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51.
We present a detailed study of a superjunction(SJ) nanoscale partially narrow mesa(PNM) insulated gate bipolar transistor(IGBT) structure. This structure is created by combining the nanoscale PNM structure and the SJ structure together. It demonstrates an ultra-low saturation voltage(V_(ce(sat))) and low turn-off loss(E_(off)) while maintaining other device parameters. Compared with the conventional 1.2 k V trench IGBT, our simulation result shows that the V_(ce(sat))of this structure decreases to 0.94 V, which is close to the theoretical limit of 1.2 k V IGBT. Meanwhile, the fall time decreases from109.7 ns to 12 ns and the E off is down to only 37% of that of the conventional structure. The superior tradeoff characteristic between V_(ce(sat))and E_(off) is presented owing to the nanometer level mesa width and SJ structure. Moreover, the short circuit degeneration phenomenon in the very narrow mesa structure due to the collector-induced barriers lowering(CIBL) effect is not observed in this structure. Thus, enough short circuit ability can be achieved by using wide, floating P-well technique.Based on these structure advantages, the SJ-PNM-IGBT with nanoscale mesa width indicates a potentially superior overall performance towards the IGBT parameter limit. 相似文献
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Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor(VDMOS) devices with composite SiO2-Si3N4 film gates are investigated.The relationships among the important electrical parameters of the samples with different thickness SiO2-Si3N4 films,such as threshold voltage,breakdown voltage,and on-state resistance in accumulated dose,are discussed.The total dose experiment results show that the breakdown voltage and the on-state resistance barely change with the accumulated dose.However,the relationships between the threshold voltages of the samples and the accumulated dose are more complex,and not only positively drift,but also negatively drift.At the end of the total dose experiment,we select the group of samples which have the smaller threshold voltage shift to carry out the single event effect studies.We find that the samples with appropriate thickness ratio SiO2-Si3N4 films have a good radiation-hardening ability.This method may be useful in solving both the SEGR and the total dose problems with the composite SiO2-Si3N4 films. 相似文献
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本文结合近几年的高考试题及模拟题,介 绍运用小正方体去解立体几何中选择、填空题 的方法及作用. 1_有助于提高洞察能力 把题中所给出的几何模型放进正方体中 去,能够起到“眼观六路,耳听八方”的作用,有 助于整体把握,直觉洞察. 相似文献
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利用自组装的毛细管电泳非接触电导检测装置建立了水杨酸(SA,羟基自由基捕获剂)及其羟基化产物2,3-二羟基苯甲酸(2,3-DHBA)和2,5-二羟基苯甲酸(2,5-DHBA)的分离测定方法。在最佳条件下10min内即可完成分离,其线性范围为0.03~15.0mg·L^-1L^-1,检出限(S/N=3)为0.01mg·L^-1,对0.7mg·L^-1混合溶液进行测定,SA、2,3-DHBA和2,5-DHBA峰面积的相对标准偏差(n=8)依次为2.9%,3.2%,3.6%。 相似文献
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