Inorganic electronics are mainly based on complementary metal–oxide-semiconductor(CMOS)structures that use both ptype and n-type transistors.The complementary structures have promoted the achievement of logic circuit...Inorganic electronics are mainly based on complementary metal–oxide-semiconductor(CMOS)structures that use both ptype and n-type transistors.The complementary structures have promoted the achievement of logic circuits with low power consumption and good noise margin(NM).Compared with inorganic semiconductors,organic solution-processable ambipolar polymers are promising materials for complementary technology[1,2].Ambipolar polymers as single-component semiconductors in CMOS-like circuits maintain the attraction of low cost and easy fabrication[3].In practical application,CMOS-like circuits are expected to employ ambipolar field-effect transistor(FET)based inverters with high gain and good NM[4].However,high-gain inverters with good NM(Table S1 online)are difficult to achieve due to the lack of ambipolar polymers with balanced hole/electron mobilities(lh/le)and threshold voltages.Ambipolar polymers can be obtained by fine-tuning both the highest occupied molecular orbital(HOMO)and lowest unoccupied molecular orbital(LUMO)levels to match well with work function of Au electrodes(WF,4.7–5.2 eV)[5](Fig.S1a online).However,most polymers based on common acceptors only display unipolar(p-type or n-type)transport due to their wide bandgaps(>1.2 eV)and inappropriate energy levels[6].For example,isoindigo-based polymers generally show p-type semiconducting behaviors owing to their high-lying LUMO levels,which is unfavorable for electron injection(Fig.S1b online).展开更多
The conventional charge transport models based on density- and field-dependent mobility, only having a non-Arrhenius tem- perature dependence, cannot give good current-voltage characteristics of poly （2-methoxy-5-（2...The conventional charge transport models based on density- and field-dependent mobility, only having a non-Arrhenius tem- perature dependence, cannot give good current-voltage characteristics of poly （2-methoxy-5-（2＇-ethylhexyloxy）-p-phenylene vinylene） （MEH-PPV） hole-only devices. In this paper, we demonstrate that the current-voltage characteristics can give a good unified description of the temperature, carrier density mad electric field dependence of mobility based on both the Arrhenius temperature dependence and the non-Arrhenius temperature dependence. Fu^hermore, we perform a systematic study of charge transport and electrical properties for MEH-PPV. It is shown that the boundary carrier density has an important effect on the current-voltage characteristics. Too large or too small values of boundary carrier density will lead to incorrect cur- rent-voltage characteristics. The numerically calculated carrier density is a decreasing function of the distance to the interface, and the numerically calculated electric field is an increasing function of the distance. Both the maximum of carrier density and the minimum of electric field appear near the interface.展开更多
基金supported by the National Natural Science Foundation of China(61890940,21922511,91833306,and 91833304)the National Key R&D Program of China(2018YFA0703200)+2 种基金the CAS Key Research Program of Frontier Sciences(QYZDY-SSWSLH029)Research Program of the Chinese Academy of Sciences(XDB30000000)the CAS-Croucher Funding Scheme for Joint Laboratories,and the CAS Cooperation Project(121111KYSB20200036)。
文摘Inorganic electronics are mainly based on complementary metal–oxide-semiconductor(CMOS)structures that use both ptype and n-type transistors.The complementary structures have promoted the achievement of logic circuits with low power consumption and good noise margin(NM).Compared with inorganic semiconductors,organic solution-processable ambipolar polymers are promising materials for complementary technology[1,2].Ambipolar polymers as single-component semiconductors in CMOS-like circuits maintain the attraction of low cost and easy fabrication[3].In practical application,CMOS-like circuits are expected to employ ambipolar field-effect transistor(FET)based inverters with high gain and good NM[4].However,high-gain inverters with good NM(Table S1 online)are difficult to achieve due to the lack of ambipolar polymers with balanced hole/electron mobilities(lh/le)and threshold voltages.Ambipolar polymers can be obtained by fine-tuning both the highest occupied molecular orbital(HOMO)and lowest unoccupied molecular orbital(LUMO)levels to match well with work function of Au electrodes(WF,4.7–5.2 eV)[5](Fig.S1a online).However,most polymers based on common acceptors only display unipolar(p-type or n-type)transport due to their wide bandgaps(>1.2 eV)and inappropriate energy levels[6].For example,isoindigo-based polymers generally show p-type semiconducting behaviors owing to their high-lying LUMO levels,which is unfavorable for electron injection(Fig.S1b online).
基金supported by the National Basic Research Program of China (Grant No.2007CB310407)Foundation for Innovative Research Groups of the NSFC (Grant No.61021061)+1 种基金the National Natural Science Foundation of China (Grant Nos.50972023 and 61071028)the International S&T Cooperation Program of China (Grant No.2006DFA53410)
文摘The conventional charge transport models based on density- and field-dependent mobility, only having a non-Arrhenius tem- perature dependence, cannot give good current-voltage characteristics of poly （2-methoxy-5-（2＇-ethylhexyloxy）-p-phenylene vinylene） （MEH-PPV） hole-only devices. In this paper, we demonstrate that the current-voltage characteristics can give a good unified description of the temperature, carrier density mad electric field dependence of mobility based on both the Arrhenius temperature dependence and the non-Arrhenius temperature dependence. Fu^hermore, we perform a systematic study of charge transport and electrical properties for MEH-PPV. It is shown that the boundary carrier density has an important effect on the current-voltage characteristics. Too large or too small values of boundary carrier density will lead to incorrect cur- rent-voltage characteristics. The numerically calculated carrier density is a decreasing function of the distance to the interface, and the numerically calculated electric field is an increasing function of the distance. Both the maximum of carrier density and the minimum of electric field appear near the interface.
