Transient 3-D TCAD simulation of multiple snapback event in mixed-mode test for mutual relation between protection devices

Mutual ESD behavior dependency between multiple devices under Transmission Line Pulse stress was investigated using transient 3-D TCAD simulation. Interestingly, the transient response of drain voltage has multiple snapback profiles in the mixed-mode test. When one of the devices in the mixed-mode test is turned on, the current waveform of the other adjacent devices shows snapback profile. This mutual relation between protection devices affects the ESD robustness. If there is a big imbalance of individual ESD characteristics between the devices under the mixed-mode test, the lattice temperature hot-spot and failure may occurs in the device even though the robustness of the other connected device is lower than that of the device in the single-device test.