurement, adopt the present invention that multiplying power and the distortion of projection objective are measured, effectively the systematic error brought of traditional measurement means such as exclusion standard grid template.The projection objective that the present invention can be used in the nominal multiplying power of any measurement detects.

Description of drawings

Fig. 1 realization the invention provides the synoptic diagram of a system platform of detection method;

Fig. 2 measures a synoptic diagram with mask plate

Fig. 3 will measure printing opacity mark on the mask plate and see through projection objective and be imaged onto light path synoptic diagram on the transfer mask plate;

Fig. 4 is the synoptic diagram that is coated in the shaping photoresist sensitization on the transfer mask plate;

Fig. 5 is the development synoptic diagram of exposure back transfer mask plate;

Fig. 6 is for measuring the mark synoptic diagram of the corresponding transfer mask plate of mask plate;

Fig. 7 is the light path synoptic diagram that will measure after the exchange of mask plate and transfer mask Board position;

Fig. 8 is again the development synoptic diagram that mask plate is measured in the exposure back;

Fig. 9 is again that exposure back transfer mask plate is corresponding to the mark synoptic diagram of measuring mask plate;

Figure 10 is for realizing detection method process flow diagram of the present invention.

Embodiment

Be described in further detail below with reference to the detection method of a preferred embodiment to projection objective magnification of the present invention and distortion.

Fig. 1 is for realizing an experiment porch of detection method provided by the invention, as shown in the figure, comprised frame unit 1, projection objective 2, fixed cell 3, hold blade unit 4, board unit 5, lighting unit 6, measure mask plate 7 and transfer mask plate 8, be placed with projection objective 2 in the frame unit 1, fixed cell 3, hold blade unit 4, the lower surface that holds blade unit 4 is placed on the surface of frame unit 1 bottom, fixed cell 3 is between projection objective 2 and frame unit 1, fixedly connected with the inwall of frame unit 1 in the outer face of fixed cell 3, the inner face of fixed cell 3 is fixedlyed connected with the sidewall of projection objective 2; The bottom of transfer mask plate 8 is positioned on the upper surface that holds blade unit 4; The chromium plating face of transfer mask plate 8 near the bottom of projection objective 2 it, have a distance between the bottom of the chromium plating face of transfer mask plate 8 and projection objective 2; Opening part at frame unit 1 is fixedlyed connected with board unit 5, and board unit 5 upper surfaces are connected with the lower surface of measuring mask plate 7; Lighting unit 6 is positioned at measures mask plate 7 tops, measures the chromium plating face of mask plate 7 near the bottom of lighting unit 6, and has a distance between the chromium plating face of the bottom of lighting unit 6 and measurement mask plate 7.

Wherein, described transfer mask plate 8 is the mask plates that do not have figure, applies positive photoresist at the chromium plating face of transfer mask plate 8.

Wherein, the chromium plating of the positive photoresist that scribbles of described transfer mask plate 8 faces lighting unit 6 and is installed in and holds on the blade unit 4.

Wherein, regulate the height of described projection objective 2 and board unit 4, make to measure mask plate 7 and transfer mask plate 8 and be in separately with respect to the nominal position of projection objective 2, realize the image conjugation.

Wherein, at a plurality of printing opacity marks of chromium plating face formation of described measurement mask plate 7, the printing opacity mark is lattice-shaped and is distributed in projection objective 2 field ranges to be measured, and records the nominal position of each printing opacity mark.

Wherein, the graphic projection of measuring the printing opacity mark of mask plate 7 is arrived picture side, make the positive photoresist sensitization of transfer mask plate 8, note the image position of measuring figure on the mask plate 7; Transfer mask plate 8 stayed through developments, etching, at the chromium plating face of transfer mask plate 8 measure mask plate 7 through the picture of 2 one-tenth of projection objectives.

Wherein, the chromium plating face of measuring mask plate 7 applies positive photoresist, and chromium plating faces lighting unit 6 and be installed in and hold on the blade unit 5, and the chromium plating of transfer mask plate 8 is installed on the board blade unit 5 towards projection objective 2.

