Identification of Interface States and Shallow and Deep Hole Traps under NBTI Stress using Fast, Normal, and Charge-pumping Measurement Techniques

Abstract

We propose an identification method of interface state density (NSUBit/SUB), shallow hole trap density (NSUBht.S/SUB), and deep hole trap density (NSUBht.D/SUB), which were generated by negative bias temperature instability (NBTI) stress. NSUBht.S/SUB, NSUBht.D/SUB, and Nit were decoupled into recoverable traps and permanent traps through the proposed method. We analyzed which traps among hole-trapping charges and interface states constitute the main permanent damage component and have the largest power-law exponent with various stress voltages and temperatures. The power-law exponent of each trap showed that NSUBht.D/SUB and NSUBit/SUB lead to considerable timedependent degradation. Moreover, based on the recovery characteristics of each trap, 31% of the total traps became permanent traps and 77% of the permanent traps were NSUBht.D/SUB, which implies that NSUBht.D/SUB is a crucial factor, constituting the main component of the permanent damage.