Title :
Stability of crystalline Gd2O3 thin films on silicon during post-growth processing
Author :
Schwendt, D. ; Tetzlaff, D. ; Bugiel, E. ; Osten, H.J. ; Gottlob, H.D.B.
Author_Institution :
Inst. of Electron. Mater. & Devices, Leibniz Univ., Hannover, Germany
Abstract :
Experimental results for crystalline Gd2O3-based MOS capacitors show that these layers are excellent candidates for application as very thin high-K materials replacing SiO2 in future MOS devices. First electrical characteristics of n- and p-type SOI-MOSFETs with epitaxial Gd2O3 demonstrate the general feasibility of this novel gate insulator, but thermal stability during typical CMOS annealing processes has been identified as a key issue. Here, we investigate the effect of post-growth annealing on layer properties. Standard forming gas anneal can eliminate flatband instabilities and hysteresis as well as reduce leakage currents by saturating dangling bond caused by the bonding mismatch. In addition, we investigated the impact of rapid thermal anneals on structural and electrical properties of crystalline Gd2O3 layers grown on Si. Finally, we will show a new way to improve the thermal stability of those crystalline layers significantly.
Keywords :
MOS capacitors; MOSFET; annealing; gadolinium compounds; high-k dielectric thin films; silicon; silicon-on-insulator; CMOS annealing processes; Gd2O3-Si; MOS capacitors; MOS devices; bonding mismatch; crystalline layers; crystalline thin films; dangling bond; electrical characteristics; electrical properties; flatband instabilities; gate insulator; layer properties; leakage currents; n-type SOI-MOSFET; p-type SOI-MOSFET; post-growth annealing; post-growth processing; rapid thermal anneals; standard forming gas anneal; structural properties; thermal stability; very thin high-k materials; Bonding; Crystalline materials; Crystallization; High K dielectric materials; High-K gate dielectrics; MOS capacitors; Rapid thermal annealing; Semiconductor thin films; Silicon; Thermal stability; High-K dielectrics; forming gas anneal; gadolinium oxide; gadolinium silicate; temperature stability;
Conference_Titel :
Signals, Circuits and Systems (SCS), 2009 3rd International Conference on
Conference_Location :
Medenine
Print_ISBN :
978-1-4244-4397-0
Electronic_ISBN :
978-1-4244-4398-7
DOI :
10.1109/ICSCS.2009.5414206
