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Producción Científica, The authors investigate the templated crystallization of thin-body Ge fin structures with high aspect ratios. Experimental variables include fin thickness and thermal treatments, with fin structures oriented in the 〈110〉 direction. Transmission electron microscopy determined that various crystal defects form during crystallization of amorphous Ge regions, most notably {111} stacking faults, twin boundaries, and small crystallites. In all cases, the nature of the defects is dependent on the fin thickness and thermal treatments applied. Using a standard 600 °C rapid-thermal-anneal, Gestructures with high aspect ratios crystallize with better crystal quality and fewer uncured defects than the equivalent Si case, which is a cause for optimism for thin-film Ge devices., Science Foundation Ireland under Research Grant Nos. 09/SIRG/I1623 and 09/SIRG/I1621.

Design and optimization of n-type doped regions in germanium by solid phase epitaxial recrystallization (SPER) have been studied by the authors. A systematic study is presented of process variables that influence activation and thermal stability, including preamorphization, coimplants, recrystallization temperature, and postrecrystallization thermal treatments. Unlike silicon, activation after recrystallization in germanium is not optimum where the postrecrystallization thermal budget is kept to a minimum. With the aid of modeling, a maximum peak activation of 7 X 10(19) cm(-3) was extracted. A steady increase in sheet resistance during postrecrystallization anneals confirms the formation of metastable activation by SPER. It is predicted that active concentrations of 6-8 X 10(19) cm(-3) are sufficient to meet targets for sub-20 nm technologies. (C) 2010 American Institute of Physics. (doi: 10.1063/1.3452345)