다중빔 리소그래피를 위한 초소형 컬럼의 전자빔 광학 해석에 관한 연구

이응기,Lee, Eung-Ki 한국반도체디스플레이기술학회 2009 반도체디스플레이기술학회지 Vol.8 No.4

The aim of this paper is to describe the development of the electron-beam optic analysis algorithm for simulating the e-beam behavior concerned with electrostatic lenses and their focal properties in the micro-column of the multi-beam lithography system. The electrostatic lens consists of an array of electrodes held at different potentials. The electrostatic lens, the so-called einzel lens, which is composed of three electrodes, is used to focus the electron beam by adjusting the voltages of the electrodes. The optics of an electron beam penetrating a region of an electric field is similar to the situation in light optics. The electron is accelerated or decelerated, and the trajectory depends on the angle of incidence with respect to the equi-potential surfaces of the field. The performance parameters, such as the working distances and the beam diameters are obtained by the computational simulations as a function of the focusing voltages of the einzel lens electrodes. Based on the developed simulation algorithm, the high performance of the micro-column can be achieved through optimized control of the einzel lens.

나노사출성형용 스탬퍼 제작을 위한 Electron beam lithography 패터닝 연구

엄상진(S.J. Uhm),서영호(Y.H. Seo),유영은(Y.E. Yoo),최두선(D-S. Choi),제태진(T.J. Je),황경현(K-H. Whang) 한국정밀공학회 2005 한국정밀공학회 학술발표대회 논문집 Vol.2005 No.10월

We have investigated experimentally a nano patterning using electron beam lithography for the nickel stamper fabrication. Recently, DVD and Blu-ray disk(BD) have nano-scale patterns in order to increase the storage density. Specially, BD has 100㎚-scale patterns which are generally fabricated by electron beam lithography. In this paper, we found optimum condition of electron-beam lithography for 100㎚-scale patterning. We controlled various conditions of EHP(acceleration voltage), beam current, dose and aperture size in order to obtain optimum conditions.We used 100㎚-thick PMMA layer on a silicon wafer as photoresist. We found that EHP was the most dominant factor in electron-beam lithography.

마이크로 칼럼의 전자 방출원 위치 오차의 영향

이응기,Lee, Eung-Ki 한국반도체디스플레이기술학회 2010 반도체디스플레이기술학회지 Vol.9 No.1

Currently miniaturized electron-optical columns find their way into electron beam lithography systems. For better lithography process, it is required to make smaller spot size and longer working distance. But, the micro-columns of the multi-beam lithography system suffer from chromatic and spherical aberration, even when the electron beam is exactly on the symmetric axis of the micro-column. The off-axis error of the electron emitting source is expected to become worse with increasing off-axis distance of the focusing spot. Especially the electron beams far from the system optical axis have a non-negligible asymmetric intensity distribution in the micro-column. In this paper, the effect of the off-axis e-beam source is analyzed. To analyze this effect is to introduce a micro-column model of which the e-beam emitting source is aligned with the center of the electron beam by shifting them perpendicular to the system optical axis. The presented solution can be used to analysis the performance of the multi-electron-beam system. The performance parameters, such as the working distances and the focusing position are obtained by the computational simulations as a function of the off-axis distance of the emitting source.

Direct Patterning of Self Assembled Nano-Structures of Block Copolymers via Electron Beam Lithography

Yoon Bo Kyung,Hwang Wonseok,Park Youn Jung,Hwang Jiyoung,Park Cheolmin,Chang Joonyeon The Polymer Society of Korea 2005 Macromolecular Research Vol.13 No.5

This study describes a method where the match of two different length scales, i.e., the patterns from self-assembled block copolymer (<50 nm) and electron beam writing (>50 nm), allow the nanometer scale pattern mask. The method is based on using block copolymers containing a poly(methyl methacrylate) (PMMA) block, which is subject to be decomposed under an electron beam, as a pattern resist for electron beam lithography. Electron beam on self assembled block copolymer thin film selectively etches PMMA microdomains, giving rise to a polymeric nano-pattern mask on which subsequent evaporation of chromium produces the arrays of Cr nanoparticles followed by lifting off the mask. Furthermore, electron beam lithography was performed on the micropatterned block copolymer film fabricated by micro-imprinting, leading to a hierarchical self assembled pattern where a broad range of length scales was effectively assembled, ranging from several tens of nanometers, through submicrons, to a few microns.

