CN102096349B - System for automatic dual-grating alignment in proximity nanometer lithography - Google Patents
System for automatic dual-grating alignment in proximity nanometer lithography Download PDFInfo
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- CN102096349B CN102096349B CN2010106238918A CN201010623891A CN102096349B CN 102096349 B CN102096349 B CN 102096349B CN 2010106238918 A CN2010106238918 A CN 2010106238918A CN 201010623891 A CN201010623891 A CN 201010623891A CN 102096349 B CN102096349 B CN 102096349B
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Abstract
The invention relates to a system for automatic dual-grating alignment in proximity nanometer lithography, comprising a light path part, an image processing part and a circuit control part, wherein the light path part comprises a laser source, a lens group, a mask, a silicon wafer, a mask grating, a silicon wafer grating, a beam splitter, an objective lens and a CCD (charge coupled device) image detector; lasers pass through the lens group and then forms uniform and collimated parallel lights which are subjected to diffraction for a plurality of times through the silicon wafer grating and the mask grating, and the two gratings have approaching periods and are superposed with a certain gap; certain two same-level diffraction light beams from the two gratings are subjected to interference superposition, Moire interference fringes with the period of being amplified compared with that of the original grating are formed on the surface of the silicon wafer grating, and then the Moire interference fringes are imaged on the CCD image detector by virtue of the objective lens. By processing images, phase difference of two groups of Moire interference fringes can be extracted, further the relative displacement of the mask and the silicon wafer can be calculated, and the silicon wafer is controlled to move by the circuit control part so as to realize complete alignment of the silicon wafer and the mask. By utilizing the system provided by the invention, real-time alignment can be achieved, the accuracy is high, and the automation of alignment can be realized.
Description
Technical field
The present invention relates to a kind of Automatic Alignment System in the photoetching,, belong to technical field of micro and nano fabrication especially near formula nano-photoetching double grating Automatic Alignment System.
Background technology
Along with the research and development of highly integrated circuit and related device, the characteristic dimension of IC is more and more little, has obtained significant progress with the high resolution micro-nano process technology that is lithographically representative.With its characteristic such as simple to operate, with low cost, become one of mainstream technology of future generation, near the contact type nanometer manufacturing process like nano impression, array of zone plates imaging and photo-etching and X-ray lithography.Along with the raising of photolithography resolution, the mask silicon chip is aimed to become influences one of device feature size accuracy factors.
Existing alignment methods can be based on several kinds of geometric scheme mark, zone plate and grating markers etc. substantially.Wherein, be directly the geometric scheme on mask and the silicon chip to be imaged onto on the detector based on the alignment methods of geometric scheme mark, extract the profile or the center of two geometric schemes again through Flame Image Process, calculate the two relative coordinate and aim at realizing.Its operation is simple with the alignment mark making, but precision is relatively low, is used for the manual-alignment in the early stage low resolution photoetching more.All reflect the relative displacement of mask silicon chip with the light intensity signal size based on the linear wave strap with based on the alignment methods of diffraction grating mark; Can reach higher precision; But it can't avoid the disturbing influence of multiple factors such as the variation of mask silicon chip gap, mark symmetry, photoresist coating, etching technics to light intensity signal; And need to handle through complicated circuitry, cost is also higher, and automaticity is lower.
Summary of the invention
The technical issues that need to address of the present invention are: the deficiency that overcomes prior art; Provide a kind of and be used near formula nano-photoetching double grating Automatic Alignment System, this system is not vulnerable to the influence of silicon chip technology, and alignment precision is higher; And operation is simple, and automaticity is high.
