Investigation of atomic vapour deposited TiN/HfO2/SiO2 gate stacks for MOSFET devices

✍ Scribed by Ch. Wenger; M. Lukosius; I. Costina; R. Sorge; J. Dabrowski; H.-J. Müssig; S. Pasko; Ch. Lohe

• Book ID: 104051981
• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 353 KB
• Volume: 85
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/j.mee.2008.05.002

✦ Synopsis

HfO 2 films were grown by atomic vapour deposition (AVD) on SiO 2 /Si (1 0 0) substrates. The positive shift of the flat band voltage of the HfO 2 based metal-oxide-silicon (MOS) devices indicates the presence of negative fixed charges with a density of 5 Â 10 12 cm À2 . The interface trap charge density of HfO 2 /SiO 2 stacks can be reduced to 3 Â 10 11 eV À1 cm À2 near mid gap, by forming gas annealing. The extracted work function of 4.7 eV preferred the use of TiN as metal gate for PMOS transistors. TiN/HfO 2 /SiO 2 gate stacks were integrated into gate-last-formed MOSFET structures. The extracted maximum effective mobility of HfO 2 based PMOS transistors is 56 cm 2 /Vs.