CN118938605A - A split-amplitude collimated flat-top beam laser interference lithography system - Google Patents
A split-amplitude collimated flat-top beam laser interference lithography system Download PDFInfo
- Publication number
- CN118938605A CN118938605A CN202410993763.4A CN202410993763A CN118938605A CN 118938605 A CN118938605 A CN 118938605A CN 202410993763 A CN202410993763 A CN 202410993763A CN 118938605 A CN118938605 A CN 118938605A
- Authority
- CN
- China
- Prior art keywords
- flat
- reflector
- laser
- amplitude
- interference lithography
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/70408—Interferometric lithography; Holographic lithography; Self-imaging lithography, e.g. utilizing the Talbot effect
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/09—Beam shaping, e.g. changing the cross-sectional area, not otherwise provided for
- G02B27/0927—Systems for changing the beam intensity distribution, e.g. Gaussian to top-hat
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/18—Diffraction gratings
- G02B5/1847—Manufacturing methods
- G02B5/1857—Manufacturing methods using exposure or etching means, e.g. holography, photolithography, exposure to electron or ion beams
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Diffracting Gratings Or Hologram Optical Elements (AREA)
Abstract
本发明公开了一种分振幅型准直平顶光束激光干涉光刻系统，属于微纳结构技术领域，包括激光器、第一反射镜、第一半波片、偏振分光棱镜、第二半波片、第二反射镜、第三反射镜、第四反射镜、第五反射镜、第六反射镜、条纹锁定系统、激光光束整形系统和干涉系统。本发明采用上述的一种分振幅型准直平顶光束激光干涉光刻系统，光束通过光学系统后形成大面积、能量分布均匀的准直平顶光束，可实现占空比均匀性强的高性能光栅制造，满足高精度的纳米光栅加工需求。
The present invention discloses a split amplitude collimated flat-top beam laser interference lithography system, which belongs to the field of micro-nano structure technology, and includes a laser, a first reflector, a first half-wave plate, a polarization beam splitter, a second half-wave plate, a second reflector, a third reflector, a fourth reflector, a fifth reflector, a sixth reflector, a fringe locking system, a laser beam shaping system and an interference system. The present invention adopts the above-mentioned split amplitude collimated flat-top beam laser interference lithography system, and the light beam forms a large-area, uniformly distributed collimated flat-top beam after passing through the optical system, which can realize high-performance grating manufacturing with strong duty cycle uniformity and meet the high-precision nano grating processing requirements.
Description
Technical Field
The invention relates to the technical field of micro-nano structures, in particular to an amplitude-division type collimated flat-top beam laser interference lithography system.
Background
The grating is used as a micro-nano optical element with a periodic unit structure and plays a vital role in the fields of optical precision instruments, optical precision measurement, laser pulse compression and the like. The high-end application brings forward the performance requirements of high diffraction efficiency, small wave aberration, low stray light and the like in the full-caliber range for the grating device. Therefore, it is important to achieve fabrication of high structural profile uniformity gratings over a large area.
Laser interference lithography uses dual beam interference exposure to produce periodic micro-nano structures. The method has the remarkable advantages of no mask, high precision, high manufacturing efficiency, low cost and the like, and is the mainstream technology for manufacturing the large-area grating at present. However, since the energy profile of the fundamental mode beam emitted from the laser is gaussian (gaussian beam), it has problems that the exposure dose distribution is uneven and the uniformity of the grating duty ratio is poor over a wide area. In the prior art, the energy distribution uniformity of an exposure area is improved by apodizing the light spots after laser beam expansion, so that great energy loss is generated, and the laser energy utilization rate is low.
Meanwhile, the current laser interference lithography system mainly comprises a wave front type light path structure and an amplitude type light path structure. The existing collimation flat-top beam interference lithography system is of a front-type of a wave division, can not provide a stripe locking function through technologies such as an acousto-optic modulator (AOM) or a piezoelectric actuator, is difficult to resist the influence of environmental factors, and can not meet the manufacturing requirements of high-performance gratings. The flat-top optical elements used in the existing amplitude-division flat-top beam interference lithography system are all focusing beam shapers, only a flat-top beam can be obtained at a specific position, and the flat-top optical elements have extremely large wave aberration and cannot meet the performance requirements of high duty ratio uniformity and low diffraction wavefront error of a high-performance grating.
