Impact of interfacial dipole on effective work function of nickel fully silicided gate electrodes formed on rare-earth-based dielectric interlayers

Abstract

Dielectric and optical properties of epitaxial rare-earth scandate films and their crystallization behavior

Integrations and challenges of novel high-k gate stacks in advanced CMOS technology

“…As such, there is a high degree of polarization between the RE and O ions in the RE-based interlayer. Lim et al [363] have studied the interfacial RE-O dipole moment magnitude l REÀO = qd REÀO , where q is the charge transfer across the dipole layer and proportional to the net electronegativity difference (Dv) between RE and O ion, and d REÀO is approximately the sum of the ionic radii of RE and O ions. They found a clear trend that the larger Dvd REÀO values will have a larger dipole strength.…”

Non-monotonic Surface Charging Behavior of Platinum: A Paradigm Change

“…The crucial impact of surface oxides on the potential distribution and electronic work function has been explored in experiments and using density functional theory (DFT) for semiconductors , and Pt-based electrodes. − DFT calculations of Tian et al were interpreted in terms of a continuous increase of the pzfc of Pt(111) with OH ad coverage . In spite of these attempts, the question how adsorbed oxide layers affect the free charge density of the metal has remained largely elusive.…”

An interface dipole predictive model for high-k dielectric/semiconductor heterostructures using the concept of the dipole neutrality point

“…One intuitive approach is to attribute the formation of interface dipoles to the electronegativity (EN) difference between the high-k oxide and semiconductor. [9][10][11] However, most, if not all, of the high-k oxides possess larger EN when compared to silicon (Si) and therefore only dipoles in one direction should form considering the unidirectional charge transfer. 3 Unfortunately, opposing dipole polarities are common for different high-k oxides on Si and this seems to suggest that EN is not a suitable parameter for predictions of oxide-semiconductor interfaces.…”

“…Yet, there remains strong evidence for the correlation of EN to the strength of interface dipoles. [9][10][11] In this work, we will demonstrate how our dipole neutrality point (DNP) concept can employ EN as a parameter for interface dipoles prediction and, yet at the same time, account for the opposing dipole polarities that are observed in the literature.…”