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1.
X. Wang Y. C. Liu C. Wei L. M. Yu Z. M. Gao Z. Z. Dong 《Applied Physics A: Materials Science & Processing》2009,96(4):969-973
The effects of Bi addition, of less than 3 wt.%, and applied cooling rate on the solidified microstructure of the eutectic
Sn–3.7Ag–0.9Zn (weight percent, hereafter) solder were investigated. As observed by microstructural analysis, the increase
of Bi content favors the separation of the β-Sn and AgZn intermetallic compounds (IMCs) in the eutectic Sn–Ag–Zn solder. And there are some Bi precipitates formed along
with the primary β-Sn dendrites as the concentration of Bi exceeds 2%. As the applied cooling rate increases, the microstructure of the Sn–3.7Ag–0.9Zn–Bi
solder is refined, and the segregation of Bi is restrained. By increasing the amount of Bi, the microhardness of the solder
increases. 相似文献
2.
Effects of the single addition of nitrogen (N) and boron (B) and the combined addition of N and B on continuous cooling transformation (CCT) diagrams and properties of the three Mo–V–Ti micro-alloyed steels were investigated by means of a combined method of dilatometry and metallography. Microstructures observed in continuous cooled specimens were composed of pearlite (P), quasi-polygonal ferrite (QPF), granular bainite (GB), acicular ferrite (AF), lath-like bainite (LB) and martensite (M) depending on the cooling rates and transformation temperatures. Single addition of 12?ppm B effectively reduced the formation of QPF and broadened the cooling rate region for LB and M. Added N makes the action of B invalid and the QPF region was prominently broadened, and even though the cooling rate is higher than 50°C?s?1, it cannot obtain full bainite. 相似文献
3.
K. Schouteden P. Lievens C. Van Haesendonck 《Applied Physics A: Materials Science & Processing》2009,96(2):409-413
The structural stability of rapidly solidified (about 104 K/s) Sn–3.7Ag–0.9Zn eutectic solder was explored by high-temperature annealing. For the as-cast solders, the applied fast
cooling rate had a significant influence on the microstructure of the solders. The faster the applied cooling rates, the smaller
the β-Sn dendrites. After annealing at 473 K for 20 and 50 h, β-Sn dendrites congregated together into bulk ones for minimizing the interfacial energy, and Ag3Sn intermetallic compounds (IMCs) as well as ternary Ag–Zn–Sn IMCs segregated on the grain boundary of the β-Sn dendrites. It seems that the coarsening of the β-Sn dendrites in the rapidly solidified specimen brought a significant softening during annealing of the explored Sn–Ag–Zn
alloy. Finally, the β-Sn dendrites vanished gradually with increase of the annealing period, which leads to a kind of softening. 相似文献
4.
The characteristics of a BaO–Al2O3–B2O3–SiO2–La2O3 glass ceramic prepared by spray pyrolysis were studied. Glass powders with spherical shape and amorphous phase were prepared
by complete melting at a preparation temperature of 1 500°C. The mean size and geometric standard deviation of the powders
prepared at the temperature of 1 500°C were 0.6 μm and 1.3. The glass powders had similar composition to that of the spray
solution. The glass transition temperature (T
g) of the glass powders was 600.3°C. Two crystallization exothermic peaks were observed at 769.3 and 837.8°C. Densification
of the specimen started at a sintering temperature of 600°C, in which Ba4La6O(SiO4)6 as main crystal structure was observed. Complete densification of the specimen occurred at a sintering temperature of 800°C.
The specimens sintered at temperatures above 800°C had main crystal structure of BaAl2Si2O8. 相似文献
5.