Technical solution of the present invention: a kind of being used for is made up of light path part, image processing section and circuit control section near formula nano-photoetching double grating Automatic Alignment System, wherein "
Said light path part comprises: LASER Light Source, lens combination, mask, silicon chip, be positioned at mask grating on the mask, be positioned at silicon chip grating, spectroscope, object lens, ccd image detector and image processing section and circuit control section on the silicon chip; LASER Light Source is through forming the directional light of even collimation after the lens combination, through silicon chip grating on the silicon chip and the mask grating on the mask, the cycle of these two gratings is approaching behind this directional light process spectroscope; And it is overlapping with certain interval; Repeatedly diffraction takes place thus, and certain the two bundle diffraction light at the same level that comes from two gratings interferes stack, forms the Moire fringe that the cycle is exaggerated with respect to former grating on the surface of silicon chip grating; See through spectroscope again; Be imaged on the ccd image detector through object lens then,, calculate the relative displacement between mask and the silicon chip through image processing section being handled the phase differential that extracts two groups of Moire fringes; Move through circuit control section control silicon chip again, silicon chip is aimed at mask fully;
Said image processing section comprises that IMAQ, image filtering, phase extraction, phase difference calculating and side-play amount calculate five parts and form; Wherein IMAQ is to gather and convert to digital picture through CCD; Then separately with whole stripe pattern top and the bottom; Respectively the top and the bottom image is carried out two-dimensional Fourier transform again,, can calculate the phase place of top and the bottom image respectively through carrying out bandpass filtering at frequency domain; Two-part phase place asks difference can get phase difference φ about in the image, calculates the side-play amount of mask and silicon chip through formula (1);
P wherein
1With P
2Be two groups of adjacent mask gratings (5) and mask grating (6) cycle, Δ φ is the phase differential that obtains in the Flame Image Process, and Δ x is the silicon chip (3) asked and the side-play amount of mask (4);
Said circuit control section comprises side-play amount contrast judgement, reads the silicon chip position, judges moving direction and motor-driven part; At first obtain the side-play amount of image processing section, absolute value and a certain preset threshold to said side-play amount compares again, if less than threshold value then withdraw from; Show that the mask silicon chip aims at fully,, then show the misalignment of mask silicon chip if greater than threshold value; Confirm the position of silicon chip and mask earlier; Confirm the silicon chip moving direction again, through the motor-driven silicon chip, make silicon chip move the distance of side-play amount at last;
Feedback procedure promptly through the opticator imaging, through the CCD images acquired, draws side-play amount through image processing section; The circuit control section is judged; Drive motor moves silicon chip afterwards, passes through optical imagery again, and images acquired so circulates; Withdraw from less than preset threshold up to side-play amount, realized full automation.
Said two groups of adjacent mask gratings (5) and mask grating (6) are P by the cycle respectively
1With P
2, P
2With P
1Two gratings constitute up and down.
The threshold value setting of said circuit control section should be nanometer scale, and scope is that 1nm is to 10nm.
The present invention's beneficial effect compared with prior art is:
(1) the present invention directly carries out mask and silicon chip aligning according to spatial phase feature, can avoid influencing the influence of silicon chip technological factors such as photoresist to aiming at of light intensity, has Technological adaptability and antijamming capability preferably, reaches high precision.
(2) the present invention forms FEEDBACK CONTROL through opticator, Flame Image Process, circuit control section; Promptly show in the phase change of striped through of the relative displacement of double grating space phase interference imaging principle with the mask silicon chip; Obtain bar graph through the CCD imaging system; Obtain phase place and then calculate side-play amount through the Flame Image Process phase extraction method again, again through each track control system of control algolithm feedback, the completion whole silicon wafer is aimed at mask.This invention is not vulnerable to the influence of silicon chip technology, and alignment precision is higher, and operation is simple, and automaticity is high.
(3) the present invention, can directly aim at again through simple Flame Image Process through the double grating mark diffraction imaging of design, and it is low to have a cost, the production efficiency advantages of higher.
Description of drawings
Fig. 1 is a light channel structure synoptic diagram of the present invention;
Fig. 2 a is a mask grating marker schematic layout pattern; Fig. 2 b is a silicon chip grating marker schematic layout pattern;
Fig. 3 a is mask grating and silicon chip grating misalignment synoptic diagram; Fig. 3 b is that the mask grating is aimed at synoptic diagram fully with the silicon chip grating;
Fig. 4 realizes block diagram for image processing section of the present invention;
Fig. 5 realizes block diagram for circuit control section of the present invention;
Fig. 6 is the process of feedback figure of total system of the present invention.
Embodiment
As shown in Figure 1, light path part of the present invention is made up of LASER Light Source 1, lens combination 2, mask 3, silicon chip 4, mask grating 5, silicon chip grating 6, spectroscope 7, object lens 8, ccd image detector 9.LASER Light Source 1 forms the directional light of even collimation through lens combination 2 backs; Through the mask grating 5 on silicon chip grating on the silicon chip 46 and the mask 3; The cycle of these two gratings is approaching, and is that 100nm is overlapping to 200 μ m with the gap length, and repeatedly diffraction takes place thus; Certain the two bundle diffraction light at the same level that comes from two gratings interferes stack; Form the Moire fringe that the cycle is exaggerated with respect to former grating on the surface of silicon chip grating, see through spectroscope 7 again, then through enlargement ratio be 8 * object lens 8 be imaged on the ccd image detector 9.When mask 3 and silicon chip 4 were in alignment, the PHASE DISTRIBUTION of two groups of stripeds was consistent, and frequency equates; When having relative displacement between mask 3 and the silicon chip 4, the PHASE DISTRIBUTION of two groups of stripeds changes, no longer consistent.
