Characterization of reactive ion etching of sol-gel SiO 2 using Taguchi optimization method

Abstract

SiO 2 films prepared using sol-gel technique have found enormous potential applications in photonics, electronics and sensor devices. However, the feasibility of the devices utilizing sol-gel technology lies on the ease of the fabrication processes such as patterns transfer using wet or dry etchings. Dry etching is preferred over wet etching as it is able to produce finer features with high anisotropic etch profile. In this paper, we report the development of a dry reactive ion etching (RIE) process for sol-gel SiO 2 using a mixture of CF 4 and O 2 plasma. Parameters such as RF power, chamber pressure, CF 4 and O 2 flow rate, were optimized using a statistical method called Taguchi Technique. Etch rate of as high as 50nm/min, with high anisotropy etched profile, has been obtained.