Wherein, according to the exposure dose of setting, open described lighting unit 6, the graphic projection of transfer mask plate 8 is arrived picture side, make the photoresist sensitization of measuring mask plate 7 also through development, etching, write down transfer mask plate 8 through the picture of 2 one-tenth of projection objectives at chromium plating face subscript, the chromium coating of measuring mask plate 7 this moment has comprised the initial position message of printing opacity mark and the positional information that 2 twice imaging are transmitted through projection objective.

Wherein, measure the standard deviation of the positional information of the initial position message of each nominal position correspondence of printing opacity mark and the printing opacity mark that 2 twice imaging are transmitted through projection objective by the alignment machine, bring in the magnification error of projection objective 2 and the distortion model and find the solution, obtain magnification error and distortion.

The detection method of projection objective magnification of the present invention and distortion is applied in the pick-up unit of projection objective magnification and distortion, and the flow process of detection method of the present invention below is elaborated according to flow process as shown in figure 10.As Fig. 2, shown in Figure 3:

Step S1: prepare one and measure mask plate 7, form a plurality of printing opacity marks at the chromium plating face of measuring mask plate 7, the printing opacity mark is lattice-shaped and is distributed in projection objective 2 field ranges to be measured, and records the nominal position of each printing opacity mark; Projection objective 2 by fixed cell 3, is installed on the frame unit 1, and the chromium plating face 701 that will include the measurement mask plate 7 of grid-like arrangement printing opacity mark 702 is installed on the board unit 5.

Step S2: get a mask plate that does not have figure, as transfer mask plate 8, at the chromium plating face 801 coating positive photoresists 802 of transfer mask plate 8, obtain to scribble the chromium plating face of positive photoresist; Chromium plating face 801 is installed to lighting unit and holds on the blade unit 4.

Step S3: the chromium plating that will measure mask plate 7 faces projection objective 2 and is installed on the board unit 5; The chromium plating of the positive photoresist that transfer mask plate 8 is scribbled faces lighting unit 6 and is installed in and holds on the blade unit 4; By projection objective 2, fixed cell 3 and board unit 5, adjust projection objective to be measured 2 and measure the height of mask plate 7, make that measuring mask plate 7 and transfer mask plate 8 is in separately on the nominal position with respect to projection objective 2, realizes the image conjugation.

Step S4: as shown in Figure 3, according to setting exposure dose, open lighting unit 6, the graphic projection of measuring the printing opacity mark 702 of mask plate 7 is arrived picture side, make positive photoresist 802 sensitization on the transfer mask plate 8, note the image position of measuring figure on the mask plate 7; Transfer mask plate 8 stayed through developments, etching, at the chromium plating face of transfer mask plate 8 measure mask plate 7 through the picture of 2 one-tenth of projection objectives; If camera lens does not exist magnification error and distortion, then mark position should exist the camera lens of above-mentioned error then mark to be imaged on 804 places among Fig. 3 and Fig. 4 at nominal position 803 places.

Step S5: as shown in Figure 5, after being converted into the composition 805 that development can remove after the photoresist sensitization of 804 places, expose the chromium plating face 801 in this zone, method by etching, this a part of chromium is removed, form light-transmission type Transfer printing mark 807, finish the preparation of transfer mask plate 8 after removing photoresist, as shown in Figure 6.And the position of the Transfer printing mark 806 that in this process, records, 807 on transfer mask plate 8.The chromium plating face that to measure mask plate 7 applies positive photoresist, and chromium plating is faced illuminator 6 is installed in and holds on the blade unit 4, and the chromium plating face 801 of transfer mask plate 8 is installed on the board blade unit 5 to object lens 2;

Step S6: the chromium plating face 701 that will measure mask plate 7 as shown in Figure 7 again applies positive photoresist, chromium plating face 701 is installed to lighting unit and holds on the blade unit 4, the chromium plating face 801 of transfer mask plate 8 is installed on the board unit 5 down, according to the exposure dose of setting, open lighting unit 6, the graphic projection of transfer mask plate 8 is arrived picture side, make that measuring the positive photoresist sensitization and the process that apply on the mask plate 7 develops, etching, write down the transfer mask plate through the picture of 2 one-tenth of projection objectives at chromium plating face subscript, the chromium coating of measuring mask plate 7 this moment has comprised the initial position message of printing opacity mark and the positional information that 2 twice imaging are transmitted through projection objective; Part 703 after the sensitization is removed by development, carries out visually again, and the final magnification error that includes projection objective 2 and the measurement markers 704 after the distortion secondary action of forming simultaneously, measured on the mask plate 7 and also remained with initial measurement mark 702, as shown in Figure 8.

