Characterization of reliability in 3-D NAND flash memory
Jong‐Ho Lee, Sung-Min Joe, Ho-Jung Kang · 2014
The trap density (Nt) in nitride storage layer is extracted in 3-D NAND flash memory cells with tube-type poly-Si body. We extract the Ntby utilizing AC-gmmethod and deriving related equations in cylindrical coordinate. The AC-gmmethod makes the Ntprofiling with distance from the interface possible. We also characterize the behavior of transient bit-line current (IBL) during reading after applying a pre-bias (Vpre). Depending on the dominance of charge trapping in blocking dielectric or at the interface between the tunneling oxide and poly-Si body, different behaviors of transient IBLare observed. To identify the cause, we systematically analyze the capture and emission of charges in different trap sites by investigating the behavior of transient IBLduring reading with various Vpres.