Growth Mechanism of MgO Film on Si (100). Domain Matching Epitaxy, Strain Relaxation, Preferred Orientation Formation

Abstract

We present the growth mechanism of MgO film on Si (100), specifically epitaxial growth at the interface strain relaxation at critical thickness, and preferred orientation formation after strain relaxation We first focused on domain matching epitaxy (DME) between MgO and Si with a large lattice mismatch of 224% MgO/Si (100) with 4/3 and 5/4 domain matching during growth of MgO on Si (100) are equally mixed to reduce domain mismatch Two continuous 4/3 domains have domain mismatch of 0 1124 nm, but mixed 4/3 and 5/4 domains have mismatch of only 0 0093 nm The experimental critical thickness for strain relaxation is similar to 100 nm, and this result is supported by theoretical modeling of MgO film growth using an overall film energy model We focus the anisotropic properties of MgO material to explain the preferred orientation in the (111) direction after strain relaxation MgO with strong ionic bonding characteristic has a polar surface along particular orientations in which anions and cations are arranged alternately, this is the MgO (111) orientation This orientation has strong sticking probability and tends to be preferred orientation by adsorbing adatom dominantly