Thermogravimetric Mass Spectroscopic Analysis During Annealing of HfO2 Thin Films in Argon
EMSL Project ID
6892
Abstract
HfO2 is a promising new gate dielectric material for CMOS devices. The dielectrics must be able to withstand 600 C or more after deposition during subsequent integrated circuit processing. Even though these materials have generated the most excitement and have been the most widely studied in the industry for this application over the last three years, there is evidence that they may decompose if annealled in vacuum or in an inert environment forming a silicide layer (Garfunkel et al. JAP, 94(2)2003pp938). In this paper, the authors used MEIS to determine that Hf remained in the same areal concentration (~8x10^15atoms/cm^2) before and after aneal, while the oxygen disappeared.In a very crude experiment in our laboratory, we deposited thick layers of HfO2 using MOCVD and then performing a furnace anneal at 1000 C in Ar at 1 atm. We placed a clean piece of copper down stream from the furnace, cooled it with cooling water, and observed that Hf and Si adsorbed using XPS. Therefore, we believe Hf also forms volatile species. A TGA experiment with MS may be ideal to quantify this phenomenon. The results would be of great interest to the electronics industry and academic community who are exploring the process limitations of these new materials.
Project Details
Project type
Exploratory Research
Start Date
2004-02-01
End Date
2005-02-03
Status
Closed
Released Data Link
Team
Principal Investigator