NPN Si/SiGe memory selector with non-linearity>105 and ON-current>6MA/cm2

This work reports on NPN Si/SiGe heterojunction bipolar latch-up memory selectors integrated in 300mm wafers. The selector height has been scaled down to sub-100nm dimensions. The Ge concentration is varied from 25% to 45%. The device obtained features an ON-current (I
ON
) in the negative branch above 6MA/cm
²
, and a non-linearity (NL) exceeding 10
⁵
hence meeting the STT-MRAM selector target specifications. Further, these selectors exhibit stable characteristics over 10
⁹
pulses.