Step S7: measure the standard deviation of the positional information of the initial position message of each nominal position correspondence of printing opacity mark and the printing opacity mark that twice imaging in 2 backs are transmitted through projection objective by the alignment machine, as shown in Figure 9.Bring in the magnification error of projection objective 2 and the distortion model and find the solution, obtain magnification error and the distortion of projection objective 2.Wherein said position deviation has comprised the reading value dx of two orthogonal directionss _i, dy _i

Measure mask plate 7 mark (X _i, Y _i), then projection objective 2 backs of process multiplying power M are in picture side, and the nominal position of measuring mask plate 7 marks is

Usually multiplying power and the distortion error model of the projection objective 2 of multiplying power M can be expressed as:

${\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})=\mathrm{\&Delta;M}.\frac{X_i}{M}+{\mathrm{<figure-callout\; id="3"\; label="D"\; filenames="HDA00003460528100011.png"\; state="\{\{state\}\}">D</figure-callout>}}_3.\frac{X_i}{{\mathrm{<figure-callout\; id="3"\; label="M"\; filenames="HDA00003460528100011.png"\; state="\{\{state\}\}">M</figure-callout>}}^3}.(X_i^2+Y_i^2)$

${\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})=\mathrm{\&Delta;M}.\frac{X_i}{M}+{\mathrm{<figure-callout\; id="3"\; label="D"\; filenames="HDA00003460528100011.png"\; state="\{\{state\}\}">D</figure-callout>}}_3.\frac{Y_i}{M^3}.(X_i^2+Y_i^2)$

Wherein, dx _i, dy _iBe distributed as X, the position deviation of Y-direction, △ M is magnification error, D ₃Be the distortion of three rank, (X _i, Y _i) be the nominal position coordinate figure of object space measurement markers.

Then each mark position P (*) can be expressed as on the transfer mask plate 8:

$P(\frac{X_i}{M}+{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M}),\frac{Y_i}{M}+{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M}))$

Through behind the re-expose, the nominal position of measuring measurement markers new on the mask plate 7 can be expressed as:

$(\frac{X_i}{{\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="HDA00003460528100011.png,HDA00003460528100031.png"\; state="\{\{state\}\}">M</figure-callout>}}^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M},\frac{Y_i}{{\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="HDA00003460528100011.png,HDA00003460528100031.png"\; state="\{\{state\}\}">M</figure-callout>}}^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})$

Through behind the re-expose, the deviation of nominal position and physical location can be expressed as:

${\mathrm{dx}}_i(\frac{X_i}{{\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="HDA00003460528100011.png,HDA00003460528100031.png"\; state="\{\{state\}\}">M</figure-callout>}}^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M},\frac{Y_i}{{\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="HDA00003460528100011.png,HDA00003460528100031.png"\; state="\{\{state\}\}">M</figure-callout>}}^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})$

$=\mathrm{\&Delta;M}.(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})+{\mathrm{<figure-callout\; id="3"\; label="D"\; filenames="HDA00003460528100011.png"\; state="\{\{state\}\}">D</figure-callout>}}_3.(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M}).({(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})}^2+{(\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})}^2)$

${\mathrm{dy}}_i(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M},\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})$

$=\mathrm{\&Delta;M}.(\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})+{\mathrm{<figure-callout\; id="3"\; label="D"\; filenames="HDA00003460528100011.png"\; state="\{\{state\}\}">D</figure-callout>}}_3.(\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M}).({(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})}^2+{(\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})}^2)$

