A set of numerical experiments designed to analyze the oceanic forcing in spring show that the combined forcing of cold （warm） El Ni（n）o （La Ni（n）a） phases in the Ni（n）o4 region and sea surface temperature a...A set of numerical experiments designed to analyze the oceanic forcing in spring show that the combined forcing of cold （warm） El Ni（n）o （La Ni（n）a） phases in the Ni（n）o4 region and sea surface temperature anomalies （SSTA） in the westerly drifts region would result in abnormally enhanced NorthEast Cold Vortex （NECV） activities in early summer.In spring,the central equatorial Pacific El Ni（n）o phase and westerly drift SSTA forcing would lead to the retreat of non-adiabatic waves,inducing elliptic low-frequency anomalies of tropical air flows.This would enhance the anomalous cyclone-anticyclonecyclone-anticyclone low-frequency wave train that propagates from the tropics to the extratropics and further to the mid-high latitudes,constituting a major physical mechanism that contributes to the early summer circulation anomalies in the subtropics and in the North Pacific mid-high latitudes.The central equatorial Pacific La Ni（n）a forcing in the spring would,on the one hand,induce teleconnection anomalies of high pressure from the Sea of Okhotsk to the Sea of Japan in early summer,and on the other hand indirectly trigger a positive low-frequency East Asia-Pacific teleconnection （EAP） wave train in the lower troposphere.展开更多
A novel silicon-on-insulator（SOI） high breakdown voltage（BV） power device with interlaced dielectric trenches（IDT） and N/P pillars is proposed. In the studied structure, the drift region is folded by IDT embedde...A novel silicon-on-insulator（SOI） high breakdown voltage（BV） power device with interlaced dielectric trenches（IDT） and N/P pillars is proposed. In the studied structure, the drift region is folded by IDT embedded in the active layer,which results in an increase of length of ionization integral remarkably. The crowding phenomenon of electric field in the corner of IDT is relieved by the N/P pillars. Both traits improve two key factors of BV, the ionization integral length and electric field magnitude, and thus BV is significantly enhanced. The electric field in the dielectric layer is enhanced and a major portion of bias is borne by the oxide layer due to the accumulation of inverse charges（holes） at the corner of IDT.The average value of the lateral electric field of the proposed device reaches 60 V/μm with a 10 μm drift length, which increases by 200% in comparison to the conventional SOI LDMOS, resulting in a breakdown voltage of 607 V.展开更多
For 20 V planar active-gap lateral double-diffused MOSFET （LDMOS）, the sectional channel is utilized to decrease the electric field in the n-drift region below the poly gate edge in the off-state, compared with the ...For 20 V planar active-gap lateral double-diffused MOSFET （LDMOS）, the sectional channel is utilized to decrease the electric field in the n-drift region below the poly gate edge in the off-state, compared with the conventional single channel. Then the n-drift concentration can be increased to decrease the Kirk effect, while keeping off-state breakdown voltage Vbd unchanged. Meanwhile the influence of the n-drift concentration and the n-drift length Ldrift （the drain n＋ diffusion to gate spacing） which are related to the Kirk effect is discussed. The trade-offs between Rdson.Area, breakdown voltage Vbd and the electrical safe operating area （e-SOA） performance of LDMOS are considered also. Finally the proposed planar active-gap LDMOS devices with varied values of Ldria are experimentally demonstrated. The experimental results show that the Kirk effect can be greatly suppressed with slight increase in the Rdson.Area parameter.展开更多
基金supported by a National Natural Science Foundation project approved under Grant Nos.41175083,41275096 and 41305091a China Meteorological Administration special public welfare reserch funds registeredunder Grant Nos.GYHY201006020,GYHY 201106016,and GYHY201106015
文摘A set of numerical experiments designed to analyze the oceanic forcing in spring show that the combined forcing of cold （warm） El Ni（n）o （La Ni（n）a） phases in the Ni（n）o4 region and sea surface temperature anomalies （SSTA） in the westerly drifts region would result in abnormally enhanced NorthEast Cold Vortex （NECV） activities in early summer.In spring,the central equatorial Pacific El Ni（n）o phase and westerly drift SSTA forcing would lead to the retreat of non-adiabatic waves,inducing elliptic low-frequency anomalies of tropical air flows.This would enhance the anomalous cyclone-anticyclonecyclone-anticyclone low-frequency wave train that propagates from the tropics to the extratropics and further to the mid-high latitudes,constituting a major physical mechanism that contributes to the early summer circulation anomalies in the subtropics and in the North Pacific mid-high latitudes.The central equatorial Pacific La Ni（n）a forcing in the spring would,on the one hand,induce teleconnection anomalies of high pressure from the Sea of Okhotsk to the Sea of Japan in early summer,and on the other hand indirectly trigger a positive low-frequency East Asia-Pacific teleconnection （EAP） wave train in the lower troposphere.
基金Project supported by the Guangxi Natural Science Foundation of China(Grant Nos.2013GXNSFAA019335 and 2015GXNSFAA139300)Guangxi Experiment Center of Information Science of China(Grant No.YB1406)+2 种基金Guangxi Key Laboratory of Wireless Wideband Communication and Signal Processing of China,Key Laboratory of Cognitive Radio and Information Processing(Grant No.GXKL061505)Guangxi Key Laboratory of Automobile Components and Vehicle Technology of China(Grant No.2014KFMS04)the National Natural Science Foundation of China(Grant Nos.61361011,61274077,and 61464003)
文摘A novel silicon-on-insulator（SOI） high breakdown voltage（BV） power device with interlaced dielectric trenches（IDT） and N/P pillars is proposed. In the studied structure, the drift region is folded by IDT embedded in the active layer,which results in an increase of length of ionization integral remarkably. The crowding phenomenon of electric field in the corner of IDT is relieved by the N/P pillars. Both traits improve two key factors of BV, the ionization integral length and electric field magnitude, and thus BV is significantly enhanced. The electric field in the dielectric layer is enhanced and a major portion of bias is borne by the oxide layer due to the accumulation of inverse charges（holes） at the corner of IDT.The average value of the lateral electric field of the proposed device reaches 60 V/μm with a 10 μm drift length, which increases by 200% in comparison to the conventional SOI LDMOS, resulting in a breakdown voltage of 607 V.
文摘For 20 V planar active-gap lateral double-diffused MOSFET （LDMOS）, the sectional channel is utilized to decrease the electric field in the n-drift region below the poly gate edge in the off-state, compared with the conventional single channel. Then the n-drift concentration can be increased to decrease the Kirk effect, while keeping off-state breakdown voltage Vbd unchanged. Meanwhile the influence of the n-drift concentration and the n-drift length Ldrift （the drain n＋ diffusion to gate spacing） which are related to the Kirk effect is discussed. The trade-offs between Rdson.Area, breakdown voltage Vbd and the electrical safe operating area （e-SOA） performance of LDMOS are considered also. Finally the proposed planar active-gap LDMOS devices with varied values of Ldria are experimentally demonstrated. The experimental results show that the Kirk effect can be greatly suppressed with slight increase in the Rdson.Area parameter.
