Automated test equipment for research on nonvolatile memories

This paper presents a measurement system for research on nonvolatile memories, such as flash, EPROM, EEPROM. The instrument architecture is based on the PCI local bus, thus allowing a direct interface of the memory under test with the PC controlling the measurement. A rank of programmable waveform generators allows applying arbitrary signals to the memory cells during writing and reading, thus guaranteeing the flexibility required at the research level. The instrument performances have been evaluated on 4 MB test chips and results are comparable to those of commercial automated test equipment (ATE). This instrument, besides the analysis of writing operations, can be successfully used to evaluate the evolution of such operations during memory cycling and their impact on long-term reliability.