Abstract
An amorphous Yb 2 O 3 passivation layer integrated with a crystalline ZrTiO 4 film was explored as the advanced gate stack for Ge MOS devices. The ZrTiO 4 /Yb 2 O 3 gate stack demonstrates D it of 2.4 × 10 11 cm -2 ·eV -1 and EOT down to 0.76 nm which are, respectively, due to the formation of an interfacial YbGeO x layer that well passivates the dangling bonds at Ge surface and the adoption of a crystalline ZrTiO 4 film with a κ value of 45.6. The gate stack also shows low leakage current, tight distribution of device parameters, and desirable reliability performance, paving an alternative avenue to develop high-performance Ge MOS devices. © 2002-2012 IEEE.