CN103376672A - Aligning signal processing system for photolithographic equipment - Google Patents
Aligning signal processing system for photolithographic equipment Download PDFInfo
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- CN103376672A CN103376672A CN2012101179170A CN201210117917A CN103376672A CN 103376672 A CN103376672 A CN 103376672A CN 2012101179170 A CN2012101179170 A CN 2012101179170A CN 201210117917 A CN201210117917 A CN 201210117917A CN 103376672 A CN103376672 A CN 103376672A
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Abstract
The invention discloses an aligning signal processing system for photolithographic equipment. The aligning signal processing system comprises a signal acquisition module, a level separating module and a signal processing module, wherein the signal acquisition module is used for acquiring optical signals in all levels and converting the optical signals into optical intensity data; the level separating module is used for performing level separation on scattered optical intensity data and extracting optical intensity data in each level; the signal processing module is used for obtaining aligning positions according to the optical intensity data in each level.
Description
Technical field
The present invention relates to a kind of integrated circuit equipment manufacturing field, relate in particular to a kind of registration signal disposal system for lithographic equipment.
Background technology
In the semiconducter IC ic manufacturing process, complete chip need to just can complete through photolithographic exposure repeatedly usually.Except the photoetching first time, the photoetching of all the other levels figure that stays that all figure of this level and former level will be exposed before exposure is accurately located, and between each layer pattern of guarantee correct relative position is arranged like this, i.e. alignment precision.Generally, alignment precision is 1/3～1/5 of litho machine resolution index, and for the litho machine of 100 nanometers, the alignment precision index request is less than 35nm.Alignment precision is one of the key technical indexes of projection mask aligner, and the alignment precision between the mask and wafer is the key factor that affects alignment precision.When characteristic dimension CD requires more hour, the requirement of alignment precision and the requirement of consequent alignment precision are become stricter, such as the CD dimensional requirement 10nm of 90nm or less alignment precision.
The mode to adopting mask (coaxial) aligning+silicon chip (from axle) to aim between the mask and wafer namely is labeled as bridge with the work stage datum plate, sets up the position relationship between mask mark and the silicon chip mark, as shown in Figure 1.The basic process of aiming at is: be mask alignment system by the 9(of coaxial alignment system at first), realize mask mark 3 and aiming between the datum plate mark 7 on the sports platform 5, then utilize the 10(of off-axis alignment system silicon chip alignment system), finish aiming between silicon chip alignment mark 6 and the work stage datum plate mark 7 (realizing by twice aligning), and then indirectly realize aiming between silicon chip alignment mark 6 and the mask alignment mark 3, set up the position coordinates relation between the two.
Patent EP1148390, US7564534 and CN03133004.5 have provided a kind of self-reference and have interfered alignment system, as shown in Figure 2.This alignment system is by picture whirligig 22, realize the division of alignment mark point diffraction wave surface, and the relative 180 ° overlapping interference of rotation in two corrugateds after the division, then utilize light intensity signal detector 27, registration signal after the pupil plane place surveys interference is by the aligned position of signal analyzer 28 definite marks 24.It is 180 ° of Rotational Symmetries that this alignment system requires alignment mark.Are the most crucial devices of this alignment system as whirligig 22, are used for division and the rotation of marker image.In this invention, realize by Self-referencing interferometer.In addition, because the diverse location place on each illuminating bundle space, interference point source on the interference wave surface, so this alignment system requires lighting source to possess strict spatial coherence.
Summary of the invention
In order to overcome the defective that exists in the prior art, the invention provides a kind of registration signal disposal system for lithographic equipment, this registration signal disposal system especially is adapted to self-reference and interferes alignment system.
In order to realize the foregoing invention purpose, the invention provides a kind of registration signal disposal system for lithographic equipment, comprise: signal acquisition module, level time separation module and signal processing module, the optical signalling that the whole levels of this signal acquisition module collection are inferior also is converted into light intensity data, this grade time separation module is used for discrete light intensity data is carried out level time separation, extract light intensity data at different levels times, this signal processing module obtains aligned position according to these at different levels light intensity datas.
