Fabrication of Si nano-pillar array through Ni nano-dot mask using inductively coupled plasma

We formed Si nano-pillar array using inductively coupled plasma (ICP) etching of Si with Ni nano-dot mask. For the formation of Ni nano-dot mask, Ni was deposited on Si substrate using sputtering. Through rapid thermal annealing (RTA) of Ni layer at 700°C, Ni nano-dot array was formed on Si substrate. Effects of etching parameters such as rf power, bias voltage and gas composition on the morphologies of Si nano-pillar array were investigated. Optimum etching of Si with Ni nano-dot mask was obtained under the bias voltage of -90 V, power of 1500 W and gas composition of CF₄ (70%) and sulfur hexafluoride (SF₆; 30%). Si nano-pillar array with a diameter smaller than 50 nm and aspect ratio larger than 10 was formed.