CN106569390A - A projection exposure device and method - Google Patents

Abstract

A projection exposure device is provided. The device includes a lighting source, a mask plate, a mask table, a base plate, a workbench and a control system in order. Each exposure zone is provided with aligning focal plane measuring system and a projection objective group which are side by side and are between the mask table and the base plate. The aligning focal plane measuring system is used for performing focal surface measurement at the same time of alignment measurement on the mask plate and the base plate before a scanning exposure process or in a scanning exposure process. A projection exposure method is also provided. An original coordinate and a compensation quantity of each alignment mark are calculated and added to obtain a compensated coordinate, the relative positions of the mask plate and the base plate are calculated, and the workbench is moved for compensation, thus completing position and focal plane alignment. The device and the method have advantages of a simple structure, low occupied space and high precision.

Description

A kind of projection aligner and method

Technical field

The present invention relates to semiconductor lithography field, more particularly to a kind of projection aligner and method.

Background technology

TFT (Thin Film Transistor) is the abbreviation of TFT, is one Plant the large-scale semiconductive completely inegrated circuit manufacturing technology using new material and new technology.TFT is By sputtering, chemical deposition process shape on the on-monocrystalline such as glass or plastic base piece or chip The various films into necessary to manufacture circuit, by the integrated electricity of processing and fabricating large-scale semiconductive to film Road.It is increasing to the dimensional requirement of TFT with the development of associated electrical consumer product, Integrated unit is more and more, and single illuminator is difficult the demand for meeting TFT photoetching.It is logical It is often general using the maximum illumination field of view in the stepping lithographic equipment such as IC manufacturing, encapsulation For 8 inches, scanning photoetching also simply has bigger visual field in scanning direction, is typically also less than 10 inches.But present five TFT exposure fields more than generation are all more than 17 inches, single The illumination field of view of camera lens far can not meet the requirement of big visual field photoetching, so many field stitchings are swept Retouch projection mask aligner just to arise at the historic moment, it solves well large-area element manufacturing and yield Between contradiction, be widely used in the production of large-scale semiconductor device, flat pannel display, thin film.

Many object lens, the Overlap-scanning of many visual fields to putting forward higher requirement to Barebone, because expose The area increase of optical device, is to realize that accurately alignment needs to arrange multiple alignment visual field points.It is existing There is the alignment and focal plane measurement system disclosed in technology for a kind of many field stitching exposure devices System, its structure mainly includes that a lighting source, multiple illuminators, mask plate, mask are carried Thing platform, multiple projection optical systems, sensitive substrate, substrate object stage, in mask plate both sides also Several moving lens and laser interferometer are provided with, are also set between each exposure area of mask plate Mask detecting system is put, substrate detecting system is also set up between multiple projection optical systems, is adjusted Positive system, also including control device, control device respectively with all illuminators, all projections It is optical system, all moving lens, all laser interferometer, all mask detecting systems, all Substrate detecting system and all Autocorrection System of Conveyor-belt and substrate object stage, the connection of mask object stage circuit, By the way that the pattern for needing exposure is divided into into several exposure areas, carry out in each exposure area Alignment and scan exposure, while alignment and scan exposure, the mask inspection of each region both sides Examining system, substrate detecting system and Autocorrection System of Conveyor-belt detect respectively the parameter exposed in one's respective area, Guarantee that the exposure in each region is precisely carried out, join with exposure of the timed unit to each region Number is modified, further the precision of raising exposure, but this exposure device and exposure side Method exist problem be：In this exposure device, it is responsible for substrate with mask plate position alignment Device not is same device with the device that responsible focal plane is aligned, in semiconductor fabrication processes, Substrate can because be heated or discontinuity and produce different degrees of warpage, and by photosensitive The impact of substrate warp, in exposure, position alignment and focal plane are not to the focal plane that Barebone is surveyed Not on the same face, therefore measurement result is affected, and within each exposure area, Multiple moving lens, laser interferometer, substrate detecting system and tune will be set on substrate Positive system so that the motility of space layout is reduced, it is therefore necessary to invention it is a kind of it is easy to operate, Simple structure, the little, high precision that takes up room and the exposure device suitable for big visual field photoetching or Exposure method.

The content of the invention

To solve the above problems, the present invention proposes a kind of projection aligner and method, every Individual exposure area is only using single alignment focal plane measuring system, you can in same substrate height face It is upper to carry out position alignment and focal plane alignment simultaneously, easy to operate, simple structure and take up room Little, precision is high, improve the motility of measuring system space layout.

To reach above-mentioned purpose, the present invention provides a kind of projection aligner, includes successively：

One lighting source；

One lamp optical system；

Mask stage, for carrying mask plate；

Projection objective group；

Work stage, for carrying a substrate, during scan exposure, what the light source occurred Light beam, through the lamp optical system, is irradiated on the mask plate, and will be arranged on institute The pattern of mask plate is stated, through the projection objective, is transferred on the substrate；

And the control system being connected with mask stage circuit,

The projection aligner also includes alignment focal plane measuring system, is arranged on the mask stage And the work stage between, during crossing Cheng Qian or scan exposure in the scan exposure, While carrying out the mask plate and the substrate to locating tab assembly, the focal plane of the substrate is carried out Measurement.

Preferably, the substrate is divided into several exposure areas, in each exposure region The alignment focal plane measuring system and the projection objective group are designed with domain.

Preferably, the alignment focal plane measuring system is connected with the control system circuit, institute Stating alignment focal plane measuring system includes several alignment focal plane measuring units, and each described alignment is burnt Interface measurement unit is successively including area array cameras, the first image-forming assembly, Amici prism and the second one-tenth As component, also include the first light fixture, diaphragm and the second light fixture successively, described first Light fixture is connected with the Amici prism light path, second light fixture and the illumination light Source light path connects.

Preferably, the centrally disposed light hole of the diaphragm, in the light hole surrounding four are arranged Individual slit, four slits are in a center of symmetry with regard to the diaphragm center, four slits It is generally circular in shape or square.

