Iceassisted electron beam lithography of graphene jules a gardener1 and j a golovchenko1,2 1 department of physics, harvard university, cambridge, ma 028, usa 2 school of engineering and applied sciences, harvard university, cambridge, ma 028, usa email. Discover nanoengineering beyond electron beam lithography. Large area beams and multibeam systems are the current. Electron beam exposure the electron beam exposure tool used in our study is a modified scanning electron microscope hitachi s 450 controlled by a computer for high resolution elec tron beam lithography. Zeiss unigis gis gas injection system is a new single gas injection system used for ion or electron beam induced deposition ibid ebid of precursors such as platinum, tungsten or carbon with zeiss. Achieving the highest possible resolution using scanning electron beam lithography sebl has become an increasingly urgent problem in recent years, as advances in various nanotechnology applications have driven demand for feature sizes well into the sub10nm domain. Basics of microscopebased lithography electron beams have been used for lithography for decades 1,2 and a lithography system can easily be added to nearly all modern electron. Electron beam lithography often abbreviated as e beam lithography, ebl is the practice of scanning a focused beam of electrons to draw custom shapes on a surface covered with an electron sensitive film called a resist exposing. Facile electronbeam lithography technique for irregular.
An ebl instr ument is a r esult of working a scanning electron microscope. We report on the resolution limits of electron beam lithography ebl in the conventional polymethylmethacrylate pmma organic resist. We achieved 2 nm isolated feature size and 5 nm halfpitch in hydrogen silsesquioxane. Electronbeam lithography often abbreviated as e beam lithography, ebl is the practice of scanning a focused beam of electrons to draw custom shapes on a surface covered with an electron sensitive film called a resist exposing. Electron beam lithography ebl is one of the key fabrication techniques that. Overview of e beam lithography focused beam of electrons accurately. To obtain this item, you may purchase the complete book in print format on. Electron beams are irradiated from the electron source, and tightly focused by electron. Electron beam lithography ebl is the primary method for patterning arbitrary features, but ebl has not reliably provided sub4 nm patterns. Langmuirblodgett resist films for microlithography by. Derived from the early scanning electron microscopes, the technique in brief consists of scanning a beam. Guaranteed superior system specs and the worlds smallest beam. Electron beam lithography basics a resist, a long chained polymer, is spun onto a substrate usually silicon. Achieving the highest possible resolution using scanningelectronbeam lithography sebl has become an increasingly urgent problem in recent years, as advances in various nanotechnology applications.
Achieving sub10nm resolution using scanning electron. Jeol provides valuable applications support, comprehensive training, and award. Atomic fabrication with electron beams and scanning probes. Scanning electron microscope sem industrial equipment for thinfilm formation and material processing. It makes use of a highly energetic, tightly focused electron beam, which is scanned over a sample coated with an electron sensitive resist. Electronbeam lithography is the practice of scanning a focused beam of electrons on a surface coated with a film that is resistant to electrons called a resist, in order to draw custom shapes. The turnkey 150 e beam lithography system the system consists mainly of a scanning electron microscope sem integrated with hardware for doing lithographic electron beam exposures. Lithography is now a complex tool at the heart of a technological process for manufacturing micro and nanocomponents.
Illustration of several signals generated by the electron beamspecimen interaction in the scanning electron microscope and the regions from which the signals can be detected. The electron beam is controlled by a computer in accordance with a predefined program, therefore there is no need for templates or masks. The few competing techniques that have achieved this resolution are orders of magnitude slower than ebl. Limiting factors in sub10 nm scanningelectronbeam lithography bryan cord,a joel yang, and huigao duan massachusetts institute of technology, cambridge, massachusetts 029. The e beam is swept across the entire surface, pixel by pixel, with the beam. Patterning materials efficiently at the smallest length scales is a longstanding challenge in nanotechnology. Guaranteed superior system specs and the worlds smallest beam size paired with a. If the sem image window remains solid black after turning on the beam, the image scanning is being frozen the freeze button above the image window in figure 5 is in solid green. Derived from the early scanning electron microscopes, the technique in brief consists of scanning a beam of electrons across a surface covered with a resist film.
