Achieving multifunctional van der Waals nanoelectronic devices on one structure is essential for the integration of 2D materials; however, it involves complex architectural designs and manufacturing processes. Herein, a facile, fast, and versatile laser direct write micro/nanoprocessing to fabricate diode, NPN (PNP) bipolar junction transistor (BJT) simultaneously based on a pre‐fabricated black phosphorus/molybdenum disulfide heterostructure is demonstrated. The PN junctions exhibit good diode rectification behavior. Due to different carrier concentrations of BP and MoS2, the NPN BJT, with a narrower base width, renders better performance than the PNP BJT. Furthermore, the current gain can be modulated efficiently through laser writing tunable base width WB, which is consistent with the theoretical results. The maximum gain for NPN and PNP is found to be ≈41 (@WB≈600 nm) and ≈12 (@WB≈600 nm), respectively. In addition, this laser write processing technique also can be utilized to realize multifunctional WSe2/MoS2 heterostructure device. The current work demonstrates a novel, cost‐effective, and universal method to fabricate multifunctional nanoelectronic devices. The proposed approach exhibits promise for large‐scale integrated circuits based on 2D heterostructures.

van der Waals p-n heterostructures based on p-type black phosphorus (BP) integrated with other two-dimensional (2D) layered materials have shown potential applications in electronic and optoelectronic devices, including logic rectifiers and polarization-sensitive photodetectors. However, the engineering of carriers transport anisotropy, which is related to the linear dichroism, have not yet been investigated. Here, we demonstrate a novel van der Waals device of orientation-perpendicular BP homojunction based on the anisotropic band structures between the armchair and zigzag directions. The structure exhibits good gate-tunable diode-like rectification characteristics caused by the barrier between the two perpendicular crystal orientations. Moreover, we demonstrate that the unique mechanisms of the polarization-sensitivity properties of this junction are involved with the linear dichroism and the anisotropic carriers transport engineering. These results were verified by the scanning photocurrent images experiments. This work paves the way for 2D anisotropic layered materials for next-generation electronic and optoelectronic devices.

We investigate the photoexcited–carrier dynamics and coherent acoustic phonon oscillations in mechanically exfoliated PdSe2 flakes with a thickness ranging from 10.6 nm to 54 nm using time-resolved transient reflection spectroscopy.

Seeking controllable and efficient surface dopant molecules for transition‐metal dichalcogenides (TMDCs) is highly valuable for fully understanding TMDCs properties and their applications to relevant devices. The general doping effect of solvents on TMDCs are explored. By selecting suitable solvents with optimized relevant factors, controllable n‐doping of molybdenum disulfide (MoS2) is obtained on the same device with the sheet density of electrons increased from 2.3 × 1011 to 6.4 × 1012, 9.7 × 1012, and 1.6 × 1013 by use of dimethylsulfoxide, N,N‐dimethylformamide, and N‐methyl‐pyrrolidone (NMP), respectively. The doping principle is explained by charge‐donating characteristics of molecule and dipole interaction. After doping by NMP, the contact resistance is reduced by four times, and the on/off current ratio of fabricated top‐gated MoS2 transistors is increased by 3 orders of magnitude. This work can guide the selection of suitable solvents for effective doping of two‐dimensional materials and advance the development of precise controllable electronic and optoelectronic devices.

A bipolar junction transistor with good amplification output and gate tunable photocurrent gain has been conveniently fabricated by femtosecond laser processing.