CN102243138A - Focal plane detection device for projection lithography - Google Patents
Focal plane detection device for projection lithography Download PDFInfo
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- CN102243138A CN102243138A CN2011102246197A CN201110224619A CN102243138A CN 102243138 A CN102243138 A CN 102243138A CN 2011102246197 A CN2011102246197 A CN 2011102246197A CN 201110224619 A CN201110224619 A CN 201110224619A CN 102243138 A CN102243138 A CN 102243138A
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Abstract
The invention provides a focal plane detection device for projection lithography. The device is characterized in that: light emitted by a lighting source is irradiated to an absolute encoded grating; the light which is modulated by the encoded grating passes through a projection imaging system, and is projected and imaged to a surface to be detected through a first reflector; after being reflected by the surface to be detected, the light enters a focus detecting mark amplification system through a second reflector and is received by a detector; a height change of the surface to be detected changes an absolute encoded grating image received by the detector, the absolute encoded grating image is received by utilizing the detector, and absolute codes of a grating image corresponding to the height of the surface to be detected is extracted to complete detection on the position height of the surface to be detected. The focal plane detection device adopts the absolute encoded grating instead of the traditional grating slit, and reduces the coding cycle by increasing the number of code bits of the absolute encoded grating, so that the focal detection range can be enlarged, and the focus detection accuracy can be improved.
Description
Technical field
The present invention relates to the focusing test technology in the projection lithography system, is a kind ofly to utilize encode grating based on the optical triangulation principle, realizes the substrate high variable quantity is carried out the technology of large-range measuring.
Background technology
Projection mask aligner is one of visual plant of large scale integrated circuit production.Projection objective in the projection mask aligner is as core component, and its major function is that the figure on the mask plate is imaged onto on the object that will process by a certain percentage.Because the projection objective depth of focus is limited,, in exposure process, need to make the respective surfaces of processing object to be positioned at all the time within the object lens focal depth range for guaranteeing the exposure quality.For this reason, projection mask aligner has adopted the focusing test system that the surface elevation variable quantity of processing object is measured, and on this basis work stage is adjusted, and work surface is positioned on the projection objective focal plane all the time.
Focusing test system in the existing lithographic equipment adopts the triangle principle that the height change information of work surface is measured usually.In the measuring process, slit grating is looked like to project to work surface, utilize the slit image after CCD or other photoelectric detectors receive reflection, the slit image position that the height change of work surface will make CCD detect changes, and can obtain the high variable quantity of work surface by finding the solution slit image center information that CCD detects.Because adopt slit as position mark, the measurement range of focusing test system is limited, but height change exceeds the CCD field range, can't measure.And in the measuring process, slit image may be positioned at the CCD marginal position, in order to obtain high-quality imaging results, CCD camera lens quality is had higher requirements.
Summary of the invention
The purpose of this invention is to provide a kind of focal plane pick-up unit that is used for projection lithography based on encode grating, limited to solve the measurement range that existing lithographic equipment focusing test system exists, problems such as CCD lens imaging quality requirements height.
To achieve these goals, the focal plane pick-up unit that is used for projection lithography provided by the invention, primary structure is:
One lighting source, the illumination of sending is mapped on the specific coding grating, through the light after the absolute encode grating modulation by behind the projection imaging system by the first catoptron projection imaging to be measured on, after to be measured reflection, receive by detector after entering focusing test mark amplification system by second catoptron; To be measured height change, the specific coding grating that detector is received looks like to change, and utilizes detector to receive specific coding grating picture, and extraction and to be measured highly corresponding grating are finished the detection to be measured position height as specific coding.
The described focal plane pick-up unit that is used for projection lithography, wherein, described lighting source is broadband or monochromatic source.
The described focal plane pick-up unit that is used for projection lithography, wherein, described lighting source is Halogen lamp LED, xenon lamp, light emitting diode or laser instrument.
The described focal plane pick-up unit that is used for projection lithography, wherein, described specific coding grating has 0,1 two kind of transmitance, and utilizes binary coding that its transmitance is distributed and encode.
The described focal plane pick-up unit that is used for projection lithography, wherein, described specific coding grating vertically is made up of some code channels, form by printing opacity is alternate with lighttight rectangle region on every code channel, the rectangle region number of adjacent code channel is a twice relation, on the specific coding grating on the horizontal direction each position all corresponding with a fixing binary coding.
