New convergence scheme to improve the endurance characteristics in flash memory

새로운 Convergence 방법을 이용한 플래시 메모리의 개서 특성 개선

  • 김한기 (인천대학교 전자공학과) ;
  • 천종렬 (인천대학교 전자공학과) ;
  • 이재기 (가천길대학교 전자통신과) ;
  • 유종근 (인천대학교 전자공학과) ;
  • 박종태 (인천대학교 전자공학과)
  • Published : 2000.06.01

Abstract

The electrons and holes trapped in the tunneling oxide and interface-states generated in the Si/SiO$_2$ interface during program/erase (P/E) operations are known to cause reliability problems which can deteriorate the cell performance and cause the V$_{th}$ window close. This deterioration is caused by the accumulation of electrons and holes trapped in the oxide near the drain and source side after each P/E cycle. we propose three new erase schemes to improve the cell's endurance characteristics: (1)adding a Reverse soft program cycle after the source erase operation, (2)adding a detrapping cycle after the source erase operation, (3)adding a convergence cycle after the source erase operation. (3) is the most effective performance among the three erase schemes have been implemented and shown to significantly reduce the V$_{th}$ window close problem. And we are able to design the reliable periperal circuit of flash memory by using the (3).(3).

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