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In this letter, a 125 to 143 GHz frequencyreconfigurable BiCMOS compact low-noise amplifier (LNA) is presented for the first time. It consists of two cascode stages and was fabricated using a 0.13-µm SiGe:C BiCMOS process which integrates RF-MEMS switches. A systematic general design procedure to obtain a balanced gain and noise figure in both frequency states is proposed. The LNA size is minimized by using only one RF-MEMS switch to select the frequency band and a multimodal three-line microstrip structure in the input matching network. The measured gain and noise figure are 18.2/16.1 dB and 7/7.7 dB at 125/143 GHz. The power consumption is 36.8 mW. Measured results are in good agreement with simulations. Index Terms-frequency-reconfigurable LNA, multimodal circuit, RF-MEMS switch.

Thousands of high-performance 2D MOSFETs were fabricated on wafer-scale chemical vapor deposited MoS2 with fully-CMOS-compatible processes such as photolithography and aluminum metallurgy. The yield was greater than 50% in terms of effective gate control with less-than-10 V threshold voltage, even for MOSFETs having deep-submicron gate length. The large number of fabricated MOSFETs allowed statistics to be gathered and the main yield limiter to be attributed to the weak adhesion between the transferred MoS2 and the substrate. With cut-off frequencies approaching the gigahertz range, the performances of the MOSFETs were comparable to that of state-of-the-art MoS2 MOSFETs, whether the MoS2 was grown by a thin-film process or exfoliated from a bulk crystal.

We investigate the use of perfluorodecyltrichlorosilane-based self-assembled monolayer as seeding layer for chemical vapour deposition of HfO2 on large area CVD graphene. The deposition and evolution of the FDTS-based seed layer is investigated by X-ray photoelectron spectroscopy, Auger electron spectroscopy, and transmission electron microscopy. Crystalline quality of graphene transferred from Cu is monitored during formation of the seed layer as well as the HfO2 growth using Raman spectroscopy. We demonstrate that FDTS-based seed layer significantly improves nucleation of HfO2 layers so that graphene can be coated in a conformal way with HfO2 layers as thin as 10 nm. Proof-of-concept experiments on 200 mm wafers presented here validate applicability of the proposed approach to wafer scale graphene device fabrication.