Kabseog Kim
University of Texas at Dallas
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Kabseog Kim.
Journal of Micromechanics and Microengineering | 2004
Kabseog Kim; Daniel S. Park; Hong M. Lu; Wooseong Che; Kyunghwan Kim; Jeong Bong Lee; Chong H. Ahn
This paper presents a novel fabrication process for a tapered hollow metallic microneedle array using backside exposure of SU-8, and analytic solutions of critical buckling of a tapered hollow microneedle. An SU-8 mesa was formed on a Pyrex glass substrate and another SU-8 layer, which was spun on top of the SU-8 mesa, was exposed through the backside of the glass substrate. An array of SU-8 tapered pillar structures, with angles in the range of 3.1 ◦ –5 ◦ , was formed on top of the SU-8 mesa. Conformal electrodeposition of metal was carried out followed by a mechanical polishing using a planarizing polymeric layer. All organic layers were then removed to create a metallic hollow microneedle array with a fluidic reservoir on the backside. Both 200 µm and 400 µm tall, 10 by 10 arrays of metallic microneedles with inner diameters of the tip in the range of 33.6–101 µm and wall thickness of 10–20 µm were fabricated. Analytic solutions of the critical buckling of arbitrary-angled truncated cone-shaped columns are also presented. It was found that a single 400 µm tall hollow cylindrical microneedle made of electroplated nickel with a wall thickness of 20 µm, a tapered angle of 3.08 ◦ and a tip inner diameter of 33.6 µ mh as a critical buckling force of 1.8 N. This analytic solution can be used for square or rectangular cross-sectioned column structures with proper modifications.
Archive | 2001
Jin-Woo Choi; Sanghyo Kim; Hyoung J. Cho; Aniruddha Puntambekar; Robert Lawrence Cole; Jeffrey R. Simkins; Suresh Murugesan; Kabseog Kim; Jeong-Bong Lee; Gregory Beaucage; Joseph H. Nevin; Chong H. Ahn
This paper presents an innovative plastic micro injection molding technique using replaceable disk-mold for applications to microfluidic systems and biochips. Precisely patterned and microfabricated wafer-type mold inserts can be easily loaded into the injection molding machine. Processing time for one chip was as fast as 10 seconds while hot embossing techniques require at least several minutes. Less than a few urn of precise patterns were also achieved. A promising new material has also been introduced and characterized using the developed injection molding technique as well as demonstrated for a disposable biochip.
Journal of Micromechanics and Microengineering | 2004
Daniel Sang Won Park; Kabseog Kim; Brandon Pillans; Jeong Bong Lee
This paper presents a novel pattern transfer process of LIGA and UV-LIGA MEMS onto CMOS chips using polydimethylsiloxane (PDMS) replication and electroplating-based post-IC integration techniques. An array of cylindrical posts was fabricated by the standard LIGA process and an inverse replica was made using a PDMS replication technique. The replicated PDMS mold was used to transfer the LIGA MEMS onto a CMOS chip using electroplating. For the pattern transfer of UV-LIGA MEMS onto CMOS chips, double-layered circular spiral inductors were fabricated using the UV-LIGA technique as metallic master molds. Inverse replicas of the inductors were built in PDMS as double-layered PDMS electroplating mold (PEM). This PEM was aligned and attached onto the chips, and electroplating was performed to transfer the metallic UV-LIGA MEMS inductors onto the chips. The transferred inductors showed a self-resonant frequency of 7.5 GHz, an inductance of 2.11 nH, and a Q-factor of 78.9 at 0.6 GHz.
Proceedings of SPIE | 2003
Trent Huang; Erik Nilsen; Matt Ellis; Kabseog Kim; Ken Tsui; George D. Skidmore; Chuck Goldsmith; Arunkumar Nallani; Jeong Bong Lee
It is of great interest to develop an efficient and reliable manufacturing approach that allows for the integration of microdevices each of which is optimally fabricated using a different process. We present a new method to achieve electrical and mechanical interconnects for use in heterogeneous integration. This method combines metal reflow and a self-aligned, 3-D microassembly approach. The results obtained so far include a self-aligned, 3-D assembly of MEMS to MEMS, post-processing which selectively deposited indium on 50 μm-thick MEMS structures, and reflow tests of indium-on-gold samples demonstrating 15-45 mΩ resistances for contact areas ranging from 100 to 625 μm2. 3-D microassembly coupled with metal reflow allows for the batch processing of a large number of heterogeneous devices into one system without sacrificing performance. In addition, its 3-D nature adds a new degree of freedom in system design space. Downward scalability of the method is also discussed.
SPIE's 8th Annual International Symposium on Smart Structures and Materials | 2001
Sang Won Park; Kabseog Kim; Harish Manohara; Jeong-Bong Lee
This paper presents a rapid replication technique for polydimethylsiloxane (PDMS) high aspect ratio microstructures (HARMs) and a pattern transfer technique for replication of metallic HARMs on other substrates (such as circuit containing substrates) using such replicated PDMS HARMs. A high aspect ratio metallic micromold insert, featuring a variety of test microstructures made of electroplated nickel, has been fabricated by the standard deep X-ray lithography (DXRL) process. Mixed pre-polymer PDMS with a curing agent has been cast onto the metallic micromold insert test patterns to create replicated polymeric HARMs. The replicated PDMS HARMs could be used to massively reproduce high aspect ratio metallic microstructures on other substrates using a pattern transfer technique. In order to demonstrate the concept, an experiment has been carried out to attach the replicated PDMS HARMs onto a silicon substrate which has pre-deposited photoresist and metallic seed layer. Electrodeposition has been carried out through the attached PDMS HARMs mold followed by the subsequent removal of the PDMS, resulting in high aspect ratio metallic microstructures on the silicon substrate. This technique could be used to massively reproduce metallic HARMs on circuit containing substrates to create 3-D integrated MEMS devices.
Archive | 2004
Kabseog Kim; Jeong-Bong Lee
Microsystem Technologies-micro-and Nanosystems-information Storage and Processing Systems | 2002
Kabseog Kim; Sang Won Park; Jeong-Bong Lee; Harish M. Manohara; Yohannes M. Desta; Michael C. Murphy; Chong H. Ahn
Microsystem Technologies-micro-and Nanosystems-information Storage and Processing Systems | 2006
Kabseog Kim; Jeong Bong Lee
Archive | 2001
Jeong-Bong Lee; Harish M. Manohara; Kabseog Kim; Sang Won Park
Microsystem Technologies-micro-and Nanosystems-information Storage and Processing Systems | 2004
Kabseog Kim; E. Nilsen; T. Huang; A. Kim; Matthew D. Ellis; George D. Skidmore; Jeong Bong Lee