Inner Doping of Carbon Nanotubes with Perovskites for Ultralow Power Transistors.

Semiconducting carbon nanotubes (CNTs) are considered as the most promising channel material to construct ultrascaled field-effect transistors, but the perfect sp2 C─C structure makes stable doping difficult, which limits the electrical designability of CNT devices. Here, an inner doping method is developed by filling CNTs with 1D halide perovskites to form a coaxial heterojunction, which enables a stable n-type field-effect transistor for constructing complementary metal-oxide-semiconductor electronics. Most importantly, a quasi-broken-gap (BG) heterojunction tunnel field-effect transistor (TFET) is first demonstrated based on an individual partial-filling CsPbBr3/CNT and exhibits a subthreshold swing of 35 mV dec-1 with a high on-state current of up to 4.9 µA per tube and an on/off current ratio of up to 105 at room temperature. The quasi-BG TFET based on the CsPbBr3/CNT coaxial heterojunction paves the way for constructing high-performance and ultralow power consumption integrated circuits.

Aligned carbon nanotube-based electronics on glass wafer.

Carbon nanotubes (CNTs), due to excellent electronic properties, are emerging as a promising semiconductor for diverse electronic applications with superiority over silicon. However, until now, the supposed superiority of CNTs by "head-to-head" comparison within a well-defined voltage range remains unrealized. Here, we report aligned CNT (ACNT)-based electronics on a glass wafer and successfully develop a 250-nm gate length ACNT-based field-effect transistor (FET) with an almost identical transfer curve to a "90-nm" node silicon device, indicating a three- to four-generation superiority. Moreover, a record gate delay of 9.86 ps is achieved by our ring oscillator, which exceeds silicon even at a lower supply voltage. Furthermore, the fabrication of basic logic gates indicates the potential for further digital integrated circuits. All of these results highlight ACNT-based FETs on the glass wafer as an effective solution/platform for further development of CNT-based electronics.

Monolithic Three-Dimensional Integration of Carbon Nanotube Circuits and Sensors for Smart Sensing Chips.

Semiconducting carbon nanotube (CNT) film is a promising material for constructing high-performance complementary metal-oxide-semiconductor (CMOS) integrated circuits (ICs) and highly sensitive field-effect transistor (FET) bio/chemical sensors. Moreover, CNT logic transistors and sensors can be integrated through a compatible low-temperature fabrication process, providing enough thermal budget to construct monolithic three-dimensional (M3D) systems for smart sensors. However, an M3D sensing chip based on CNT film has not yet been demonstrated. In this work, we develop M3D technology to fabricate CNT CMOS ICs and CNT sensor arrays in two different layers; then, we demonstrate a preliminary M3D sensing system comprising CNT CMOS interfacing ICs in the bottom layer and CNT sensors in the upper layer through interlayer vias as links. As a typical example, a highly sensitive hydrogen sensing IC has been demonstrated to perform in situ sensing and processing functions through upper-layer FET-based hydrogen sensors exposed to the environment and bottom-layer CNT CMOS voltage-controlled oscillator (VCO) interfacing circuits. The M3D CNT sensing ICs convert hydrogen concentration information (8-128 ppm) to digital frequency information (0.78-1.11 GHz) with a sensitivity of 2.75 MHz/ppm. M3D sensing technology is expected to provide a universal sensing system for future smart sensing chips, including multitarget detection and ultralow power sensors.

Heavy Ion Displacement Damage Effect in Carbon Nanotube Field Effect Transistors.

Recent advances in carbon nanotube (CNT)-based integrated circuits have shown their potential in deep space exploration. In this work, the mechanism governing the heavy-ion-induced displacement damage (DD) effect in semiconducting single-walled CNT field effect transistors (FETs), which is one of the factors limiting device robustness in space, was first and thoroughly investigated. CNT FETs irradiated by a Xe ion fluence of 1012 ions/cm2 can maintain a high on/off current ratio, while transistors' performance failure is observed as the ion fluence increased to 5 × 1012 ions/cm2. Controllable experiments combined with numerical simulations revealed that the degradation mechanism changed as the nonionizing radiation energy built up. The trap generation in the gate dielectric, instead of the CNT channel, was identified as the dominating factor for the high-energy-radiation-induced device failure. Therefore, CNT FETs exhibited a >10× higher DD tolerance than that of Si devices, which was limited by the channel damage under irradiation. More importantly, the distinct failure mechanism determined that CNT FETs can maintain a high DD tolerance of 2.8 × 1013 MeV/g as the technology node scales down to 45 nm node, suggesting the potential of CNT-based VLSI for high-performance and high-robustness space applications.

