We develop a novel method to fabricate multiform structures of Si nanopillars (diameters >40 nm, aspect ratio > 10, coverage ratio > 35%) by dry etch with self-assembled cesium chloride ( CsCl) nanoislands as mask. The pillars can cover structures of lateral size 1 mu m and unpolished Si wafer, enabling uneven surface to be textured by nanopillars without complex process or expensive polishing. Planar micropatterns and tridimensional localization of nanopillars have been easily realized, useful for integrating nanopillars to devices. By figuring out substrate influences, fast formation of CsCl islands within 1 min has been achieved for the first time, making CsCl process flow to be possibly controlled within 30 min. Based on the deliquescence of salt, CsCl self-assembly is simple, widely tunable and compatible, which endows the approaches great practical potential. (C) 2011 Elsevier B.V. All rights reserved.