Simulation of BTI-Related Time-Dependent Variability in CMOS Circuits

On the Structure of Oxygen Deficient Amorphous Oxide Films

“…[ 53 ] Electron and hole trapping by defects and transport through defects in oxide films are the origin of many phenomena plaguing the performance of devices, such as film charging, random telegraph noise, bias temperature instability, and dielectric breakdown. [ 14,15 ] In these processes, electrons (holes) are transferred to/from electrodes changing the defect charge state. Hence, the ability of defects in amorphous films to reversibly trap/detrap electrons is a fundamental property at the center of device performance and reliability.…”

“…Electrical measurements of current through oxide films or changes in capacitance are extremely sensitive and can detect even single-electron processes. [15] However, unambiguously establishing the nature and atomistic structures of the electron traps responsible for these processes can be very complex. [15,53] The difficulty of experimental characterization of amorphous oxide films and the increased power of computation lead to a heavy reliance on atomistic simulations to understand defects in amorphous oxides and to predict their behavior.…”

“…[15] However, unambiguously establishing the nature and atomistic structures of the electron traps responsible for these processes can be very complex. [15,53] The difficulty of experimental characterization of amorphous oxide films and the increased power of computation lead to a heavy reliance on atomistic simulations to understand defects in amorphous oxides and to predict their behavior. Many of such simulations involve significant approximations, and linking their predictions with experimental observations is often a challenge.…”

“…[ 14,19,50,51 ] However, the amount of experimental data characterizing point defects in amorphous oxide films is limited, and the available data are much less detailed than in the case of bulk crystals. [ 6,15,52 ] Therefore, the properties of these defects and their atomic structures are very difficult to establish experimentally using techniques effective in bulk crystals because their sensitivities (e.g., optical absorption, EPR, EXAFS, etc.) are not sufficient to probe defect properties in nanometer‐thin films used in many devices.…”

“…[ 12,13 ] Their performance in electronic devices is affected by electrical and structural degradation, attributed to their metastable nature, as well as to pre‐existing and generated point defects. [ 6,14 ] Among these defects, oxygen vacancies are routinely alleged to cause many effects degrading the performance of electronic devices (e.g., field effect transistors and memory cells) [ 14,15 ] often by analogy with crystals. However, the nature and structure of even these basic defects in amorphous oxides remain poorly understood due to the absence of long‐range order and variations in local order.…”