Preferably, the diaphragm be four slits with the light hole apart from adjustable Structure.

Preferably, being provided with shutter between the diaphragm and second light fixture.

Preferably, the lighting source is with two waveband Halogen light or two waveband LED, And it is provided with annular filter wave plate between the diaphragm and second light fixture.

Preferably, the projection objective group is provided with several projection objectives, the projection objective Group is provided with public focal plane.

Preferably, the lighting source is single-range Halogen light or single-range LED, The lighting source has the optical band for avoiding photo resist photosensitive.

Preferably, the baseplate material is glass or silica-base material.

Preferably, the upper surface of base plate is provided with alignment mark, the alignment mark number is Two or more, the mask plate surface is provided with mask alignment mark, the mask alignment mark Number is two or more.

Preferably, when the mask plate is aligned with the substrate position, in each exposure In light region, an alignment mark group is at least shown in the control system, it is described to fiducial mark Note group is the image that an alignment mark overlaps with a mask alignment mark center.

The present invention also provides a kind of exposure method, including alignment actions and exposure actions, Alignment focal plane measuring system is set in each exposure area, when alignment actions are carried out, by moving Dynamic work stage is recorded in each described alignment focal plane measuring unit so as to drive the movement of datum plate Hot spot circle radius change, calculate each it is described alignment focal plane measuring unit under the workpiece Platform at an arbitrary position when relative to projection objective group public focal plane vertical offset and institute The inclined light shaft that work stage goes up at an arbitrary position is stated, then the light of the work stage on optional position Axle is inclined and vertical offset of the work stage relative to the public focal plane on the position Product be the compensation dosage of the alignment mark on each described datum plate, and by each to fiducial mark The coordinate of note is compensated, and the compensation coordinate of each alignment mark is obtained after compensation, is then passed through The compensation coordinate of each alignment mark calculates presently described substrate with the mask plate Position relationship, the movement work stage so that the substrate is aligned with the mask plate, then It is exposed action.

Preferably, the method is comprised the following steps：

Step one：When carrying out alignment actions, lighting source is opened, arbitrarily select an exposure region The work stage is moved by the described first exposure by control system as the first exposure area in domain Zone level is moved in the field range of the alignment focal plane measuring system, and calculating is now carried The mask stage of the mask plate and the relative position relation of the work stage；

Step 2：The work stage is moved horizontally by the control system, by datum plate movement To the alignment focal plane measuring system field range, in each alignment focal plane measuring unit Interior, the light that the lighting source sends sequentially passes through the in the alignment focal plane measuring system Two light fixtures, diaphragm, the first light fixture, Amici prism, the second image-forming assembly reach institute State and formed on substrate the reflected beams, the reflected beams sequentially pass through second image-forming assembly, The Amici prism, the first image-forming assembly, are finally imaged to the alignment focal plane measuring system Area array cameras on, through the diaphragm four slits light then on the area array cameras Form four hot spots, using with four spot centers all equal points of distance as the center of circle, with The distance of any one of spot center is hot spot circle as the circle that radius is formed；

Step 3：The work stage is vertically moved by the control system so that the datum plate Upper surface is located at the public focal plane of the projection objective group, then now each described alignment focal plane is surveyed Hot spot circle in amount unit is standard hot spot circle, and the control system is recorded and preserves described Standard hot spot circle half in the position coordinateses of work stage and each described alignment focal plane measuring unit Footpath r₀；

Step 4：The work stage is arbitrarily vertically moved by the control system, record is mobile every time The position coordinateses of Shi Suoshu work stages are directed at the hot spot in focal plane measuring unit with each described Round radius, the calculating work stage vertically moves position coordinateses change and Jiao is directed at each described Then the relation of the hot spot radius of circle change calculates each described alignment in interface measurement unit Under focal plane measuring unit the work stage at an arbitrary position when relative to the public focal plane hang down Straight side-play amount；

Step 5：The work stage is arbitrarily vertically moved by control system, the control system according to The coordinate position of the work stage calculates each described alignment focal plane measurement list when mobile every time The inclined light shaft expression formula that light path is present in first, then the control system is by the inclined light shaft Inclined light shaft when expression formula calculates the work stage at an arbitrary position；

Step 6：The work stage is moved horizontally by the control system, by first exposure region All described alignment mark in domain is moved in the field range of the alignment focal plane measuring system, And the horizontal position coordinate of all alignment marks is obtained as original coordinate；

Step 7：According to step 4, the control system calculate each described alignment mark relative to The vertical offset of the public focal plane, according to step 5, calculates each described alignment mark Inclined light shaft, then the vertical shift of the control system according to each alignment mark Amount and the inclined light shaft are compensated to original coordinate, the horizontal position coordinate after compensation To compensate coordinate；

Step 8：The control system is according to the compensation coordinate of the alignment mark is calculated The relative position relation of substrate and the work stage, and by covering described in calculating in step one Film platform calculates the mask plate with the substrate with the relative position relation of the work stage Relative position relation, the then relative position that the control system passes through the mask plate and the substrate Put relation and move the work stage or the mask stage, until showing in the control system Alignment mark group described at least one, and while show that focal plane is aligned, then alignment actions are complete Into；

Step 9：When being exposed action, the scan exposure program opened in the control system is clicked on, Scan exposure starts, and while the movement work stage and the mask stage, in moving process The middle aligned relationship for keeping the substrate to be formed in step 7 with the mask plate, until exposure Action is completed；

Step 10：After the completion of the exposure of first exposure area, according to step one to step 9 one by one Alignment actions and exposure actions are carried out to exposure area remaining described.

Preferably, the horizontal coordinate of four spot centers is respectively described in step 2 (xa, ya), (xb, yb), (xc, yc), (xd, yd), the then horizontal coordinate of the round heart of the hot spot The computing formula of (x_ce, y_ce) is The radius that then hot spot is justified

Preferably, the computational methods of four spot centers are based on the center of gravity of gradation of image Method or the geometrical center method based on pattern edge.

