Quantum confinement effect for efficient hole injection in MONOS-type nonvolatile memory-the role of ultrathin i-Si/P+ poly-Si stacked gate structure fabricated by laser spike annealing

A novel hole injection method is proposed for fast and damage-free erasing operation in MONOS-type nonvolatile memory. Ultrathin intrinsic Si (i-Si) layer at the interface between gate dielectrics and P+ poly-Si gate produces quantum confinement level of hole. This lowers effective band offset, thus, significantly increases hole tunneling probability from the gate electrode. By applying the novel gate structure to MONOS cells, we successfully demonstrate memory operation with 100 times faster erase speed and larger memory window than conventional gate.