Advanced Extraction of Trap Parameters from Single-Defect Measurements

Abstract

Charge trapping at oxide defects is a serious reliability concern in MOS transistors. For scaled technology nodes, the impact of charge-trapping events on the device behavior becomes even more severe. It can be observed as discrete steps in the device current, enabling single-defect analysis. In this context, the analysis of random telegraph noise (RTN) and time-dependent defect spectroscopy (TDDS) have become very popular in exploring the physical origin of charge trapping at single defects. To improve the accuracy of the single-defect analysis, we perform a Monte Carlo analysis of the trap occupancy that enables us to extract information about the charge emission time of fixed oxide traps from charge capture time data recorded at stress conditions. The newly gained knowledge is beneficial for accurately calibrating defect models used to explain the charge-trapping dynamics of the defects. Furthermore, the additional data support the verification of the extrapolation from trapping models and help to improve the quality of the extracted trap level, trap depth, and energy barriers.