Patent attributes
In making a multi-bit memory cell, a first insulating layer is formed over a semiconductor substrate. A second insulating layer is formed over the first insulating layer. A layer of gate material is formed over the second insulating layer and patterned to leave a gate portion. The second insulating layer is etched to undercut the gate portion and leave a portion of the second insulating layer between the first insulating layer and the gate portion. Nanocrystals are formed on the first insulating layer. A first portion of the nanocrystals is under the gate portion on a first side of the portion of the second insulating layer and a second portion of the nanocrystals is under the gate portion on a second side of the portion of the second insulating layer. The first and second portions of the nanocrystals are for storing logic states of first and second bits, respectively.