"Instant On" Semiconductor Memories: Reality or Myth

Occasionally a device may conform to all parametric and functional tests required to meet its specification, however, due to certain critical performance characteristics the same device may fail in a system environment. One such problem exhibited by certain semiconductor memory devices is that of "Instant On", (commonly referred to as "Cold Start"). Instant On means that a device can be cooled down to its minimum operating temperature without power applied, then be powered up and function properly without any warmup cycles or operations. Some memory devices have been tested which do not meet this criteria. The sequential testing procedures implemented to isolate the critical time/temperature dependent characteristic will be described. The cause of failure will be identified and a proposed standard electrical test method to screen devices susceptible to these faults will be discussed.