Artículos de revistas
Theoretical investigation of Hf and Zr defects in c-Ge
Fecha
2009Registro en:
JOURNAL OF PHYSICS-CONDENSED MATTER, v.21, n.1, 2009
0953-8984
10.1088/0953-8984/21/1/012206
Autor
Scopel, Wanderla L
Fazzio, Adalberto
Silva, Antonio Jose Roque da
Institución
Resumen
The introduction of high-permittivity gate dielectric materials into complementary metal oxide semiconductor technology has reopened the interest in Ge as a channel material mainly due to its high hole mobility. Since HfO(2) and ZrO(2) are two of the most promising dielectric candidates, it is important to investigate if Hf and Zr may diffuse into the Ge channel. Therefore, using ab initio density functional theory calculations, we have studied substitutional and interstitial Hf and Zr impurities in c-Ge, looking for neutral defects. We find that (i) substitutional Zr and Hf defects are energetically more favorable than interstitial defects; (ii) under oxygen-rich conditions, neither Zr nor Hf migration towards the channel is likely to occur; (iii) either under Hf- or Zr-rich conditions it is very likely, particularly for Zr, that defects will be incorporated in the channel.