The future of high-K on pure germanium and its importance for Ge CMOS

Abstract A comparison between atomic layer chemical vapor deposition (ALCVD) and metal organic chemical vapor deposition (MOCVD) HfO 2 layers on Ge indicate that ALCVD layers have some improved capacitor characteristics. An NH 3 pre-treatment was essential to obtain MOS C–V characteristics for the deposited HfO 2 layer. We also report for the first time, deep sub-micron Ge pFETs made in a silicon-like process flow with a directly etched metal gate stack on a HfO 2 dielectric. The results indicate that for improving Ge devices, more understanding on the dopant diffusion control and the reduction of interface state density will be necessary.