TDDB in HfSiON/SiO2 dielectric stack: Büttiker probe based NEGF modeling, prediction and experiment

• Main Authors: Reza, Ahmed Kamal, Hassan, Mohammad Khaled, Roy, Kaushik, Patra, Devyani, Bansal, Ankita, Yu Cao
• Format: Conference Proceeding
• Language: English
• Subjects: Breakdown Prediction; Büttiker probe; Dielectrics; Electric breakdown; HfSiON; high-κ metal gate (HKMG); Logic gates; Non-equilibrium Green's function (NEGF); Probes; Stress; Stress Induced Leakage Current (SILC); Temperature; Temperature Stress; Time dependent Dielectric Breakdown (TDDB); Tunneling; Voltage Stress; Weibull
• ISSN: 1938-1891
• DOI: 10.1109/IRPS.2017.7936362

HfO2 based high-κ metal gate (HKMG) transistors offer low leakage current and high integration density. However, they are vulnerable to defect formation. In this paper, we have demonstrated a Büttiker probe based leakage current model [1][2] for determining the gate leakage current in a HKMG transistor due to defects in the gate dielectric layer. These defects can be pre-existing defects (PEDs) as well as the stress induced defects in the gate dielectric stack. The model was also used to determine the post breakdown gate current characteristics. We have verified our model with experimentally measured data from 28nm planar devices with HfSiON/SiO 2 gate dielectric layer. In addition, we have integrated the Büttiker probe method and percolation model [3] to predict the time to failure (t BD ) of the device. The proposed simulation methodology can also be used to determine the required stress condition (SC) to observe breakdown in a device within a certain period of time.