Electronic structure of memory traps in silicon nitride

Native defects in hexagonalβ-Si3N4Grillo1, Elliott2, Freysoldt3 2011Phys. Rev. B363120View full textAdd to dashboardCite

“…1) above the VB edge of the unsaturated Si dangling bonds on N vacancies. This result is at odds with the predictions made by previous DFT studies, 7,8,20 which proposed hydrogenated Si dangling bond as the main source for memory traps in silicon nitride memories. None of these studies, however, calculated relative Si-rich defect formation energies that allow relative defect concentrations to be assessed.…”

“…11 Large amounts of hydrogen are present in silicon nitride sample production. 7,8 The role of hydrogen in the formation of local point defects in hydrogenated films a-SiN x :H was considered by calculating all possible H-saturated Si-rich defects. The chemical potential of hydrogen in the gas phase (μ H ) thereby used was calculated using statistical thermody-TABLE II.…”

“…1 These traps have been attributed to different types of silicon dangling bonds, termed K-center defects, based on electron spin resonance (ESR) measurements, [1][2][3][4] and electronic structure calculations of some native defects. [5][6][7][8] However, a comprehensive characterization of the atomic and electronic structure of e − and h + traps in silicon nitride is still missing. Yet, in order to optimize the efficiency of silicon nitrides for application in nonvolatile memories, it is crucial to understand the charge trapping mechanism of the intrinsic defects.…”

Impacts of conduction band offset and border traps on Vth instability of gate recessed normally-off GaN MIS-HEMTs

“…On the other hand, border traps are the defects inside the dielectric (not at the interface), and there are several models of the electron traps in silicon nitride [17]. Some of these bulk traps in the SiN x gate insulator which is located close to the interface could act as border traps.…”

Characterization of oxygen impurity in silicon nitride storage layer: A first-principles investigation

“…Intrinsic defects in silicon nitride have been studied experimentally and theoretically. Robertson and Powell have calculated the local density of states by tight‐binding recursion method; Gritsenko et al have studied the trapping of electrons and holes by using photoluminescence experiments and quantum‐chemical simulations; Vianello et al have investigated the trapping properties of standard and Si‐rich Si 3 N 4 samples; Valentin et al have explored the transition levels of intrinsic defects in Si 3 N 4 . In conventional fabrication processes, the pile of hydrogens and oxygens in the Si 3 N 4 layer has been observed experimentally .…”