• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 추계학술대회 논문집
• /
• pp.593-597
• /
• 2005

FIB equipment can perform sputtering and chemical vapor deposition simultaneously. It is very advantageously used to fabricate a micro structure part having 3D shape because the minimum beam size of ${\phi}$ 10nm and smaller is available. Currently FIB is not being applied in the fabrication of this micro part because of some problems to redeposition and charging effect of the substrate causing reduction of accuracy with regards to shape and productivity. Furthermore, the prediction of the material removal rate information should be required but it has been insufficient for micro part fabrication. The paper have the targets that are FIB-CVD characteristic analysis and minimum line pattern resolution achievement fur 3D micro fabrication. We make conclusions with the analysis of the results of the experiment according to beam current, pattern size and scanning parameters. CVD of 8 pico ampere shows superior CVD yield but CVD of 1318 pico ampere shows the pattern sputtered. And dwell time is dominant parameter relating to CVD yield.

• 한국음향학회지
• /
• 제39권1호
• /
• pp.16-23
• /
• 2020

고강도 집중 초음파(High-Intensity Focused Ultrasound, HIFU) 치료에서 HIFU 초점의 효과적인 위치 파악은 안전한 치료 계획을 개발하는 데 중요하다. 자기 공명 영상 유도 HIFU(Magnetic Resonance Imaging guided HIFU, MRIgHIFU)는 HIFU 초점을 영상화하여 치료 중에 초음파 경로를 시각화 할 수 있지만 초음파 이미징 유도 HIFU(Ultrasound imaging guided HIFU, USIgHIFU)에서는 어려움이 있다. 본 연구에서는 USIgHIFU에 대해 HIFU 초점을 영상화할 수 있는 실시간 초음파 빔 시각화 기법을 제시 하였다. 제안 된 방법에서, 음향 강도(Ispta < 720 mW/㎠) 아래의 이미징 초음파 변환자의 동일한 중심 주파수를 갖는 짧은 펄스가 HIFU 변환기를 통해 전송되고, HIFU 빔 경로를 시각화하기 위해 수신 신호는 동적 수신 포커싱 및 후속 에코 처리를 거쳤다. 소 혈청 알부민 젤 팬텀을 이용한 생체외 실험으로부터, HIFU 빔 경로는 낮은 음향 강도 (Ispta = 94.8 mW/㎠)에서도 명확히 영상화 할 수 있었고 HIFU 초점은 손상이 생성되기 전에 성공적으로 시각화하였다. 이 결과는 제안 된 초음파 빔 경로 시각화 방법이 USIgHIFU 치료에서 원치 않는 조직 손상을 최소화하면서 실시간으로 HIFU 초점을 영상화하는 데 사용될 수 있음을 나타낸다.

• 한국광학회지
• /
• 제31권6호
• /
• pp.268-273
• /
• 2020

레이저 빔이 산란 매질에서 반사될 때 발생하는 스펙클 패턴을 모니터링함으로써 산란 매질에 입사하는 레이저 빔들의 결맞는(coherent) 결합 상태를 분석하고자 하였다. 이를 위하여 가간섭성이 높은 3개의 시준 레이저 광원을 자유공간에서 렌즈를 이용하여 무작위 표면특성을 가진 산란목표물(scattering target)에 집속한 후, 되돌아오는 빔의 스펙클 패턴을 푸리에 영역에서 살펴보았다. 목표물에 입사하는 단일 레이저 빔의 크기변화 및 3개 결맞는 레이저 빔 간의 공간적인 빔결합 정도에 따라 스펙클 패턴의 평균적인 크기가 변하게 되는데, 이를 푸리에 영역에서 분석함으로써 결맞음 빔결합의 효율을 판별할 수 있는 단일 모니터링 변수를 도출할 수 있었다.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
• /
• pp.51-53
• /
• 2004

An analytical method is developed which focused on the end effects for determining the thermal stress distribution in an laminated beam bonded with adhesive layer. This method gives the stress distribution which satisfy the stress-free boundary condition at edge completely. Numerical example, in which an Al-Cu beam bonded with solder(Pb-Sn) is treated, shows that the shear and peeling stresses at the interfaces are significant near the edge and become negligible in the interior region.

• Rapid Communication in Photoscience
• /
• 제5권2호
• /
• pp.16-17
• /
• 2016

Arylalkyne cobalt complexes 5, 6 were prepared and irradiated with e-beam to study their fragmentation focused in alkyne formation. Thioaryl complex 6 showed facile CO ligand release and generated parent alkyne in 89% relative intensity. Meanwhile, hydroxyaryl complex 5 gave alkyne in 6% relative intensity.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2010년도 추계학술대회 논문집
• /
• pp.67-68
• /
• 2010

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
• /
• pp.806-809
• /
• 2003

Ion-induced secondary electron emission coefficient $({\gamma})$. of the patterned MgO thin film with geometrical structures has been measured by ${\gamma}$ - FIB(focused ion beam) system. The patterned MgO thin film with geometrical structures has been formed by the mask (mesh of ${\sim}$ $10{\mu}m^{2})$ under electron beam evaporation method. It is found that the higher ${\gamma}$. has been achieved by the patterned MgO thin film than the normal ones without patterning.

• 한국공작기계학회논문집
• /
• 제17권5호
• /
• pp.52-57
• /
• 2008

Most of the electrons emitted from the filament, are captured by the anode. The portion of the electron current that leaves the gun through the hole in the anode is called the beam current. Electron beam probe is called the focused beam on the specimen. Because of the lenes and aperture, the probe current becomes smaller than the beam current. It generate various signals(backscattered electron, secondary electron) in an interaction with the specimen atoms. Backscattered electron provide an useful signal for composition and local specimen surface inclination. Secondary electron is used far the formation of surface imagination. The steady electron beam probe is very important for the imagination formation and the brightness. In this paper, we show the results of developed elements that create electron beam probe and the measured beam probe in various acceleration voltages by Faraday cup. These data are used to analysis and improve the performance of the system in the development.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
• /
• pp.802-805
• /
• 2003

The ion-induced secondary electron emission coefficient ${\gamma}$ for MgO thin film with $O_{2}$ plasma treatment has been investigated by ${\gamma}$-FIB (focused ion beam) system. The MgO thin film deposited from sintered material with $O_2$ plasma treatment is found to have higher ${\gamma}$ than that without $O_{2}$ plasma treatment. The energy of $Ne^{+}$ ions used has been ranged from 100eV to 200eV throughout this experiment. It is found that the highest secondary electron emission coefficient ${\gamma}$ has been achieved for 10 minutes of $O_{2}$ plasma treatment.

• 반도체디스플레이기술학회지
• /
• 제18권1호
• /
• pp.38-41
• /
• 2019

Proton beam writing is a direct writing lithography technique for semiconductor fabrication process. The advantage of this technique is that the proton beam does not scatter as they travel through the matter and therefore maintain a straight path as they penetrate into the resist. The experiment has been carried out at Accelerator Mass Spectrometry facility. The focused proton beam with the fluence of $100nC/mm^2$ was exposed on the PMMA coated silicon sample to make a pattern on a photo resist. The results show the potential of proton beam writing as an effective way to produce semiconductor fabrication process.