Doping of 181Hf impurities in the semiconductor Ho2O3 by a ball-milling-assisted solid-state reaction

D. RICHARD; E.L. MUÑOZ; G.N. DARRIBA; L.A. ERRICO; M. RENTERÍA

La Plata

Conferencia; HK 2010; 2011

Alexander von Humboldt Stiftung, UNLP

In this work we study the ball milling assisted solid state reaction doping method between neutron activated mHfO2 and the bixbyite Ho2O3. In order to follow the doping process of 181Hf donor impurities in the semiconductor Ho2O3 and to elucidate the effect of each variable involved in the process, time differential perturbed angular correlation (TDPAC) experiments were carried out after each step of the doping process. The obtained hyperfine parameters were compared to those of mHfO2, using a well established electric field gradient(EFG) systematics for 181Ta in bixbyite sesquioxides, and to TDPAC results obtained in Ho2O3 samples doped by ion implantation of 181Hf(->181Ta). As we will show, we could determine the effect played by the milling and the thermal treatments, showing the capability of the TDPAC technique to follow the doping process and to give information about the interdiffusion processes. We also demonstrate the excellent efficiency of the ball milling assisted solidstate reaction process to locate Hf donor impurities at the defectfree cationic sites of the Ho2O3 semiconductor, quantifying directly the amount of impurities doped after each step of the process.