Preferably, work stage described in step 4 vertically moves position coordinateses change and each institute The relation for stating the hot spot radius of circle change in alignment focal plane measuring unit is that focal plane corrects machine Constant, then the control system is according to each focal plane for being directed at focal plane measuring unit Correction machine constantWith the standard hot spot radius of circle r₀Calculate each described alignment focal plane to survey Amount unit under the work stage at an arbitrary position when relative to the public focal plane vertical shift Amount.

Preferably, the work stage exists under each described alignment focal plane measuring unit in step 4 Relative to the vertical offset of the public focal plane during optional position

Preferably, four vertical positions for arbitrarily moving the work stage are to coordinate in step (x1, y1, z1), it is (x2, y2, z2) that vertical position to the vertical coordinate of the work stage is arbitrarily moved in continuation, The focal plane corrects machine constantWherein r1 is (x1, y1, z1) corresponding described hot spot Round radius, r2 is the radius of (x2, y2, z2) the corresponding hot spot circle.

Preferably, the inclined light shaft of each the alignment focal plane measuring unit in step 5 is (θ_Ry,θ_Rx), and

Preferably, the described original coordinate in step 5 is (x, y), the benefit in step 6 Coordinate is repaid for (X, Y), wherein X=x+ Δs Z × θ_Ry, Y=y+ Δs Z × θ_Rx。

Compared with prior art, the invention has the beneficial effects as follows：The present invention provides a kind of projection and exposes Electro-optical device, includes successively：One lighting source；One lamp optical system；Mask stage, for holding Carry mask plate；Projection objective group；Work stage, for carrying a substrate, in scan exposure process In, the light beam that the light source occurs, through the lamp optical system, is irradiated to the mask In version, and the pattern of the mask plate will be arranged on, through the projection objective, be transferred to institute State on substrate；And the control system being connected with mask stage circuit, the projection aligner is also Including alignment focal plane measuring system, it is arranged between the mask stage and the work stage, is used for During the scan exposure crosses Cheng Qian or scan exposure, to the mask plate and the substrate While carrying out to locating tab assembly, the focal plane measurement of the substrate is carried out.This avoid using many Individual machine carries out respectively measuring locating tab assembly and focal plane for substrate, simplifies device.

The present invention also provides a kind of exposure method, in each exposure area, is carrying out During alignment actions, first datum plate is moved in the field range of alignment focal plane measuring system, is appointed Meaning vertically moves work stage and obtains Workpiece stage vertical position change under each alignment focal plane measuring unit Change the variation relation with hot spot radius of circle, then calculate the public affairs in projection objective group when substrate During confocal face, the radius of the standard hot spot circle in each alignment focal plane measuring unit thus may be used During calculating work stage at an arbitrary position, upper surface of base plate is in each alignment focal plane measuring unit The interior vertical offset relative to public focal plane, then arbitrarily vertically moves work stage, calculates every The inclined light shaft expression formula of individual alignment focal plane measuring unit, then will be all right in exposure area Fiducial mark note is moved in alignment focal plane measuring system field range, is calculated each alignment mark and is existed Relative to the vertical offset and inclined light shaft of public focal plane in each alignment focal plane measuring unit, And both products are calculated into the coordinate compensation dosage of each alignment mark, each is to fiducial mark The former horizontal coordinate of note adds respective coordinate compensation dosage, obtains the compensation coordinate of each alignment mark, The relative position relation of now substrate and mask plate is calculated by compensating coordinate, and is controlled System travelling workpiece platform or mask stage in control system until show at least one pair of fiducial mark Note group, and display base plate is aligned with mask plate position, then substrate and mask plate position and focal plane All it is aligned, action is exposed after the completion of alignment actions, after the completion of the exposure area exposure, One by one remaining exposure area is aligned and is exposed.The present invention is by single exposure area It is interior that alignment focal plane measuring system is set, each alignment focal plane measuring unit is calculated by datum plate Correlation coefficient, then calculate the compensation dosage of each alignment mark, and by each alignment mark Coordinate is compensated, and the coordinate of actual each alignment mark is obtained, then by each to fiducial mark The coordinate of note calculates the relation of front substrate and mask plate, then travelling workpiece platform so that base Plate is aligned with mask plate, and so position alignment is aligned together with focal plane in alignment focal plane measuring system Shi Jinhang, and measured and adjustment based on same plane, therefore precision is higher, only sets Putting single alignment focal plane measuring system and avoiding arranging multiple devices carries out respectively position alignment and Jiao In the face of standard therefore easy to operate, simple structure, take up room that little, precision is high, improve The advantage of the motility of measuring system space layout.

Description of the drawings

Fig. 1 is the exposure device structural representation of the embodiment of the present invention one；

Fig. 2 is each the alignment focal plane measuring unit structural representation of the embodiment of the present invention one；

Fig. 3 is that light path trend is shown in each alignment focal plane measuring unit in the embodiment of the present invention one It is intended to；

Fig. 4 is diaphragm right view in the embodiment of the present invention one；

Fig. 5 is the four hot spot schematic diagrams formed on area array cameras in the embodiment of the present invention one；

Fig. 6 is that datum plate is moved to into alignment focal plane measuring system visual field in the embodiment of the present invention one Interior schematic diagram；

Fig. 7 is inclined light shaft schematic diagram in the embodiment of the present invention one；

Fig. 8 is original coordinate schematic diagram on area array cameras in the embodiment of the present invention one；

Fig. 9 is the exposure method flow chart of the embodiment of the present invention one；

Figure 10 is to measure the first line flag schematic diagram in the embodiment of the present invention one；

Figure 11 is to measure the second line flag schematic diagram in the embodiment of the present invention one；

Figure 12 is that focal plane measuring unit structural representation is directed in the embodiment of the present invention two；

Figure 13 is that focal plane measuring unit structural representation is directed in the embodiment of the present invention three.