Direct Patterning of Self Assembled Nano-Structures of Block Copolymers via Electron Beam Lithography

윤보경,황원석,박철민,황지영,박연정,장준연 한국고분자학회 2005 Macromolecular Research Vol.13 No.5

This study describes a method where the match of two different length scales, i.e., the patterns from self-assembled block copolymer (<50nm) and electron beam writing (>50nm), allow the nanometer scale pattern mask. The method is based on using block copolymers containing a poly(methyl methacrylate) (PMMA) block, which is subject to be decomposed under an electron beam, as a pattern resist for electron beam lithography. Electron beam on self assembled block copolymer thin film selectively etches PMMA microdomains, giving rise to a polymeric nano pattern mask on which subsequent evaporation of chromium produces the arrays of Cr nanoparticles followed by lifting off the mask. Furthermore, electron beam lithography was performed on the micropatterned block copolymer film fabricated by micro-imprinting, leading to a hierarchical self assembled pattern where a broad range of length scales was effectively assembled, ranging from several tens of nanometers, through submicrons, to a few microns.

밀리미터파용 HEMT 소자 개발 및 제작을 위한 T-게이트 형성 전자빔 리소그래피 공정 모의 실험기 개발

손명식,김성찬,신동훈,이진구,황호정 대한전자공학회 2004 電子工學會論文誌-SD (Semiconductor and devices) Vol.41 No.5

밀리미터파 대역용 고속 HEMT 소자 제작 및 개발을 위하여 0.l㎛ 이하의 T-게이트 길이를 형성하기 위한 전자빔 리소그래피 공정을 분석할 수 있는 새로운 몬테 카를로 시뮬레이터를 개발하였다. 전자빔에 의한 노광 공정 모델링을 위해 전자산란에 대한 몬데 카를로 시뮬레이션에서 다층 리지스트 및 다원자 타겟 기판 구조에서 리지스트에 전이되는 에너지를 효율적으로 계산하도록 내부 쉘 전자 산란과 에너지 손실에 대해 새로이 모델링하였다. 다층 리지스트 구조에서 T-게이트 형상을 얻기 위해서 보통은 재현성 문제로 각 리지스트에 대해 각기 다른 현상액을 사용하게 되는데, 3층 리지스트 구조에서의 전자빔 리소그래피 공정을 정확하게 시뮬레이션하기 위해 각기 다른 현상 모델을 적용하였다. 본 논문에서 제안 개발된 모델을 사용하여 HEMT 소자의 전자빔 리소그래피에 의한 0.l㎛ T-게이트 형성 공정을 시뮬레이션하고 SEM 측정 결과와 비교하여 T-게이트 형성 공정을 분석하였다. A computationally efficient and accurate Monte Carlo (MC) simulator of electron beam lithography process has been developed for sub-0.l${\mu}{\textrm}{m}$ T-shaped gate formation in the HEMT devices for millimeter-wave frequencies. For the exposure process by electron to we newly and efficiently modeled the inner-shell electron scattering and its discrete energy loss with an incident electron for multi-layer resists and heterogeneous multi-layer targets in the MC simulation. In order to form the T-gate shape in resist layers, we usually use the different developer for each resist layer to obtain good reproducibility in the fabrication of HEMT devices. To model accurately the real fabrication process of electron beam lithography, we have applied the different developers in trilayer resist system By using this model we have simulated and analyzed 0.l${\mu}{\textrm}{m}$ T-gate fabrication process in the HEMT devices, and showed our simulation results with the SEM observations of the T-shaped gate process.