Woei-Shyan Lee Tao-Hsing Chen Chi-Feng Lin Jyun-Ming Chen 《Applied Physics A: Materials Science & Processing》2010,100(4):1089-1096
Thin Ni/Si films are prepared by depositing a Ni layer with a thickness of 100 nm on a Si (100) substrate. The as-deposited
thin-film specimens are indented to a maximum depth of 500 nm using a nanoindentation technique and are then annealed at temperatures
of 200°C, 300°C, 500°C and 800°C for 2 min. The microstructural changes and phases induced in the various specimens are observed
using transmission electron microscopy (TEM) and micro-Raman scattering spectroscopy (RSS). Based on the load-displacement
data obtained in the nanoindentation tests, the hardness and Young’s modulus of the as-deposited specimens are found to be
13 GPa and 177 GPa, respectively. The microstructural observations reveal that the nanoindentation process prompts the transformation
of the indentation-affected zone of the silicon substrate from a diamond cubic structure to a mixed structure comprising amorphous
phase and metastable Si III and Si XII phases. Following annealing at temperatures of 200∼500°C, the indented zone contains
either a mixture of amorphous phase and Si III and Si XII phases, or Si III and Si XII phases only, depending on the annealing
temperature. In addition, the annealing process prompts the formation of nickel silicide phases at the Ni/Si interface or
within the indentation zone. The composition of these phases depends on the annealing temperature. Specifically, Ni2Si is formed at a temperature of 200°C, NiSi is formed at a temperature of 300°C and 500°C, and NiSi2 is formed at 800°C. 相似文献
6.
Di Liang Alexander W. Fang Hui-Wen Chen Matthew N. Sysak Brian R. Koch Erica Lively Omri Raday Ying-Hao Kuo Richard Jones John E. Bowers 《Applied Physics A: Materials Science & Processing》2009,95(4):1045-1057
We discuss the recently developed hybrid silicon evanescent platform (HSEP), and its application as a promising candidate
for optical interconnects in silicon. A number of key discrete components and a wafer-scale integration process are reviewed.
The motivation behind this work is to realize silicon-based photonic integrated circuits possessing unique advantages of III–V
materials and silicon-on-insulator waveguides simultaneously through a complementary metal-oxide semiconductor fabrication
process. Electrically pumped hybrid silicon distributed feedback and distributed Bragg reflector lasers with integrated hybrid
silicon photodetectors are demonstrated coupled to SOI waveguides, serving as the reliable on-chip single-frequency light
sources. For the external signal processing, Mach–Zehnder interferometer modulators are demonstrated, showing a resistance-capacitance-limited,
3 dB electrical bandwidth up to 8 GHz and a modulation efficiency of 1.5 V mm. The successful implementation of quantum well
intermixing technique opens up the possibility to realize multiple III–V bandgaps in this platform. Sampled grating DBR devices
integrated with electroabsorption modulators (EAM) are fabricated, where the bandgaps in gain, mirror, and EAM regions are
1520, 1440 and 1480 nm, respectively. The high-temperature operation characteristics of the HSEP are studied experimentally
and theoretically. An overall characteristic temperature (T
0) of 51°C, an above threshold characteristic temperature (T
1) of 100°C, and a thermal impedance (Z
T
) of 41.8°C/W, which agrees with the theoretical prediction of 43.5°C/W, are extracted from the Fabry–Perot devices. Scaling
this platform to larger dimensions is demonstrated up to 150 mm wafer diameter. A vertical outgassing channel design is developed
to accomplish high-quality III–V epitaxial transfer to silicon in a timely and dimension-independent fashion. 相似文献
7.
S.D. Cheng X.Q. Han C.H. Kam Y. Zhou Y.L. Lam J.T. Oh X.W. Xu T.C. Chong 《Applied Physics A: Materials Science & Processing》2001,73(4):511-514
We have successfully prepared highly c-axis-textured LiNbO3 films on hydrogen-terminated Si (111) substrate using sol-gel spin-coating and rapid thermal annealing. These highly c-axis-textured
films were obtained with a preheating at 300 °C for 15 min followed by a rapid thermal annealing at 500–700 °C for 120 s.
The c-axis orientation of the LiNbO3 film is due to a weak effect caused by the 3-fold symmetry match between the film and the Si (111) substrate. The c-axis
orientation of LiNbO3 films is very useful in integrated optics devices and metal–ferroelectric–semiconductor nonvolatile memory applications.
Received: 15 September / Accepted: 4 December / Published online: 3 April 2001 相似文献
8.
Huanfu Zhou Hong Wang Minghui Zhang Xi Yao 《Applied Physics A: Materials Science & Processing》2009,95(2):513-516
A new Li2O–Nb2O5–TiO2 (LNT) ceramic with the Li2O:Nb2O5:TiO2 mole ratio of 5.5:1:7 was prepared by solid state reaction route. The phase and structure of the ceramic were characterized
by X-ray diffraction and scanning electron microscopy (SEM). The microwave dielectric properties of the ceramics were studied
using a network analyzer. The microwave dielectric ceramic has low sintering temperature (∼1075°C) and good microwave dielectric
properties of ε
r=42, Q×f=16900 GHz (5.75 GHz), and τ
f
=63.7 ppm/°C. The addition of B2O3 can effectively lower the sintering temperature from 1075 to 875°C and does not induce degradation of the microwave dielectric
properties. Obviously, the LNT ceramics can be applied to microwave low temperature-cofired ceramics (LTCC) devices. 相似文献
9.
