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61.
Incorporation of phosphorus into silicon from a spin-on dopant layer (SOD) at 400 °C is described.
Annealing experiments were carried out with SOD films deposited on (100) silicon substrates by using the spin-on technique.
Conventional heating on a hotplate in normal atmosphere and a temperature range up to 400 °C was used to study the dopant incorporation. After removing the SOD-films one part of the silicon substrates was annealed
at higher temperatures. Investigations were carried out by SIMS, SAM, XPS, HTEM, stripping Hall and Van der Pauw measurements
before and after the high temperature annealing.
Chemical phosphorus concentration profiles obtained from low temperature annealed samples showed diffusion depths of 60–80 nm
(extrapolated to a substrate doping level of 1016 cm-3) and surface concentrations of 1019–1020 cm-3. Electron concentration profiles exhibiting maximum values around 2⋅1019 cm-3 could be measured on high temperature annealed samples only.
Received: 28 March 1996/Accepted: 19 August 1996 相似文献
62.
Xiaohui Liu Qiuju Wu Qingxin Zhang Zhishen Mo 《Journal of Polymer Science.Polymer Physics》2003,41(1):63-67
The crystalline‐phase transition in polyamide‐66/montmorillonite nanocomposites before melting was investigated by in situ X‐ray diffraction and is reported for the first time in this work. The phase‐transition temperature in the nanocomposites was 170 °C, 20 °C lower than that in polyamide‐66. The lower phase‐transition temperature of the nanocomposites could be attributed to the γ‐phase‐favorable environment caused by silicate layers. Meanwhile, the addition of silicate layers changed the crystal structure of the polyamide‐66 matrix and influenced the phase‐transition behavior. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 63–67, 2003 相似文献
63.
Mimi Y. Keating 《Journal of Thermal Analysis and Calorimetry》2005,82(3):559-564
Summary Thermal analysis of the 10 μm surface of materials using TA Instruments' μ-TA thermal probe and pulsed force mode AFM has
shown promising results. This addresses the need of additional surface characterization based on principle of Thermal Analysis,
which is complementary to other surface characterization techniques, i.e., Surface-IR, TOF-SIMS, etc. The method calls for
identification of surface landscape by imaging first, followed by fast heating the spots of interest. The micro thermal probe
is viewed to heat a small material with a tiny heater rather than to heat small material with a large heater in conventional
thermal analysis. In this paper, we demonstrate the applicability in the adhesion temperature of the topical coatings of Tyvek?
HDPE sheets, fusion of the heat-processed polyethylene fibers in a bundle, the surface crystallinity of PET pellets, and two
examples of phase images of toughened Nylon 66. Comparisons were made where it is possible with standard thermal analysis
techniques as well as with the microscopic techniques of AFM, TEM and optical. 相似文献
64.
Hélène Airault 《Bulletin des Sciences Mathématiques》2002,126(5):343-367
With a method close to that of Kirillov [4], we define sequences of vector fields on the set of univalent functions and we construct systems of partial differential equations which have the sequence of the Faber polynomials (Fn) as a solution. Through the Faber polynomials and Grunsky coefficients, we obtain the generating functions for some of the sequences of vector fields. 相似文献
65.
Aequationes mathematicae - 相似文献
66.
N. Kjurkchiev 《BIT Numerical Mathematics》1992,32(3):525-528
In this paper we obtain upper and lower bounds for the unique positive roots of certain sequences of polynomials. The results are then applied to the determination of theR-order of iterative numerical processes. 相似文献
67.
S. Gogolewski M. Gasiorek K. Czerniawska A. J. Pennings 《Colloid and polymer science》1982,260(9):859-863
Effect of annealing on thermal behaviour and crystalline structure of meltcrystallized nylon 6 has been investigated.The annealing process is found to be characterized by an incubation period followed by a more or less doubling of the SAXS long spacing and of the crystallinity.The extrapolated heat of melting of the crystalline phase of nylon 6 in the-modification is 188 Jg–1 and its extrapolated equilibrium melting temperature is 260 °C.Presented in part at 28th IUPAC Symposium on Macromolecules, Strasbourg, July, 1981. 相似文献
68.
In [L. Lebtahi, Lie algebra on the transverse bundle of a decreasing family of foliations, J. Geom. Phys. 60 (2010), 122–133], we defined the transverse bundle Vk to a decreasing family of k foliations Fi on a manifold M. We have shown that there exists a (1,1) tensor J of Vk such that Jk≠0, Jk+1=0 and we defined by LJ(Vk) the Lie Algebra of vector fields X on Vk such that, for each vector field Y on Vk, [X,JY]=J[X,Y]. 相似文献
69.
Enhancement of the surface properties of a material by means of laser radiation has been amply demonstrated previously. In this work a comparative study for the surface modification of nylon 6,6 has been conducted in order to vary the wettability characteristics using CO2 and excimer lasers. This was done by producing 50 μm spaced (with depths between 1 and 10 μm) trench-like patterns using various laser parameters such as varying the laser power for the CO2 laser and number of pulses for the excimer laser. Topographical changes were analysed using optical microscopy and white light interferometry which indicated that both laser systems can be implemented for modifying the topography of nylon 6,6. Variations in the surface chemistry were evaluated using energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy analysis which showed that the O2 increased by up to 1.5 at% and decreased by up to 1.6 at% for the CO2 and F2 laser patterned samples, respectively. Modification of the wettability characteristics was quantified by measuring the advancing contact angle, which was found to increase in all instances for both laser systems. Emery paper roughened samples were also analysed in the same manner to determine that the topographical pattern played a major role in the wettability characteristics of nylon 6,6. From this, it is proposed that the increase in contact angle for the laser processed samples is due to a mixed intermediate state wetting regime owed to the periodic surface roughness brought about by the laser-induced trench-like topographical patterns. 相似文献
70.