The first electron beam lithography machines, based on the scanning electron. We achieved 2 nm isolated feature size and 5 nm halfpitch in hydrogen silsesquioxane resist. Compact, uncompromised and affordable multi technique electron beam lithography pioneer tm two is the ideal solution for all universities and scientists with equal requirements for both an electron beam lithography ebl system and an analytical scanning electron microscope sem. Derived from the early scanning electron microscopes, the technique consists of scanning a beam of electrons across a surface covered with a resist film sensitive to those electrons, thus depositing energy in the. Sem imaging meets electron beam lithography compact, uncompromised and affordable multi technique electron beam lithography. Shortly thereafter came the discovery that the common poly. Those cad files can then be converted to a machinespecific format for say ebeam patterning. After completion of the process, structures can be observed in scanning electron. Electrostatically focused addressable field emission array. Pattern design using designcad lt, the generation of npgs run files, coating of samples with e beam. Derived from the early scanning electron microscopes, the technique in brief consists of. Electron beam lithography ebl is an emphasized technique for fabricating.
Derived from the early scanning electron microscopes, the technique in brief. The electron beam scans the image according to a pattern defined on a cad file. Resolution limits of electronbeam lithography toward the. Electron throughput severely limits using e beam technology for large scale production. The ability to meet stringent linewidth control and pattern. As might be expected, larger data files are more susceptible to datarelated. Furthermore, we measured the energy loss in the resist using electron energy. Ebeam nanolithography integrated with scanning electron microscope joe nabity, lesely anglin campbell, mo zhu, and weilie zhou 1. Electron gun electron optical column resistcovered surface. Apr 27, 2005 electron beam lithography ebl is a special technique for making the very fine patterns that are needed by the electronics sector for integrated circuits.
Electron beams have been used for lithography for decades 1,2 and a lithog raphy system can easily be added to nearly all modern electron or ion micro scopes, including scanning electron microscope sem, scanning transmission electron microscope stem, focused ion beam fib, and dual semfib microscope models. The electron beam will start scanning on the sample surface and the sem image window will become brighter. Illustration of several signals generated by the electron beam specimen interaction in the scanning electron. Freely movable electron beam pen structure of eb lithography system. Large area beams and multi beam systems are the current. Jeol jsm 7600f scanning electron microscope purpose of this instrument. Facile electronbeam lithography technique for irregular and fragile substrates jiyoung chang,1,2,3,a qin zhou,1,2,3,a and alex zettl1,2,3,b 1department of physics, university of california at berkeley. Electron throughput severely limits using ebeam technology for large scale production. In particular, the characteristics of the scanning electron microscope sem.
Using a vector scanning electron beam, it requires no mask and has the ability to write a variety of pattern geometries giving it significant advantage over other lithographic techniques. Electron beam lithography, charging effect, algaasoninsulator, we investigate charging effect in electron beam lithography for patterning resist on electrically insulating substrate. Electron beam lithography ebl is one of the key fabrication techniques that allow us to create patterns at the nanoscale. Electronbeam lithography ebl scans a focused beam of electrons in a patterned fashion across a surface. We also analyzed the resolution limits of this technique by measuring the pointspread function at 200 kev.
