the emergence of nanoscience and technology. Reviewing the history over the past 60 years, new devices based on new materials and new physics have been driving the development of integration circuits (ICs) along the Moore's law. Therefore, it has always been a frontier to explore new materials and novel physical properties that can help to push forward the development of ICs. In addition, currently, the multiple requirements for ICs are becoming increasingly important, such as flexible, transparent, and wearable. Just in this context, graphene, an ultrathin graphitic layer with a honeycomb structure, has aroused a wide attention since its discovery, which was demonstrated as a metallic transistor and proposed for high-frequency electronic circuits. [1] Due to its outstanding electronic, optical and mechanical properties, graphene was highly expected as a material to meet the increasing requirements for high-performance flexible, transparent and wearable electronic and optoelectronic devices. [2-8] The emergence of graphene inspired researchers to look for other 2D materials from van der Waals solids (VDWSs) since the one-atomic-layer graphene was revealed to be thermodynamically stable under ambient conditions. Up to now, 2D atomic crystals have been found in various VDWSs like hexagonal boron nitride (hBN), black phosphorus (BP), metal dichalcogenides (MDCs, like MoS 2 , WSe 2 , MoTe 2 , SnS 2 , and so on), and layered oxide, the basic of which can be seen in hundreds of reviews. [9-16] These graphene-like 2D materials are the thinnest crystals with the thickness usually less than 1 nm. They often exhibit distinctive properties different from conventional bulk materials. For example, bulk MoS 2 is of indirect bandgap but the monolayer is of direct one; [17,18] the bandgap of few layer semiconducting 2D layers often increases with the thickness decreasing, and can be modulated by electric field; [19-23] theoretical calculations indicate that the sunlight absorptivity of MDC monolayers like MoS 2 , MoSe 2 , and WS 2 is up to 5-10% that is 1 order higher than Si and GaAs, enabling them promising for ultrathin optoelectronic devices. [24] Besides, the 2D family covers a wide conductive range from metals, semimetals, semiconductors to insulators, offering a possibility to construct ultrathin devices totally based on 2D crystals. [25-27] And, as the study continues With the rise of 2D materials, new physics and new processing techniques have emerged, triggering possibilities for the innovation of electronic and optoelectronic devices. Among them, ambipolar 2D semiconductors are of excellent gate-controlled capability and distinctive physical characteristic that the major charge carriers can be dynamically, reversibly and rapidly tuned between holes and electrons by electrostatic field. Based on such properties, novel devices, like ambipolar field-effect transistors, lightemitting transistors, electrostatic-field-charging PN diodes, are developed and show great advantages in logic and reconfigurable circuits, integrate...

carrier mobility of the semiconductor channel drop sharply, the electrostatic gate control ability weak and the short channel effect prominent. [4][5][6] In such a case, the subthreshold slope (SS) of the devices will increase and the leakage current will become impressive, leading to non-negligible static power consumption. Therefore, it is very necessary to exploit new device structures and channel materials to effectively lower the SS and enhance the gate control ability to meet the needs of the low power consumption.As one of the emerging device structures, negative capacitance field-effect transistor (NC-FET) has attracted much attention. [7][8][9] It is achieved with a ferroelectric field-effect transistor (FeFET) device configuration, in which the dielectric is replaced by ferroelectric materials. The negative capacitance is realized by the polarization switch of the ferroelectric dielectric, which gives a chance to get steep SS to overcome the limit of 60 mV dec −1 (at room temperature) dominated by the Boltzmann distribution. [10][11][12] Up to now, many ferroelectric materials like organic poly(vinylidene difluoride-trifluoroethylene) [P(VDF-TrFE)] [13,14] and inorganic perovskite lead zirconate titanate (PZT) [15,16] have been successfully applied to NC-FETs. Recently, the discovery of ferroelectricity in Hf x Zr 1−x O 2 (HZO) further promotes the development in this field for its scalable thickness and compatibility with commercial semiconductor technology. [17][18][19] HZO has been currently applied to NC-FETs and shows the possibility to lower the SS far less than 60 mV dec −1 , indicating great potential for low-power integrated electronics. [18] To continue the effective electrostatic control in field-effect transistors (FETs), the channel semiconductor thickness should be less than the electrostatic screening length and one-third of the gate length. [20,21] On this point, 2D layered semiconductors are of obvious advantages, [22][23][24][25][26] which are the thinnest crystals (typically less than 1 nm) with excellent electronic properties, providing a possibility to push down the device feature size to even less than 3 nm without the loss of electrostatic control ability. [27,28] Among various 2D layered materials, ambipolar 2D semiconductors, like WSe 2 , are promising for electronic circuit design because of that both P-type and N-type transistors can be achieved in the same layer and easily homogeneously integrated for complementary metal oxide semiconductor (CMOS)

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Logic-in-memory architecture holds great promise to meet the high-performance and energy-efficient requirements of data-intensive scenarios. Two-dimensional compacted transistors embedded with logic functions are expected to extend Moore’s law toward advanced nodes. Here we demonstrate that a WSe2/h-BN/graphene based middle-floating-gate field-effect transistor can perform under diverse current levels due to the controllable polarity by the control gate, floating gate, and drain voltages. Such electrical tunable characteristics are employed for logic-in-memory architectures and can behave as reconfigurable logic functions of AND/XNOR within a single device. Compared to the conventional devices like floating-gate field-effect transistors, our design can greatly decrease the consumption of transistors. For AND/NAND, it can save 75% transistors by reducing the transistor number from 4 to 1; for XNOR/XOR, it is even up to 87.5% with the number being reduced from 8 to 1.