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51.
This paper describes the design, fabrication, and characteristics of micro heaters mad on AlN (0.1 μm)/3C-SiC (1 μm) suspended membranes using surface micromachining technology. 3C-SiC and AlN thin films, which have a large energy band gap and very low lattice mismatch, were used for high-temperature environments. A Pt thin film was used as micro heaters and temperature sensor materials. The resistance of the temperature detector (RTD) and the power consumption of the micro heater were measured and calculated. The heater is designed for an operating temperature up to about 800 °C and can be operated at about 500 °C with a power of 312 mW. The thermal coefficient of the resistance (TCR) of fabricated Pt RTD’s is 3174.64 ppm/°C. The thermal distribution measured by IR thermovision is uniform across the membrane surface. 相似文献
52.
C. Demeurisse P. Verheyen K. Opsomer C. Vrancken P. Absil A. Lauwers 《Microelectronic Engineering》2007,84(11):2547-2551
NiPt (10% Pt) and Pt were investigated as alternatives to Ni for contact formation to SiGe (20%) source/drain. The germanosilicide phase formation and morphology were studied by means of sheet resistance measurements, X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) inspection. From isothermal anneals it is found that NiPt- and Pt-germanosilicide have better thermal stability compared to Ni-germanosilicide. Improved thermal stability is observed for Ni-, NiPt- and Pt-germanosilicide on B doped SiGe as compared to undoped SiGe. The degradation mechanism of NiPt- and Pt-germanosilicide films on SiGe is morphological degradation while the film is still in the mono-(germanosilicide) phase. 相似文献
53.
In this work, gas response properties of Pd modified TiO2 sensing films are discussed when exposed to H2 and O2. TiO2 films are surface modified in PdCl2-containing solution by the dipping method and treated for different treatment times to get different surface states. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and Kröger–Vink defect theory are used to characterize the sensing films. The gas response properties indicate that the sensor response time which related to the rate of change of sensor resistance is affected by the activation energy (E). In particular, the sensor treated at 900 °C for 2 h exhibits a response time of about 20–240 ms when exposed to H2 and 40–130 ms when exposed to O2 at 500–800 °C. 相似文献
54.
55.
Very thin films, less than 100 nm-thick, are used in a variety of applications, including as catalysts and for thin film reactions
to form patterned silicides in electronic devices. Because of their high surface to volume ratio, these very thin films are
subject to cap-illary instability and can agglomerate well below their melting temperatures. In order to develop a general
understanding of agglomeration in very thin films, we have studied initially continuous and patterned films of gold on fused
silica substrates. Two in situ techniques were used to monitor agglomeration: 1) heating and video recording in a transmission
electron microscope, and 2) measurement of the intensity of laser light transmitted through a sample heated in a furnace.
Electron microscopy allowed inves-tigation of the role of the microstructure of the Au film and analysis of light transmis-sion
during heating allowed determination of temperature-dependent and film-thick-ness-dependent agglomeration rates. These results
will be described along with models for the agglomeration process. 相似文献
56.
M. A. Dornath-Mohr M. W. Cole H. S. Lee D. C. Fox D. W. Eckart L. Yerke C. S. Wrenn R. T. Lareau W. H. Chang K. A. Jones F. Cosandey 《Journal of Electronic Materials》1990,19(11):1247-1255
Low temperature, non-alloyed Au-Ge contact formation ton-GaAs is a multi-step pro-cess. During the first 5 min of annealing at 320° C the Au and Ge segregate into regions a few microns
in size and extend over the entire thickness of the metal layer and sig-nificant in-diffusion of the Au and Ge and out-diffusion
of the Ga and As occurs. This intermixing reduces the barrier height from 0.75 to 0.40 eV. The contact does not show ohmic
behavior until it has been annealed for 3 hr. During this time Ge continues to in-diffuse but at a slower rate than it did
initially. The rate of Ge in-diffusion is en-hanced by the presence of Au since samples containing less Au require longer
anneals to show ohmic behavior and have higher specific contact resistances. The presence of excess As, which is prevented
from evaporating by a Si3N4 cap has the opposite effect since capped layers have higher specific contact resistances. Au-Ge phases appear after approximately
3 hr of annealing, therefore, Au-Ge phases cannot be responsible for the reduction in barrier height. The interface morphology
is smooth, differing from that of pure Au and alloyed contacts that often contain spiking of the metals into the semi-conductor.
