Si3N4 based non-volatile memory structures with embedded Si and Ge nanocrystals

Memory structures with an embedded sheet of separated Si nanocrystals were prepared by low pressure chemical vapour deposition using a Si
₃
N
₄
control and SiO
₂
tunnel layers. It was obtained that a properly located layer of Si or Ge nanocrystals can improve both the charging and retention behaviour of the MNOS structures simultaneously. Memory window width of about 6.6 V and retention time of 41 years has been achieved for charging pulses of plusmn15 V, 10 m.s.