Accordingly, it would be desirable to provide a collimated flat-top beam laser interference lithography system with high duty cycle uniformity, low diffraction wavefront error, and high energy utilization.
Disclosure of Invention
The invention aims to provide an amplitude-division type collimation flat-top beam laser interference lithography system, which can shape Gaussian beams into collimation flat-top beams with uniform energy distribution under the amplitude-division type optical configuration, and solves the problem that the energy utilization rate and the grating duty ratio uniformity of the existing laser interference lithography technology are not compatible.
In order to achieve the above purpose, the invention provides an amplitude-division type collimated flat-top beam laser interference lithography system, which comprises a laser, a first reflecting mirror, a first half-wave plate, a polarization beam splitter prism, a second half-wave plate, a second reflecting mirror, a third reflecting mirror, a fourth reflecting mirror, a fifth reflecting mirror, a sixth reflecting mirror, a stripe locking system, a laser beam shaping system and an interference system;
the optical path structure of the laser interference lithography system is as follows:
the light emitted by the laser sequentially passes through the first reflecting mirror, the first half-wave plate and the polarization beam splitter prism, and is split into transmitted P polarized light and reflected S polarized light by the polarization beam splitter prism;
The transmitted P polarized light is adjusted to S polarization through a second half-wave plate, and then sequentially passes through a second reflecting mirror, a third reflecting mirror, a stripe locking system, a laser beam shaping system and an interference system;
the reflected S-polarized light passes through the fourth reflector, the fifth reflector, the sixth reflector, the stripe locking system, the laser beam shaping system and the interference system in sequence.
Preferably, the fringe locking system comprises an acousto-optic modulator and control circuitry.
Preferably, the laser beam shaping system comprises a beam expanding optical system and a flat top optical system.
Preferably, the beam expanding optical system comprises a first beam expander, a first collimator, a second beam expander and a second collimator;
The light path structure of the beam expanding optical system is as follows:
The two beams of light respectively pass through the first beam expander, the first collimating lens, the flat-top optical system, the second beam expander and the second collimating lens in sequence.
Preferably, the first beam expander and the second beam expander have different specifications of lenses, and the first collimating lens and the second collimating lens have different specifications of lenses.
Preferably, the flat top optical system comprises a flat top optical element.
Preferably, the interference system includes a stage having a photoresist coated substrate disposed thereon.
Preferably, the first beam expander and the first collimator expand the incident beam to a size meeting the beam radius requirement of the flat top optical element; the second beam expander and the second collimator expand the shaped flat-top beam to a size meeting the grating manufacturing area requirement.
Therefore, the amplitude-division type collimation flat-top beam laser interference lithography system has the following beneficial effects:
(1) The system stability can be improved by utilizing a stripe locking system;
(2) The flat-top optical element is utilized to finish beam shaping, so that the laser energy utilization rate can be improved, and the manufacture of a large-area high-precision grating is realized;
(3) The light beam passes through the optical system to form a large-area collimated flat-top light beam with uniform energy distribution, so that high-performance grating manufacture with high duty ratio uniformity can be realized, and the processing requirement of high-precision nano gratings is met;
(4) The system can finish high-precision laser interference lithography and manufacture high-precision gratings with high duty ratio uniformity.
The technical scheme of the invention is further described in detail through the drawings and the embodiments.