In figure：1- lighting sources, 2- mask plates, 3- mask stages, 4- work stages, 5- substrates, The alignment marks of 501- first, the alignment marks of 502- second, the alignment marks of 503- the 3rd, 504- Four alignment marks, the alignment marks of 505- the 5th, the alignment marks of 506- the 6th, 507- the 7th is aligned Labelling, the exposure areas of 510- first, 511- the first row alignment marks, the rows of 512- second are to fiducial mark Note, the exposure areas of 520- second, the exposure areas of 530- the 3rd, the exposure areas of 540- the 4th, 6- Datum plate, 7- projection objective groups, 8- alignment focal plane measuring systems, the alignment focal planes of 801- first are surveyed Amount unit, the alignment focal plane measuring units of 802- second, the alignment focal plane measuring units of 803- the 3rd, 804- the 4th is directed at focal plane measuring unit, the alignment focal plane measuring units of 805- the 5th, 806- the 6th Alignment focal plane measuring unit, the alignment focal plane measuring units of 807- the 7th, 810- area array cameras, 820- First image-forming assembly, 830- Amici prisms, 840- diaphragms, 841- light holes, 842- slot sets, The light fixtures of 850- first, the light fixtures of 860- second, the image-forming assemblies of 870- second, 880- is fast Door, 890- annular filter wave plates；

R- hot spot radius of circles.

Specific embodiment

It is understandable to enable the above objects, features and advantages of the present invention to become apparent from, tie below Close accompanying drawing to be described in detail the specific embodiment of the present invention.

Embodiment one

Fig. 1, Figure 10, Figure 11 are refer to, the present invention provides a kind of projection aligner, according to It is secondary including：Lighting source 1, mask plate 2, mask stage 3, substrate 5, work stage 4 and control System (not shown) processed, is provided with datum plate 6, typically by base on the table top of the work stage 4 Quasi- plate 6 is placed on the side of work stage 4, and substrate 5 is square, the length of datum plate 6 With the equal length of substrate 5.In the case where the area of substrate 5 is very big, substrate 5 is divided into Several exposure areas, such as 4 exposure areas, respectively the first exposure area 510, Two exposure areas 520, the 3rd exposure area 530 and the 4th exposure area 540, it is so corresponding Ground, according to the division principle of substrate 5, mask plate 2 can also be divided into four identical regions, During exposure, will be once aligned and be exposed in each region, four areas are then completed one by one The alignment in domain and exposure, this is because due to the area of substrate 5 it is very big, and through loaded down with trivial details preamble After processing, substrate 5 defines surface the shape of projection or depression, if by whole substrate 5 disposable whole faces expose, and the position generation that some must be made raised or be recessed more serious is larger Error, therefore using subregion be aligned and expose, it is possible to increase the exposure in each region is accurate Degree.

It is preferred that refer to Figure 10, the material of the substrate 5 is glass or silica-base material, The upper surface of the substrate 5 is provided with alignment mark, and the alignment mark number is two or more, In each exposure area, some row alignment marks are provided with, such as in the first exposure area 510 It is provided with two row alignment marks, respectively the row alignment mark of the first row alignment mark 511 and second 512, several alignment marks are provided with per a line, such as the first row alignment mark 511 is provided with seven Alignment mark, the surface of the mask plate 2 is provided with mask alignment mark (not shown), described to cover Mould alignment mark number is two or more, when the mask plate 2 and the position alignment of the substrate 5 When, in each described exposure area, one is at least shown in the control system to fiducial mark Note group (not shown), the alignment mark group be an alignment mark with cover described in one The image of film alignment mark center superposition.

All it is provided with alignment focal plane measuring system 8 and projection side by side in each described exposure area Objective lens 7, and the alignment focal plane measuring system 8 and the projection objective group 7 are located at institute State between mask stage 3 and the substrate 5.

The control system respectively with it is described be aligned focal plane measuring system 8, the mask stage 3, The circuit of the work stage 4 connects.In alignment or exposure process, focal plane measuring system is directed at 8th, the real time data of mask stage 3 and work stage 4 be also by circuit transmission to control system, Control system is additionally provided with itself simulation software, for analyzing and processing data, works as Data Analysis Services After the completion of then send movement directive to mask stage 3 and work stage, then mask stage 3 and work stage 4 The movement in horizontally or vertically direction is realized according to the order of control system.

It is preferred that the projection objective group 7 is provided with several projection objectives, the projection objective Group 7 is provided with public focal plane, when all of in certain exposure area on the upper surface of the substrate 5 When point is all located at public focal plane, then control system is regarded as the exposure area focal plane and is aligned.

Fig. 2, Fig. 6, Figure 10 are refer to, usually, if alignment focal plane measuring system 8 is provided with Dry alignment focal plane measuring unit, such as 7, the respectively first alignment focal plane measuring unit 801st, the second alignment focal plane measuring unit the 802, the 3rd is directed at focal plane measuring unit the 803, the 4th Alignment focal plane measuring unit the 804, the 5th is directed at focal plane measuring unit the 805, the 6th and is directed at focal plane The alignment focal plane of measuring unit the 806, the 7th measuring unit 807, each alignment focal plane measuring unit Include area array cameras 810, the first image-forming assembly 820, Amici prism 830 and second successively Image-forming assembly 870, also includes successively that the first light fixture 850, diaphragm 840 and second are illuminated Component 860, first light fixture 850 is connected with the light path of the Amici prism 830, institute State the second light fixture 860 to be connected with the light path of the lighting source 1.

Fig. 3 is refer to, in each described alignment focal plane measuring unit, light path trend is described The light that lighting source 1 sends sequentially pass through second light fixture 860, the diaphragm 840, First light fixture 850, the Amici prism 830, second image-forming assembly 870 Reach and the reflected beams are formed on the substrate 5, the reflected beams sequentially pass through the second imaging group Part 870, the Amici prism 830, first image-forming assembly 820, are finally imaged to institute State on area array cameras 810.

