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III-V compound semiconductors are widely used for electronic and optoelectronic applications. However, interfacing III-Vs with other materials has been fundamentally limited by the high growth temperatures and lattice-match requirements of traditional deposition processes. Recently, we developed the templated liquid-phase (TLP) crystal growth method for enabling direct growth of shape-controlled single-crystal III-Vs on amorphous substrates. Although in theory, the lowest temperature for TLP growth is that of the melting point of the group III metal (e.g., 156.6 °C for indium), previous experiments required a minimum growth temperature of 500 °C, thus being incompatible with many application-specific substrates. Here, we demonstrate low-temperature TLP (LT-TLP) growth of single-crystalline InP patterns at substrate temperatures down to 220 °C by first activating the precursor, thus enabling the direct growth of InP even on low thermal budget substrates such as plastics and indium-tin-oxide (ITO)-coated glass. Importantly, the material exhibits high electron mobilities and good optoelectronic properties as demonstrated by the fabrication of high-performance transistors and light-emitting devices. Furthermore, this work may enable integration of III-Vs with silicon complementary metal-oxide-semiconductor (CMOS) processing for monolithic 3D integrated circuits and/or back-end electronics.

As tellurides and selenides of Bismuth are extensively used thermoelectric materials in the low-temperature range with refrigeration application, A concerted effort is put forth to boost the ZT by co-doping the pristine Bi2Se3 with antimony (Sb) on cation end and tellurium (Te) on anion side of the compound. The double sintered solid-state reaction method is employed in the preparation of Bi2Se3 and (Bi1−xSbx)2Se2.7Te0.3 polycrystalline pellets, with x = 0.02, 0.04, and 0.06. The sample exhibits a rhombohedral structure with the space group of R 3 ¯ m. FESEM and EDAX analysis are used to confirm surface morphology and elemental composition of the produced samples. The thermoelectric measurements for the pristine and co-doped samples were conducted by the physical property measurement system as well as a considerable increase in the Seebeck coefficient of − 115 µV/K is observed for 0.02 doping of the Sb which is 4.2 times greater than as for pristine (S = − 28 µV/K). Higher concentration doping (x = 0.04, 0.06) has not reflected any Seebeck coefficient advancement. In contrast, the lowest total thermal conductivity at a low-temperature regime (< 50 K) is observed for x = 0.06 doping concentration which at near room temperature increases beyond the pristine thermal conductivity; whereas, x = 0.02, 0.04 doping concentration shows a decrement in total thermal conductivity at low, at room temperature region the values are almost equivalent to that of pristine. The co-doped samples' electrical resistivity is substantially less than pristine sample. The highest power factor of 3 × 10–4 µW/mK2 is obtained for the x = 0.02 sample. The highest ZT value for the x = 0.02 sample is almost 28 times more than a pristine sample. We conducted a study where we combined experimental and DFT methods to investigate thermoelectric properties incorporated into pristine and doped with antimony and tellurium on Bi2Se3. We have employed this combination to investigate the partial density of states, Seebeck coefficient, power factor using the Boltzmann transport equation. Theoretical thermoelectric data were derived and compared to experimental observations. Hence, using combined experimental and theoretical investigations helps to predict with higher accuracy of thermoelectric properties of semiconducting materials. [ABSTRACT FROM AUTHOR]

This study proposes a panel smooth transition regression (PSTR) model to investigate the nonlinear relationship between crude oil prices and crude oil production in 122 countries, both OPEC and non-OPEC, from March 1994 to October 2015. The statistical test for the existence of a threshold effect indicates that the relationship between oil prices and oil production is nonlinear, with different changes over time among the oil price and transition variables. Additionally, a threshold value exists. Furthermore, crude oil price volatility exhibits asymmetric responses to production volatility by fluctuating above or below the threshold value. Finally, when crude oil price volatility with a lag of two periods exceeds the threshold value, crude oil production changes have a positive impact on crude oil price volatility. In contrast, when crude oil price volatility with a lag of two periods is less than the threshold value, crude oil production changes have a negative impact on price volatility.