Drawings
FIG. 1 is a schematic diagram of the duty cycle of a grating fabricated from a non-uniform beam and a flat top beam in accordance with the present invention;
FIG. 2 is a schematic diagram of the amplitude-division type collimated flat-top beam laser interference lithography system;
FIG. 3 is a plot of the fringe intensity profile at A in FIG. 2;
FIG. 4 is a schematic diagram of a beam expanding and shaping optical system according to the present invention;
FIG. 5 is a graph of experimentally measured beam energy distribution at B in FIG. 4;
FIG. 6 is a graph of the experimentally measured beam energy distribution at C in FIG. 4;
FIG. 7 is a graph of experimentally measured beam energy distribution at D in FIG. 4;
FIG. 8 is an experimental measured beam energy distribution at E in FIG. 4;
FIG. 9 is a diagram of a typical structure of a grating at the center, waist, and edge of a sample of a grating manufactured by a laser interference lithography system according to the present invention, as measured by a scanning electron microscope;
reference numerals
1. A laser; 2. a first mirror; 3. a first half-wave plate; 4. a polarization beam splitter prism; 5. a second half-wave plate; 6. a second mirror; 7. a third mirror; 8.a fourth mirror; 9. a fifth reflecting mirror; 10. a sixth mirror; 11. an acousto-optic modulator; 12. a first beam expander; 13. a first collimating mirror; 14. a flat top optical element; 15. a second beam expander; 16. a second collimating mirror; 17. a work table; 18. a laser beam shaping system.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
Examples
As shown in fig. 1-8, the present invention provides an amplitude-division type collimated flat-top beam laser interference lithography system, which comprises a laser 1, a first reflecting mirror 2, a first half-wave plate 3, a polarization splitting prism 4, a second half-wave plate 5, a second reflecting mirror 6, a third reflecting mirror 7, a fourth reflecting mirror 8, a fifth reflecting mirror 9, a sixth reflecting mirror 10, a fringe locking system, a laser beam shaping system 18 and an interference system. The wavelength of the laser 1 output laser beam is in the existing photosensitive spectral range of the photoresist.
The optical path structure of the system is as follows: the light emitted by the laser 1 sequentially passes through the first reflecting mirror 2, the first half-wave plate 3 and the polarization splitting prism 4, and is split into transmitted P polarized light and reflected S polarized light by the polarization splitting prism 4; the transmitted P polarized light is adjusted to S polarization through the second half wave plate 5, and then sequentially passes through the second reflecting mirror 6, the third reflecting mirror 7, the stripe locking system, the laser beam shaping system 18 and the interference system; the reflected light passes through the fourth mirror 8, the fifth mirror 9, the sixth mirror 10, the fringe locking system, the laser beam shaping system 18, and the interference system in this order.
The laser light emitted from the laser 1 is reflected by the first reflecting mirror 2, enters the first half-wave plate 3, and then enters the polarization splitting prism 4 to be split into two beams of light having mutually perpendicular vibration directions. One beam is transmitted P polarized light, and the light path direction is not changed and passes through the polarization beam splitter prism 4; the other beam is reflected S polarized light, and exits along the direction perpendicular to the original light path. By rotating the first half wave plate 3, the adjustment of the energy ratio of the two light beams split by the polarization splitting prism 4 can be realized.
The system can change the incident light angle by adjusting the reflecting mirror so as to change the period for preparing the grating, and the light beam energy uniformity is not changed.
The P light transmitted by the polarization splitting prism 4 passes through the second half-wave plate 5, and is adjusted by the half-wave plate, so that the same polarization direction as the S light reflected by the polarization splitting prism 4 is maintained. The two beams of light are mutually coherent light and are respectively regulated by a second reflecting mirror 6, a third reflecting mirror 7, a fourth reflecting mirror 8, a fifth reflecting mirror 9 and a sixth reflecting mirror 10.
