The effect of native oxide on thin gate oxide integrity

Abstract

We have studied the effect of native oxide on thin gate oxide integrity. Much improved leakage current of gate oxide can be obtained by in situ desorbing the native oxide using a HF-vapor treated and H-2 backed process. Furthermore, extremely sharp interface between oxide and Si is obtained, and good oxide reliability is achieved even under a high current density stress of 11 A/cm(2) and a large charge injection of 7.0 x 10(4) C/cm(2). The presence of native oxide will increase the interface roughness, gate oxide leakage current and stress-induced hole trap.