Further, this signal acquisition module comprises: a photoelectric conversion unit is used for the optical signalling of optical fiber input is converted to electrical signal and amplification; One demodulating unit is used for electrical signal is carried out demodulation, output simulation registration signal; One A/D sampling unit is used for the discrete sampling of simulation registration signal is obtained light intensity data; One position sampling unit is used for being sampled in the position of work stage, obtains the work stage position data.
Further, this signal processing module comprises: a Fitting Calculation unit, be used for respectively at different levels light intensity datas that obtain being carried out process of fitting treatment with the work stage position data, the fitting parameter of acquisition model, at different levels light intensity datas that are somebody's turn to do share the work stage position data; One aims at the displace analysis unit, is used for according to the process of fitting treatment result, asks for aligned position.
Further, this level time separation module is a firmware module.This level time separation module adopts band-pass filtering method, wavelet analysis method or Fourier transformation method.This bandpass filter method adopts following bandpass filter to realize:
In the formula, M is molecule polynomial expression exponent number,
(
) being minute each rank coefficient of submultinomial, N is denominator polynomial expression exponent number,
(
) be each rank coefficient of denominator polynomial expression, N has also determined the exponent number of wave filter, and z is operator, and H (z) is called N rank iir filter function.
Further, this position sampling unit and A/D sampling unit keep sample-synchronous by synchronizing signal.
The present invention is directed to self-reference and interfere alignment system, all level time signals need hardware integrated circuit board or software by the rear end by the optical fiber output that combines, and extract and are included in wherein each level time registration signal, carry out aligned position calculating.The corresponding scheme of the present invention is preferably carried out the inferior extraction of signal level in software, to obtain better dirigibility, it is also more convenient to implement.
Description of drawings
Can be by following detailed Description Of The Invention and appended graphic being further understood about the advantages and spirit of the present invention.
Fig. 1 is the aligning schematic flow sheet from axle coaxial alignment system that is used for lithographic equipment in the prior art;
Fig. 2 is that employed self-reference is interfered alignment system in the prior art;
Fig. 3 is the structural representation of registration signal disposal system involved in the present invention;
Fig. 4 is the signal form figure after each processing links involved in the present invention;
Fig. 5 is the amplitude-frequency response characteristic synoptic diagram of bandpass filter.
Embodiment
Below, describe in detail according to a preferred embodiment of the invention by reference to the accompanying drawings.For convenience of description and highlight the present invention, omitted existing associated components in the prior art in the accompanying drawing, and will omit the description to these well-known components.
The object of the invention is to provide a kind of self-reference registration signal disposal system.This signal processing system can be processed the registration signal that obtains, and isolates each order of diffraction time signal, then fully utilizes signal at different levels times, obtains the accurate aligned position of mark.
The present invention includes following signal processing unit:
A/D sampling unit 303 is used for the discrete sampling of simulation registration signal is obtained discrete aligning light intensity data.The A/D sampling unit is controlled by synchronous triggering signal, carries out synchronously with assurance and position sampling.
Level time separative element 304, level is inferior separates for discrete registration signal is carried out, and extracts light intensity data at different levels times.Level time separative element can be realized at the FPGA of hardware integrated circuit board Program, also can realize at the DSP Program.In addition, grade time separative element also can carry out before the A/D sampling, namely after demodulation, by hardware the simulation registration signal was carried out level time separation according to frequency.Preferably, inferior being separated in the discrete signal of level carried out, and namely realizes in program by FPGA or DSP, to obtain greater flexibility.
The Fitting Calculation unit 306 is used for obtaining light intensity data at different levels times, and position data is carried out process of fitting treatment, obtains the fitting parameter of each model.
Aligned position is found the solution unit 307, is used for the model of at different levels signals after the match is calculated, and fully utilizes at different levels times signal, calculates the aligned position of mark.
Fig. 4 has provided through after each processing links, the form of light intensity signal.Wherein, level time separation is a key link.When level time is separated in when carrying out in the discrete signal, can adopt Fourier transformation method, digital filter disposal route, adopt wavelet analysis method, or other signal processing method.
