Stacked SiGe nanosheets p-FET for Sub-3 nm logic applications.

The fabrication of vertically stacked SiGe nanosheet (NS) field-effect transistors (FETs) was demonstrated in this study. The key process technologies involved in this device fabrication are low pressure chemical vapor deposition SiGe/Si multilayer epitaxy, selective etching of Si layers over SiGe layers using tetramethyl-ammonium-hydroxide wet solution, and atomic layer deposition of Y2O3 gate dielectric. For the fabricated stacked SiGe NS p-GAAFETs with a gate length of 90 nm, ION/IOFF ratio of around 5.0 × 105 and subthreshold swing of 75 mV/dec were confirmed via electrical measurements. Moreover, owing to its high quality of Y2O3 gate dielectric, the device showed a very small drain-induced barrier-lowering phenomenon. These designs can improve the gate controllability of channel and device characteristics.

High-Performance P- and N-Type SiGe/Si Strained Super-Lattice FinFET and CMOS Inverter: Comparison of Si and SiGe FinFET.

This research presents the optimization and proposal of P- and N-type 3-stacked Si0.8Ge0.2/Si strained super-lattice FinFETs (SL FinFET) using Low-Pressure Chemical Vapor Deposition (LPCVD) epitaxy. Three device structures, Si FinFET, Si0.8Ge0.2 FinFET, and Si0.8Ge0.2/Si SL FinFET, were comprehensively compared with HfO2 = 4 nm/TiN = 80 nm. The strained effect was analyzed using Raman spectrum and X-ray diffraction reciprocal space mapping (RSM). The results show that Si0.8Ge0.2/Si SL FinFET exhibited the lowest average subthreshold slope (SSavg) of 88 mV/dec, the highest maximum transconductance (Gm, max) of 375.2 µS/µm, and the highest ON-OFF current ratio (ION/IOFF), approximately 106 at VOV = 0.5 V due to the strained effect. Furthermore, with the super-lattice FinFETs as complementary metal-oxide-semiconductor (CMOS) inverters, a maximum gain of 91 v/v was achieved by varying the supply voltage from 0.6 V to 1.2 V. The simulation of a Si0.8Ge0.2/Si super-lattice FinFET with the state of the art was also investigated. The proposed Si0.8Ge0.2/Si strained SL FinFET is fully compatible with the CMOS technology platform, showing promising flexibility for extending CMOS scaling.

Application of Tivantinib for Hepatocellular Carcinoma: A Meta-Analysis Study.

Objectives: The efficacy of tivantinib may have some potential in treating MET-high hepatocellular carcinoma, and we aim to compare tivantinib with placebo for the treatment of MET-high hepatocellular carcinoma. Methods: Several databases including PubMed, Cochrane Library, Web of Science, EBSCO, and EMbase have been systematically searched through March 2022, and we included studies regarding the treatment of MET-high hepatocellular carcinoma by using tivantinib versus placebo. Results: We finally include three RCTs. In comparison with placebo for MET-high hepatocellular carcinoma, tivantinib reveals no significant influence on overall survival (P=0.21), progression-free survival (P=0.13), time to progression (P=0.38), or grade ≥3 anemia (P=0.50) but increases the incidence of grade ≥3 neutropenia (P=0.04). Conclusions: Tivantinib may provide no additional benefits for MET-high hepatocellular carcinoma.

Decreased Event-Related Desynchronization of Mental Rotation Tasks in Young Tibetan Immigrants.

The present study aimed to explore the cortical activity underlying mental rotation in high-altitude immigrants via the event-related desynchronization (ERD), the electroencephalogram time-frequency analysis, and source localization based on electroencephalographic data. When compared with the low-altitude individuals, the reaction time of mental rotation tasks was significantly slower in immigrants who had lived in high-altitude areas for 3 years. The time-frequency analysis showed that the alpha ERD and the beta ERD within the time window (400-700 ms) were decreased during the mental rotation tasks in these immigrants. The decreased ERD was observed at the parietal-occipital regions within the alpha band and at the central-parietal regions within the beta band. The decreased ERD might embody the sensorimotor-related cortical activity from hypoxia, which might be involved in cognitive control function in high-altitude immigrants, which provided insights into the neural mechanism of spatial cognition change on aspect of embodied cognition due to high-altitude exposure.

[Value of Serum Light Chain in Diagnosis and Evaluation of Efficacy for Multiple Myeloma].

