H.S. Kim

Publications (2)1.36 Total impact

• Conference Proceeding: Highly Scalable Phase Change Memory with CVD GeSbTe for Sub 50nm Generation

  J.I. Lee, H. Park, S.L. Cho, Y.L. Park, B.J. Bae, J.H. Park, J.S. Park, H.G. An, J.S. Bae, D.H. Ahn, Y.T. Kim, H. Horii, S.A. Song, J.C. Shin, S.O. Park, H.S. Kim, U-In Chung, J.T. Moon, B.I. Ryu
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  ABSTRACT: first present a PRAM with confinement of chemically vapor deposited GeSbTe (CVD GST) within high aspect ratio 50 nm contact for sub 50 nm generation PRAMs. By adopting confined GST, we were able to reduce the reset current below ~260 muA and thermally stable CVD Ge₂Sb₂Te₅ compound having hexagonal phase was uniformly filled in a contact while maintaining constant composition along with 150 nm depth. Our results indicate that the confined cell structure of 50 nm contact is applicable to PRAM device below 50 nm design rule due to small GST size based on small contact and direct top electrode contact, reduced reset current, minimized etch damage, and low thermal disturbance effect.
  VLSI Technology, 2007 IEEE Symposium on; 07/2007
• Article: Development of magnetic tunnel junction for toggle MRAM

  H.-J. Kim, S.C. Oh, J.S. Bae, K.T. Nam, J.E. Lee, S.O. Park, H.S. Kim, N.I. Lee, U-In Chung, J.T. Moon, H.K. Kang
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  ABSTRACT: Toggle switching mode MRAM is tested and characterized with respect to the free- and pinned-layer material and thickness. With magnetization curves, we were able to find the optimum thickness combinations of free-layer and spacer materials. For CoFeB where the intrinsic anisotropy field ( Hi) is about 20-30 Oe, one needs to have a reasonably high exchange coupling field (Hex) to ensure large switching margin. In case of an NiFe/Ru/NiFe free-layer, Hi is usually much smaller than Hex, so that further decrease of Hex between two magnetic layers is needed. The pinned-layer roughness and thickness are other factors to be optimized to reduce the toggle switching field. High cell aspect ratio ≥3.0 helps to minimize the switching distribution and enhance the switching stability.
  IEEE Transactions on Magnetics 11/2005; · 1.36 Impact Factor