평면구조 P-MOS DRAM 셀의 커패시터 VT 이온주입의 최적화

Optimization of Capacitor Threshold VT Implantation for Planar P-MOS DRAM Cell

  • 장성근 (청운대학교 디지털방송공학과) ;
  • 김윤장 (매그나칩 반도체 DSD소자 2팀)
  • 발행 : 2006.02.01


We investigated an optimized condition of the capacitor threshold voltage implantation(capacitor $V_T$ Implant) in planar P-MOS DRAM Cell. Several samples with different condition of the capacitor $V_T$ Implant were prepared. It appeared that for the capacitor $V_T$ Implant of $BF_2\;2.0{\times}l0^{13}\;cm^{-2}$ 15 KeV, refresh time is three times larger than that of the sample, in which capacitor $V_T$ Implant is in $BF_2\;1.0{\times}l0^{13}\;cm^{-2}$ 15 KeV. Raphael simulation revealed that the lowed maximum electric field and lowed minimum depletion capacitance ($C_{MIN}$) under the capacitor resulted in well refresh characteristics.


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