It is preferred that Fig. 4 is refer to, the centrally disposed light hole 841 of the diaphragm 840, in institute State the surrounding of light hole 841 and slot set 842 is set, slot set 842 includes four slits, slit Group is 842 in a center of symmetry with regard to the center of the diaphragm 840, four shape of slit be all circle or Person is square.Slot set 842 can be adjusted with the distance of the light hole 841.

It is preferred that the lighting source 1 is single-range Halogen light or single-range LED, The lighting source 1 has the optical band for avoiding photo resist photosensitive.

Fig. 9 is refer to, the present invention also provides a kind of projection using above-mentioned projection aligner Exposure method, including alignment actions and exposure actions, the method is comprised the following steps：

Step one：When carrying out alignment actions, the lighting source 1 is opened, when being exposed, exposed The exposure order in light region is arbitrary, and the present embodiment selects first to expose the first exposure area 510, In the first exposure area 510, substrate 5 is provided with two row alignment marks, respectively the first row The row alignment mark 512 of alignment mark 511 and second, is provided with the first row alignment mark 511 7 alignment marks, respectively the first alignment mark 501, the second alignment mark the 502, the 3rd Alignment mark 503, the 4th alignment mark 504, the 5th alignment mark 505, the 6th pair of fiducial mark The 506, the 7th alignment mark 507 of note, moves the work stage 4 by the first exposure area 510 It is moved horizontally in the field range of the alignment focal plane measuring system 8, i.e., is aligned at each In focal plane measuring unit, can show on area array cameras 810 in first exposure area 510 Alignment mark, calculate the relative position relation of the now mask stage 3 and the work stage 4, In whole exposure device, using vertically upward direction as Z axis, horizontal plane be then by X, The plane of Y-axis composition, then as (x, y), three-dimensional coordinate is (x, y, z) to the horizontal coordinate of a point； Step 2：Fig. 6 is refer to, the work stage 4 is moved horizontally by the control system, will The datum plate 6 is moved in the field range of alignment focal plane measuring system 8, refer to figure 5, through the light then shape on the area array cameras 810 of four slits of the diaphragm 840 Into four hot spots, as the center of circle, and appoint using with four spot centers all equal points of distance The distance of one spot center of meaning is hot spot circle as the circle that radius is formed.

It is preferred that control system can be according to the centroid method based on gradation of image or based on figure The geometrical center method at edge calculates the center of four hot spots, and the level of this four spot centers is sat Mark is respectively (xa, ya), (xb, yb), (xc, yc), (xd, yd), then the horizontal coordinate of the round heart of hot spot The computing formula of (x_ce, y_ce) is The radius that then hot spot is justified

Step 3：The work stage 4 is vertically moved by control system so that the datum plate 6 Upper surface is located at the public focal plane, then institute now in each described alignment focal plane measuring unit Hot spot circle is stated for standard hot spot circle, the control system records and preserve the position of the work stage 4 Put the standard hot spot radius of circle r in coordinate and each alignment focal plane measuring unit₀, in the present embodiment First alignment focal plane measuring unit 801, second is directed at focal plane measuring unit the 802, the 3rd and is aligned The alignment focal plane of focal plane measuring unit the 803, the 4th measuring unit the 804, the 5th is directed at focal plane measurement The alignment focal plane of unit the 805, the 6th measuring unit the 806, the 7th is directed at focal plane measuring unit 807 The standard hot spot radius of circle for measuring is respectively r0A, r0B, r0C, r0D, r0E, r0F, r0G；

Step 4：The work stage 4 is arbitrarily vertically moved by control system, such as moves two It is secondary, it is for the first time mobile after in work stage 4 three-dimensional coordinate of certain point be (x1, y1, z1), work stage Three-dimensional coordinate of the same point after second mobile is (x2, y2, z2) on 4, and record is each time The radius that the hot spot is justified in each described alignment focal plane measuring unit when mobile, respectively r1, R2, the calculating work stage 4 vertically moves position coordinateses change and focal plane survey is directed at each described The relation of the hot spot radius of circle change in amount unit, i.e. each described alignment focal plane measuring unit Focal plane correction machine constantFirst alignment focal plane measuring unit in the present embodiment 801st, the second alignment focal plane measuring unit the 802, the 3rd is directed at focal plane measuring unit the 803, the 4th Alignment focal plane measuring unit the 804, the 5th is directed at focal plane measuring unit the 805, the 6th and is directed at focal plane The standard hot spot radius of circle point that the alignment focal plane of measuring unit the 806, the 7th measuring unit 807 is measured It is notThen the control system is according to each The focal plane correction machine constant of the alignment focal plane measuring unitWith the standard hot spot Radius of circle r₀Calculate each it is described alignment focal plane measuring unit under the work stage 4 in any position Relative to the vertical offset of the public focal plane when puttingWherein r is workpiece The hot spot radius of circle at the optional position of platform 4, that is to say, that no matter which work stage 4 moves to Individual position, as long as measure each being aligned in focal plane measuring unit in hot spot radius of circle at that time, i.e., Can calculate at the position, the vertical shift of work stage 4 in each alignment focal plane measuring unit Amount；

Step 5：Fig. 7 is refer to, lighting source 1 is burnt by projection objective group 7 and alignment When planar survey system 8 reaches 5 surface of substrate, its level detection branch road can produce inclined light shaft, That is when the level of alignment mark is detected to position, due to the impact of out of focus, to fiducial mark Note can produce translation when imaging is to area array cameras 810, cause the horizontal coordinate for detecting not Accurately, but because this inclined light shaft is the system deviation produced by whole exposure device, therefore By inclined light shaft when calculating inclined light shaft, and subsequently calculating each alignment mark horizontal coordinate This deviation can be corrected in compensation.Computational methods are：Arbitrarily vertically moved by control system The dynamic work stage 4, such as move twice, certain point in work stage 4 after moving for the first time Three-dimensional coordinate is (x3, y3, z3), three-dimensional of the same point after second mobile in work stage 4 Coordinate is (x4, y4, z4), then the inclined light shaft expression formula of each alignment focal plane measuring unit is

