Use of water vapor for suppressing the growth of unstable low-κ interlayer in HfTiO gate-dielectric Ge metal-oxide-semiconductor capacitors with sub-nanometer capacitance equivalent thickness

Annealing of high-permittivity HfTiO gate dielectric on Ge substrate in different gases (N₂, NH₃, NO and N₂O) with or without water vapor is investigated. Analysis by transmission electron microscopy indicates that the four wet anneals can greatly suppress the growth of a GeO_x interlayer at the dielectric/Ge interface, and thus decrease interface states, oxide charges and gate leakage current. Moreover, compared with the wet N₂ anneal, the wet NH₃, NO and N₂O anneals decrease the equivalent permittivity of the gate dielectric due to the growth of a GeO_xN_y interlayer. Among the eight anneals, the wet N₂ anneal produces the best dielectric performance with an equivalent relative permittivity of 35, capacitance equivalent thickness of 0.81 nm, interface-state density of 6.4 × 10¹¹ eV^− 1 cm^− 2 and gate leakage current of 2.7 × 10^− 4 A/cm² at V_g = 1 V.     

Correlation between local structure variations and critical temperature of (Bi1.6Pb0.4Sr2Ca2Cu3O10+δ)1-x(TiO2)x superconductor

TiO₂ doping content affects the critical temperature (T_c) and the variations of local structure on Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O_10+δ. The (Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O_10+δ)_1-x(TiO₂)_x samples were fabricated with the solid-state reaction process, where x = 0, 0.002, 0.004, 0.006, 0.008, and 0.01. The T_c values of the samples were obtained by measuring resistivity versus temperature, indicating that T_c gradually decreased with increasing doping content (x). To explain the obtained degradation of T_c, carrier properties, role of interlayer coupling, and local structure were systematically investigated using Azlamozov–Larkin theory and its Lawrence–Doniach modification for strong anisotropic superconductors. The calculation of excess conductivity at the mean field region showed that the c-axis coherence length (ξ_c) and the effective inter-layering spacing (d) increased with increasing doping content. X-ray diffraction patterns also showed that the bond distances increased with increasing TiO₂ content. The copper valence (V) and carrier concentration (p) of the samples were determined by analyzing the Cu L_2,3-edge X-ray absorption near edge structure spectra. The values of V and p showed the same trend of decreasing with increasing x. A close correlation between the changes in local structure parameters and degradation of T_c of (Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O_10+δ)_1-x(TiO₂)_x was then probably concluded.     

Joining of SiC ceramics by combining NITE-SiC interlayer and its thickness control

Combined with the thickness control of interlayers (∼10 µm and ∼60 µm), SiC nano-powders with Al₂O₃-Y₂O₃-MgO-CaO additive (NITE-SiC) were used as the joining materials to achieve the low-temperature joining of SiC ceramics. Some residual pores were observed in the interlayer with a thickness of ∼60 µm after joining at 1650 ℃, and the shear strength of SiC joints measured was 39.3 ± 5.5 MPa. Observations showed the fracture of joints occurred at the interlayer. When the thickness of the interlayer decreased to ∼10 µm, no cracks or porosity were observed at the interface region after joining at 1650 ℃. The shear strength of SiC joints increased to 69.5 ± 8.9 MPa, and the fracture originated from the matrix. The results demonstrated using NITE-SiC with Al₂O₃-Y₂O₃-MgO-CaO additive as the joining layer and reducing the thickness of the interlayer could lower the joining temperature and significantly improve the mechanical strength of joints.     

八面河油田北二区细分层开发研究

针对八面河油田中高渗厚层油藏层内出力不均的问题,采用层内剩余油分布有差异和夹层在电性上能够有效划分为精细划分标准,以剩余油监测结果为依据,结合夹层分布情况,选取岩性、电性特征较为明显的井为标准井进行砂岩细分。根据剩余油监测曲线中的夹层显示,以基线与监测曲线重合程度为依据,制定夹层的封堵性标准,进行有效夹层描述。     

Critical parameters in hot filament chemical vapor deposition of diamond films on tool steel substrates with CrN interlayers

The accomplishment of adherent and continuous diamond coatings on tool steel substrates with CrN interlayers is determined by many key parameters such as appropriate surface finish, interlayer thickness, substrate temperature and system pressure. A detailed study is carried out to probe the effect of these parameters on diamond nucleation and growth. Substrates with different surface finishes are prepared by electrical discharge machining (EDM) and CrN interlayers of various thicknesses are deposited onto these substrates by arc plating. Samples with a CrN interlayer of 2.5 μm are found to provide a continuous diamond film at a low pressure value of about 5 mbar. Nonetheless, the process window for obtaining such diamond layers is small, which results in limited reproducibility.     

