Fixed-Current Operation of a VCSEL Transmitter Over a Temperature Range From ${-} 20^{\circ}$C to 80$^{\circ}$C Using an Elevated-Oxide-Layer Structure

2011 ◽  
Vol 29 (24) ◽  
pp. 3817-3823
Author(s):  
Taeyong Kim ◽  
Sungil Kim ◽  
Min Hwan Kwak ◽  
Seung Beom Kang ◽  
Kwang-Yong Kang ◽  
...  
Keyword(s):  
Oxide Layer ◽  
Layer Structure ◽  
Temperature Range ◽  
Current Operation

Ignition model of boron particle based on the change of oxide layer structure

2019 ◽  
Vol 37 (3) ◽  
pp. 3033-3044 ◽  
Author(s):  
Xu Hu ◽  
Yihua Xu ◽  
Wen Ao ◽  
Zhuoxiong Zeng ◽  
Chunbo Hu ◽  
...  
Keyword(s):  
Oxide Layer ◽  
Layer Structure ◽  
Boron Particle

Manipulation of Germanium Nanocrystals in a Tri-Layer Insulator Structure of a Metal-Insulator-Semiconductor Memory Device

2002 ◽  
Vol 728 ◽  
Author(s):  
L.W. Teo ◽  
C.L. Heng ◽  
V. Ho ◽  
M. Tay ◽  
W.K. Choi ◽  
...  
Keyword(s):  
Silicon Dioxide ◽  
Oxide Layer ◽  
Layer Structure ◽  
Charge Trapping ◽  
Middle Layer ◽  
Memory Device ◽  
Metal Insulator ◽  
Metal Insulator Semiconductor ◽  
20 Nm ◽  
Ge Nanocrystals

AbstractA metal-insulator-semiconductor (MIS) device that consists of germanium (Ge) nanocrystals embedded in a novel tri-layer insulator structure is proposed for memory applications [1]. The tri-layer structure comprises a thin (≈5nm) rapid thermal oxidation (RTO) silicon dioxide (SiO2) layer, a Ge+SiO2 middle layer (6 - 20 nm) deposited by RF co-sputtering technique and a RF-sputtered silicon dioxide capping layer. High-resolution transmission electron microscopy (HRTEM) results show that Ge nanocrystals of sizes ranging from 6 –20 nm were found after rapid thermal annealing of the trilayer structure at 1000°C for 300s. The electrical properties of these devices have been characterized using capacitance versus voltage (C-V) measurements. A significant hysteresis was observed in the C-V curves of these devices, indicating charge trapping in the composite insulator. Comparison with devices having similar tri-layer insulator structure, but with a pure sputtered oxide middle layer (i.e. minus the Ge nanocrystals), clearly indicated that the observed charge trapping is due to the presence of the Ge nanocrystals in the middle layer. The C-V measurements of devices without the capping SiO2 layer exhibited no significant hysteresis as compared to the embedded Ge nanocrystal tri-layer devices. The HRTEM micrographs showed that the presence of the capping oxide is critical in the formation of nanocrystals for this structure. By varying the thickness of the middle layer, it was found that the maximum nanocrystal size correlates well with the middle layer thickness. This indicates that the nanocrystals are well confined by the RTO oxide layer and the capping oxide layer. In addition, Ge nanocrystals formed using a thinner middle layer were found to be relatively uniform in size and distribution. This structure, therefore, offers a possibility of fabricating memory devices with controllable Ge nanocrystals size.

Research on the Microstructure and the Growth Mechanism of Oxidation Film of T91 Steels after Service

2012 ◽  
Vol 476-478 ◽  
pp. 144-150
Author(s):  
Wan Li Zhong ◽  
Zheng Gang Li ◽  
Wei Wang ◽  
Bing Yang
Keyword(s):  
Oxide Layer ◽  
Transition Zone ◽  
Layer Structure ◽  
Alloy Element ◽  
Testing Methods ◽  
Intergranular Oxidation ◽  
Double Layer Structure ◽  
Superheater Tube ◽  
Outer Oxide Layer ◽  
Original Metal

The character of structure and the micro-area elements of inner oxidation film were investigated by using metallographic microscope, electron microscopy, energy spectrum analysis and other testing methods based on samples of superheater and reheater tube cutting from three units. The results showed that the inner wall oxide layer of T91 steel superheater tube after running exhibited a double-layer structure, including inner and outer layer, and the interface between the two layers is the original metal surface. There exists a transition zone between the inner oxide film and metal matrix. A concentration gradient of alloy element in transition zone can be observed and the intergranular oxidation is present. The Fe-rich outer oxide layer does not contain Cr, which consists of Fe3O4, and the internal oxidation layer is composed of (Fe,Cr)3O4.

