The nanowire gate-all-around structure with the ultimate channel electrostatic integrity exhibits the best immunity to short channel effects and improved scaling capability compared with other multigate structures. In this article, both the tunneling current and capacitance models are developed simultaneously for nanowire tunneling field-effect transistors (FETs). Based on the same surface potential model, the developed current model and capacitance model share the common parameters and therefore can be easily integrated as a complete model for circuit-level simulations. Moreover, there is no iterative process involved during the model derivation indicating the models would be efficient for circuit simulations. The proposed models are also implemented into a circuit simulator with SPICE net-list to simulate the inverter, NAND, and NOR gates. Correct circuit behaviors obtained validate the model compatibility with the SPICE platform and usefulness for the further investigation of nanowire-based tunnel FET (TFET) circuits. 

A Compact Model for Nanowire Tunneling-FETs

Role of Quasi-Fermi potential in modeling III-V TFETs: InAs as a case study


 The nanowire with gate-all-around (GAA) structure is widely considered as the most promising candidate for 3 nm technology with the best ability of suppressing the short channel effects and tunneling field effects transistors (TFETs) based on GAA structure also present improved performance. In this paper, a non-quasi-static (NQS) device model is developed for nanowire GAA TFETs. The model can predict the transient current and capacitance varied with operation frequency, which is beyond the ability of the already published quasi-static (QS) model. Excellent agreements between the model results and numerical simulations are obtained. Besides that, the NQS model is derived from the already proposed QS model including the current-voltage (I-V) and capacitance-voltage (C-V) characteristics. Therefore, the NQS model is compatible with the QS model for giving comprehensive understanding of GAA TFETs and would be helpful for the further study of TFET circuits based on nanowire GAA structure.

A Non-Quasi-Static Model for Nanowire Gate-All-Around Tunneling Field-Effects-Transistors

A Comprehensive Review on the Single Gate, Double Gate, Tri-Gate, and Heterojunction Tunnel FET for Future Generation Devices


 Due to the pristine interface of the 2D/3D face-tunneling heterostructure with an ultra-sharp doping profile, the 2D/3D TFET is considered as one of the most promising low-power devices that can simultaneously obtain low OFF-state current (I
 OFF), high ON-state current (I
 ON) and steep subthreshold swing (SS). As a key element for the 2D/3D TFET, the intensive exploration of the tunnel diode based on the 2D/3D heterostructure is in urgent need. The transfer technique composed of the exfoliation and the release process is currently the most common approach to fabricating the 2D/3D heterostructures. However, the well-established transfer technique of the 2D materials is still unavailable. Only a small part of the irregular films can usually be obtained by mechanical exfoliation, while the choice of the chemical exfoliation may lead to the contamination of the 2D material films by the ions in the chemical etchants. Moreover, the deformation of the 2D material in the transfer process due to its soft nature also leads to the nonuniformity of the transferred film, which is one of the main reasons for the presence of the wrinkles and the stacks in the transferred film. Thus, the large-scale fabrication of the high-quality 2D/3D tunnel diodes is limited. In this article, a comprehensive transfer technique that can mend up the shortages mentioned above with the aid of the water and the thermal release tape (TRT) is proposed. Based on the method we proposed, the MoS2/Si tunnel diode is experimentally demonstrated and the transferred monolayer MoS2 film with the relatively high crystal quality is confirmed by AFM, SEM, and Raman characterizations. Besides, the prominent NDR effect is observed at room temperature, which verifies the relatively high quality of the MoS2/Si heterojunction. The bilayer MoS2/Si tunnel diode is also experimentally fabricated by repeating the transfer process we proposed, followed by the specific analysis of the electrical characteristics. This study shows the advantages of the transfer technique we proposed and indicates the great application foreground of the fabricated 2D/3D heterostructure for ultralow-power tunneling devices.

MoS2/Si Tunnel Diodes Based on Comprehensive Transfer Technique

The combination of the InAs/GaSb heterojunction and the line-tunneling mechanism is considered as one of the most promising approaches to simultaneously obtain high ON-state current ( ${I}_{ \mathrm{\scriptscriptstyle ON}}$ ) and low subthreshold swing (SS) in tunneling field effect transistors (TFETs). However, in an InAs/GaSb line-tunneling field effect transistor (LTFET), the isolation between the source and the drain is a big issue. The leakage current path could lead to complete loss of the OFF-state characteristics in extreme cases. The “cantilever” or “airbridge” structure is usually introduced to cutoff the leakage path. However, it also induces serious reliability problems and brings additional process complexity. In this article, an N+ doped buried drain is first proposed to form a reverse biased p-n junction with the $\text{P}\boldsymbol +$ source and effectively cuts the leakage current path off. The InAs $\boldsymbol /$ GaSb LTFETs with this buried drain technique exhibits ${I}_{ \mathrm{\scriptscriptstyle ON}} \boldsymbol / {I}_{ \mathrm{\scriptscriptstyle OFF}} > {10}^{{7}}$ and SS $\boldsymbol /$ dec for five decades of current. Besides the excellent performance, the buried drain technique keeps the device planar and brings no additional fabrication complexity, which is of great significance for future experimental investigation and the low power applications.

