Search | Korea Science

Higgs III, C. Fred;Ng, Sum Huan;Zhou, Chunhong;Yoon, In-Ho;Hight, Robert;Zhou, Zhiping;Yap, LipKong;Danyluk, Steven
- Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
- /
- 2002.10b
- /
- pp.441-442
- /
- 2002
Chemical mechanical polishing (CMP) is a manufacturing process that uses controlled wear to planarize dielectric and metallic layers on silicon wafers. CMP experiments revealed that a sub-ambient film pressure developed at the wafer/pad interface. Additionally, dishing occurs in CMP processes when the copper-in-trench lines are removed at a rate higher than the barrier layer. In order to study dishing across a stationary wafer during polishing, dishing maps were created. Since dishing is a function of the total contact pressure resulting from the applied load and the fluid pressure, the hydrodynamic pressure model was refined and used in an existing model to study copper dishing. Density maps, highlighting varying levels of dishing across the wafer face at different radial positions, were developed. This work will present the results.
PDF

Yoon, In-Ho;Ng, Sum Huan;Hight, Robert;Zhou, Chunhong;Higgs III, C. Fred;Yao, Lily;Danyluk, Steven
- Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
- /
- 2002.10b
- /
- pp.435-437
- /
- 2002
Polishing of copper, a process called copper chemical mechanical polishing, is a critical, intermediate step in the planarization of silicon wafers. During polishing, the electrodeposited copper films are removed by slurries: and the differential polishing rates between copper and the surrounding silicon dioxide leads to a greater removal of the copper. The differential polishing develops dimples and furrows; and the process is called dishing and erosion. In this work, we present the results of experiments on dishing and erosion of copper-CMP, using patterned silicon wafers. Results are analyzed for the pattern factors and properties of the copper layers. Three types of pads - plain, perforated, and grooved - were used for polishing. The effect of slurry chemistries and pad soaking is also reported.
PDF

Kim, Ii-Kwon;Kingsley Nickolas;Morton Matthew A.;Pinel Stephane;Papapolymerou John;Tentzeris Manos M.;Laskar Joy;Yook, Jong-Gwan
- Journal of electromagnetic engineering and science
- /
- v.6 no.4
- /
- pp.235-243
- /
- 2006
In this paper, the fractal shape is applied to microstrip band pass filters and integrated on a high-resistivity Si substrate to solve conventional $2^{nd}$ harmonic problem. Conventional microstrip coupled line filters are popular in RF front ends, because they can be easily fabricated and integrated with other RF components. However, they typically have large second harmonics that can cause unwanted interference in interested frequency bands. Without any additional filters, the proposed Koch shape filters have suppressed the $2^{nd}$ harmonics by about -40 dB, so they can be used in systems such as direct conversion receiver with stringent harmonic suppression requirements.
PDF KSCI

Seong, Jeong-C.;Dodge, Rebecca L.
- Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
- /
- 2009.04a
- /
- pp.138-141
- /
- 2009
This paper introduces AmericaView, a consortium for promoting remote sensing education, research and applications. As a case study, GeorgiaView is described in more detail. The AmericaView Consortium and StateView Consortia are good examples of collaboration for broadening the horizon of remote sensing applications in South Korea. Furthermore, the AmericaView example represents an opportunity for building a stepping stone to international collaboration.
PDF