The fringe locking system comprises an acousto-optic modulator 11 and control circuitry, and the two acousto-optic modulators 11 in FIG. 2 are identical. The control circuit comprises a photoelectric detector, a reference grating, an A/D conversion data acquisition card, an upper computer, a digital IO card and an acousto-optic modulator driver. The fringe locking system adopts a photoelectric detector to detect moire fringe disturbance generated by the equivalent period reference grating, the measuring signal is amplified and then is input into an upper computer through an A/D conversion data acquisition card, the upper computer processes input data in real time, analyzes and extracts noise signals, an acousto-optic modulator is arranged to compensate signal frequency difference according to noise characteristics, the signals are converted into binary digital signals, and the binary digital signals are transmitted to an acousto-optic modulator driver through a digital IO card, so that fringe locking of interference fringes is realized. The phase locked beam is completed and subsequently enters the laser beam shaping system 18.
The laser beam shaping system 18 includes a beam expanding optical system and a flat top optical system. The optical path structure of the laser beam shaping system 18 is as follows: the two beams respectively pass through the first beam expander 12, the first collimator 13, the flat-top optical system, the second beam expander 15 and the second collimator 16 in sequence.
The beam expanding optical system includes a first beam expander 12, a first collimator 13, a second beam expander 15, and a second collimator 16. The light path structure of the beam expanding optical system is as follows: the two beams respectively pass through the first beam expander 12, the first collimator 13, the flat-top optical system, the second beam expander 15 and the second collimator 16 in sequence.
The flat top optical system includes a flat top optical element 14. Typical cascade asphere-based flat top optical elements 14 may output a beam energy non-uniformity of less than 5% and a transmittance of greater than 95%. The rated incident gaussian beam size of the flat top optical element 14 is 6mm in spot diameter, and the uniformity of the energy of the beam output by the flat top optical element 14 is the highest.
The beam is first expanded by the first beam expander 12 to a size meeting the beam radius requirement of the flat top optical element 14, and then collimated by the first collimator 13, so as to form parallel light with a spot size meeting the requirement of the flat top optical element 14. The parallel light is still gaussian. The light beam enters the flat-top optical element 14, is shaped by the flat-top beam shaper, forms a flat-top light beam with uniform energy distribution, and then is emitted, and then is expanded and collimated by the second beam expander 15 and the second collimating lens 16 to form a collimated flat-top light beam with large area and uniform energy distribution, and the collimated flat-top light beam of the expanded beam meets the requirement of the grating manufacturing area. The first beam expander 12 and the second beam expander 15 have different specifications of lenses; the first collimating mirror 13 and the second collimating mirror 16 are different in specifications of lenses.
The wavelength of the beam output by the laser 1 is 413.1nm, the diameter of the beam is 1.3mm, the beam passes through the first beam expander 12, and the beam is expanded and collimated into 6mm after passing through the first collimator 13, so that the requirement of the flat-top optical element 14 is met; the diameter of the beam is 6mm when the beam exits from the flat-top optical element 14, and the beam is expanded and collimated into a parallel flat-top beam with the diameter of 30mm after passing through the second beam expander 15 and the second collimator 16.
The interference system includes a stage 17, and a photoresist-coated substrate is disposed on the stage 17. The two collimated flat top lights emitted through the second collimator lens 16 interfere on the table 17. The two beams of incident light carry out interference exposure on the photoresist coated on the substrate, so that the manufactured grating has large area and high uniformity of the duty ratio. Referring to fig. 9, the uniformity of the grating structure in the three ring belt regions is good, which indicates that the uniformity of the duty ratio of the grating prepared by the system is high.
Table 1 shows that the maximum deviation of the grating duty ratio manufactured by the method provided by the invention is less than +/-3% as shown in the table 1.