The described focal plane pick-up unit that is used for projection lithography, wherein, face to be measured is surface to be processed in the projection lithography, has the plane or the curved surface of direct reflection, diffuse reflective nature.
The described focal plane pick-up unit that is used for projection lithography, wherein, described sensitive detection parts are a kind of in the linear array of light signal sensitivity or the face battle array photodetection class device.
The described focal plane pick-up unit that is used for projection lithography, wherein, described sensitive detection parts are CCD planar array detector, line array CCD detector or cmos device.
The invention has the beneficial effects as follows: replace traditional slit by utilizing encode grating, improved the focusing test measurement range, and only utilized the CCD central area, or linear array photoelectric detector record coding grating picture, reduced requirement to CCD lens imaging quality.And the present invention adopts the specific coding grating, only need utilize the linear array photodetector, or the core of face battle array photodetector looks like to survey to its grating, has reduced the requirement to the imaging system camera lens, is beneficial to realize that high-precision focal plane measures.
Description of drawings
Fig. 1 is focal plane pick-up unit schematic diagram among the present invention
Fig. 2 is the encode grating synoptic diagram
Primary clustering symbol description in the accompanying drawing:
Lighting source 1; Specific coding grating 2; Projection imaging system 3; First catoptron 4; To be measured 5; Second catoptron 6; Focusing test mark amplification system; Sensitive detection parts 8.
Embodiment
The present invention utilizes the binary coding grating to replace traditional slit, realizes on a large scale, and high-precision focal plane detects.
The present invention is made up of lighting source 1, specific coding grating 2, projection imaging system 3, first catoptron 4, to be measured 5, second catoptron 6, focusing test mark amplification system 7 and sensitive detection parts 8.The illumination of being sent by lighting source 1 is mapped on the specific coding grating 2, after the light after absolute encode grating 2 modulation is by projection imaging system 3, be reflected mirror 4 projection imagings to be measured 5 on, after to be measured 5 reflection, enter by catoptron 6 and to be detected device 8 after the focusing test mark amplification system 7 and to receive.Utilize detector 8 to receive the specific coding grating pictures that the position changes with to be measured 5 height change, by extract with to be measured 5 highly corresponding grating as specific coding, finish detection to be measured 5 position height.
Lighting source 1 of the present invention adopts broadband or monochromatic source, and described broadband or monochromatic source comprise light source common in Halogen lamp LED, xenon lamp, LED, laser instrument or the engineering.
Specific coding grating 2 of the present invention, as the focusing test mark have 0,1 two kind of transmitance, and utilize binary coding that its transmitance is distributed and encode.The specific coding grating vertically is made up of some code channels, form by printing opacity is alternate with lighttight rectangle region on every code channel, the rectangle region number of adjacent code channel is a twice relation, on the specific coding grating on the horizontal direction each position all corresponding with a fixing binary coding.Resolution requirement is high more, and measurement range requires big more, and code channel is just many more, for a specific coding grating with N position coding, must have N bar code channel.
To be measured 5 of the present invention is surfaces to be processed in the projection lithography, is plane or the curved surface with direct reflection, diffuse reflective nature.
Sensitive detection parts 8 of the present invention not only can be the CCD planar array detector, can also be the line array CCD detectors, a kind of in the linear array of light signal sensitivity or the face battle array photodetection class device such as cmos device.
For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.
Focal plane pick-up unit of the present invention comprises as shown in Figure 1: be made up of lighting source 1, specific coding grating 2, projection imaging system 3, catoptron 4, to be measured 5, catoptron 6, focusing test mark amplification system 7 and sensitive detection parts 8.
Lighting source 1 adopts LED as light source, in the course of work, the illumination that lighting source 1 sends is mapped on the specific coding grating 2, through absolute encode grating 2 modulation backs by projection imaging system 3 backs and catoptron 4 projection imagings to be measured 5 on, to be measured 5 is the plane to be processed with direct reflection character.After the grating picture is reflected by to be measured 5, after catoptron 6 and amplification system 7, receive by sensitive detection parts 8.Sensitive detection parts 8 are the linear array photoelectric detector.
