Study of Submicron SrTiO3 Patterning

Abstract
Features of thin strontium titanate (SrTiO3) films are a high dielectric constant (εr) and chemical and structural stability. Submicron SrTiO3 patterning is necessary for realizing future planar dynamic random access memory (DRAM) structures to suppress parasitic capacitance. The etching technology and reaction with SrTiO3 film were investigated. It was found that the SrTiO3 film could be chemically etched by Cl2 and SF6 mixture gas, and 0.6 µm SrTiO3 patterns were etched by Cl2 with 10%-SF6 gases. In addition, the side wall deposition layer was removed by rinsing with CH3COOH, HNO3 and HF mixture solution.