INFLUENCE OF THE SERIES RESISTANCE OF ON-CHIP POWER-SUPPLY BUSES ON INTERNAL DEVICE FAILURE AFTER ESD STRESS

Bus wires of on-chip power supplies are resistive because of their lim ited width. During an ESD event, this resistance initiates a local int ernal over voltage through a high discharge current peak, which can ca use damage to internal source/drain areas. A detailed description of t he mechanism that causes this internal damage an a simple estimation o f the minimum width of power supply buses on semi-conductor devices is given. Additional protection circuits for improving the ESD resistivi ty against internal failure, are presented.