The orientation relationship for the Au grains differs from that of pure Au.
Work performedat U.S. Army ETDL, Fort Monmouth, NJ 07703.
Work performed at U.S.Army ETDL, Fort Monmouth, NJ 07703. 相似文献
57.
We studied silver barrier ohmic (Ni/AuGe/Ag/Au) contacts to the GaAs based HEMT structures and observed strong dependence
of the cleaning procedures on the ohmic con-tact resistance (Rc), its stability and reliability. The chemical profiles of the metal con-tacts before and after alloying were measured by
SIMS. Samples cleaned with the com-bined plasma O2 and NH4OH process exhibited excellent results:R
c ∼ 0.1–0.12 ohm-mm when alloyed in the temperature range of 440–540° C and remained stable when subjected to a 200° C and
600mA/mm stress condition for 1000 hr. 相似文献
58.
Seong-Chan Bae 《Microelectronics Journal》2006,37(2):167-173
The field emission characteristics of an oxidized porous polysilicon were investigated with different annealing temperatures. Pt/Ti, Ir, and Au/NiCr were used as surface emitter electrodes, and Pt/Ti emitter showed highly efficient and stable electron emission characteristic compared with the conventional Au/NiCr electrode. Thin Ti layer played an important role in promotion of adhesion of Pt to SiO2 surface and uniform distribution of electric field on the OPPS surface. Additionally, the Ti layer efficiently blocked the diffusion of emitter metal, which resulted in more reliable emission characteristics. Pt/Ti emitter annealed at 350 °C/1 h showed the highest efficiency of 3.36% at Vps=16 V, which resulted from the improvement of interfacial contact characteristics of thin emitter metal to an oxidized porous polysilicon. Annealing above 400 °C showed that Pt/Ti and Ir emitter electrode were thermally more stable than Au/NiCr emitter. 相似文献
59.
During the reflowing of Sn-9Zn solder ball grid array (BGA) packages with Au/Ni/Cu and Ag/Cu pads, the surface-finished Au
and Ag film dissolved rapidly and reacted with the Sn-9Zn solder to form a γ3-AuZn4/γ-Au7Zn18 intermetallic double layer and ε-AgZn6 intermetallic scallops, respectively. The growth of γ3-AuZn4 is prompted by further aging at 100°C through the reaction of γ-Au7Zn18 with the Zn atoms dissolved from the Zn-rich precipitates embedded in the β-Sn matrix of Sn-9Zn solder BGA with Au/Ni/Cu
pads. No intermetallic compounds can be observed at the solder/pad interface of the Sn-9Zn BGA specimens aged at 100°C. However,
after aging at 150°C, a Ni4Zn21 intermetallic layer is formed at the interface between Sn-9Zn solder and Ni/Cu pads. Aging the immersion Ag packages at 100°C
and 150°C caused a γ-Cu5Zn8 intermetallic layer to appear between ε-AgZn6 intermetallics and the Cu pad. The scallop-shaped ε-AgZn6 intermetallics were found to detach from the γ-Cu5Zn8 layer and float into the solder ball. Accompanied with the intermetallic reactions during the aging process of reflowed Sn-9Zn
solder BGA packages with Au/Ni/Cu and Ag/Cu pads, their ball shear strengths degrade from 8.6 N and 4.8 N to about 7.2 N and
2.9 N, respectively. 相似文献
60.
We report the Schottky performance and thermal reliability of a wide bandgap InGaP layer in contact with a Cu/Au metallic
system. An effective Schottky barrier height of 0.97 eV and an ideality factor of 1.21 can be achieved. The thermal reliability
of the resultant Schottky barrier diodes was analyzed using Auger electron spectroscopy and atomic force microscopy. The thermal
reliability could be main tained up to 450°C. The failure mechanism was attributable to the decomposition of the InGaP layer
and the interdiffusion of the chemical elements at higher temperature. Insensitive photoresponsivity with the in cident optical
power was found for the resultant Au/Cu-metal-semiconductor-metalphotodetectors (MSM-PDs). According to the measured temporal
response of the Au/Cu-MSM-PDs, the operation frequency could be above 10 GHz. 相似文献