Detection of Border Trap Density and Energy Distribution Along the Gate Dielectric Bulk of High- \kappa Gated MOS Devices

• Published in: IEEE electron device letters Vol. 28; no. 5; pp. 432 - 435
• Main Authors: Lu, Chun-Yuan, Chang-Liao, Kuei-Shu, Lu, Chun-Chang, Tsai, Ping-Hung, Wang, Tien-Ko
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.05.2007; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Border traps; charge pumped per cycle (Q_{ \rm cp}); charge pumping (CP); Charge pumps; Compound structure devices; depth profile; Dielectric devices; Electronics; Exact sciences and technology; Frequency; Hafnium oxide; hbox{HfO}_{x}\hbox{N}_{y} dielectric; MOS devices; MOSFETs; near-interface traps; Rapid thermal annealing; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Semiconductor films; Silicon; Transistors; Tunneling; MOSFET; High density; Energy distribution; Tunnel effect; Border traps; MOS structure; Energy density; Density distribution; charge pumped per cycle (Qcp); Energy dependence; near- interface traps; Depth profile; HfOxNy dielectric; High k dielectric; Charge pumping; charge pumping (CP)
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2007.895379

A novel charge-pumping (CP) technique is demonstrated to extract border-trap distribution for high- kappa gated MOSFETs. The varying-frequency CP method is shown to be more effective than the varying-amplitude one for probing border traps and extending the tunneling depth. A linear relationship of the Q cp versus ln(T r T f ) 1/2 plot can only be maintained at the CP frequency of 1 MHz, while not below 1 MHz, due to the influence of border traps near HfO x N y /Si interface. The proposed technique, which takes into consideration the effect of carrier tunneling in slow oxide traps, is used successfully to obtain the spatial and energy dependence of bulk trap density in high-kappa bulk