Step 6：The work stage 4 is moved horizontally by the control system, by the described first exposure All described alignment mark in region 510 moves into the visual field of the alignment focal plane measuring system 8 In the range of, Figure 10 is refer to, alignment focal plane measuring system 8 first measures the first row alignment mark 511, Fig. 8 is refer to, each coordinate in the first row alignment mark 511 is in area array cameras The horizontal coordinate shown on 810 continues referring to Figure 10 as original coordinate, each alignment Each labelling in focal plane measuring unit alignment the first row alignment mark 511, that is to say, that the One alignment focal plane measuring unit 801, second is directed at focal plane measuring unit the 802, the 3rd and is directed at burnt It is single that the alignment focal plane of interface measurement unit the 803, the 4th measuring unit the 804, the 5th is directed at focal plane measurement Unit the 805, the 6th is directed at focal plane measuring unit the 806, the 7th and is directed at 807 points of focal plane measuring unit Do not measure the first alignment mark 501, the second alignment mark 502, the 3rd alignment mark 503, 4th alignment mark 504, the 5th alignment mark 505, the 6th alignment mark 506, the 7th pair Fiducial mark note 507, the original coordinate for obtaining be respectively (xA, yA), (xB, yB), (xC, yC), (xD, yD), (xE,yE)、(xF,yF)、(xG,yG)；

Step 7：According to step 4, the control system calculate each described alignment mark relative to The vertical offset of the public focal plane, difference is as follows：

Wherein Δ ZA, Δ ZB, Δ ZC, Δ ZD, Δ ZE, Δ ZF, Δ ZG The each self-corresponding vertical offset of 501 to the 7th alignment mark of respectively the first alignment mark 507, AndRespectively first alignment focal plane measuring unit The each self-corresponding focal plane correction machine constant of 801 to the 7th alignment focal plane measuring unit 807, rA, RB, rC, rD, rE, rF, rG are respectively the first alignment focal plane measuring unit 801 to Seven alignment focal plane measuring units 807 each measure respectively the alignment of the first alignment mark 501 to the 7th Hot spot radius of circle resulting during labelling 507, and r0A, r0B, r0C, r0D, r0E, r0F, R0G is respectively the alignment focal plane of the first alignment focal plane measuring unit 801 to the 7th measuring unit 807 Respective standard hot spot radius of circle.

According to step 5, the light of the alignment mark 507 of the first alignment mark 501 to the 7th is calculated Axle is inclined, respectively：(θ_RyA,θ_RxA), (θ_RyB,θ_RxB), (θ_RyC,θ_RxC), (θ_RyD,θ_RxD), (θ_RyE,θ_RxE), (θ_RyF,θ_RxF), (θ_RyG,θ_RxG), then the control system according to each The vertical offset and the inclined light shaft of alignment mark is mended to original coordinate Repay, be specifically expressed from the next：

XA=xA+ Δs ZA × θ_RyA, YA=YA+ Δ ZA* θ_RxA；

XB=xB+ Δs ZB × θ_RyB, YB=YB+ Δ ZB* θ_RxB；

XC=xC+ Δs ZC × θ_RyC, YC=YC+ Δ ZC* θ_RxC

XD=xD+ Δs ZD × θ_RyD, YD=YD+ Δ ZD* θ_RxD；

XE=xE+ Δs ZE × θ_RyE, YE=YE+ Δ ZE* θ_RxE；

XF=xF+ Δs ZF × θ_RyF, YF=YF+ Δ ZF* θ_RxF；

XG=xG+ Δs ZG × θ_RyG, YG=YG+ Δ ZG* θ_RxG, wherein (XA, YA), (XB, YB), (XC, YC), (XD, YD), (XE, YE), (XF, YF), (XG, YG) are respectively the first alignment mark 501 to The respective compensation coordinate of seven alignment mark 507.

Figure 11 is refer to, when calculating all of alignment mark of the first row alignment mark 511 After compensation coordinate, with same method all of alignment of the second row alignment mark 512 is calculated The compensation coordinate of labelling.

Step 8：The control system according to the compensation coordinate that calculates calculate the substrate 5 with it is described The relative position relation of work stage 4, and by step one calculate the mask stage 3 with The relative position relation of the work stage 4 calculates the phase of the mask plate 2 and the substrate 5 To position relationship, then the control system is relative with the substrate 5 by the mask plate 2 Position relationship travelling workpiece platform 4 or mask stage 3 so that work stage 4 is produced with mask stage 3 Relative motion, until showing at least one alignment mark group in the control system, and shows Go out substrate 5 to be aligned with the focal plane of mask plate 2, then position alignment is aligned while complete with focal plane, Alignment actions terminate；

Step 9：When being exposed action, the scan exposure program opened in the control system is clicked on, Scan exposure starts, and while the movement work stage 4 and the mask stage 3, are moving During keep the aligned relationship that the substrate 5 formed with the mask plate 2 in step 7, Until exposure actions are completed；

Step 10：After the completion of the first exposure area 510 exposes, according to step one to step 9 one by one To the second exposure area 520, the 3rd exposure area 530, that the 4th exposure area 540 is carried out is right Quasi- action and exposure actions, the so far exposure of whole substrate 5 is completed.

Embodiment two

Refer to Figure 12, the present embodiment is with the difference of embodiment one, diaphragm 840 with Shutter 880 is provided between second light fixture 860, when shutter 880 is opened, the diaphragm Light hole 841 and slot set 842 then thang-kng on 840, when shutter 880 is closed, light hole 841 with the then not thang-kng of slot set 842, control light by controlling the opening time of shutter 880 The thang-kng time of door screen 840.

