Bonding constraints and defect formation at interfaces between crystalline silicon and advanced single layer and composite gate dielectrics

Abstract

An increasingly important issue in semiconductor device physics is understanding of how departures from ideal bonding at silicon–dielectric interfaces generate electrically active defects that limit performance and reliability. Building on previously established criteria for formation of low defect density glasses, constraint theory is extended to crystalline silicon–dielectric interfaces that go beyond Si–SiO2 through development of a model that quantifies average bonding coordination at these interfaces. This extension is validated by application to interfaces between Si and stacked silicon oxide/nitride dielectrics demonstrating that as in bulk glasses and thin films, an average coordination, Nav, greater than three yields increasing defective interfaces.