Pattern design using designcad lt, the generation of npgs runfiles, coating of samples with ebeam resists, and the writing of those patterns with the sem will be discussed. Controlling these components by a computer allows transfer of any design in digital format to an exposure pattern. Electron beam lithography often abbreviated as e beam lithography is the practice of scanning a beam of electron s in a patterned fashion across a surface covered with a film called the resist, cite book last mccord firstm. Jeol has played a leading role in the development and evolution of scanning electron microscopes since the early 1960s. Electron beam lithography often abbreviated as e beam lithography is the practice of emitting a beam of electrons in a patterned fashion across a surface covered with a film called the. Fesem instrument must be the state of art, computer controlled user friendly system for high resolution imaging of metallic, nonmetallic, ceramics, crystals, thin films, polymers, metal oxides etc. We used thiolated polyethylene oxide peo sams on gold to fabricate chemically. We show that resolution can be pushed below 10 nm for isolated features and how dense arrays of periodic structures can be fabricated at a pitch of 30 nm, leading to a density close to 700 gbitin 2. The positive resists pmma and zep are polymers that are broken up by electron irradiation. The development of ebl tools started in the late 1960s ref. We also have access to an sembased electron beam direct writing system, which is capable of sub100nm resolution. Electron beam lithography ebl is a specialized technique for creating the extremely fine patterns. Electron beam lithography ebl is an important technique, which is used to design devices, systems and functional materials at the nano scale.
In electronbeam lithography you have a limited selection of resists. Electron beam lithography is a specialized technique for creating extremely fine patterns 50 nm. Electron beam lithography an overview sciencedirect topics. Pattern design using designcad lt, the generation of npgs run files, coating of samples with ebeam resists, and the writing of those patterns with the sem will be discussed. In scanning electron beam lithography the resist is exposed scanned by a focused beam of electrons consistently moving in the plane of the pattern. The 7th conference on advances in optoelectronics and micronanooptics aom 2018, xian, china. Electron beams are irradiated from the electron source, and tightly focused by electron lens onto the material to form an extremely small spot. Pioneer tm two is the ideal solution for all universities and scientists with equal requirements for both an electron beam lithography ebl system and an analytical scanning electron microscope sem. Basics of microscopebased lithography electron beams have been used for lithography for decades 1,2 and a lithography system can easily be added to nearly all modern electron or ion micro. Furthermore, we measured the energy loss in the resist using electron. We present chemical modification of self assembled monolayers sams using electron and ion beam lithographies. These patterns were transferred through the chromium and into the quartz via dry etching. We find that the charging effect can be mitigated without using a charge dissipation layer with an optimized exposure writing order strategy. Reducing insulating substrate charging in electron beam.
Jun 15, 2010 electron beam lithography ebl is one of the key fabrication techniques that allow us to create patterns at the nanoscale. It makes use of a highly energetic, tightly focused electron beam, which is scanned over a sample coated with an electronsensitive resist. Either scanning the beam by controlling its deflection from a computer sequential exposure or electron imaging through a special mask parallel exposure. Ebeam nanolithography integrated with scanning electron. Electron beam exposure the electron beam exposure tool used in our study is a modified scanning electron microscope hitachi s 450 controlled by a computer for high resolution elec tron beam lithography, developed by the nanjing electronic device institute in cooperation with south. Electrons from a scanning electron microscope are accelerated through the resist and into. Abstract from 7th conference on advances in optoelectronics and micronanooptics, xian, chile. Sep 06, 20 electron beam lithography often abbreviated as e beam lithography is the practice of emitting a beam of electrons in a patterned fashion across a surface covered with a film called the resist, exposing the resist and of selectively removing either exposed or nonexposed regions of the resist developing. A multidisciplinary technology, lithography continues to. Electron beam lithography system introduction to jeol.
The figure shows the structure of a typical spot beam type. Electron beam lithography ebl is a special technique for making the very fine patterns that are needed by the electronics sector for integrated circuits. We investigated electron beam lithography with an aberrationcorrected scanning transmission electron microscope. Facile electronbeam lithography technique for irregular and. Scanning electron microscope operation page 6 of 85 author. Electrons from a scanning electron microscope are accelerated through the resist and into the silicon where secondary electrons are produced. This is a variation of the electron beam lithography technique, using an focused ion beam fib instead of an electron beam. On the other hand, direct writing of patterns by scanning electron beam is a slow process and results in. However such sequential scanning of the image increases. Facile electron beam lithography technique for irregular and fragile substrates jiyoung chang,1,2,3,a qin zhou,1,2,3,a and alex zettl1,2,3,b 1department of physics, university of california at berkeley, berkeley, california 94720, usa. Compared to other techniques such as ebl, the principal advantage of spl is that it is a single step process with sub10 nm resolution.