OBJECTIVE: To explore the clinical application value of serum light chain (sLC) in the diagnosis and therapeutic efficacy evaluation for multiple myeloma. METHODS: 46 patients with newly diagnosed multiple myeloma were selected as MM group and 50 healthy persons as control group. Rate scattering immunoturbidimetry was used to detect serum light chain and immunoglobulin (Ig) in two groups, serum protein electrophoresis was used to detect M protein by agarose gel. Then, the sensitivity and specificity of the two methods in MM diagnosis were analyzed and compared, and the significance of sLC detection in MM diagnosis were discussed. In addition, 15 MM patients after received conventional therapy were tracked, sLC levels in five different therapentic times were recorded, and the effect of sLC in efficacy evaluation of MM was analyzed. RESULTS: There were 11 cases of IgA type, 15 cases of IgG type, 8 cases of light chain κ type, 8 cases of light chain λ type, 2 cases of IgD type, and 2 cases of non-secretion type. The sLC-κ, sLC-λ and their ratio (including light chain type and double clone type), IgA and IgG (except IgD type), as well as albumin, beta-globulin and gamma-globulin levels showed statistically significant differences (P＜0.05) compared with the control group. The sensitivity of serum protein electrophoresis, Ig quantification, sLC and its ratio in the diagnosis of multiple myeloma were 57%, 76% and 65%, and their specificity were 83%, 61% and 90%, respectively. After the second or third chemotherapy, the sLC-κ/λ ratio gradually approached the normal range as the disease reliefes, and the sLC-κ/λ ratio continued to be on or off the line at outliers or further away from the reference value as the disease progresses in MM patients with κ type or λ type. CONCLUSION: sLC detection shows positive significance in early diagnosis of multiple myeloma, SLC monitoring can be used for the efficacy evaluation for treatment of MM patients.

Microwave Annealing for NiSiGe Schottky Junction on SiGe P-Channel.

In this paper, we demonstrated the shallow NiSiGe Schottky junction on the SiGe P-channel by using low-temperature microwave annealing. The NiSiGe/n-Si Schottky junction was formed for the Si-capped/SiGe multi-layer structure on an n-Si substrate (Si/Si0.57Ge0.43/Si) through microwave annealing (MWA) ranging from 200 to 470 °C for 150 s in N2 ambient. MWA has the advantage of being diffusion-less during activation, having a low-temperature process, have a lower junction leakage current, and having low sheet resistance (Rs) and contact resistivity. In our study, a 20 nm NiSiGe Schottky junction was formed by TEM and XRD analysis at MWA 390 °C. The NiSiGe/n-Si Schottky junction exhibits the highest forward/reverse current (ION/IOFF) ratio of ~3 × 105. The low temperature MWA is a very promising thermal process technology for NiSiGe Schottky junction manufacturing.

Effect of surface Si redistribution on the alignment of Ge dots grown on pit-patterned Si(001) substrates.

Thermally activated redistribution of Si surface atoms is found to be a crucial factor for the growth of aligned Ge dots on pit-patterned Si(001) substrates. A phenomenon of Si accumulation around the edge of pits significantly alters the substrate surface morphology. As the pit spacing is reduced to below 100 nm, a convex morphology developed between adjacent pits causes a chemical potential distribution that drives the Ge dots into the pits. In addition, the pits of an etching depth greater than 60 nm will evolve into truncated inverted pyramids with sharp base corners that provide deep potential wells for the confinement of Ge dots. Perfectly aligned Ge dots are obtained on pit-patterned Si substrates with this range of pit spacing and etching depth. We also find that the initial geometric shape of the pits does not affect the spatial arrangement of Ge dots.

Thermally induced morphology evolution of pit-patterned Si substrate and its effect on nucleation properties of Ge dots.

We demonstrate the effect of the pre-growth heat treatment process on the nucleation properties of Ge dots grown on pit-patterned Si(001) substrates. The prefabricated 200 nm diameter pits inherently evolve into truncated inverted pyramids (TIPs) with (110) base edges and a 7°-9° sidewall slope during heat treatment; this morphology transformation is robust against variations in shape and orientation of the pit patterns. Uniform Ge dots with an areal density of 4 × 10(9) cm(-2) were obtained on the Si substrates having TIPs. Each TIP contains four aligned Ge dots locating symmetrically with respect to (110). These dots exhibit an elliptical dome shape with major axis oriented along (100). The nucleation position, shape and spatial orientation of these Ge dots coincide with the calculated surface chemical potential distribution of the TIP.