FeRAM retention analysis method based on memory cell read signal voltage measurement

A retention analysis method for ferroelectric random access memory (FeRAM) was developed, in which read signal voltages from memory cells are measured. The method uses on-chip sample/hold circuits, an off-chip A/D converter, and memory large-scale integration testing equipment. FeRAM chip retention lifetime can be estimated on the basis of FeRAM read signal voltages after retention periods of one day and upwards. When used as a tool to estimate long-term data retention in FeRAM chips and to analyze fluctuations in memory cell characteristics, this method can provide useful information about FeRAM reliability.