Embodiment three

Figure 13 is refer to, the present embodiment is the lighting source 1 with the difference of embodiment one It is that, with two waveband Halogen light or two waveband LED, the two waveband of lighting source 1 refers to bag Second band of the suitable position to the first band of locating tab assembly with suitable focal plane to locating tab assembly is included, and And annular filter wave plate 890 is provided between the diaphragm 840 and second light fixture 860, The zone line of annular filter wave plate 890 can pass through first band, and outer peripheral areas can be through the Two wave bands, so separate position alignment measurement to the light wave of locating tab assembly so that position with focal plane To locating tab assembly and focal plane to locating tab assembly respectively using each suitable light, so as to improve measurement alignment Degree of accuracy.

The present invention is described to above-described embodiment, but the present invention is not limited only to above-described embodiment. Obviously those skilled in the art can carry out various changes and modification without deviating from this to invention The spirit and scope of invention.So, if these modifications of the present invention and modification belong to the present invention Within the scope of claim and its equivalent technologies, then the present invention be also intended to include these change and Including modification.

Claims (21)

1. a kind of projection aligner, includes successively：

One lighting source；

One lamp optical system；

Mask stage, for carrying mask plate；

Projection objective group；

Work stage, for carrying a substrate, during scan exposure, the lighting source is sent out The light beam penetrated, through the lamp optical system, is irradiated on the mask plate, and will arrange In the pattern of the mask plate, through the projection objective, it is transferred on the substrate；

And the control system being connected with mask stage circuit, it is characterised in that

The projection aligner also includes alignment focal plane measuring system, is arranged on the mask stage And the work stage between, during crossing Cheng Qian or scan exposure in the scan exposure, While carrying out the mask plate and the substrate to locating tab assembly, the focal plane of the substrate is carried out Measurement.

2. projection aligner as claimed in claim 1, it is characterised in that the substrate is drawn It is divided into several exposure areas, the alignment focal plane is designed with each described exposure area and is surveyed Amount system and the projection objective group.

3. projection aligner as claimed in claim 1, it is characterised in that the alignment is burnt Planar survey system is connected with the control system circuit, if the alignment focal plane measuring system includes Dry alignment focal plane measuring unit, each described alignment focal plane measuring unit includes successively face battle array phase Machine, the first image-forming assembly, Amici prism and the second image-forming assembly, also successively including the first photograph Bright component, diaphragm and the second light fixture, first light fixture and the Amici prism light Road connects, and second light fixture is connected with the lighting source light path.

4. projection aligner as claimed in claim 3, it is characterised in that in the diaphragm The heart arrange light hole, the light hole surrounding arrange four slits, four slits with regard to The diaphragm center is in a center of symmetry, and four shape of slit are circular or square.

5. projection aligner as claimed in claim 4, it is characterised in that the diaphragm is Four slits are with the light hole apart from adjustable structure.

6. projection aligner as claimed in claim 3, it is characterised in that in the diaphragm Shutter is provided between second light fixture.

7. projection aligner as claimed in claim 6, it is characterised in that the illumination light Source is with two waveband Halogen light or two waveband LED, and in the diaphragm and described Annular filter wave plate is provided between two light fixtures.

8. projection aligner as claimed in claim 1, it is characterised in that the projection thing Microscope group is provided with several projection objectives, and the projection objective group is provided with public focal plane.

9. projection aligner as claimed in claim 1, it is characterised in that the illumination light Source is single-range Halogen light or single-range LED, and the lighting source has avoids light The photosensitive optical band of photoresist.

10. projection aligner as claimed in claim 1, it is characterised in that the substrate Material is glass or silica-base material.

11. projection aligners as claimed in claim 1, it is characterised in that the substrate Upper surface is provided with alignment mark, and the alignment mark number is two or more, the mask plate table Face is provided with mask alignment mark, and the mask alignment mark number is two or more.

12. projection aligners as claimed in claim 11, it is characterised in that cover when described When film version is aligned with the substrate position, in each described exposure area, the control system On at least show an alignment mark group, the alignment mark group is an alignment mark The image overlapped with a mask alignment mark center.

A kind of 13. exposure methods, including alignment actions and exposure actions, it is characterised in that Alignment focal plane measuring system is set in each exposure area, when alignment actions are carried out, is passed through Travelling workpiece platform records each described alignment focal plane measuring unit so as to drive the movement of datum plate The radius change of interior hot spot circle, calculates the work under each described alignment focal plane measuring unit Part platform at an arbitrary position when relative to projection objective group public focal plane vertical offset and The inclined light shaft that the work stage goes up at an arbitrary position, the then work stage on optional position Inclined light shaft and on the position vertical shift of the work stage relative to the public focal plane The product of amount is the compensation dosage of the alignment mark on each described datum plate, and each is aligned The coordinate of labelling is compensated, and the compensation coordinate of each alignment mark, Ran Houtong are obtained after compensation The compensation coordinate for crossing each alignment mark calculates presently described substrate with the mask plate Position relationship, the movement work stage so that the substrate is aligned with the mask plate, i.e., Action can be exposed.