Exact static analysis of partially composite beams and beam-columns

The ordinary differential equations and general solutions for the deflection and internal actions and, especially, the pertaining consistent boundary conditions for partially composite Euler–Bernoulli beams and beam-columns are presented. Static loading conditions, including transverse and axial loading and first- and second-order analyses are considered. The theoretical procedure is applicable to general loading and boundary conditions for uniform composite beams and beam-columns with interlayer slip. Further, the exact closed form characteristic equations and their associated exact buckling length coefficients for composite columns with interlayer slip are derived for the four Euler boundary conditions. It is shown that these coefficients are the same as those for ordinary fully composite (solid) columns, except for the Euler clamped-pinned case. For the clamped-pinned case, the difference between the exact buckling length coefficient and the corresponding value for solid columns is less than 1.8% depending on the so-called composite action parameter and relative bending stiffness parameter. Correspondingly, the maximum deviation between the exact and approximate buckling load is at most 2.5%. These small differences can in most practical cases be neglected. Also, the maximum theoretical range for the relative bending stiffness for partially composite beams and beam-columns is derived. An effective bending stiffness, valuable in the determination of the critical buckling load for partially composite members, is derived. This effective bending stiffness is also suitable for analysing approximate deflections and internal actions or stresses in composite beams with flexible shear connection. The beam-column analysis is applied to a specific case. The difference in the approaches to the first- and second-order analysis is illustrated and the results clearly show the magnification in the actions and displacements due to the second-order effect. The magnification of the internal axial forces is different from magnifications obtained for the other internal actions, since only that portion of an internal axial force that is induced by bending is magnified by the second-order effect.     

Controlling charge balance using non-conjugated polymer interlayer in quantum dot light-emitting diodes

The balance of electron–hole charge carriers in quantum dot (QD) light-emitting diodes (QLEDs) is an important factor to achieve high efficiency. However, poor interfacial properties between QDs and their adjacent layers are likely to deteriorate the electron–hole charge balance, resulting in the poor performance of a QLED. In this paper, we report an enhanced efficiency in red-emitting inverted QLEDs by modifying the interface properties between QDs and ZnO electron transport layer (ETL) using a thin layer of non-conjugated polymer, poly(4-vinylpyridine) (PVPy). Based on the precise control of the electrical properties with PVPy, the maximum efficiency of the QLED is enhanced by 30% compared to the device without a PVPy layer. In particular, the efficiency at low current density region is significantly increased. We investigate the effect of the PVPy interlayer on the performance of QLEDs and find that this thin layer not only shifts the energy levels of the underlying ZnO ETL, but also effectively blocks the leakage current at the ETL/QD interface.     

Ti过渡层厚度对Ti—TiN薄膜结合强度的影响

薄膜脱落的主要原因之一是受薄膜与基体上的界面应力影响,TiN薄膜和钢基体由于其力学性能差异较大,在界面上有很大的应力集中,在钢基体上沉积Ti过渡层能减小其界面应力。研究Ti过渡层厚度对膜基体系结合强度的影响．并借助有限元方法对不同过渡层厚度的膜基体系的界面应力进行分析,研究表明,适当厚度的过渡层能提高Ti-TiN膜层的结合强度。     

彩钢板墙面的施工

彩钢板墙面安装是非常重要的环节 ,必须引起足够的重视 ,同样的材料不同的队伍施工会出现截然不同的结果。在此本文就单层及夹芯保温彩钢板墙面的施工和主要节点处的防水构造方法进行了详细地介绍     

水平井开发块状边底水油藏的影响因素分析——以宋家垛油田周43块为例

由于水平井能有效抑制底水锥进,与直井相比具有很大优势,在边底水油藏中应用非常广泛.针对水平井的开发特征,运用数值模拟法,结合生产动态及物理模型试验方法从静态因素和生产动态因素两方面分析,总结了影响水平井开发块状边底水油藏的各项因素,提出了“水平井临界渗透率级差”概念,分析了油藏开发中后期驱动方式的转变,以期对同类油藏的...