Get the initial measurement mark 702 of measuring each nominal position on the mask plate 7 and the position deviation 705 between the measurement markers 704 can be expressed as with alignment is machine-readable:

${\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M}){+\mathrm{dx}}_i(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M},\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})$

${\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M}){+\mathrm{dy}}_i(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M},\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})$

Consider the deviation T that re-expose placement mask plate may exist _x, T _y, R _z, R _xR _y, T wherein _x, T _yBe translational movement, R _zBe rotation amount, R _xR _yBe the match residual error, then measuring mark position deviation new on the mask plate 7 can be expressed as:

${\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M}){+\mathrm{dx}}_i(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M},\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})=$

${2T}_x+R_z.(\frac{Y_i}{M}+\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})+\mathrm{\&Delta;M}.(\frac{X_i}{M}+\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})+$

$D.(\frac{X_i}{M}+\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M}).({(\frac{X_i}{M}+\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})}^2+{(\frac{Y_i}{M}+\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})}^2)+R_x$

${\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M}){+\mathrm{dy}}_i(\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M},\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})=$

$T_y{+}^2{R}_z.(\frac{X_i}{M}+\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})+\mathrm{\&Delta;M}.(\frac{Y_i}{M}+\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})+$

$D.(\frac{Y_i}{M}+\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M}).({(\frac{X_i}{M}+\frac{X_i}{M^2}+\frac{{\mathrm{dx}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})}^2+{(\frac{Y_i}{M}+\frac{Y_i}{M^2}+\frac{{\mathrm{dy}}_i(\frac{X_i}{M},\frac{Y_i}{M})}{M})}^2)+R_y$

With twice mark departure of a series of nominal position and the nominal position coordinate figure substitution following formula of measuring, set up the least square fitting system of equations, find the solution T with Newton iteration method _x, T _y, R _z, △ M and D ₃Five parameters can obtain the magnification error of object lens to be measured and the measurement result of distortion.

Foregoing description only is the description to preferred embodiment of the present invention, is not any restriction to the scope of the invention, and any change that the those of ordinary skill in field of the present invention is done according to foregoing, modification all belong to the protection domain of claims.

Claims (10)

1. the pick-up unit of a projection objective magnification and distortion, it is characterized in that, described device comprises: frame unit, projection objective, fixed cell, hold blade unit, the board unit, lighting unit, measure mask plate and transfer mask plate, wherein: be placed with projection objective in the frame unit, fixed cell, hold blade unit, the lower surface that holds blade unit is placed on the surface of frame unit bottom, fixed cell is between projection objective and frame unit, fixedly connected with the inwall of frame unit in the outer face of fixed cell, the inner face of fixed cell is fixedlyed connected with the sidewall of projection objective; The bottom of transfer mask plate is positioned on the upper surface that holds blade unit; The chromium plating face of transfer mask plate has a distance near the bottom of projection objective between the chromium plating face of transfer mask plate and the bottom of projection objective; Opening part at frame unit is fixedlyed connected with the board unit, and board unit upper surface is connected with the lower surface of measuring mask plate; Lighting unit is positioned at measures the mask plate top, measures the chromium plating face of mask plate near the bottom of lighting unit, and has a distance between the chromium plating face of the bottom of lighting unit and measurement mask plate.

2. the pick-up unit of projection objective magnification and distortion according to claim 1 is characterized in that described transfer mask plate is the mask plate that does not have figure, applies positive photoresist at the chromium plating face of transfer mask plate.

3. the pick-up unit of projection objective magnification and distortion according to claim 1 is characterized in that, the chromium plating of the positive photoresist that described transfer mask plate scribbles faces lighting unit and is installed in and holds on the blade unit.

4. the pick-up unit of projection objective magnification and distortion according to claim 1, it is characterized in that, regulate the height of described projection objective and board unit, make to measure mask plate and transfer mask plate and be in separately with respect to the nominal position of projection objective, realize the image conjugation.

5. as the pick-up unit of projection objective magnification as described in the claim 4 and distortion, it is characterized in that, chromium plating face at described measurement mask plate forms a plurality of printing opacity marks, and the printing opacity mark is lattice-shaped and is distributed in the projection objective field range to be measured, and records the nominal position of each printing opacity mark.

