SiGe epitaxial growth using screen printing of Al–Ge paste on Si followed by pulsed laser annealing

We have developed a method for growing SiGe epitaxial layers by using screen printing of Al–Ge paste on Si substrates, and then melting the paste locally with pulsed laser annealing. This method builds upon our previous technology for SiGe epitaxial growth using printing and firing of Al–Ge paste under atmospheric pressure to enable non-equilibrium growth. When using a mixed paste containing Al and Ge particles, laser ablation dominates the process, while with a homogeneous AlGe alloyed paste, efficient melting and epitaxial growth occur. Excessive laser irradiation resulted in an inhomogeneous composition with surface irregularities due to Marangoni convection. On the other hand, appropriate laser irradiation led to flat and uniform SiGe formation, paving the way for advancements in the facile growth of metastable semiconductors.