Patent ID: 7019545

Claim:
A method for fast monitoring the stress-induced degradation of an insulation layer in a capacitor by a wafer acceptance testing (WAT) equipment, the method comprising: (a) providing a substrate, a surface of the substrate comprising a first conductive layer, a second conductive layer, and the insulation layer disposed between the first conductive layer and the second conductive layer; (b) applying a first voltage to the first conductive layer, the first voltage being a swing time-dependent DC ramping voltage; (c) measuring a first leakage current flowing through the first conductive layer to calculate a first proportional value from the first voltage, the first leakage current, and an equation, the first proportional value corresponding to the first voltage; (d) applying a second voltage to the first conductive layer, the second voltage being a swing time-dependent DC ramping voltage; (e) measuring a second leakage current flowing through the first conductive layer to calculate a second proportional value from the second voltage, the second leakage current, and the equation, the second proportional value corresponding to the second voltage; and (f) calculating a first ratio of the second proportional value to the first proportional value.