6. as the pick-up unit of projection objective magnification as described in the claim 5 and distortion, it is characterized in that, the graphic projection of printing opacity mark of measuring mask plate to picture side, is made the positive photoresist sensitization of transfer mask plate, note the image position of figure on the measurement mask plate; The transfer mask plate stayed through development, etching, at the chromium plating face of transfer mask plate measure the picture that mask plate becomes through projection objective.

7. as the pick-up unit of projection objective magnification as described in the claim 5 and distortion, it is characterized in that, the chromium plating face of measuring mask plate applies positive photoresist, and chromium plating faces lighting unit and be installed in and hold on the blade unit, and the chromium plating of transfer mask plate is installed on the board blade unit towards projection objective.

8. as the pick-up unit of projection objective magnification as described in the claim 5 and distortion, it is characterized in that, according to the exposure dose of setting, open described lighting unit, the graphic projection of transfer mask plate is arrived picture side, make the photoresist sensitization of measuring mask plate also through development, etching, write down the picture that the transfer mask plate becomes through projection objective at chromium plating face subscript, the chromium coating of measuring mask plate has at this moment comprised the initial position message of printing opacity mark and the positional information that twice imaging transmitted through projection objective.

9. as the pick-up unit of projection objective magnification as described in the claim 5 and distortion, it is characterized in that, measure the standard deviation of the positional information of the initial position message of each nominal position correspondence of printing opacity mark and the printing opacity mark that twice imaging transmitted through projection objective by the alignment machine, bring in projection objective magnification error and the distortion model and find the solution, obtain magnification error and distortion.

10. the detection method of a projection objective magnification and distortion, it is applied in the pick-up unit of projection objective magnification and distortion, described device comprises frame unit, projection objective, fixed cell, holds blade unit, board unit, lighting unit, measurement mask plate and transfer mask plate, it is characterized in that described method comprises the following steps

Step S1: prepare one and measure mask plate, form a plurality of printing opacity marks at the chromium plating face of measuring mask plate, the printing opacity mark is lattice-shaped and is distributed in the projection objective field range to be measured, and records the nominal position of each printing opacity mark;

Step S2: get a mask plate that does not have figure as the transfer mask plate, apply positive photoresist at the chromium plating face of transfer mask plate, obtain to scribble the chromium plating face of positive photoresist;

Step S3: the chromium plating that will measure mask plate faces projection objective and is installed on the board unit; The chromium plating of the positive photoresist that the transfer mask plate is scribbled faces lighting unit and is installed in and holds on the blade unit; Regulate the height of projection objective and board unit, make that measuring mask plate and transfer mask plate is in separately with respect to the nominal position of projection objective, realizes the image conjugation;

Step S4: according to setting exposure dose, open lighting unit and begin illumination, the graphic projection of measuring the printing opacity mark of mask plate is arrived picture side, make the positive photoresist sensitization of transfer mask plate, note the image position of measuring figure on the mask plate; The transfer mask plate stayed through development, etching, at the chromium plating face of transfer mask plate measure the picture that mask plate becomes through projection objective;

Step S5: the chromium plating face that will measure mask plate applies positive photoresist, and chromium plating is faced lighting unit is installed in and holds on the blade unit, and the chromium plating of transfer mask plate is installed on the board blade unit towards projection objective;

Step S6: according to the exposure dose of setting, open lighting unit, the graphic projection of transfer mask plate is arrived picture side, make the photoresist sensitization of measuring mask plate also through development, etching, write down the picture that the transfer mask plate becomes through projection objective at chromium plating face subscript, the chromium coating of measuring mask plate this moment has comprised the initial position message of printing opacity mark and the positional information that twice imaging transmitted through projection objective;

Step S7: the standard deviation of measuring the positional information of the initial position message of each nominal position correspondence of printing opacity mark and the printing opacity mark that twice imaging transmitted through projection objective by the alignment machine, bring in projection objective magnification error and the distortion model and find the solution, obtain magnification error and distortion.

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