Mechanism of dislocation formation during vertical solid phase epitaxy

Abstract

In order to improve Si crystal on insulator (SOI) by lateral solid phase epitaxy (L-SPE), the crystallinity of vertical SPE (V-SPE) region as the initial step for L-SPE growth has been investigated using high resolution cross-sectional transmission electron microscopy (HR-XTEM). The cleaning process using Si 2H 6 as a reducer at 850°C caused vertical dislocations in the V-SPE region, due to insufficient removal of native oxide in the seed area. The mechanism of dislocation formation has turned out to be an incoherent merging of crystalline fronts on top of oxide islands after nucleation at the partially cleaned area of the seed region and subsequent climbing up the oxide islands.