Current Advances in Anhydrous HF/Organic Solvent Processing of Semiconductor Surfaces

Abstract

The process in which anhydrous HF (AHF) is mixed with the vapor of an organic solvent for the purpose of etching of native SiO2 on Si surfaces is well established (e.g [1-4]). The process was also explored as part of a dry-wet wafer cleaning sequence [5]. More recently, the same process has been successfully expanded into MEMS technology for the purpose of stiction-free releasing of structures by isotropic etching of sacrificial SiO2 [6,7]. The current strong push in advanced Si digital IC technology toward extremely fragile 3D geometries engraved on Si wafer surfaces, in which case conventional etch methods may not work properly [8], as well as needs with regard to native oxide etching in emerging Si-based technologies such as solar cell manufacturing has brought about renewed interest in AHF technology.