The VFB Modulation Effect of ALD Grown Al2O3, SrO, La2O3 Capping Layers with HfO2 Gate Dielectrics

作     者：Sang Young Lee Hyung-Suk Jung Hyo Kyeom Kim Sang Woon Lee Yu Jin Choi Cheol Seong Hwang 

作者机构：WCU Hybrid Materials Program Department of Materials Science and Engineering and Inter-university Semiconductor Research Center Seoul National University 599 Gwanak-ro Gwanak-gu Seoul 151-742 Republic of Korea WCU Hybrid Materials Program Department of Materials Science and Engineering and Inter-university Semiconductor Research Center Seoul National University Gwanak-Ro Seoul city 151-744 Republic of Korea Department of Materials Science and Engineering Seoul National University 30-217 daehak-dong gwanak-gu Seoul 151-744 Republic of Korea Seoul National University MSE Seoul National University San#56-1 Shillimdong Seoul 151-744 Republic of Korea 

出 版 物：《ECS Transactions》 

年 卷 期：2011年第33卷第3期

摘      要：The effect of atomic layer deposited Al2O3, SrO, and La2O3 capping layers with HfO2 gate dielectrics were examined ffor flat band voltage (VFB) modulation. Al2O3 capping layers cause a VFB shift into the positive voltage direction, while SrO and La2O3 capping layers cause a shift into the negative voltage direction. The bottom capping layer, which positions between the Si substrate and the HfO2 dielectric was more effective in modulating the VFB compared to the top capping layer. The insulating properties of the gate dielectric stacks with different capping layers were also examined. X-ray photoelectron spectroscopy analysis verified that top capping layers did not generally diffuse to the interface between the Si substrate and the HfO2 dielectrics, which supports the result that bottom capping layers are more effective in modulating the VFB.