Selective doping of a single ambipolar organic semiconductor to obtain P- and N-type semiconductors

P- and N-dopable ambipolar bulk heterojunction thermoelectrics based on ladder-type conjugated polymers

“…It is worth noting that the p-and n-doped conductivities achieved at a 1 : 1 blend ratio were quite well-balanced, with considerably higher power factors as compared to the recently reported ambipolar conjugated polymer. 20 Taking advantage of the ambipolarity of the blend PBBTL: BBL film, we fabricate a full thermoelectric device consisting of single p-and n-channel legs using the PBBTL : BBL 1 : 1 ratio blend film as a proof of concept (Fig. 3a).…”

“…It is worth noting that the p- and n-doped conductivities achieved at a 1 : 1 blend ratio were quite well-balanced, with considerably higher power factors as compared to the recently reported ambipolar conjugated polymer. 20…”

“…Easier said than done, there is only one very recent report on an ambipolar conjugated polymer doped using p-and n-dopants for OTEs, achieving maximum p-and n-doped conductivities of 1.6 and 2.75 Â 10 À5 S cm À1 , respectively, and maximum power factors of B1 and B0.003 mW m À1 K À2 for p-and n-doping, respectively. 20 The lack of ambipolar conjugated polymers that can be both p-and n-doped is due to the frontier molecular orbital energy levels, i.e., the ambipolar conjugated polymer must have the suitable highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels that can be oxidized and reduced by the p-and n-dopants, respectively. Such a criterion will require the careful design of conjugated polymers, and the resulting polymers should also have balanced hole and electron transport properties.…”

Normally Off WSe2 Nanosheet-Based Field-Effect Transistors with Self-Aligned Contact Doping

“…10,11 In ambipolar field-effect transistors (FETs), the major transport carriers can be reversibly and intentionally altered between electrons and holes by applying an electrostatic field. 1,12,13 Thus, it can function as p-channels or n-channels selectively. Accordingly, the existing CMOS fabrication process, which comprises multiple ion implantation and subsequent activation annealing processes, can be greatly simplified.…”

“…As further scaling of silicon (Si) microelectronics reaches its fundamental limits, two-dimensional (2D) semiconductor materials have garnered considerable attention as post-Si channel layers owing to their excellent electrostatic control, dangling-bond-free smooth surface, and high carrier mobility . The 2D transition-metal dichalcogenide (TMD) semiconductors, including WSe 2 , WS 2 , MoS 2 , and MoTe 2 , have a thickness-dependent energy band gap with decent carrier mobility, which makes TMDs competitive over graphene as an ultrathin channel layer for next-generation high-performance nanoelectronic devices. − High-performance electronic (diodes and transistors) and optoelectronic (photodetectors and light-emitting diodes) devices based on TMD semiconductors have been demonstrated. − In particular, WSe 2 with band gap energy between 1.7 eV (direct, monolayer) and 1.2 eV (indirect, multilayer) is an intriguing semiconductor material, primarily because it has ambipolar transport properties (electron mobility ∼250 cm 2 /V·s and hole mobility ∼270 cm 2 /V·s) that have the potential to replace the existing silicon complementary metal-oxide semiconductor (CMOS) architecture which requires both enhancement-mode n-channel and p-channel transistors. , In ambipolar field-effect transistors (FETs), the major transport carriers can be reversibly and intentionally altered between electrons and holes by applying an electrostatic field. ,, Thus, it can function as p-channels or n-channels selectively. Accordingly, the existing CMOS fabrication process, which comprises multiple ion implantation and subsequent activation annealing processes, can be greatly simplified. , Consequently, the footprint of the CMOS device architectures can be scaled.…”