Please see the pdf file for the additional information. Electron beams have been used for lithography for decades 1,2 and a lithog. An ebl instrument is a result of working a scanning electron microscope sem in. The technique, termed beam pen lithography, can toggle between near and far. A method for massively parallel electron beam lithography of semiconductor wafers, and also for massively parallel scanning electron microscopy. However, the electron beam exposure is an ingredient of ebl in which the resist treatment and development process are equally important. In a similar setup to scanning electon microscopes, an ion beam scans across the substrate surface and exposes electron sensitive coating. Jul 28, 2015 electron beam lithography electron beam lithography is a specialized technique for creating extremely fine patterns 50 nm. Aberrationcorrected electron beam lithography at the one. Electrostatically focused addressable field emission array chips for highspeed massively parallel maskless digital e beam direct write lithography and scanning electron. Structure observation at nanometer scale resolution.
An advanced microscopebased lithography system provides both manual and. Introduction electron beam lithography is a specialized technique for creating extremely fine patterns 50 nm. The ebl working principle is relatively simple and very similar to photolithography. The beam scanning is controlled by a 16bit external pattern generation system coupled with a computer assisted design software npgs. Scanning probe lithography of selfassembled monolayers. Highenergy electron beam lithography for nanoscale. In this miniaturization technique, largescale products are converted into smallscale structures. A more modern format is oasis, which few people use even though its. Scanning probe lithography spl describes a set of nanolithographic methods to pattern material on the nanoscale using scanning probes.
Electron beam lithography ebl allows users to write patterns with extremely high resolution, smaller than 10nm in size. Focused ion beam fabrication combined with electron beam lithography 6. The maximum working frequency is 50 khz and matches the limits of the scanning coils. It is a directwrite, maskless approach which bypasses the diffraction limit and can reach resolutions below 10 nm. Resolution limits of electronbeam lithog r aphy tow ard. Achieving sub10nm resolution using scanning electron beam. Pioneer tm two is the ideal solution for all universities and scientists with equal requirements for both an electron beam lithography ebl system and an analytical scanning electron.
Fundamentals of scanning electron microscopy 3 1 beam backscatterred electrons secondary electrons auger electrons characteristic xrays xray continuum figure 1. Scanning electron microscope with eds andebsd essential specifications. Electron scattering is the main limitation of writing small features. Supplementary information resolution limits of electron. Ebeam lithography ebl electron beam lithography often. Introduction to electron beam lithography bostjan bercic bostjan. These electrons travel through the resist where they break the bonds of the polymer chain. Electronbeam lithography is the practice of scanning a focused beam of electrons to draw.
Iceassisted electron beam lithography of graphene jules a gardener1 and j a golovchenko1,2 1 department of physics, harvard university, cambridge, ma 028, usa 2 school of engineering and. This is the most common file standard for electronbeam lithography and photolithography. It is a directwrite, maskless approach which bypasses the. E beam nanolithography integrated with scanning electron microscope joe nabity, lesely anglin campbell, mo zhu, and weilie zhou 1. Many cad programs produce the output format gdsii, also known as gds. Ebeam offers precision and accuracy yet requires enormous amounts of time money energy while ebeam lithography is one of the most accurate forms of microfabrication, the immense time, money and energy costs prevent it from gaining commercial acceptance. Threedimensional electron beam lithography using ice resists. In electron beam lithography ebl, predefined nanopatterns are generated by scanning a focused electron beam across an electron sensitive resist tone coated on a substrate, and the resist. Ebl resists negative tone and positive tone, using polymethyl methacrylate pmma in resists, and potential applications are considered here. Nanofabrication using electron beam lithography ebl. Electron microscopy facility wvu srf standard operating procedure. The prototype scalpel proofof lithography system spol uses 100 kev electrons to expose 14 x 14 mm fields at a resolution of 80 nm typically.
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