Vertically oriented amorphous and microcrystalline Si nanorods grown on different substrates were successfully obtained by Cat CVD with the glancing angle incident silane flux at low temperatures. The influences of the substrate type, substrate temperature, post treatment and hydrogen dilution on the microstructure of Si nanorods were investigated. The density and diameter of nanorods are varying with the substrates. The hydrogen dilution of silane dominates the crystallization of Si nanorods rather than high substrate temperature at 550 degrees C and annealing at 900 degrees C in nitrogen for 6 h. The crystallized Si nanorods with crystalline volume fraction, Xc, of 0.55 were achieved under a low substrate temperature of 140 degrees C. (C) 2009 Elsevier B.V. All rights reserved.