Change the focusing test system based on principle of triangulation, when highly changing for to be measured, the grating picture that detector 8 receives will change.The present invention adopts the specific coding grating, and each position is all corresponding with a coding in the grating, receives the grating picture and to its demodulation, just can obtain the correspondence coding of to be measured 5 height of living in this moment by linear array detector.Obtain the ideal image focal plane height of photoetching projection objective lens by experiment, and this focusing test system is demarcated, obtain the grating picture coding of ideal image focal plane correspondence.In the course of work, by corresponding coding of contrast ideal image focal plane and real-time to be measured 5 the height coding that obtains of measuring, just can calculate to be measured 5 difference in height with desirable focal plane, on this basis to be measured 5 height is adjusted, thereby guaranteed that to be measured 5 is positioned on the desirable focal plane of object lens all the time.
In the present embodiment, the incident angle θ of system is 7 °, and projection imaging system 3 reduction magnification are 5 times, and the enlargement ratio of amplification system 7 is 5 times, and the single live width of linear array photodetector is 5 μ m.According to principle of triangulation, when substrate height change h, the amount of movement of viewed grating picture is about 2h, in order to reach the focal plane change detection precision of 1 μ m, and the measurement range of 32 μ m, the specific coding grating that adopts should have 5 codings, promptly has 5 code channels, and its structure as shown in Figure 2.Specific coding grating 2 has 0,1 two kind of transmitance, vertically is made up of 5 code channels, forms by printing opacity is alternate with lighttight rectangle region on every code channel, and the rectangle region number of adjacent code channel is the twice relation, minimum grating rectangle width 10 μ m.
The content that the present invention does not elaborate is those skilled in the art's common practise.
The above only is a concrete embodiment of the present invention, is not limited to the present invention.All any modifications of being made within the spirit and principles in the present invention are equal to replacement or improvement etc., all should be included in protection scope of the present invention.
Claims (8)
1. focal plane pick-up unit that is used for projection lithography, primary structure is:
One lighting source, the illumination of sending is mapped on the specific coding grating, through the light after the absolute encode grating modulation by behind the projection imaging system by the first catoptron projection imaging to be measured on, after to be measured reflection, receive by detector after entering focusing test mark amplification system by second catoptron; To be measured height change, the specific coding grating that detector is received looks like to change, and utilizes detector to receive specific coding grating picture, and extraction and to be measured highly corresponding grating are finished the detection to be measured position height as specific coding.
2. the focal plane pick-up unit that is used for projection lithography according to claim 1, wherein, described lighting source is broadband or monochromatic source.
3. the focal plane pick-up unit that is used for projection lithography according to claim 1 and 2, wherein, described lighting source is Halogen lamp LED, xenon lamp, light emitting diode or laser instrument.
4. the focal plane pick-up unit that is used for projection lithography according to claim 1, wherein, described specific coding grating has 0,1 two kind of transmitance, and utilizes binary coding that its transmitance is distributed and encode.
5. according to claim 1 or the 4 described focal plane pick-up units that are used for projection lithography, wherein, described specific coding grating vertically is made up of some code channels, form by printing opacity is alternate with lighttight rectangle region on every code channel, the rectangle region number of adjacent code channel is a twice relation, on the specific coding grating on the horizontal direction each position all corresponding with a fixing binary coding.
6. the focal plane pick-up unit that is used for projection lithography according to claim 1, wherein, face to be measured is surface to be processed in the projection lithography, has the plane or the curved surface of direct reflection, diffuse reflective nature.
7. the focal plane pick-up unit that is used for projection lithography according to claim 1, wherein, described sensitive detection parts are a kind of in the linear array of light signal sensitivity or the face battle array photodetection class device.
8. according to claim 1 or the 7 described focal plane pick-up units that are used for projection lithography, wherein, described sensitive detection parts are CCD planar array detector, line array CCD detector or cmos device.
