Ge ∕ Si heteronanocrystal floating gate memory

Metal oxide semiconductor field effect transistor memories with Ge∕Si heteronanocrystals (HNCs) as floating gate were fabricated and characterized. Ge∕Si HNCs with density of 5×1011cm−2 were grown on n-type Si (100) substrate with thin tunnel oxide on the top. Enhanced device performances including longer retention time, faster programming speed, and higher charge storage capability are demonstrated compared with Si nanocrystal (NC) memories. The erasing speed and endurance performance of Ge∕Si HNC memories are similar to that of Si NC devices. The results suggest that Ge∕Si HNCs may be an alternative to make further floating gate memory scaling down possible.