14. exposure methods as described in claim 13, it is characterised in that the party Method is comprised the following steps：

Step one：When carrying out alignment actions, lighting source is opened, arbitrarily select an exposure area to make For the first exposure area, the work stage is moved by first exposure area by control system It is moved horizontally in the field range of the alignment focal plane measuring system, calculating now carries institute State the mask stage of mask plate and the relative position relation of the work stage；

Step 2：The work stage is moved horizontally by the control system, by datum plate movement To the alignment focal plane measuring system field range, in each alignment focal plane measuring unit Interior, the light that the lighting source sends sequentially passes through the in the alignment focal plane measuring system Two light fixtures, diaphragm, the first light fixture, Amici prism, the second image-forming assembly reach institute State and formed on substrate the reflected beams, the reflected beams sequentially pass through second image-forming assembly, The Amici prism, the first image-forming assembly, are finally imaged to the alignment focal plane measuring system Area array cameras on, through the diaphragm four slits light then on the area array cameras Form four hot spots, using with four spot centers all equal points of distance as the center of circle, with The distance of any one of spot center is hot spot circle as the circle that radius is formed；

Step 3：The work stage is vertically moved by the control system so that the datum plate Upper surface is located at the public focal plane of the projection objective group, then now each described alignment focal plane is surveyed Hot spot circle in amount unit is standard hot spot circle, and the control system is recorded and preserves described Standard hot spot circle half in the position coordinateses of work stage and each described alignment focal plane measuring unit Footpath r₀；

Step 4：The work stage is arbitrarily vertically moved by the control system, record is mobile every time The position coordinateses of Shi Suoshu work stages are directed at the hot spot in focal plane measuring unit with each described Round radius, the calculating work stage vertically moves position coordinateses change and Jiao is directed at each described Then the relation of the hot spot radius of circle change calculates each described alignment in interface measurement unit Under focal plane measuring unit the work stage at an arbitrary position when relative to the public focal plane hang down Straight side-play amount；

Step 5：The work stage is arbitrarily vertically moved by control system, the control system according to The coordinate position of the work stage calculates each described alignment focal plane measurement list when mobile every time The inclined light shaft expression formula that light path is present in first, then the control system is by the inclined light shaft Inclined light shaft when expression formula calculates the work stage at an arbitrary position；

Step 6：The work stage is moved horizontally by the control system, by first exposure region All described alignment mark in domain is moved in the field range of the alignment focal plane measuring system, And the horizontal position coordinate of all alignment marks is obtained as original coordinate；

Step 7：According to step 4, the control system calculate each described alignment mark relative to The vertical offset of the public focal plane, according to step 5, calculates each described alignment mark Inclined light shaft, then the vertical shift of the control system according to each alignment mark Amount and the inclined light shaft are compensated to original coordinate, the horizontal position coordinate after compensation To compensate coordinate；

Step 8：The control system is according to the compensation coordinate of the alignment mark is calculated The relative position relation of substrate and the work stage, and by covering described in calculating in step one Film platform calculates the mask plate with the substrate with the relative position relation of the work stage Relative position relation, the then relative position that the control system passes through the mask plate and the substrate Put relation and move the work stage or the mask stage, until showing in the control system Alignment mark group described at least one, and while show that focal plane is aligned, then alignment actions are complete Into；

Step 9：When being exposed action, the scan exposure program opened in the control system is clicked on, Scan exposure starts, and while the movement work stage and the mask stage, in moving process The middle aligned relationship for keeping the substrate to be formed in step 7 with the mask plate, until exposure Action is completed；

Step 10：After the completion of the exposure of first exposure area, according to step one to step 9 one by one Alignment actions and exposure actions are carried out to exposure area remaining described.

15. exposure methods as described in claim 14, it is characterised in that step 2 Described in four spot centers horizontal coordinate be respectively (xa, ya), (xb, yb), (xc, yc), (xd, yd), Then the computing formula of the horizontal coordinate (x_ce, y_ce) of the round heart of the hot spot is

$x\_ce=\frac{xa+xb+xc+xd}{4},y\_ce=\frac{ya+yb+yc+yd}{4},$ The radius that then hot spot is justified

$\begin{array}{c}r=\frac{1}{4}(\sqrt{{(\mathrm{xa}-x\_\mathrm{ce})}^2+{(\mathrm{ya}-y\_\mathrm{ce})}^2}+\sqrt{{(\mathrm{xb}-x\_\mathrm{ce})}^2+{(\mathrm{yb}-y\_\mathrm{ce})}^2}\\ +\sqrt{{(\mathrm{xc}-x\_\mathrm{ce})}^2+{(\mathrm{yc}-y\_\mathrm{ce})}^2}+\sqrt{{(\mathrm{xd}-x\_\mathrm{ce})}^2+{(\mathrm{yd}-y\_\mathrm{ce})}^2})\end{array}$

16. exposure methods as described in claim 15, it is characterised in that described four The computational methods of individual spot center are the centroid method based on gradation of image or based on pattern edge Geometrical center method.

17. exposure methods as described in claim 14, it is characterised in that step 4 Described in work stage vertically move position coordinateses change focal plane measuring unit is directed at each described The relation of the interior hot spot radius of circle change is that focal plane corrects machine constantIt is then described to control system The focal plane correction machine constant united according to each alignment focal plane measuring unitWith institute State standard hot spot radius of circle r₀Calculate the workpiece under each described alignment focal plane measuring unit Platform at an arbitrary position when relative to the public focal plane vertical offset.

18. exposure methods as described in claim 17, it is characterised in that step 4 In each it is described alignment focal plane measuring unit under the work stage at an arbitrary position when relative to institute State the vertical offset of public focal plane

19. exposure methods as described in claim 18, it is characterised in that in step Four vertical position to the coordinates for arbitrarily moving the work stage are (x1, y1, z1), continue arbitrarily mobile The vertical position of the work stage to vertical coordinate is (x2, y2, z2), and the focal plane corrects machine constantWherein r1 is the radius of (x1, y1, z1) the corresponding hot spot circle, and r2 is The radius of (x2, y2, z2) corresponding described hot spot circle.

20. exposure methods as described in claim 19, it is characterised in that step 5 In each it is described alignment focal plane measuring unit inclined light shaft be (θ_Ry,θ_Rx), and $\begin{array}{cc}{\mathrm{\θ}}_{Rx}=\frac{y2-y1}{z2-z1},& {\mathrm{\θ}}_{Ry}=\frac{x2-x1}{z2-z1}\end{array}.$

21. exposure methods as described in claim 20, it is characterised in that step 5 In described original coordinate be (x, y), the compensation coordinate in step 6 be (X, Y), wherein X=x+ Δs Z × θ_Ry, Y=y+ Δs Z × θ_Rx。