Owing to the increasing demand for monitoring harmful toxic gases using small‐sized low‐power‐consumption gas sensors, a room‐temperature wireless complimentary gas sensor incorporating layered materials is proposed and demonstrated. The compact design allows the sensing module to be installed under all conditions and facilitates multiple detections of toxic gas. Highly chemical‐resistance‐sensitive materials based on n‐type SnSe2 and p‐type PtSe2 layered materials prepared by the plasma‐assisted chemical vapor reaction (PACVR) method at low temperatures are integrated with an oscillation circuit and antenna fabricated by a 28‐nm CMOS high‐k metal gate logic process to achieve dense, low‐powered, and wireless characteristics. By pairing n‐ and p‐type layered semiconductors, the gas sensors feature less influence from the surroundings, such as temperature and humidity, and enhance sensitivity to the target gas simultaneously. The wireless sensing detection method enables a sensor to make signal reception more convenient. Furthermore, a wireless gas sensor with self‐converging calibration using the advantage of a floating‐gate (FG) transistor to control the charge quantity by shifting the threshold voltage (Vth) of each transistor via the channel hot electron injection effect, which helps to reduce the impact of process variations, minimizing readout errors, is proposed. [ABSTRACT FROM AUTHOR]

A top‐down transfer process is developed via a rolling process associated with thermal release tape/poly(methyl methacrylate) (PMMA) bi‐supporting layers to realize large‐scale transfer processes on transition metal dichalcogenide materials. A 2‐inch MoS2 thin film transferred on SiO2/Si substrates with high integrity and a yield of ≈99% can be successfully achieved via the proposed process. MoS2‐based transistors with a transferred Au thin film as the contact electrode indicate a lower contact resistance of 8.4 kΩ with improved mobility and a higher on/off ratio compared with that of the MoS2‐based transistors with the evaporated Au thin film as the contact electrode. By applying the difference in adhesion force between metal oxides and metal on MoS2 and PMMA surfaces, the selective transfer of MoS2 films can be demonstrated. Furthermore, all‐transferred MoS2‐based transistor arrays are demonstrated by combining the selectively transferred MoS2 film as the channel material and the transferred Au thin films as the contact electrode, which results in uniform electrical properties featuring a carrier mobility of 10.45 cm2 V−1 s−1, a subthreshold swing of 203.94 mV dec−1, a normalized Ion of 8.3 μA μm−1, and an on/off ratio of 105. [ABSTRACT FROM AUTHOR]

Herein, oxygen‐incorporated 2D‐SnSe2 layered films are successfully fabricated by a plasma‐assisted selenization process. The oxygen concentrations inside the 2D‐SnSe2 layered film are controllable by controlling the proportion of hydrogen in the mixed gas of nitrogen and hydrogen during the plasma‐assisted selenization reaction. Oxygen atoms mainly exist in the form of the incorporated oxygen in the 2D‐SnSe2 layered film with an exceedingly small grain size of SnO2, which significantly increases the total interface area of the SnO2/SnSe2. Significant enhancement of the gas response to NO2 (709% under 100 ppb NO2) is reached when the proportion of hydrogen during the plasma‐assisted selenization process is 25%, thus showing excellent sensitivity and selectivity. Moreover, the sensor also demonstrated excellent stability under an increase in relative humidity. It is verified that the response will not significantly decrease when the relative humidity is below 90%. The obtained results demonstrate that oxygen‐incorporated 2D‐SnSe2 layered film with excellent commercial potential, is a highly suitable candidate for next‐generation gas sensors. [ABSTRACT FROM AUTHOR]

Tuberculous peritonitis (TBP) is a rare but fatal complication in patients on peritoneal dialysis (PD). In this study, we aimed to determine the demographic features, clinical features, laboratory parameters, and clinical outcomes of PD patients with TBP and to clarify possible risk factors for mortality. We retrospectively reviewed 2084 PD patients from January 1985 to December 2019. The diagnosis of TBP was established by positive peritoneal fluid culture for Mycobacterium tuberculosis. 18 patients were diagnosed with TBP. The incidence was 2.029 episodes per 1000 patient-years. The most common symptom was fever (94.4%), followed by cloudy effluent (83.3%) and abdominal pain (83.3%). The average peritoneal dialysis effluent (PDE) white blood cell (WBC) count was 172.7 cells/μL. Nine patients (50%) had WBC counts lower than 100 cells/μL and 13 patients (72.2%) had neutrophilic predominant WBC counts. Acid fast stain (AFS) was positive in 7 patients (38.9%). Only 2 patients (11.1%) continued with PD after TB infection, while 10 patients (55.6%) changed to hemodialysis. Seven patients (38.9%) died within 1 year. Significant differences were observed in sex (p = 0.040), the presence of diabetes mellitus (p = 0.024), and PD catheter removal (p < 0.001) between TBP patients with and without mortality. However, none of them was a significant factor for 1-year mortality in multivariate Cox regression model. Physicians should pay attention to the unusual presentations of peritonitis, especially if symptoms include fever or an initial low PDE WBC count. Catheter removal is not mandatory if early diagnosis and appropriate therapy are available. [ABSTRACT FROM AUTHOR]