Au-Assisted catalytic growth of Si2Te3 plates

Abstract

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.