Doo-Hyeb Youn Seong-Hyun Kim Yong-Suk Yang Sang-Chul Lim Seong-Jin Kim Su-Han Ahn Hyo-Sun Sim Seung-Myoung Ryu Dong-Wook Shin Ji-Beom Yoo 《Applied Physics A: Materials Science & Processing》2009,96(4):933-938
This paper introduces for the first time near-field electrohydrodynamic jet printing with tilted-outlet nozzle to obtain the fine and highly conductive patterns of silver (Ag) ink. Line widths produced by near-field electrohydrodynamic
jet printing are less than 6 μm, which is approximately twenty times smaller than that of inkjet printing. Under optimized
Ag ink annealing ranges 3–9 min for 30 wt% at 150°C, we observed Ag line pattern resistivities as low as 7×10−6 Ω⋅cm. Ag ink conduction mechanisms were brought to light from microstructure analysis and post-thermal-annealing examination
of electrical characteristics. 相似文献
10.
R.A. Gunasekaran J.D. Pedarnig M. Dinescu 《Applied Physics A: Materials Science & Processing》1999,69(6):621-624
A parametric study of the growth of La0.5Sr0.5CoO3 (LSCO) thin films on (100) MgO substrates by pulsed-laser deposition (PLD) is reported. Films are grown under a wide range
of substrate temperature (450–800 °C), oxygen pressure (0.1–0.9 mbar), and incident laser fluence (0.8–2.6 J/cm2). The optimum ranges of temperature, oxygen pressure, and laser fluence to produce c-axis oriented films with smooth surface morphology and high metallic conductivity are identified. Films deposited at low
temperature (500 °C) and post-annealed in situ at higher temperatures (600–800 °C) are also investigated with respect to their
structure, surface morphology, and electrical conductivity.
Received: 20 November 1998 / Accepted: 6 July 1999 / Published online: 21 October 1999 相似文献
11.
Hao Wang Y. Wang J. Feng C. Ye B. Y. Wang H. B. Wang Q. Li Y. Jiang A. P. Huang Z. S. Xiao 《Applied Physics A: Materials Science & Processing》2008,93(3):681-684
High-k gate dielectric hafnium dioxide films were grown on Si (100) substrate by pulsed laser deposition at room temperature. The
as-deposited films were amorphous and that were monoclinic and orthorhombic after annealed at 500°C in air and N2 atmosphere, respectively. After annealed, the accumulation capacitance values increase rapidly and the flat-band voltage
shifts from −1.34 V to 0.449 V due to the generation of negative charges via post-annealing. The dielectric constant is in
the range of 8–40 depending on the microstructure. The I–V curve indicates that the films possess of a promising low leakage
current density of 4.2×10−8 A/cm2 at the applied voltage of −1.5 V. 相似文献
12.
Hao Chen Yongchang Liu Zesheng Yan Yanli Li Lifang Zhang 《Applied Physics A: Materials Science & Processing》2010,98(1):211-217
The three cooling rates of 10, 100, 200 K/min dilatometry experiments are used to investigate the kinetics of the isochronal
austenite (γ) to ferrite (α) transformation of Fe–0.0036wt.%C alloy. “Normal transformation” and “abnormal transformation” have both been observed for
transformations at different cooling rates. In accordance with the thermodynamic characteristics of the γ→α transformation investigated here and previous kinetic considerations, a JMAK-like approach for the kinetics of isochronal
phase transformations was developed that incorporates three overlapping processes: site saturation nucleation, alternate growth
modes (from interface-controlled to diffusion-controlled to interface-controlled growth), as well as impingement for random
distribution nuclei. The JMAK-like approach has been employed to fit the experimental results, and the fitting results show
that for the γ→α transformation of the Fe–C alloy at all applied cooling rates, the growth mode evolves in the corresponding order: from interface-controlled
to diffusion-controlled growth; from interface-controlled to diffusion-controlled to interface-controlled growth; and interface-controlled
growth. 相似文献
13.
