Blistering studies in InP, LaAlO3
S. Christiansen and O. Moutanabbir
Heterogeneous integration of InP with silicon is of great technological importance since it would lead to the integration of Si-based microelectronic devices with InP-based optoelectronic devices. Heteroepitaxial growth of InP layers on Si is not a viable solution due to the large lattice mismatch between InP and Si (8.1%). Heteroepitaxy of InP on Si would result in highly defective epitaxial layers containing an unacceptably large density of threading dislocations and antiphase boundaries. One of the methods to fabricate low-cost and high structural quality substrates, comparable to bulk InP would be direct wafer bonding and layer transfer of thin InP layers via H/He implantation and layer splitting upon annealing. The physical mechanisms leading to the process of layer splitting can conveniently be investigated in blistering studies. These studies involve H/He implantation and annealing of unbonded wafers.
Fig. 5: XTEM image of the InP layer transferred onto the Si handle wafer. The top 300 nm layer is heavily damaged due to helium implantation-induced defects while the lower 350 nm layer is comparatively much less damaged.
LaAlO3 is an intersting material for the epitaxial growth of GaN. Blistering and layer transfer studies are therefore conducted at the institute.