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971.
Calcium copper titanate, CaCu3Ti4O12 (CCTO), thin films have been fabricated by Metal Organic Chemical Vapor Deposition on silicon substrates buffered with two different low-k interlayers, namely SiO2 and Si3N4. Depositions have been carried out from a molten mixture consisting of the Ca(hfa)2 • tetraglyme, Ti(tmhd)2(O-iPr)2, and Cu(tmhd)2 [Hhfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione; tetraglyme = 2,5,8,11,14-pentaoxapentadecane; Htmhd = 2,2,6,6-tetramethyl-3,5-heptandione; O-iPr = iso-propoxide] precursors. The chemical stability of CCTO films on both the SiO2 and Si3N4 low-k layers has been investigated by transmission electron microscopy in the perspective of their implementation in capacitor devices. 相似文献
972.
V. Ariel V. Garber D. Rosenfeld G. Bahir V. Richter N. Mainzer A. Sher 《Journal of Electronic Materials》1995,24(9):1169-1174
In this study, CdTe epilayers were grown by metalorganic chemical vapor deposition on epitaxial HgCdTe with the purpose of
developing suitable passivation for HgCdTe photodiodes. Two types of CdTe layers were investigated. One was grown directly,in situ, immediately following the growth of HgCdTe. The second type of CdTe was grown indirectly, on top of previously grown epitaxial
HgCdTe samples. In this case, the surface of the HgCdTe was exposed to ambient atmosphere, and a surface cleaning procedure
was applied. The material and structural properties of the CdTe/HgCdTe interfaces were investigated using secondary ion mass
spectroscopy, Auger electron spectroscopy, Rutherford back scattering, and x-ray double crystal diffractometry techniques.
Electrical properties of the CdTe/HgCdTe heterostructure were determined by capacitance-voltage (C-V) characterization of
Schottky barrier devices and metal insulator semiconductor devices. Also, a preliminary current-voltage characterization of
n+ p photodiodes was performed. A theoretical model suitable for analysis of graded heterojunction devices was used for interpretation
of C-V measurements. 相似文献
973.
974.
Matthias Uhlig A. Bertz J. -W. Erben S. E. Schulz T. Gessner D. Zeidler C. Wenzel J. Bartha 《Microelectronic Engineering》2003,70(2-4):314-319
The integration of ultra low k materials in copper damascene architecture is one of the main issues in finding microelectronic-process-compatible dielectric materials. The aim of this paper is to show the integration conformity with common equipment and process steps using a PECVD (plasma enhanced chemical vapor deposition) CF polymer ultra low k material in a Cu single damascene architecture (Proceedings of the Advanced Metallization Conference, 2002). The intermetal dielectric low k material used in the described structures has 2.1≤k≤2.3 (k depends on deposition process parameters [Microelectron. Eng. 50 (2000) 7–14]) and the copper was deposited by a metal organic chemical vapor deposition process. After chemical mechanical polishing the structures were characterized by scanning electron microscopy and electrical measurements. 相似文献
975.
用MOCVD技术在偏(1100)GaAs衬底上生长了发光波长在1.3μm的线状空间规则排列InAs量子点.光致发光实验表明,相对于正(100)衬底,偏(100)GaAs衬底上生长的InAs量子点具有更好的材料质量,光谱有更大的强度和更窄的线宽.为了得到发光波长为1.3μm的量子点,对比研究了不同In含量的InGaAs应力缓冲层(SBL)和应力盖层(SCL)的应力缓冲作用.结果表明,增加SCL中In含量能有效延伸量子点发光波长到1. 3μm,但是随着SBL中In的增加,发光波长变化不明显,并且材料质量明显下降. 相似文献
976.
InGaN films were deposited on(0001) sapphire substrates with GaN buffer layers under different growth temperatures by metalorganic chemical vapor deposition.The In-composition of InGaN film was approximately controlled by changing the growth temperature.The connection between the growth temperature,In content,surface morphology and defect formation was obtained by X-ray diffraction,scanning electron microscopy(SEM) and atomic force microscopy(AFM).Meanwhile,by comparing the SEM and AFM surface morphology images,we proposed several models of three different defects and discussed the mechanism of formation.The prominent effect of higher growth temperature on the quality of the InGaN films and defect control were found by studying InGaN films at various growth temperatures. 相似文献
977.
Mild heating of the Zn(C5F6HO2)2·2H2O·CH3(OCH2CH2)2OCH3 precursor allowed MOCVD deposition of ZnO films, in a low-pressure horizontal hot-wall reactor, on ITO substrates. The ZnO films were subsequently implanted with Sb ions. XRD measurements provided evidence that they consist of hexagonal, (002) and (101) oriented, crystals. UV–vis spectra showed that the transmittance of these films in the visible region is about 90%. The Sb implanted ZnO film showed a current-voltage characteristic that resembles that of a rectifying diode. This study represents the first example of Sb-implantation in ZnO films obtained by MOCVD. 相似文献
978.
This paper presents Atmospheric Pressure Metalorganic Chemical Vapor Deposition(AP-MOCVD)growth of GaAs/Al-xGa_(1-x)As multiquantum wells for the study of intersubband transition.The multiplequantum well structures are characterized by using cross-sectional transmission electron microscopy(TEM)and low temperature photoluminescence(PL),which are in consistent with the designed parameters.The in-frared absorption from intersubband transitions between the bounded- ground state and the extended excitedstate in GaAs/AtGaAs quantum wells shows peak at 10 μm with FWHM 250 cm~(-1).The absorption peakpositions are in agreement with the calculated results based on the envelope function approximation. 相似文献
979.
The role of the V-III ratio during growth on the optical and electrical properties of AlxGa1-x As laser material grown by metalorganic chemical vapor deposition has been investigated. Controlled studies involving more
than twenty growth runs show that this parameter has a profound influence on both device performance and reliability. 相似文献
980.
Nitride-based near-ultraviolet multiple-quantum well light-emitting diodes with AlGaN barrier layers
C. H. Kuo S. J. Chang Y. K. Su L. W. Wu J. K. Sheu T. C. Wen W. C. Lai J. M. Tsai S. C. Chen 《Journal of Electronic Materials》2003,32(5):415-418
The In0.05Ga0.95N/GaN, In0.05Ga0.95N/Al0.1Ga0.9N, and In0.05Ga0.95N/Al0.18Ga0.82N multiple-quantum well (MQW) light-emitting diodes (LEDs) were prepared by metal-organic chemical-vapor deposition. (MOCVD).
It was found that the 20-mA electroluminescence (EL) intensity of the InGaN/Al0.1Ga0.9N MQW LED was two times larger than that of the InGaN/GaN MQW LED. The larger maximum-output intensity and the fact that maximum-output
intensity occurred at a larger injection current suggest that Al0.1Ga0.9N-barrier layers can provide a better carrier confinement and effectively reduce leakage current. In contrast, the EL intensity
of the InGaN/Al0.18Ga0.82N MQW LED was smaller because of the relaxation that occurred in the MQW active region of the sample. 相似文献