Developmental, Dietary, and Geographical Impacts on Gut Microbiota of Red Swamp Crayfish (Procambarus clarkii).

Red swamp crayfish (Procambarus clarkii) breeding is an important economic mainstay in Hubei province, China. However, information on the gut microbiota of the red swamp crayfish is limited. To address this issue, the effect of developmental stage, diet (fermented or non-fermented feed), and geographical location on the gut microbiota composition in the crayfish was studied via high-throughput 16S rRNA gene sequencing. The results revealed that the dominant phyla in the gut of the crayfish were Proteobacteria, Bacteroidetes,Firmicutes, Tenericutes, and RsaHF231. The alpha diversity showed a declining trend during development, and a highly comparable gut microbiota clustering was identified in a development-dependent manner. The results also revealed that development, followed by diet, is a better key driver for crayfish gut microbiota patterns than geographical location. Notably, the relative abundance of Bacteroidetes was significantly higher in the gut of the crayfish fed with fermented feed than those fed with non-fermented feed, suggesting the fermented feed can be important for the functions (e.g., polysaccharide degradation) of the gut microbiota. In summary, our results revealed the factors shaping gut microbiota of the crayfish and the importance of the fermented feed in crayfish breeding.

Tin Selenide (SnSe): Growth, Properties, and Applications.

The indirect bandgap semiconductor tin selenide (SnSe) has been a research hotspot in the thermoelectric fields since a ZT (figure of merit) value of 2.6 at 923 K in SnSe single crystals along the b-axis is reported. SnSe has also been extensively studied in the photovoltaic (PV) application for its extraordinary advantages including excellent optoelectronic properties, absence of toxicity, cheap raw materials, and relative abundance. Moreover, the thermoelectric and optoelectronic properties of SnSe can be regulated by the structural transformation and appropriate doping. Here, the studies in SnSe research, from its evolution to till now, are reviewed. The growth, characterization, and recent developments in SnSe research are discussed. The most popular growth techniques that have been used to prepare SnSe materials are discussed in detail with their recent progress. Important phenomena in the growth of SnSe as well as the problems remaining for future study are discussed. The applications of SnSe in the PV fields, Li-ion batteries, and other emerging fields are also discussed.

High luminance hybrid light guide plate for backlight module application.

We introduce a hybrid backlight module, which consists of a hybrid light guide plate (HLGP) and a brightness enhancement film (BEF). The HLGP comprises functions of a conventional light guide plate, a reflector, and a BEF. The HLGP allows one-dimensional rays to be collimated. We add a BEF above the HLGP, and let the crossed-dimension rays to be collimated. Comparing with the conventional edge-lit backlight module, the optical efficiency improves to 1.3-times and the on-axis luminance improves to 3.7-times by using the hybrid backlight module.

Pregnancy outcome of women in the vicinity of nuclear power plants in Taiwan.

The purpose of the study was to investigate whether proximity to nuclear power plants may increase the risk of abnormal pregnant outcomes among the resident women. In this ecological study, data were used from the Health Services Birth Reports Database established by the Bureau of Health Promotion, National Department of Health, Taiwan, in 2001-2004. Chi-square-tests were carried out to investigate the "Plant-vicinity" and "Non plant-vicinity" group in terms of pregnancy outcome. Additionally, logistic regression was performed to investigate whether residence in the vicinity of a nuclear power plant was related to any abnormal pregnancy results. Based on data from 5,679 included subjects, no difference was observed between pregnancy outcomes of the "Plant-vicinity" and "Non plant-vicinity" groups. After accounting for possible confounders, the adjusted odds ratios were 1.20 (95% CI = 0.56-2.56) for stillbirth, 1.21 (95% CI = 0.95-1.53) for premature birth, 1.04 (95% CI = 0.79-1.37) for low birth weight, and 1.58 (95% CI = 0.85-2.93) for congenital deficiencies, respectively, when comparing the "Plant-vicinity" with the "Non plant-vicinity" group. The results of the study indicate that residence in the vicinity of a nuclear power plant is not a significant factor which will cause abnormal health situations during pregnancy.