Failure mechanism

The initiating physical process which creates the failure mechanism.

A seminconductor memory failure mechanism. Nonvolatile memories are subject to several mechanisms that can cause data to be lost. For floating gate memories, a cell’s data (‘0’ or ‘1’) depends on whether its threshold voltage (VT ) is above or below a critical threshold level (VT,crit). The threshold voltage may shift over time, leading to a change in data. The most common mechanisms for threshold drift are dielectric charge leakage and dielectric charge detrapping. (Reference JEP122F)

A failure mechanism in silicon based electronic devices. It describes the phenomenon by which carriers gain sufficient energy to be injected into the gate oxide. This occurs as carriers move along the channel in MOSFET and experience impact ionization near the drain end of the device. The damage can occur at the interface, within the oxide and/or within the sidewall spacer. Interface-state generation and charge trapping induced by this mechanism result in transistor parameter degradation, typically switching frequency degradation, rather than a “hard’ functional failure. (Reference JEP122F)

Subsequent to a failure, the logical systematic examination of an item, its construction, application, and documentation to identify the failure and determine the failure mechanism and its basic cause. FA provides the necessary information to identify suitable short-term and long-term solutions to avoid similar failures in the future.

1) an equivalent activation energy for use with complex structures (IC for example) to estimate the time to failure distribution. 2) a calculated activation energy using the relationship between stress and failure rate (empirically derived) representing the relationship between the applied stress and time-to-failure for a specific failure mechanism.