Roles of high-k and interfacial layers on TDDB reliability studied with HfAlO<inf>X</inf>/SiO<inf>2</inf> stacked gate dielectrics

Reliability of HfAlO<inf>x</inf> in multi layered gate stack

“…It is well known that in case of time dependent breakdown for high-κ/SiO 2 dielectric stack, the primary role of high-k layer is to determine the dominating current component which degrades both high-k and interfacial layers. The interfacial layer initiates the breakdown process and subsequently the whole dielectric stack collapses when a percolation path creates through the entire dielectric [5]. Therefore, the highest charge to break down or time to breakdown was observed for sample B 1 having the lowest Al available to the IL.…”

“…INTRODUCTION HfAlO x with various composition have attracted tremendous attention for high-κ/metal gate (HK-MG) stack for CMOS semiconductor devices [1][2][3][4][5]. Incorporation of aluminum into HfO 2 by forming (HfO 2 ) 1-x (Al 2 O 3 ) x films [1][2][5][6][7][8][9][10][11][12] or HfO 2 /Al 2 O 3 bi-layers [2,[13][14] was reported to be promising for high-κ on silicon and high mobility substrates.…”

“…Incorporation of aluminum into HfO 2 by forming (HfO 2 ) 1-x (Al 2 O 3 ) x films [1][2][5][6][7][8][9][10][11][12] or HfO 2 /Al 2 O 3 bi-layers [2,[13][14] was reported to be promising for high-κ on silicon and high mobility substrates. The addition of Al into HfO 2 can downscale the equivalent oxide thickness (EOT), reduces the gate leakage current density (J g ) and provides a better thermal stability on Si [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. However, Al concentration in the dielectrics needs to be maintained to an extremely low level for highly scaled transistors.…”

Multilayered ALD HfAlO_x and HfO₂ for High-Quality Gate Stacks

“…O VER the past decade, HfAlO x with various composition have attracted tremendous attention for high-κ/metal gate stack for CMOS semiconductor devices [1]- [5]. The incorporation of aluminum into HfO 2 by forming (HfO 2 ) 1−x (Al 2 O 3 ) x films [1], [2], [5]- [12] or HfO 2 /Al 2 O 3 bi-layers [2], [13], [14] was reported to be promising for high-κ gate dielectrics on silicon and high mobility substrates.…”

Correlation of Negative Bias Temperature Instability and Breakdown in HfO2/TiN Gate Stacks

“…Recently, various reliability issues for this new dielectric are getting a lot of attention. Separate studies on Negative Bias Temperature Instability (NBTI) and Time Dependent Dielectric Breakdown (TDDB) have been performed extensively on high-k/metal gate stacks (4)(5)(6)(7)(8)(9)(10).…”