Chivalrat Masingboon Prasit Thongbai Santi Maensiri Teerapon Yamwong 《Applied Physics A: Materials Science & Processing》2009,96(3):595-602
Nanocrystalline CaCu3Ti4O12 powders were synthesized by a simple PVA sol–gel route and calcined at 700 and 800°C in air for 8 h. The diameter of the
powders ranges from 40–100 nm. The calcined CaCu3Ti4O12 powders were characterized by TG-DTA, XRD, FTIR, SEM, and TEM. Sintering of the powders was conducted in air at 1100°C for
16 h. The XRD results indicated that all sintered samples had a typical perovskite CaCu3Ti4O12 structure although the sintered samples contained some amount of CaTiO3. SEM of the sintered CaCu3Ti4O12 ceramics showed the average grain sizes of 13–15 μm. The samples exhibit a giant dielectric constant, ε′∼105 at 150 to 200°C with weak temperature dependence below 1 kHz in the sample sintered using the powders calcined at 700°C.
The Maxwell–Wagner polarization mechanism is used to explain the high permittivity in these ceramics. It is also found that
all sintered samples have the same activation energy of grains, which is ∼0.122 eV. 相似文献
14.
W. Maziarz J. Dutkiewicz R. Santamarta E. Cesari 《The European physical journal. Special topics》2008,158(1):137-142
The microstructure of Co35 + x-Ni40 - x-Al25 (x = 0, 2.5, 5.0) ferromagnetic shape memory alloys annealed at 1200 °C and water quenched has been investigated by optical
(OM) and analytical transmission electron microscopy (TEM). The microstructure consists of elongated grains of martensite
and γ phase. Annealing twins were found frequently in the γ phase. The volume fraction of γ phase has been determined to be
about 40%. TEM observations show twinned L10 martensite with {111}-type twinning plane and tetragonality c/a = 0.85 in all investigated alloys. Determination of the composition
of β phase, allows to calculate Al/Co and e/a ratio in the range 7.68–8.40 in correlation with its Ms temperatures between
66 and 167 °C, respectively. An increase in the Al/Co ratio together with a decrease of Ni content in β phase causes a decrease
of the e/a ratio, which promotes a decrease of martensitic transformation temperatures. 相似文献
15.
Kuo-Sheng Kao Shang-Hao Chang Po-Tsung Hsieh Chih-Ming Wang Da-Long Cheng 《Applied Physics A: Materials Science & Processing》2009,96(2):529-533
Three-layered ZnO/Ag–Ti/ZnO structures were prepared using both the sol-gel technique and DC magnetron sputtering. This study
focuses on the electrical and optical properties of the ZnO/Ag–Ti/ZnO multilayers with various thicknesses of the Ag–Ti layer.
The ZnO thin film prepared by the sol–gel method was dried at 300°C for 3 minutes, and a fixed thickness of 20 nm was obtained.
The thickness of the Ag–Ti thin film was controlled by varying the sputtering time. The Ag–Ti layer substantially reduced
the electrical resistivity of the sol–gel-sprayed ZnO thin films. The sheet resistance of the Ag–Ti layer decreased dramatically
and then became steady beyond a sputtering time of 60 s. The sputtering time of Ag–Ti thin film deposition was determined
to be 60 s, taking into account the optical transmittance. Consequently, the transmittance of the ZnO/Ag–Ti/ZnO multilayer
films was 71% at 550 nm and 60% at 350 nm. The sheet resistance was 4.2 Ω/sq. 相似文献
16.
M. Tamura Y. Hiroyama A. Nishida M. Horiuchi 《Applied Physics A: Materials Science & Processing》1998,66(4):373-384
14 /cm2 dose of As ions followed by both isochronal and isothermal annealing. The elementary defects generated first during solid-phase
epitaxial recovery of implantation-induced amorphous layers at temperatures of 550 °C and/or 600 °C are {311} defects 2–3 nm
long. They are considered to be transformed into {111} and {100} defects after annealing at temperatures higher than 750 °C.
These secondary defects show the opposite annealing behavior to the dissolution and growth by the difference of their depth
positions at 800 °C. This phenomenon is explained by the diffusion of self-interstitials contained in defects. With regard
to the formation and dissolution of defects, there is no significant difference between the effects of rapid thermal annealing
(950 °C for 10 s) and furnace annealing (800 °C for 10 min).