For example, adopt bandpass filtering to realize the decomposition of signal, can extract signal at different levels times.To time signal not at the same level, its frequency is different, and for example n level signal is
Particularly, can adopt infinite impulse response (IIR) filter function, formula is:
In the formula, M is molecule polynomial expression exponent number,
(
) being minute each rank coefficient of submultinomial, N is denominator polynomial expression exponent number,
(
) be each rank coefficient of denominator polynomial expression, N has also determined the exponent number of wave filter, and z is operator, and H (z) is called N rank iir filter function.The design of digital band-pass filter is exactly passband as required, determines the coefficient in the formula one
With
Utilize computer-implemented method, or carry out first the design of analog bandpass filtering device, then be converted into the method for digital filter, design easily the digital band-pass filter that meets the demands.Concrete method for designing can with reference to digital filter teaching material arbitrarily, be introduced as known technology herein.Accompanying drawing 5 has provided the spectral response characteristic of the digital band-pass filter that designs, and the passband of this wave filter is [100Hz, 200Hz].
Detailed disposal route about photoelectric conversion unit, demodulating unit, A/D sampling unit and position sampling unit, but list of references 1(micro-optic acquisition of signal technique of alignment, Yang Xingping, Cheng Jianrui, the electronics industry specialized equipment, 2006,140:7～12) and formerly patent CN 200810035115.9 introduces as known technology here.
The Fitting Calculation unit of signal and aligned position are found the solution the unit can adopt method described in formerly patent CN200810033263.7, CN200710045495.X, CN200710044153.6, CN200710044152.1, CN200810035115.9, CN200810040234.3, CN200910052799.8, CN200910047030.7, the CN200910194853.2,200910055927.4, introduces as known technology herein.
The peak value of finding the solution rudimentary signal that can be by lower frequency of aligned position is determined the coarse alignment position, and the peak value of senior signal is determined the fine alignment position on basis, coarse alignment position.As adopt 1 grade of signal apart from the nearest peak point of desired locations as the coarse alignment position, and near the peak point of 9 grades of nearest signals of this coarse alignment position as the fine alignment position.
Described in this instructions is preferred embodiment of the present invention, and above embodiment is only in order to illustrate technical scheme of the present invention but not limitation of the present invention.All those skilled in the art all should be within the scope of the present invention under this invention's idea by the available technical scheme of logical analysis, reasoning, or a limited experiment.
Claims (7)
1. registration signal disposal system that is used for lithographic equipment, it is characterized in that, comprise: signal acquisition module, level time separation module and signal processing module, the optical signalling that the whole levels of described signal acquisition module collection are inferior also is converted into light intensity data, level is inferior separates described level time separation module for discrete light intensity data is carried out, extract light intensity data at different levels times, described signal processing module obtains aligned position according to described at different levels light intensity datas.
2. the registration signal disposal system for lithographic equipment as claimed in claim 1 is characterized in that described signal acquisition module comprises:
One photoelectric conversion unit is used for the optical signalling of optical fiber input is converted to electrical signal and amplification;
One demodulating unit is used for electrical signal is carried out demodulation, output simulation registration signal;
One A/D sampling unit is used for the discrete sampling of simulation registration signal is obtained light intensity data;
One position sampling unit is used for being sampled in the position of work stage, obtains the work stage position data.
3. the registration signal disposal system for lithographic equipment as claimed in claim 1 is characterized in that described signal processing module comprises:
One the Fitting Calculation unit is used for respectively at different levels light intensity datas that obtain being carried out process of fitting treatment with the work stage position data, the fitting parameter of acquisition model, and described at different levels light intensity datas share the work stage position data;
One aims at the displace analysis unit, is used for according to the process of fitting treatment result, asks for aligned position.
4. the registration signal disposal system for lithographic equipment as claimed in claim 1 is characterized in that, described level time separation module is a firmware module.
5. the registration signal disposal system for lithographic equipment as claimed in claim 1 is characterized in that, described level time separation module adopts band-pass filtering method, wavelet analysis method or Fourier transformation method.
6. the registration signal disposal system for lithographic equipment as claimed in claim 5 is characterized in that, described bandpass filter method adopts following bandpass filter to realize:
In the formula, M is molecule polynomial expression exponent number,
(
) being minute each rank coefficient of submultinomial, N is denominator polynomial expression exponent number,
(
) be each rank coefficient of denominator polynomial expression, N has also determined the exponent number of wave filter, and z is operator, and H (z) is called N rank iir filter function.
