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

An increasingly important issue in semiconductor device physics is understa nding of how departures from ideal bonding at silicon-dielectric interfaces generate electrically active defects that limit performance and reliabilit y. Building on previously established criteria for formation of low defect density glasses, constraint theory is extended to crystalline silicon-diele ctric interfaces that go beyond Si-SiO2 through development of a model that quantifies average bonding coordination at these interfaces. This extensio n is validated by application to interfaces between Si and stacked silicon oxide/nitride dielectrics demonstrating that as in bulk glasses and thin fi lms, an average coordination, N (av), greater than three yields increasing defective interfaces. (C) 1999 American Institute of Physics. [S0003-6951(9 9)00414-3].