Like Fig. 2 a, shown in the 2b, two groups of gratings adopt layouts as shown in Figure 2 on mask 3 and the silicon chip 4, and mask grating 5, silicon chip grating 6 are respectively P by the cycle respectively
1With P
2, P
2With P
1Two gratings constitute P in the embodiment of the invention wherein up and down
1=10.0 μ m, P
2=11 μ m.When the reflection of mask 3 through silicon chip 4 surface, grating 5+meet, promptly produce two groups of interference fringes on 6 on the 1 order diffraction light mark grating on the right.Fig. 3 is two groups of interference fringes according to mark emulation shown in Figure 2, when silicon chip and mask when having certain relative displacement, its striped distributes like Fig. 3 a, at this moment two groups of fringe spatial frequency are inconsistent up and down, and two groups of stripeds are easy to distinguished; When the relative displacement of silicon chip and mask is eliminated, two groups of striped frequencies are equal fully, and like 3b, at this moment, mask 3 is aimed at completion with silicon chip 4, and reaches perfect condition.
As shown in Figure 4; The image processing section of this embodiment is made up of five parts; At first image is gathered and is converted into digital picture through the ccd image detector, the striped top and the bottom are separately carried out two-dimensional Fourier transform to two parts image respectively then and are got into frequency domain in digital picture; Through the bandpass filtering filtering noise and extract the effective frequency part; Calculate the phase place of two parts striped up and down respectively, so can obtain the phase differential of top and the bottom, calculate the side-play amount of silicon chip and mask at last through formula (1).
As shown in Figure 5, the automatically controlled part of this embodiment at first obtains the offset x of mask and silicon chip from image processing section.The absolute value and a certain preset threshold t that judge side-play amount again compare; It is 5nm that this embodiment is selected threshold value, if less than threshold value then withdraw from, if greater than threshold value; Then confirm the position of silicon chip and mask earlier; Confirm the silicon chip moving direction again, through the motor-driven silicon chip, make silicon chip move the distance of side-play amount at last.
As shown in Figure 6, the whole process of feedback of this embodiment, light path part replaces with silicon chip grating and mask grating; Two gratings produce interference fringe and obtain stripe pattern through CCD, calculate the side-play amount of mask silicon chip again through image processing section, send into the circuit control section; Compare, if misalignment is then fed back through the motor-driven silicon chip and moved; So accomplish an alignment procedures; Get into second and take turns the imaging link, less than preset threshold, whole process has realized full automation until side-play amount.
The present invention does not set forth part in detail and belongs to techniques well known.
Claims (3)
1. one kind is used for it is characterized in that being made up of light path part, image processing section and circuit control section near formula nano-photoetching double grating Automatic Alignment System, wherein:
Said light path part comprises: LASER Light Source (1), lens combination (2), mask (3), silicon chip (4), be positioned at mask grating (5) on the mask, be positioned at silicon chip grating (6), spectroscope (7), object lens (8), ccd image detector (9) and image processing section (10) and circuit control section (11) on the silicon chip; Form the directional light of even collimation after LASER Light Source (1) the process lens combination (2), through silicon chip grating (6) on the silicon chip (4) and the mask grating (5) on the mask (3), the cycle of these two gratings is approaching through spectroscope (7) back for this directional light; And it is overlapping with certain interval; Repeatedly diffraction takes place thus, and certain the two bundle diffraction light at the same level that comes from two gratings interferes stack, forms the Moire fringe that the cycle is exaggerated with respect to former grating on the surface of silicon chip grating; See through spectroscope (7) again; Pass through object lens (8) then and image on the ccd image detector (9),, calculate the relative displacement between mask and the silicon chip through image processing section (10) being handled the phase differential that extracts two groups of Moire fringes; Move through circuit control section (11) control silicon chip (4) again, silicon chip (4) is aimed at mask (3) fully;
Said image processing section comprises that IMAQ, image filtering, phase extraction, phase difference calculating and side-play amount calculate five parts and form; Wherein IMAQ is to gather and convert to digital picture through CCD; Then separately with whole stripe pattern top and the bottom; Respectively the top and the bottom image is carried out two-dimensional Fourier transform again,, can calculate the phase place of top and the bottom image respectively through carrying out bandpass filtering at frequency domain; Two-part phase place asks difference can get phase difference φ about in the image, calculates the side-play amount of mask and silicon chip through formula (1);
P wherein
1With P
2Be two groups of adjacent mask gratings (5) and silicon chip grating (6) cycle, Δ φ is the phase differential that obtains in the Flame Image Process, and Δ x is the silicon chip (3) asked and the side-play amount of mask (4);
Said circuit control section comprises side-play amount contrast judgement, reads the silicon chip position, judges moving direction and motor-driven part; At first obtain the side-play amount of image processing section, absolute value and a certain preset threshold to said side-play amount compares again, if less than threshold value then withdraw from; Show that the mask silicon chip aims at fully,, then show the misalignment of mask silicon chip if greater than threshold value; Confirm the position of silicon chip and mask earlier; Confirm the silicon chip moving direction again, through the motor-driven silicon chip, make silicon chip move the distance of side-play amount at last;
Feedback procedure promptly through the opticator imaging, through the CCD images acquired, draws side-play amount through image processing section; The circuit control section is judged; Drive motor moves silicon chip afterwards, passes through optical imagery again, and images acquired so circulates; Withdraw from less than preset threshold up to side-play amount, realized full automation.
