Three small bandgap non-fullerene(SBG NFAs) acceptors,BDTI,BDTI-2 F and BDTI-4 F,based on a carbon-oxygen bridged central core and thieno[3,4-b]thiophene linker,end-capped with varied electronwithdrawing terminal grou...Three small bandgap non-fullerene(SBG NFAs) acceptors,BDTI,BDTI-2 F and BDTI-4 F,based on a carbon-oxygen bridged central core and thieno[3,4-b]thiophene linker,end-capped with varied electronwithdrawing terminal groups,were designed and synthesized.The acceptors exhibit strong absorption from 600 nm to 1000 nm.The optimal device incorporating designed NFA and PTB7-Th polymer donor achieves a power conversion efficiency of 9.11% with near 0 eV HOMO offset.The work presents a case study of efficient non-fullerene solar cells with small HOMO offsets,which is achieved by blending PTB7-Th with fine-tuned SBG acceptor.展开更多
A small bandgap and light carrier effective mass(mo)lead to obv ous ambipolar transport behavior in carbon nanotube(CNT)fild-effect transistors(FE Ts),including a high off-state current and severe degradation of the s...A small bandgap and light carrier effective mass(mo)lead to obv ous ambipolar transport behavior in carbon nanotube(CNT)fild-effect transistors(FE Ts),including a high off-state current and severe degradation of the subthreshold swing(SS)with increasing drain bias voltage.We demonstrate a drain-engineered method to cope with this common problem in CNT-film FETs with a sub-μum channel length,i.e.,suppressing the ambipolar behavion while maintaining high on-state performance by adopting a feedback gate(FBG)structure to extend the drain region from the CNT/metal contact to the proximate CNT channels to suppress the tunneling current.Sub-400-nm-channel-length FETs with a FBG structure statistially present a high on/off ratio of up to 10*and a sub-200 mV/dec SS under a high drain bias of up to-2 V whle maintaining a high on-state current of 0.2 mA/μm or a peak transconductance of 0.2 mS/um.By lowering the supply voltage to 1.5 V,FBG CNT-fim FETs can meet the requirement of standard-pertormance ultra large scale integrated circuits(ULSICs).Therefore,the introduction of the drain engineering structure enables applications of CNT-film-based FETs in ULSICs and could also be widely extended to other small-bandgap semiconductor-based FETs for an improvement in their off-state property.展开更多
基金the National Key R&D Program of China (2017YFA0204701)Strategic Priority Research Program of the Chinese Academy of Sciences (XDB12010200)+1 种基金National Basic Research Program of China (Program 973) (No. 2014CB643502)the National Natural Science Foundation of China (21572234, 21661132006, 91833304, 21402194) for their financial support。
文摘Three small bandgap non-fullerene(SBG NFAs) acceptors,BDTI,BDTI-2 F and BDTI-4 F,based on a carbon-oxygen bridged central core and thieno[3,4-b]thiophene linker,end-capped with varied electronwithdrawing terminal groups,were designed and synthesized.The acceptors exhibit strong absorption from 600 nm to 1000 nm.The optimal device incorporating designed NFA and PTB7-Th polymer donor achieves a power conversion efficiency of 9.11% with near 0 eV HOMO offset.The work presents a case study of efficient non-fullerene solar cells with small HOMO offsets,which is achieved by blending PTB7-Th with fine-tuned SBG acceptor.
基金the National Key Research and Development Program(No.2016YFA0201901)the National Natural Science Foundation of China(Nos.61888102,61621061,and 61427901)the Beijing Municipal Science and Technology Commission(No.DI711000066170021-2).
文摘A small bandgap and light carrier effective mass(mo)lead to obv ous ambipolar transport behavior in carbon nanotube(CNT)fild-effect transistors(FE Ts),including a high off-state current and severe degradation of the subthreshold swing(SS)with increasing drain bias voltage.We demonstrate a drain-engineered method to cope with this common problem in CNT-film FETs with a sub-μum channel length,i.e.,suppressing the ambipolar behavion while maintaining high on-state performance by adopting a feedback gate(FBG)structure to extend the drain region from the CNT/metal contact to the proximate CNT channels to suppress the tunneling current.Sub-400-nm-channel-length FETs with a FBG structure statistially present a high on/off ratio of up to 10*and a sub-200 mV/dec SS under a high drain bias of up to-2 V whle maintaining a high on-state current of 0.2 mA/μm or a peak transconductance of 0.2 mS/um.By lowering the supply voltage to 1.5 V,FBG CNT-fim FETs can meet the requirement of standard-pertormance ultra large scale integrated circuits(ULSICs).Therefore,the introduction of the drain engineering structure enables applications of CNT-film-based FETs in ULSICs and could also be widely extended to other small-bandgap semiconductor-based FETs for an improvement in their off-state property.