Gated-MIS tunnel diode with ultrathin oxide has been proposed as a transconductance device. The on/off current ratio of a device is sensitive to oxide thickness. For thicker oxide, the on/off current ratio and transconductance sensitivity are inferior due to the lower oxide tunneling rate. In this work, a technique of utilizing the effective local thinning effect created by positive voltage stress (PVS), which only occurs with the oxide thickness larger than about 3 nm, is demonstrated to improve the on/off current ratio and transconductance sensitivity. After PVS, the on/off current ratio and transconductance sensitivity are strongly enhanced by the creation of an effective local thinning at the edge of the MIS(p) tunnel diode. A transconductance of 8.5 × 10−7 S was found in gated-MIS(p) tunnel diode operated at VTD = 0.5 V and VG ≅ −0.12 V after PVS treatment in contract to that of 1.8 × 10−10 S before PVS.

BACKGROUND The effect of hypoxia on mesenchymal stem cells (MSCs) is an emerging topic in MSC biology. Although long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) are reported to play a critical role in regulating the biological characteristics of MSCs, their specific expression and co-expression profiles in human placenta-derived MSCs (hP-MSCs) under hypoxia and the underlying mech anisms of lncRNAs in hP-MSC biology are unknown. AIM To reveal the specific expression profiles of lncRNAs in hP-MSCs under hypoxia and initially explored the possible mechanism of lncRNAs on hP-MSC biology. METHODS Here, we used a multigas incubator (92.5% N 2 , 5% CO 2 , and 2.5% O 2 ) to mimic the hypoxia condition and observed that hypoxic culture significantly promoted the proliferation potential of hP-MSCs. RNA sequencing technology was applied to identify the exact expression profiles of lncRNAs and mRNAs under hypoxia. RESULTS We identified 289 differentially expressed lncRNAs and 240 differentially expressed mRNAs between the hypoxia and normoxia groups. Among them, the lncRNA SNHG16 was upregulated under hypoxia, which was also validated by reverse transcription-polymerase chain reaction. SNHG16 was confirmed to affect hP-MSC proliferation rates using a SNHG16 knockdown model. SNHG16 overexpression could significantly enhance the proliferation capacity of hP-MSCs, activate the PI3K/AKT pathway, and upregulate the expression of cell cycle-related proteins. CONCLUSION Our results revealed the specific expression characteristics of lncRNAs and mRNAs in hypoxia-cultured hP-MSCs and that lncRNA SNHG16 can promote hP-MSC proliferation through the PI3K/AKT pathway.

In this work, two states phenomenon in the current-voltage behavior of metal-insulator-semiconductor (MIS) tunnel diode with ultra-thin SiO2 were investigated after negative/positive bias stress. The set state current is lower since the Schottky barrier height increases as electrons trap in the oxide at device edge. However, the positive read voltage leads to electron de-trapping, i.e., charge loss, and therefore the retention of MIS tunnel diode is inferior. In order to enhance the retention, the MIS TD coupled by the remote gate, i.e., gated-MIS TD, was proposed. Two gated-MIS TD’s with dielectric structures, SiO2 and Al2O3/HfO2/SiO2 (AHO) were investigated. By using the gate coupling structure, positive read voltage would not de-trap the trapped electrons directly, which reduced the disturbance due to reading.

In order to reduce the degradation caused by lateral non-uniformity (LNU) of gate oxides in metal-oxide-semiconductor (MOS) devices, a method to ameliorate the lateral oxide uniformity was proposed. By adopting the anodic oxidation compensation (ANO-compensation) technique to compensate the embedded aluminum layer, significant uniformity improvements were found in capacitance per unit area-voltage (C’-V) and current density-voltage (J-V) characteristics, and the percentage dispersions of capacitance per unit area and current density in accumulation regime also give the support to uniformity improvement. Besides, the outcomes of reliability tests also evidence that the LNU is reduced. Hence, with the advantages of superior oxide uniformity, the enhanced response in inversion capacitance was observed. At last, nitrate solution is used for validating the advantage of anodic oxidation compensation, and the J-V and C-V characteristics show that anodic oxidation compensation is necessary for fabricating reliable MOS-based devices.

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