http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Slurry Temperature Effect on Copper CMP
Pengzhan Liu,SungHoon Bae,Seokjun Hong,Chulwoo Bae,Taesung Kim 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.5
During the process of chemical mechanical polishing, much heat was generated due to friction force between CMP pad and wafer. Wafer and pad surface temperature had a stepped upward trend with the beginning of polishing process. The effects on chemical reaction and mechanical mechanism were investigated separately. BTA was proved to be ineffective in high temperature slurry environment. Other chemical reaction such as corrosion and oxidation also accelerated. But temperature did not influence the slurry particle size. By using high temperature slurry, the polishing temperature conditions at the later stage could be achieved directly, and removal rate also increased correspondingly.
Pengzhan Liu,Guoqiang Wang,Zhen Yang,Xiongfei Zhao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.11
In the era of unmanned war, with the increasing muzzle velocity requirement, the design of gun is significantly restricted by recoil, especially for guns installed on unmanned aerial vehicles. A recoilless gun with combustible cartridge was designed to eliminate recoil and increase projectile velocity, and the influence of main parameters on recoil was studied. First, a design of a recoilless gun with high projectile velocity is proposed based on combustible cartridge case. Next, a classical interior ballistic model is developed during the recoilless gun firing cycle, and the effect of main parameters of interior ballistics on the performance is investigated. Additionally, simple nonlinear fitting formulae are defined to highlight the variation of recoil momentum with the time of interior ballistic model. Finally, numerical simulation results are compared with the test results to validate the feasibility of the design. The experimental results demonstrate that the classical interior ballistic model can be used to accurately analyze the effect of the parameters on the projectile velocity and the recoil reduction efficiency. The projectile velocity of the recoilless gun could raised to 1200 m/s and the recoil momentum could be eliminated almostly. Therefore, the newly designed recoilless gun effectively eliminates the recoil momentum and significantly improves the projectile velocity. The findings should make an important contribution to the field of engineering applications of recoilless gun.
전기적 저압 임팩터를 이용한 에피택셜 챔버 내 입자 측정 및 분석
이승재(Seung Jae Lee),김은미(Eun Mi Kim),Vinit Kanade,Pengzhan Liu,금승호(Seung Ho Keum),임홍강(Hong Kang Lim),김태성(Tae Sung Kim) 대한설비공학회 2020 대한설비공학회 학술발표대회논문집 Vol.2020 No.6
The purpose of this study was to measure and analyze the residual particles in the epitaxial growth chamber that can affect the process and the particles generated during the PM(preventive maintenance), which is the process of inspecting and replacing equipment parts. First, we devised a method using an ELPI(electric low pressure impactor) that can conduct real-time measurement of particle number, mass concentration and enable further analysis of chemical component by collecting the particles on the impactor substrates. Based on the result, it was confirmed that there are few particles in chamber before preventive maintenance and it is possible that amount of particles were generated or flowed from outside during the preventive maintenance work. Additionally, the components of the collected particles were analyzed through SEM-EDS analysis.