Analysis of Ion-Induced SEFI and SEL Phenomena in 90 nm NOR Flash Memory

Abstract

This article mainly focuses on the single event function interruption (SEFI) and single event latch-up (SEL) of 90 nm NOR flash memories. Devices were irradiated by ions with different linear energy transfer (LET) values from 12.9 to $65.8~MeV\cdot cm^{2}$ /mg. SEFI observed in the device is further divided into bit SEFI, column SEFI, and sector SEFI by severity of data corruption. Under irradiation with low LET value ions, SEL propagation-like phenomena were observed in this work, which was recognized as the process from local latch-up to global latch-up in the peripheral circuits. The underlying mechanisms for SEFI and SEL in NOR flash are discussed. Results indicate that the radiation-induced transient current should be responsible for SEFI, and different forms of SEFI depend on in which part of the circuit that transient current occurred. Besides, SEL in NOR flash is considered to be triggered from the peripheral circuits.