전자빔 리소그래피에서의 근접효과 보정

오세규(Se Kyu Oh),김승재(Seoung Jae Kim),정광오(Kwang Oh Jung),김동환(Dong Hwan Kim) 한국생산제조학회 2009 한국생산제조시스템학회 학술발표대회 논문집 Vol.2009 No.5

This study describes the proximity effect correction in an electron beam lithography. When the electron beam exposes into the resist, the beam tends to spread inside the substance (forward scattering), and to be reflected from substrate spreads (back scattering). These two effects of this electrons causes the distortion in the distribution of the energy, it is called a proximity effect. To compensate the effect, a dose control and added beam method are investigated, resulting in less proximity effect on the pattern with enhanced shapes.

Monte Carlo 수치해석법을 이용한 PMMA resist에서의 저 에너지 전자빔 투과 깊이에 관한 연구

안승준(Ahn Seung-Joon),안성준(Ahn Seong-Joon),김호섭(Kim, Ho-Seob) 한국산학기술학회 2007 한국산학기술학회논문지 Vol.8 No.4

반도체 소자 제작에 있어서 회로의 pattern 형성에 이용하는 차세대 lithography 공정 기술을 위해서 전자빔 lithography 공정 기술 연구가 진행되고 있다. 본 연구에서는 Gauss 해석법과 Monte Carlo의 수치해석법을 사용하여 두께 100 ㎚의 PMMA -(poly-methyl-methacrlatc) resist에 전자 1×10⁴개를 입사시키고, 입사 전자빔 에너지에 따른 PMMA 내에서의 투과 깊이를 비교하였다. 전자빔 에너지의 크기는 100eV, 300eV, 500eV, 700eV, 그리고 1000eV에 대하여 simulation을 실시하였다. There has been steady effort for the development of the electron-beam lithography technologies for the circuit patterning of the future semiconductor devices. In this study, we have performed a Monte-Carlo simulation where 1×10⁴ electrons with various kinetic energies (100eV, 300eV, 500eV, 700eV, and 1000eV) were shot into polymethyl methacrylate(PMMA) resist of 100-㎚ thickness. The penetration depth of each electron beam in the resist layer were analyzed using Gaussian analysis method.

전자빔 리소그래피에서의 근접효과 보정

오세규,김승재,정광오,김동환 한국공작기계학회 2009 한국공작기계학회 춘계학술대회논문집 Vol.2009 No.-

This study describes the proximity effect correction in an electron beam lithography. When the electron beam exposes into the resist, the beam tends to spread inside the substance (forward scattering), and to be reflected from substrate spreads (back scattering). These two effects of this electrons causes the distortion in the distribution of the energy, it is called a proximity effect. To compensate the effect, a dose control and added beam method are investigated, resulting in less proximity effect on the pattern with enhanced shapes.

ZEP520 포토리지스트를 이용한 나노 패턴 형성을 위한 전자빔 리소그래피 공정 모델링 및 시뮬레이션

손명식,Son, Myung-Sik 한국반도체디스플레이기술학회 2007 반도체디스플레이기술학회지 Vol.6 No.3

A computationally efficient and accurate Monte Carlo (MC) simulator of electron beam lithography process, which is named SCNU-EBL, has been developed for semiconductor nanometer pattern design and fabrication. The simulator is composed of a MC simulation model of electron trajectory into solid targets, an Gaussian-beam exposure simulation model, and a development simulation model of photoresist using a string model. Especially for the trajectories of incident electrons into the solid targets, the inner-shell electron scattering of an target atom and its discrete energy loss with an incident electron is efficiently modeled for multi-layer resists and heterogeneous multi-layer targets. The simulator was newly applied to the development profile simulation of ZEP520 positive photoresist for NGL(Next-Generation Lithography). The simulation of ZEP520 for electron-beam nanolithography gave a reasonable agreement with the SEM experiments of ZEP520 photoresist.