Received: 14 November 1997/Accepted: 16 November 1997 相似文献
17.
S. N. Danil’chenko A. N. Kulik P. A. Pavlenko T. G. Kalinichenko A. N. Bugai I. I. Chemeris L. F. Sukhodub 《Journal of Applied Spectroscopy》2006,73(3):437-443
We have attempted to use heat treatment followed by ultrasonic treatment to separate the apatite from the non-apatite components
of bone mineral in samples from different animals. The Mg content and the Ca/P ratio in the temperature range 560°C–720°C
in the samples before and after ultrasonic treatment were determined by electron-probe x-ray microanalysis. Furthermore, we
used atomic absorption spectrometry to measure the Mg content in powdered bone samples only after annealing and in distilled
water, which was the “sonication” medium. We obtained evidence for thermally activated transition of Mg from a structurally
bound state to a labile state at 680°C–720°C. At the same temperature, the Ca-deficient apatite is transformed to stoichiometric
apatite. The data presented are evidence that crystals of Ca-deficient bioapatite are surrounded by Ca-enriched surface layers.
As a result of thermal transformations at 680°C-720°C, all the Mg in the biomineral is found in the non-apatite environment
surrounding the crystals and is removed by ultrasonic treatment, while the surface-localized Ca penetrates into the apatite
lattice, restoring its stoichiometry.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 3, pp. 385–391, May–June, 2006. 相似文献
18.
Diffraction electron microscopy was used in a study of the decay kinetics of the α-iron solid solution and the growth kinetics
of cementite particles in steel 38KhN3MFA after tempering at 200–550°C. Growth equations are written for cementite particles
formed in lamellar high-temperature martensite crystals.
Tomsk Structural Engineering Institute, Tomsk. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp.
39–44, February, 1993. 相似文献
19.
L. Pintilie I. Pintilie D. Petre T. Botila M. Alexe 《Applied Physics A: Materials Science & Processing》1999,69(1):105-109
Thermally stimulated current (TSC) measurements performed in the 100 K–400 K temperature range on Bi4Ti3O12 (BiT) thin films annealed at 550 °C and 700 °C had revealed two trapping levels having activation energies of 0.55 eV and
0.6 eV. The total trap concentration was estimated at 1015 cm−3 for the samples annealed at 550 °C and 3×1015 cm−3 for a 700 °C annealing and the trap capture cross-section was estimated about 10−18 cm2. From the temperature dependence of the dark current in the temperature range 20 °C–120 °C the conduction mechanism activation
energy was found to be about 0.956–0.978 eV. The electrical conductivity depends not only on the sample annealing temperature
but also whether the measurement is performed in vacuum or air. The results on the dark conductivity are discussed considering
the influence of oxygen atoms and oxygen vacancies.
Received: 28 January 1998 / Accepted: 8 January 1999 / Published online: 5 May 1999 相似文献
20.
Hopp B. Smausz T. Kresz N. Nagy P.M. Juhász A. Ignácz F. Márton Z. 《Applied Physics A: Materials Science & Processing》2003,76(5):731-735
Allergic-type diseases are current nowadays, and they are frequently caused by certain metals. We demonstrated that the metal
objects can be covered by Teflon protective thin layers using a pulsed laser deposition procedure. An ArF excimer laser beam
was focused onto the surface of pressed PTFE powder pellets; the applied fluences were 7.5–7.7 J/cm2. Teflon films were deposited on fourteen-carat gold, silver and titanium plates. The number of ablating pulses was 10000.
Post-annealing of the films was carried out in atmospheric air at oven temperatures between 320 and 500 °C. The thickness
of the thin layers was around 5 μm. The prepared films were granular without heat treatment or after annealing at a temperature
below 340 °C. At 360 °C a crystalline, contiguous, smooth, very compact and pinhole-free thin layer was produced; a melted
and re-solidified morphology was observed above 420 °C. The adhesion strength between the Teflon films and the metal substrates
was determined. This could exceed 1–4 MPa depending on the treatment temperature. It was proved that the prepared Teflon layers
can be suitable for prevention of contact between the human body and allergen metals and so for avoidance of metal allergy.
Received: 12 June 2002 / Accepted: 13 June 2002 / Published online: 4 November 2002
RID="*"
ID="*"Corresponding author. E-mail: bhopp@physx.u-szeged.hu 相似文献