Channeling Doping Profiles Studies for Small Incident Angle Implantation into Silicon Wafers

Abstract

Traditional de-channeling dopant profiles in the silicon crystal wafers have been achieved by tilting the wafer away from the incident beam. As feature sizes of device shrink, the advantages for channeled doping profiles for implants with small or near zero degree incident angles are being recognized. For example, high-energy CMOS well spacing limitations caused by shadowing and encroachment of the ion beam by photoresist mask can be avoided for near zero degree incident implants. Accurate models of channeled profiles are essential to predict the device performance. This paper mainly discusses the damage effect on channeled dopant profiles. Especially, damage effects on channeled dopant profiles are correlated to ThermaWave (TW) measurements. It is demonstrated that there is a critical dose at which the damage effects have to be considered for channeled dopant profile evolvements. EXPERIMENTAL DETAILS All SIMS samples are 200mm wafers with only native oxide as the top-layer. Wafers are implanted on VIISta 810 medium-current ion implanter. In the

Enhanced phenomenological models of ion channeling contribution to doping profiles in crystals

“…To validate our models, a large array of experimental and simulation data available in publications [32][33][34][35][36][37][38][39][40] has been used. Their model description was carried out by means of the LevenbergMarquardt method of NLSq fitting.…”

“…Experimental SIMS data picked up from various sources [32][33][34][35][36][37][38] were fitted using both the 8-parameter model developed in section 4, and the standard 9-parameter "dual Pearson" model. It is clear that both models are qualitatively applicable to fit all the data.…”