A thermochemical/molecular model is developed for breakdown in high dielectric constant materials and the model suggests that a fundamental relationship exists between dielectric breakdown strength (Ebd) and dielectric constant (k). The model indicates that Ebd should show an approximate (k)−1/2 dependence over a wide range of high dielectric constant materials. The model also predicts that the field-acceleration parameter (γ), from time-dependent dielectric breakdown (TDDB) testing, should increase with dielectric constant. TDDB and Ebd data are presented for model support. The thermochemical model suggests that the very high local electric field (Lorentz-relation/Mossotti-field) in high-k dielectrics tends to distort/weaken the polar molecular bonds making them more susceptible to bond breakage by standard Boltzmann processes and/or by hole capture and thus lowers the breakdown strength.

Low-frequency noise characteristics of HfSiON gate-dielectric metal-oxide-semiconductor-field-effect transistors Appl. Phys. Lett. 86, 082102 (2005); 10.1063/1.1866507 Effects of annealing temperature on the characteristics of HfSi x O y / HfO 2 high-k gate oxides Characteristics of HfO 2 / HfSi x O y film as an alternative gate dielectric in metal-oxide-semiconductor devices

No abstract

A molecular physics-based complementary model, which includes both field and current, is introduced to help resolve the E versus 1/E-model controversy that has existed for many years as to the true physics behind time-dependent dielectric breakdown (TDDB). It is shown here that either TDDB model can be valid for certain specified field, temperature, and molecular bonding-energy ranges. For bond strengths <3 eV, the bond breakage rate is generally dominated by field-enhanced thermal processes and the E model is valid. For bond strengths >3 eV, the bond breakage must be hole catalyzed by current-induced hole injection and capture. Under these conditions, the TDDB physics is described well by the 1/E model.

No abstract

No abstract

No abstract

High dielectric constant materials are being developed as possible replacements for SiO2 as the gate dielectric. Although these materials do overcome the issue of gate leakage current because of increased thickness for a given equivalent capacitance, several other problems arise, such as degraded carrier mobility and higher low-frequency noise due to increased fixed charges and traps in the high-k film. HfSiON gate-dielectric metal-oxide-semiconductor field-effect transistors (MOSFETs), presented here, offer lower 1∕f noise compared to other high-k materials, but the noise levels are relatively higher than in SiO2 devices. Oxide-trap-induced correlated carrier number-mobility fluctuations dominate in all of these devices. Measured noise characteristics as well as extracted oxide trap density values are discussed for various geometries and sizes. The latter, measured to be 1.5×1019–1.6×1020cm−3eV−1, is higher than that for SiO2 MOSFETs with similar dimensions (4.1×1016–7.8×1016cm−3eV−1). This work represents an investigation of interface generated flicker noise on HfSiON gate stacks.