A method for rapid screening of various low-k TDDB models

Abstract

Voltage or Field acceleration model is crucial for low-k TDDB reliability study and lifetime projection. Over the years, many different acceleration models have been proposed based on different physics. In this paper, a method for a relatively fast screen of various low-k TDDB models is proposed. Fast voltage ramp test to establish a relation of JE slope versus stress field is the first step. Study of J-E slopes in advance before time-consuming TDDB could provide insight into TDDB kinetics. Next is to select appropriate stress voltages based on J-E characteristics with high density voltage points but at high and medium stress voltage ranges. Lastly, by proceeding with the local acceleration factor comparison and correlating it to J-E slope versus voltage relation, the most likely and the most unlikely models can effectively be determined within a much shorter period of stress time.