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Sn-xAg-0.5Cu 무연 솔더의 파손특성에 관한 실험적 연구
정종설,이용성,신기훈,정성균,김종형,장동영,Jeong, Jong-Seol,Lee, Yong-Sung,Shin, Ki-Hoon,Cheong, Seong-Kyun,Kim, Jong-Hyeong,Jang, Dong-Young 한국생산제조학회 2009 한국생산제조학회지 Vol.25 No.1
This paper presents an experimental study on the failure characteristics of SnAgCu lead-free solder balls. To estimate the effect of Ag, three types of SnAgCu balls are first prepared by varying the weight percent of Ag(1.0, 3.0, 4.0 wt%) and then analyzed by reliability tests such as thermal shock, high speed ball shear, and drop tests. Thermal shock test reveals that the higher the weight percent of Ag is, the longer the fatigue lift becomes. To the contrary, high speed ball-shear test and drop test show that the shear strength and the fracture toughness of solder balls are inversely proportional to the weight percent of Ag, respectively, Reasons for these observations will be further investigated In the future work.
서브 마이크로 구조를 가진 실리콘 표면의 마찰 특성 연구
한지희(Ji-Hee Han),한규범(Gue-Bum Han),장동영(Dong-Yong Jang),안효석(Hyo-Sok Ahn) 한국트라이볼로지학회 2017 한국트라이볼로지학회지 (Tribol. Lubr.) Vol.33 No.3
The understanding of the friction characteristics of micro-textured surface is of great importance to enhance the tribological properties of nano- and micro-devices. We fabricate rectangular patterns with submicron-scale structures on a Si wafer surface with various pitches and heights by using a focused ion beam (FIB). In addition, we fabricate tilted rectangular patterns to identify the influence of the tilt angle (45° and 135°) on friction behaviour. We perform the friction test using lateral force microscopy (LFM) employing a colloidal probe. We fabricate the colloidal probe by attaching a 10±1-μm-diameter borosilicate glass sphere to a tipless silicon cantilever by using a ultraviolet cure adhesive. The applied normal loads range between 200 nN and 1100 nN and the sliding speed was set to 12 μm/s. The test results show that the friction behavior varied depending on the pitch, height, and tilt angle of the microstructure. The friction forces were relatively lower for narrower and deeper pitches. The comparison of friction force between the sub-micro-structured surfaces and the original Si surface indicate an improvement of the friction property at a low load range. The current study provides a better understanding of the influence of pitch, height, and tilt angle of the microstructure on their tribological properties, enabling the design of sub-micro- and micro-structured Si surfaces to improve their mechanical durability.
정종설,이용성,신기훈,정성균,장동영 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-
This paper presents a study on the failure characteristics of SnAgCu lead-free solder balls. To estimate the effect of Ag, three types of SnAgCu balls are first prepared by varying the weight percent of Ag (1.0, 3.0, 4.0 wt%) and then analyzed by reliability tests such as thermal shock, high speed ball shear, and drop tests. Thermal shock test reveals that the higher the weight percent of Ag is, the longer the fatigue life becomes. To the contrary, high speed ball-shear test and drop test show that the shear strength and the fracture toughness of solder balls are inversely proportional to the weight percent of Ag, respectively. Reasons for these observations will be further investigated in the future work.