2. according to claim 1 being used for is characterized in that near formula nano-photoetching double grating Automatic Alignment System: said two groups of adjacent mask gratings (5) and silicon chip grating (6) are P by the cycle respectively
1With P
2, P
2With P
1Two gratings constitute up and down.
3. according to claim 1 being used near formula nano-photoetching double grating Automatic Alignment System, it is characterized in that: the threshold value setting of said circuit control section should be nanometer scale, and scope arrives 10nm at 1nm.
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Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103135371B (en) * | 2011-12-02 | 2015-02-11 | 上海微电子装备有限公司 | Small light spot off-axis aligning system based on beam splitting deflection structure |
| CN103792794B (en) * | 2012-11-02 | 2016-02-03 | 上海微电子装备有限公司 | A kind of Proximity stepper |
| CN104133350B (en) * | 2013-05-03 | 2017-02-08 | 上海微电子装备有限公司 | Aligning system and aligning method for photolithographic device |
| US10420521B2 (en) | 2014-08-05 | 2019-09-24 | Koninklijke Philips N.V. | Grating device for an X-ray imaging device |
| CN104536273B (en) * | 2015-01-04 | 2017-02-22 | 中国科学院光电技术研究所 | Two-dimensional grating automatic aligning system for proximity type nano lithography |
| CN105988309B (en) * | 2015-02-26 | 2019-01-18 | 上海微电子装备（集团）股份有限公司 | A kind of alignment device and alignment methods for lithographic equipment |
| CN104614955B (en) * | 2015-03-06 | 2017-01-11 | 中国科学院光电技术研究所 | Compound raster nanometer photoetching automatic aligning system |
| CN106017308B (en) * | 2016-07-22 | 2019-01-04 | 清华大学 | A kind of six degree of freedom interferometer measuration system and method |
| CN111427237B (en) * | 2019-01-10 | 2021-07-23 | 苏州苏大维格科技集团股份有限公司 | Large-area nano photoetching system and method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2352975Y (en) * | 1998-09-03 | 1999-12-08 | 中国科学院光电技术研究所 | Optical grating diffraction coaxial alignment device of submillimeter photoetching machine |
| CN2421670Y (en) * | 1999-11-30 | 2001-02-28 | 中国科学院光电技术研究所 | Optical pre-alighment apparatus for submicron photoetching device |
| CN101581889A (en) * | 2009-01-15 | 2009-11-18 | 上海微电子装备有限公司 | Alignment mark, alignment system and alignment method for photomask processor |
| CN101681121A (en) * | 2007-12-14 | 2010-03-24 | 株式会社尼康 | Exposure apparatus, exposure method, and device manufacturing method |
-
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- 2010-12-31 CN CN2010106238918A patent/CN102096349B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2352975Y (en) * | 1998-09-03 | 1999-12-08 | 中国科学院光电技术研究所 | Optical grating diffraction coaxial alignment device of submillimeter photoetching machine |
| CN2421670Y (en) * | 1999-11-30 | 2001-02-28 | 中国科学院光电技术研究所 | Optical pre-alighment apparatus for submicron photoetching device |
| CN101681121A (en) * | 2007-12-14 | 2010-03-24 | 株式会社尼康 | Exposure apparatus, exposure method, and device manufacturing method |
| CN101581889A (en) * | 2009-01-15 | 2009-11-18 | 上海微电子装备有限公司 | Alignment mark, alignment system and alignment method for photomask processor |
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