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| CN2011102246197A CN102243138A (en) | 2011-08-05 | 2011-08-05 | Focal plane detection device for projection lithography |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103293867A (en) * | 2012-03-05 | 2013-09-11 | 上海微电子装备有限公司 | Pre-alignment device and method of square substrates |
| CN104154884A (en) * | 2014-08-25 | 2014-11-19 | 长春华特光电技术有限公司 | Direct-reading type photoelectric collimation angular instrument with yardstick |
| CN105223780A (en) * | 2014-06-03 | 2016-01-06 | 上海微电子装备有限公司 | Projection slit and focusing and leveling sensor |
| WO2016107573A1 (en) * | 2014-12-31 | 2016-07-07 | 上海微电子装备有限公司 | Pre-alignment measuring device and method |
| CN108139696A (en) * | 2015-10-15 | 2018-06-08 | Asml荷兰有限公司 | Shape measurement system |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002055435A (en) * | 2000-08-09 | 2002-02-20 | Toshiba Corp | Test mark as well as focus using the same and method of measuring aberration |
| US20070246646A1 (en) * | 2006-04-24 | 2007-10-25 | Lum Chee F | Optical projection encoder |
| CN101221372A (en) * | 2008-01-25 | 2008-07-16 | 中国科学院上海光学精密机械研究所 | In-situ detection system and detection method for even aberration of projection objective of photoetching machine |
| CN101806587A (en) * | 2010-04-29 | 2010-08-18 | 浙江师范大学 | Optical three-dimensional measurement method with absolute phase measurement |
| CN102087483A (en) * | 2010-12-27 | 2011-06-08 | 中国科学院光电技术研究所 | Optical system for focal plane detection in projection lithography |
| CN102096377A (en) * | 2009-12-10 | 2011-06-15 | 北大方正集团有限公司 | Method and device for inputting process parameters to dose controller |
| CN102141738A (en) * | 2011-04-02 | 2011-08-03 | 中国科学院光电技术研究所 | Nanometer-level automatic focusing system for projection lithography |
-
2011
- 2011-08-05 CN CN2011102246197A patent/CN102243138A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002055435A (en) * | 2000-08-09 | 2002-02-20 | Toshiba Corp | Test mark as well as focus using the same and method of measuring aberration |
| US20070246646A1 (en) * | 2006-04-24 | 2007-10-25 | Lum Chee F | Optical projection encoder |
| CN101221372A (en) * | 2008-01-25 | 2008-07-16 | 中国科学院上海光学精密机械研究所 | In-situ detection system and detection method for even aberration of projection objective of photoetching machine |
| CN102096377A (en) * | 2009-12-10 | 2011-06-15 | 北大方正集团有限公司 | Method and device for inputting process parameters to dose controller |
| CN101806587A (en) * | 2010-04-29 | 2010-08-18 | 浙江师范大学 | Optical three-dimensional measurement method with absolute phase measurement |
| CN102087483A (en) * | 2010-12-27 | 2011-06-08 | 中国科学院光电技术研究所 | Optical system for focal plane detection in projection lithography |
| CN102141738A (en) * | 2011-04-02 | 2011-08-03 | 中国科学院光电技术研究所 | Nanometer-level automatic focusing system for projection lithography |
Non-Patent Citations (4)
| Title |
|---|
| 刘维一等: "彩色组合编码条纹光栅轮廓术", 《光学学报》 * |
| 施伟杰等: "基于镜面焦面检测对准标记的套刻性能原位测量技术", 《光学学报》 * |
| 盖绍彦等: "基于数字投影仪的三维轮廓检测系统", 《东南大学学报（自然科学版）》 * |
| 相里斌等: "使用位敏探测器PSD的焦面检测方法", 《测试技术学报》 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103293867A (en) * | 2012-03-05 | 2013-09-11 | 上海微电子装备有限公司 | Pre-alignment device and method of square substrates |
| CN103293867B (en) * | 2012-03-05 | 2015-07-22 | 上海微电子装备有限公司 | Pre-alignment device and method of square substrates |
| CN105223780A (en) * | 2014-06-03 | 2016-01-06 | 上海微电子装备有限公司 | Projection slit and focusing and leveling sensor |
| CN104154884A (en) * | 2014-08-25 | 2014-11-19 | 长春华特光电技术有限公司 | Direct-reading type photoelectric collimation angular instrument with yardstick |
| WO2016107573A1 (en) * | 2014-12-31 | 2016-07-07 | 上海微电子装备有限公司 | Pre-alignment measuring device and method |
| CN105807579A (en) * | 2014-12-31 | 2016-07-27 | 上海微电子装备有限公司 | Silicon chip and substrate prealignment measurement device and method |
| CN105807579B (en) * | 2014-12-31 | 2018-10-16 | 上海微电子装备（集团）股份有限公司 | A kind of silicon chip and substrate prealignment measuring device and method |
| US10197390B2 (en) | 2014-12-31 | 2019-02-05 | Shanghai Micro Electronics Equipment (Group) Co., Ltd. | Pre-alignment measurement device and method |
| CN108139696A (en) * | 2015-10-15 | 2018-06-08 | Asml荷兰有限公司 | Shape measurement system |
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Application publication date: 20111116 |