7. the registration signal disposal system for lithographic equipment as claimed in claim 2 is characterized in that, described position sampling unit and A/D sampling unit keep sample-synchronous by synchronizing signal.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109946927A (en) * | 2017-12-20 | 2019-06-28 | 上海微电子装备（集团）股份有限公司 | Optical registration signal processing method, grating alignment method and to Barebone |
| CN111130615A (en) * | 2018-10-30 | 2020-05-08 | 华为技术有限公司 | APT subsystem and communication system of spacecraft |
| CN111830792A (en) * | 2019-04-18 | 2020-10-27 | 佳能株式会社 | Substrate processing apparatus, article manufacturing method, substrate processing system, management apparatus, and storage medium |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1022207A (en) * | 1996-07-08 | 1998-01-23 | Nikon Corp | Position detector |
| CN1949087A (en) * | 2006-11-03 | 2007-04-18 | 上海微电子装备有限公司 | Aligning system of photoetching apparatus and steping combined system of said aligning system thereof |
| CN101158814A (en) * | 2007-08-31 | 2008-04-09 | 上海微电子装备有限公司 | Marker for photo-etching machine aligning and aligning using the same |
| CN101487991A (en) * | 2009-03-04 | 2009-07-22 | 上海微电子装备有限公司 | Silicon slice alignment system |
| JP2011014578A (en) * | 2009-06-30 | 2011-01-20 | Kawasaki Microelectronics Inc | Method for detecting position |
| CN102314091A (en) * | 2010-07-01 | 2012-01-11 | 上海微电子装备有限公司 | Lithography machine capable of adjusting size of lighting spot of alignment system |
-
2012
- 2012-04-22 CN CN201210117917.0A patent/CN103376672B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1022207A (en) * | 1996-07-08 | 1998-01-23 | Nikon Corp | Position detector |
| CN1949087A (en) * | 2006-11-03 | 2007-04-18 | 上海微电子装备有限公司 | Aligning system of photoetching apparatus and steping combined system of said aligning system thereof |
| CN101158814A (en) * | 2007-08-31 | 2008-04-09 | 上海微电子装备有限公司 | Marker for photo-etching machine aligning and aligning using the same |
| CN101487991A (en) * | 2009-03-04 | 2009-07-22 | 上海微电子装备有限公司 | Silicon slice alignment system |
| JP2011014578A (en) * | 2009-06-30 | 2011-01-20 | Kawasaki Microelectronics Inc | Method for detecting position |
| CN102314091A (en) * | 2010-07-01 | 2012-01-11 | 上海微电子装备有限公司 | Lithography machine capable of adjusting size of lighting spot of alignment system |
Non-Patent Citations (1)
| Title |
|---|
| 李运锋 等: "用于光刻装置的多光栅标记对准系统", 《微纳电子技术》, vol. 46, no. 8, 31 August 2009 (2009-08-31), pages 494 - 497 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109946927A (en) * | 2017-12-20 | 2019-06-28 | 上海微电子装备（集团）股份有限公司 | Optical registration signal processing method, grating alignment method and to Barebone |
| CN111130615A (en) * | 2018-10-30 | 2020-05-08 | 华为技术有限公司 | APT subsystem and communication system of spacecraft |
| US11387903B2 (en) | 2018-10-30 | 2022-07-12 | Huawei Technologies Co., Ltd. | APT subsystem and spacecraft communications system |
| CN111830792A (en) * | 2019-04-18 | 2020-10-27 | 佳能株式会社 | Substrate processing apparatus, article manufacturing method, substrate processing system, management apparatus, and storage medium |
| CN111830792B (en) * | 2019-04-18 | 2024-01-02 | 佳能株式会社 | Substrate processing apparatus, article manufacturing method, substrate processing system, management apparatus, and storage medium |
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Address after: 201203 Shanghai Zhangjiang High Tech Park of Pudong New Area Zhang Road No. 1525 Patentee after: Shanghai microelectronics equipment (Group) Limited by Share Ltd Address before: 201203 Shanghai Zhangjiang High Tech Park of Pudong New Area Zhang Road No. 1525 Patentee before: Shanghai Micro Electronics Equipment Co., Ltd. |