Characteristics of InAs/GaSb Line-Tunneling FETs With Buried Drain Technique

The behavior of the magnetic field sensitivity of nitrogen-vacancy (NV) centers as a function of microwave power and the inhomogeneous distribution of MW fields was systematically studied. An optimal structure for exciting spin structures by MW signals was designed using two parallel loop antennas. The volume of the homogeneous regions was approximately 42 mm3, and the associated diameter of the diamond reached up to 5.2 mm with 1016 NV sensors. Based on this structure, the detection contrast and voltage fluctuation of an optically detected magnetic resonance (ODMR) signal were optimized, and the sensitivity was improved to 5 nT/√Hz. In addition, a pulse sequence was presented to fully eliminate the MW broadening. The magnetic field sensitivity was improved by approximately one order of magnitude as the π-pulse duration was increased to its coherence time. This offers a useful way to improve the sensitivity of spin-based sensors.

https://www.mdpi.com/2079-4991/12/22/3938/pdf?version=1668506301

Enhancing Spin-Based Sensor Sensitivity by Avoiding Microwave Field Inhomogeneity of NV Defect Ensemble

ETHNOPHARMACOLOGICAL RELEVANCE
The incidence of premature ovarian insufficiency (POI) is gradually increasing, the proportion is rising especially in female infertility patients. The risk of death of POI patients with cardiovascular disease also increases significantly. The cause of POI is complex and unclear, and clinical treatment is still in the exploratory stage, are two major constraints of treating POI. Traditional Chinese medicine (TCM) is widely used in the treatment of POI, and it is a good way to combine the development of modern new drugs with the help of TCM to predict the therapeutic targets.


AIM OF THE STUDY
In this study, four herbs commonly used in clinical treatment of POI, namely Radix Paeoniae, Polygonatum sibiricum, Rehmannia glutinosa and Eucommia ulmoides were selected to predict their mechanism in the treatment of POI, using network pharmacology methods. Then verify the predicted targets by animal test. Aim to find more effective POI potential core treatment targets and main pathways.


MATERIALS AND METHODS
We screened the active ingredients of drugs from the TCM System Pharmacology Analysis Platform (TCMSP), Performed target prediction of active ingredients from databases such as SwissTargetPrediction and compare and analyze the POI-related targets retrieved from them to obtain potential targets for drug treatment of POI. Used STRING database to construct a protein interaction network, Cytoscape 3.7.2 software to construct an active ingredient-target-pathway network, and DAVID database to conduct the Kyoto Encyclopedia of Genes and Genomes (KEGG) on the intersection targets and gene ontology (GO) enrichment analysis.


RESULTS
The result is: there were 25 key targets for the treatment of POI with Radix Paeoniae Alba, 31 for the treatment of POI by Eucommia ulmoides, 28 for the treatment of POI by Polygonatum sibiricum, and 8 key targets for the treatment of Rehmannia glutinosa. The intersection targets of four herbs were defined as the core targets, which are CYP19A1, EGF, ESR1, ESR2, MDM2, AR, PCYP17A1, PPARG. Four Chinese herbs treat POI mainly through HIF-1 signaling pathway, PI3K-Akt signaling pathway, FoxO signaling pathway, Estrogen signaling pathway etc. A mouse model of POI was constructed based on the results of network pharmacology to verify the predicted targets. The results showed that the protein expression of the core target changed, and the estrogen level was increased by reducing the expression of peroxisome proliferator-activated receptor gamma (PPARG).


CONCLUSIONS
This study predicts the mechanism of multiple herbs in the treatment of POI, screens out more potential therapeutic drug targets and main pathways of POI treatment and provides new ideas for the subsequent development of POI therapeutic drugs.

Aixin Guo

Papers

Characteristics of InAs/GaSb Line-Tunneling FETs With Buried Drain Technique

Enhancing Spin-Based Sensor Sensitivity by Avoiding Microwave Field Inhomogeneity of NV Defect Ensemble

Potential therapeutic drug targets and pathways prediction for premature ovarian insufficiency -Based on network pharmacologic method.