scholarly journals Effects of Hydrogen Contents on Oxidation Behavior of Alloy 690TT and Associated Boron Accumulation within Oxides in High-Temperature Water

Scanning ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-12
Author(s):  
Soon-Hyeok Jeon ◽  
Geun Dong Song ◽  
Do Haeng Hur
Keyword(s):  
High Temperature ◽  
Oxide Layer ◽  
Photoelectron Spectroscopy ◽  
Intermediate Layer ◽  
Layer Structure ◽  
Boron Compounds ◽  
Oxide Layers ◽  
Outermost Layer ◽  
High Temperature Water ◽  
Temperature Water

The aim of this work is to characterize the oxide layer structure of Alloy 690TT in high-temperature water with different dissolved hydrogen (DH) contents by using an X-ray photoelectron spectroscopy. Under the low DH contents (0.4494–0.8988 mg/kg), the oxide layers were composed of an outermost layer of Ni(OH)2 and Cr(OH)3 enriched in Ni, an intermediate layer of hydroxides and oxides enriched in Cr, and an inner Cr2O3 layer. Outermost NiO coexists with small amount of Cr2O3 layer, while in the inner oxide only Cr2O3 remains. The oxide layers at medium and high DH contents (3.1458– 8.9880 mg/kg) consisted of an outermost layer of Ni(OH)2 and Cr(OH)3 enriched in Cr, an intermediate layer of metallic Ni, hydroxides and oxides enriched in Cr, and an inner Cr2O3 layer. In addition, boron compounds containing B3+ ions were accumulated in the thick and porous NiO layer formed at low DH contents, whereas the accumulation of boron compounds did not occur in the thin and dense polyhedral oxide layer formed at medium and high DH contents.

Damping efficiency of two-layer polyurethane composites

2021 ◽  
Vol 43 (1) ◽  
pp. 12-18
Author(s):  
N.V. Babkina ◽  
◽  
O.I. Antonenko ◽  
L.F. Kosyanchuk ◽  
O.O. Brovko ◽  
...  
Keyword(s):  
Chemical Nature ◽  
Layer Structure ◽  
Linear Structure ◽  
Temperature Range ◽  
Layer Composite ◽  
The Difference ◽  
Relaxation Maximum ◽  
Polyurethane Composites ◽  
Two Temperature

In this work, based on the results of dynamic mechanical studies, the damping efficiency of two-layer polyurethane (PU) composites designed by gluing two films of synthesized PU with different glass transition temperatures (Tg) was estimated. The damping efficiency was estimated by the parameters of the mechanical losses (tanδ) peak. To vary Tg, three types of PU with different chemical nature and structure were synthesized. The effect of an increase in the difference between the Tg of the initial PU (ΔTg) on the damping efficiency of the two-layer PU composites formed from them is analyzed. The effective damping temperature range (ΔT) was estimated as the temperature range under conditions tanδ ≥ 0,3 and tanδ ≥ 0,6. It was shown that at ΔТg = 7 °С a two-layer PU composite has one relaxation maximum, and its temperature range of damping efficiency expands in comparison with ΔТ for individual PU. Under the conditions ΔТg = 23 °С and ΔТg = 30 °С, two-layer PU composites exhibit damping efficiency in two temperature regions at tanδ ≥ 0,3, which provides an additional temperature range of effective damping. The essential role of the PU structure of each of the layers in the formation of a two-layer composite by gluing has been determined. Easier penetration of residues of the adhesive organic solvent into the surface of the PU film with a linear structure leads to plasticization of the corresponding layer in the composite and reduces Tg. It is shown that a two-layer structure can be used to solve specific problems related to the adjustment or broadening the effective damping temperature range.

Scarbroite, Al5(OH)13CO3·5H2O, compared with gibbsite and hydrotalcite

1980 ◽  
Vol 43 (329) ◽  
pp. 615-618 ◽  
Author(s):  
G. W. Brindley
Keyword(s):  
Layer Structure ◽  
Water Molecules ◽  
Crystal Chemical ◽  
Thermal Transformations ◽  
Temperature Range ◽  
Third Phase ◽  
Initial Spacing

SummaryThe composition of scarbroite, written in the form Al5(OH)13CO3·5H2O, suggests close crystal-chemical relations to gibbsite and to hydrotalcite and kindred minerals. Parametral relations a(S) ≃ 2b(G) and 3b(S) ≃ 5a(G), S = scarbroite, G = gibbsite, are obtained and are consistent with a hydroxy Al layer structure and interlayer carbonate anions and water molecules. Thermal transformations show two discrete hydrated phases with layer spacings near 8.5 and 7.65 Å and a third phase with initial spacing 6.65 Å which decreases progressively to 5.5 Å over the temperature range 100°–250 °C as decomposition proceeds. No clear break is observed between dehydroxylation and decarbonation.

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