Phase-Engineered Molybdenum Telluride/Black Phosphorus Van der Waals Heterojunctions for Tunable Multivalued Logic

Abstract

Recently, multivalued logic (MVL) circuits have attracted tremendous interest due to their ability to process more data by increasing the number of logic states rather than the integration density. Here, we fabricate logic circuits based on molybdenum telluride (MoTe2)/black phosphorus (BP) van der Waals heterojunctions with different structural phases of MoTe2. Owing to the different electrical properties of the 2H and mixed 2H +1T′ phases of MoTe2, tunable logic devices have been realized. A logic circuit based on a BP field-effect transistor (FET) and a BP/MoTe2 (2H + 1T′) heterojunction FET displays the characteristics of binary logic. However, a drain voltage-controlled transition from binary to ternary logic has been observed in BP FET- and BP/ MoTe2 (2H) heterojunction FET-based logic circuits. Also, a change from binary to ternary characteristics has been observed in BP/MoTe2 (2H)-based inverters at low temperature below 240 K. We believe that this work will stimulate the assessment of the structural phase transition in metal dichalcogenides toward advanced logic circuits and offer a pathway to substantialize the circuit standards for future MVL systems.

Gate‐Switchable Photovoltaic Effect in BP/MoTe2 van der Waals Heterojunctions for Self‐Driven Logic Optoelectronics

“…Different from the previously reported works, [15][16][17][18]21] the logic switch of this device relies on the modulation of the photovoltaic effect in the BP/MoTe 2 heterojunction. Thanks to the ambipolar conduction characteristics of the BP and MoTe 2 , [22][23][24] the BP/MoTe 2 heterojunction can be tuned to anisotype (p-N) and isotype (p-P and n-N) by the gate voltage for reconfiguring the photovoltaic effect. Meanwhile, the photovoltaic effect converts optical signals into current signals without external bias, which has been proven to be a practical and sustainable self-driven solution for low-energy consumption optoelectronic devices.…”

Hybrid Thin-Film Materials Combinations for Complementary Integration Circuit Implementation

“…By employing various semiconductors that possess different types of major carriers with each other, the CMOS has overcome many limitations in terms of fabrication processes and device performance enhancement. Furthermore, in some trials, an n-p heterojunction transistor was utilized instead of one of the transistors in the CMOS, which showed a reversed ambipolar I-V curve [26,111]. The integrated inverter produces the third state of "1/2" excluding "1" and "0" at the voltage transport curve, which is called a ternary inverter.…”

The Art of Constructing Black Phosphorus Nanosheet Based Heterostructures: From 2D to 3D

“…Building van der Waals heterostructures with other 2D materials, such as graphene or h-BN, can prevent the degradation of BPNSs and stabilize them in ambient conditions for high-performance transistors. [134][135][136][137][138][139][140][141][142][143][144]…”