Table 1 grating duty cycle
Therefore, the amplitude-division type collimation flat-top beam laser interference lithography system has the characteristics of high energy utilization rate, high grating duty cycle uniformity, low grating diffraction wavefront error and capability of performing fringe locking, and has advantages in the aspect of manufacturing high-performance gratings.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention and not for limiting it, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that: the technical scheme of the invention can be modified or replaced by the same, and the modified technical scheme cannot deviate from the spirit and scope of the technical scheme of the invention.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410993763.4A CN118938605A (en) | 2024-07-24 | 2024-07-24 | A split-amplitude collimated flat-top beam laser interference lithography system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410993763.4A CN118938605A (en) | 2024-07-24 | 2024-07-24 | A split-amplitude collimated flat-top beam laser interference lithography system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118938605A true CN118938605A (en) | 2024-11-12 |
Family
ID=93347413
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410993763.4A Pending CN118938605A (en) | 2024-07-24 | 2024-07-24 | A split-amplitude collimated flat-top beam laser interference lithography system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118938605A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6304318B1 (en) * | 1998-06-30 | 2001-10-16 | Canon Kabushiki Kaisha | Lithography system and method of manufacturing devices using the lithography system |
| US20170329146A1 (en) * | 2016-05-12 | 2017-11-16 | National Sun Yat-Sen University | Laser interference lithography system with flat-top intensity profile |
| KR20190054764A (en) * | 2017-11-14 | 2019-05-22 | 연세대학교 산학협력단 | Scanning Interference Lithography System with Real-time Error Correction |
| CN116224722A (en) * | 2023-02-15 | 2023-06-06 | 中国科学院上海光学精密机械研究所 | Holographic grating double-beam interference exposure system based on beam scanning dodging and exposure method thereof |
-
2024
- 2024-07-24 CN CN202410993763.4A patent/CN118938605A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6304318B1 (en) * | 1998-06-30 | 2001-10-16 | Canon Kabushiki Kaisha | Lithography system and method of manufacturing devices using the lithography system |
| US20170329146A1 (en) * | 2016-05-12 | 2017-11-16 | National Sun Yat-Sen University | Laser interference lithography system with flat-top intensity profile |
| KR20190054764A (en) * | 2017-11-14 | 2019-05-22 | 연세대학교 산학협력단 | Scanning Interference Lithography System with Real-time Error Correction |
| CN116224722A (en) * | 2023-02-15 | 2023-06-06 | 中国科学院上海光学精密机械研究所 | Holographic grating double-beam interference exposure system based on beam scanning dodging and exposure method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103235489B (en) | Method for variable period multi-beam interference photoetching | |
| CN110837214B (en) | Scanning Interference Lithography System | |
| US8094374B2 (en) | Beam shaping module | |
| Xue et al. | Patterning nanoscale crossed grating with high uniformity by using two-axis Lloyd’s mirrors based interference lithography | |
| Breidne et al. | Blazed holographic gratings | |
| CN110836726A (en) | Device and method for detecting order of any singular point light beam | |
| CN110806680B (en) | Laser Interference Lithography System | |
| US10042173B2 (en) | Laser interference lithography system with flat-top intensity profile | |
| CN108983560A (en) | Interference photoetching system with controllable period and direction | |
| CN116295038B (en) | Nanoscale two-dimensional displacement measurement device and method based on metasurface grating | |
| Poleshchuk et al. | Diffractive optical elements: fabrication and application | |
| CN112558203B (en) | A device and method for independent phase control of radial and angular cylindrical vector beams | |
| CN103424996B (en) | A kind of optical machining system and method | |
| Oemrawsingh et al. | High-dimensional mode analyzers for spatial quantum entanglement | |
| CN111352182B (en) | Exposure method of polarizer holographic grating | |
| CN103135363B (en) | Device for producing projection photo-etching illumination mode | |
| CN112612142B (en) | Optical system for generating quasi-flat-top round light spot | |
| CN118938605A (en) | A split-amplitude collimated flat-top beam laser interference lithography system | |
| Poleshchuk | Fabrication and application of diffractive optical elements | |
| CN114905146B (en) | Middle infrared laser beam shaping device and method for processing special-shaped piece | |
| CN102023387A (en) | Array annular photon sieve homogenizer and manufacturing method thereof | |
| Poleshchuk | Computer generated holograms for aspheric optics testing | |
| CN108551078A (en) | A kind of semiconductor laser beam merging apparatus | |
| CN209860346U (en) | Wavelength tuning device based on precision rotary table | |
| CN113946008A (en) | Phase and amplitude combined modulation composite zone plate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |