Boundary condition for the interface between silicon and silicon oxide

A boundary condition is formulated for the interface of a quantum well embe dded in a material of large energy barrier. Distinct differences are pointe d out between a free-standing film and the quantum well. The boundary condi tion for the effective-mass and envelope-function approach includes the pro perty of the transition layer between the well and the barrier in the form of an adjustable parameter. A full-zone k.p method is used along with the b oundary condition to calculate the energy gap of the quantum well as a func tion of the well thickness. The model fits well the experimental data on mu ltiple Si/SiO2 quantum wells.