Title :
Suppression of chemical phase separation in high-k zirconium an hafnium nitro-silicate and alumino-silicate alloys for CMOS applications
Author :
Lucovsky, Gerald ; Phillips, James C. ; Whitten, Jerry L.
Author_Institution :
Dept. of Phys., NC State Univ., Raleigh, NC, USA
Abstract :
Thin film pseudo-binary Zr and Hf silicate alloys are non-crystalline as-deposited, but display chemical phase separation (CPS) into ZrO2/HfO2 and SiO2 on annealing to temperatures greater than 900°C. In addition, and depending on the ZrO2/HfO2 concentrations, the ZrO2/HfO2 phases may crystallize as well. Application of bond-constraint theory (BCT) indicates that these alloys are over-constrained, or stress-rigid, so that CPS is anticipated. If concentrations are controlled within narrow limits in pseudo-ternary Zr(Hf) nitro-silicate and alumino-silicate alloys, CPS is completely suppressed by self-organizations which relieve local bond-strain.
Keywords :
aluminium alloys; dielectric materials; hafnium alloys; high-k dielectric thin films; phase separation; zirconium alloys; CMOS; SiO2; ZrO2-HfO2; alumino-silicate alloys; annealing; bond constraint theory; chemical phase separation; hafnium nitro-silicate alloys; high-k thin films; zirconium; Annealing; Bonding; Chemicals; Displays; Hafnium oxide; High K dielectric materials; High-K gate dielectrics; Temperature; Transistors; Zirconium;
Conference_Titel :
Solid-State Device Research Conference, 2005. ESSDERC 2005. Proceedings of 35th European
Print_ISBN :
0-7803-9203-5
DOI :
10.1109/ESSDER.2005.1546665
