GATE OXIDE EVALUATIONS FROM HIGH-E TESTS

摘要

Recent published data show the complete pattern of defect failures, intrinsic failures and the transition region between them. This explains many earlier misinterpretations. It provides a life curve for intrinsic failures, extending far beyond observation times in most cases, using a plot of acceleration factors independent of the 1/E vs. E relationship controversy between 6MV/cm. Life is linear with 1/E at 6MV/cm and above. Estimates of defect densities are available from the transition region, and are capable of extrapolation from high-E life tests to low gradients of operation. At voltage gradients much below 6MV/cm, however, this extrapolation cannot be corroborated in the long straight line of the transition. A single point test can be performed at about the time to the inflection point at 8 or 9 MV/cm stress to serve as a quality control point for the oxide defect density. This transition life line, however, can be used to derive a plot of failure rate which can be used to define screening procedures.