Au-Assisted catalytic growth of Si2Te3 plates
Post-transition metal dichalcogenides (P-TMDC) are a promising material group for their unique electronic properties and possibilities for high performance transistor and photodetector devices. As a layered p-type semiconductor of this group, silicon telluride (Si2Te3) is an emerging material due to its wide band gap, near-infrared photoluminescence, optical tuning, and resistive switching properties. However, the synthesis and corresponding study on the growth mechanism of Si2Te3 have rarely been reported. In this work, we synthesized Si2Te3 plates on Si substrates using Au particles as a catalyst. The Au particles enabled the liquid phase reaction with Si and Te due to the eutectic alloy formation of Au–Si and Au–Te. This study presents a series of growth mechanisms: (i) Si2Te3 nuclei formed from the eutectic alloy particles, (ii) formation of Te-rich rods overgrown from the Si2Te3 nuclei, (iii) conversion of the Te-rich rods to Si2Te3 rods, and (iv) transformation of the Si2Te3 rods into horizontal Si2Te3 plates. This study provides an understanding of the reaction and growth mechanism of Si2Te3 plates.