Methods of fabricating semiconductor devices having buried channel array

A method of fabricating a semiconductor device comprises forming a first and a second parallel field regions in a substrate, the parallel field regions are extended in a first direction, forming a first and a second gate capping layer in a first and a second gate trench formed in the substrate respectively, removing the gate capping layers partially so that a first landing pad hole is expanded to overlap the gate capping layers buried in the substrate partially, forming a landing pad material layer in the first space, and forming a bit line contact landing pad by planarizing the landing pad material layer to the level of top surfaces of the capping layers.