The NBTI degradation phenomenon and the role of hydrogen during NBT stress are presented in this paper. It is found that PBT stress can recover a fraction of Vth shift induced by NBT1. However, this recovery is unstab...The NBTI degradation phenomenon and the role of hydrogen during NBT stress are presented in this paper. It is found that PBT stress can recover a fraction of Vth shift induced by NBT1. However, this recovery is unstable. The original degradation reappears soon after reapplication of the NBT stress condition. Hydrogen-related species play a key role during a device＇s NBT degradation. Experimental results show that the diffusion species are neutral, they repassivate Si dangling bond which is independent of the gate voltage polaxity. In addition to the diffusion towards gate oxide, hydrogen diffusion to Si-substrate must be taken into account for it also has important influence on device degradation during NBT stress.展开更多
This study shows the preparation of a TiO2 coated Pt/C（TiO2/Pt/C） by atomic layer deposition（ALD）,and the examination of the possibility for TiO2/Pt/C to be used as a durable cathode catalyst in polymer electrolyt...This study shows the preparation of a TiO2 coated Pt/C（TiO2/Pt/C） by atomic layer deposition（ALD）,and the examination of the possibility for TiO2/Pt/C to be used as a durable cathode catalyst in polymer electrolyte fuel cells（PEFCs）. Cyclic voltammetry results revealed that TiO2/Pt/C catalyst which has 2 nm protective layer showed similar activity for the oxygen reduction reaction compared to Pt/C catalysts and they also had good durability. TiO2/Pt/C prepared by 10 ALD cycles degraded 70% after 2000 Accelerated degradation test, while Pt/C corroded 92% in the same conditions. TiO2 ultrathin layer by ALD is able to achieve a good balance between the durability and activity, leading to TiO2/Pt/C as a promising cathode catalyst for PEFCs. The mechanism of the TiO2 protective layer used to prevent the degradation of Pt/C is discussed.展开更多
基金Project supported by the National Natural Science Foundation of China （Grant No 60206006）, the Hi-Tech Research ＆ Development Program of China （Grant No 2004AA1Z1070） and the Key Project of Chinese Ministry of Education （Grant No 104172）.
文摘The NBTI degradation phenomenon and the role of hydrogen during NBT stress are presented in this paper. It is found that PBT stress can recover a fraction of Vth shift induced by NBT1. However, this recovery is unstable. The original degradation reappears soon after reapplication of the NBT stress condition. Hydrogen-related species play a key role during a device＇s NBT degradation. Experimental results show that the diffusion species are neutral, they repassivate Si dangling bond which is independent of the gate voltage polaxity. In addition to the diffusion towards gate oxide, hydrogen diffusion to Si-substrate must be taken into account for it also has important influence on device degradation during NBT stress.
基金supported by the Ministry of Knowledge Economy (MKE, Korea) under the Global Collaborative R&D program supervised by the KIAT (N0000698)
文摘This study shows the preparation of a TiO2 coated Pt/C（TiO2/Pt/C） by atomic layer deposition（ALD）,and the examination of the possibility for TiO2/Pt/C to be used as a durable cathode catalyst in polymer electrolyte fuel cells（PEFCs）. Cyclic voltammetry results revealed that TiO2/Pt/C catalyst which has 2 nm protective layer showed similar activity for the oxygen reduction reaction compared to Pt/C catalysts and they also had good durability. TiO2/Pt/C prepared by 10 ALD cycles degraded 70% after 2000 Accelerated degradation test, while Pt/C corroded 92% in the same conditions. TiO2 ultrathin layer by ALD is able to achieve a good balance between the durability and activity, leading to TiO2/Pt/C as a promising cathode catalyst for PEFCs. The mechanism of the TiO2 protective layer used to prevent the degradation of Pt/C is discussed.
