Title :
Thermal budget impact on HKMG Al2O3 and La gate stacks for advanced DRAM periphery transistors
Author :
Ritzenthaler, R. ; Schram, T. ; Spessot, A. ; Caillat, Christian ; Na, H.-J. ; Lee, S.-G. ; Son, Yeongrack ; Noh, K.B. ; Aoulaiche, Marc ; Arimura, H. ; Horiguchi, Naoto ; Fazan, P. ; Thean, A.
Author_Institution :
IMEC, Leuven, Belgium
Abstract :
In this paper, the effects of various DRAM related thermal budgets on DRAM peripheral gate stacks using Al2O3, capping, La capping, and As I/I are evaluated. It is shown that Al2O3 (PMOS stacks) and As I/I (NMOS stacks) are relatively immune to the aggressive thermal budgets imposed by the DRAM process flow. Apart from the traditional trade-off between eWF shift and gate stack mobility, it is shown that La based stacks are more seriously impacted. The eWF is reduced, but the mobility is degraded through an interface state density increase. However, PBTI is improved with thermal budget owing to thinner EOT, despite a small interfacial layer consumption.
Keywords :
DRAM chips; MOSFET; aluminium compounds; carrier mobility; high-k dielectric thin films; interface states; lanthanum; Al2O3; DRAM peripheral gate stacks; DRAM process flow; HKMG; La; La capping; La gate stacks; NMOS stacks; PMOS stacks; advanced DRAM periphery transistors; gate stack mobility; high-k metal gate; interface state density; interfacial layer consumption; thermal budget impact; Aluminum oxide; Annealing; High K dielectric materials; Logic gates; MOS devices; Random access memory; Tin; Alumina capping; Arsenic ion Implantation; DRAM periphery transistors; La capping;
Conference_Titel :
Microelectronics And Electron Devices (WMED), 2014 IEEE Workshop On
Conference_Location :
Boise, ID
Print_ISBN :
978-1-4799-2222-2
DOI :
10.1109/WMED.2014.6818721
