Magnetic resonance observations of defects involved in bias temperature instabilities and stress induced leakage currents in hafnium dioxide and silicon dioxide based metal-oxide-silicon structures.

摘要

This study examines underlying physical mechanisms involved in two very important reliability problems in SiO2 based and HfO2 based metal-oxide-silicon technology: the negative bias temperature instability (NBTI) and an important aspect of low-voltage stress induced leakage currents (LV-SILC). A combination of conventional electron spin resonance (ESR), electrically-detected magnetic resonance including spin dependent recombination (SDR) and spin dependent tunneling (SDT), and electrical measurements have been utilized to study variously processed samples in an attempt to understand the specific defects and the roles that they play in these reliability problems.;After a brief introduction and background, chapter 3 discusses a newly developed means to perform SDT on ultra-thin oxides which we call energy-resolved spin dependent tunneling and is used to directly determine the energy levels of K centers involved in LV-SILC in nitrided SiO2 devices. In chapter 4, a newly developed ESR technique which we call on-the-fly ESR is utilized to study the triggering mechanisms of NBTI in pure SiO2 devices. Chapter 5 utilizes SDR measurements on SiO2 based structures and attempts to examine the role that fluorine plays in suppressing NBTI in pure SiO2 devices while doing little to suppress NBTI in nitrided SiO 2 devices. Chapter 6 presents a conventional ESR and SDR study which attempts to identify the electronic and physical nature of pre-existing trapping centers in the SiO2 like interfacial layer region of HfO2 based devices which are thought to play important roles in limiting the performance and reliability of these structures.