Formation of Si wells and pyramids on (1 0 0) surface as a result of ZnSi interaction

Abstract

Interaction between metallic zinc and Si wafer at moderately high temperatures was found to generate either concave wells or hollow pyramid-shaped protrusions on the (1 0 0) wafer surface. The formation of the wells is attributed to the dissolution of silicon at temperatures much lower than its melting point in the form of ZnSi eutectic. When the temperature was raised, Zn atoms in the eutectic droplets evaporated and Si atoms in them precipitated accordingly. If a droplet contained plenty of Si atoms, these Si atoms could encounter each other during precipitation at the surface of the droplet and condense into a hollow pyramid-shaped protrusion. © 2011 Elsevier Ltd. All rights reserved.