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Temperature-Dependent Characteristics of GaN Schottky Barrier Diodes with TiN and Ni Anodes 下载免费PDF全文
The effect of temperature on the characteristics of gallium nitride (GaN) Schottky barrier diodes (SBDs) with TiN and Ni anodes is evaluated. With increasing the temperature from 25 to 175℃, reduction of the turn-on voltage and increase of the leakage current are observed for both GaN SBDs with TiN and Ni anodes. The performance after thermal treatment shows much better stability for SBDs with Ti N anode, while those with Ni anode change due to more interface states. It is found that the leakage currents of the GaN SBDs with TiN anode are in accord with the thermionic emission model whereas those of the GaN SBDs with Ni anode are much higher than the model. The Silvaco TCAD simulation results show that phonon-assisted tunneling caused by interface states may lead to the instability of electrical properties after thermal treatment, which dominates the leakage currents for GaN SBDs with Ni anode. Compared with GaN SBDs with Ni anode, GaN SBDs with TiN anode are beneficial to the application in microwave power rectification fields due to lower turn-on voltage and better thermal stability. 相似文献
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介绍了非近轴光束的表示理论,利用该表示理论很好地解决了非近轴光束的角动量问题,发现非近轴光束的总角动量可以严格地分解成自旋和轨道两部分,但是两者都依赖于由偏振椭圆度表征的光束的偏振状态。主要研究了柱矢量光束的角动量问题。给出了动量空间和位形空间中的柱矢量光束表达式和角动量算符表达式。通过分析两个空间中的角动量算符及柱矢量光束表达式,发现在这两种空间中,具有螺旋型相位的柱矢量光束是角动量算符沿着传播方向的分量的本征态,其本征值与偏振椭圆度无关,这为计算这类特殊光束的角动量提供了一种新方法。 相似文献
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以苯甲醛和吡咯为初始原料,经多步反应合成了5-[2,3-双(2,4,5-三甲基-3-噻吩基)马来酰亚胺-N-苯基]-10,15,20-三苯基卟啉(TPPMA)及其金属锌配合物(ZnTPPMA)与铜配合物(CuTPPMA),通过IR,MS,1H NMR和13C NMR确认了化合物的结构,并利用UV-Vis光谱探讨了化合物的光致变色性能.实验结果表明,无论在聚乙烯醇缩丁醛(PVB)膜还是在溶液中,TPPMA在254 nm紫外光照射下,没有光致变色现象,而在254和650 nm的光照下其金属配合物CuTPPMA和ZnTPPMA在溶液及PVB膜中皆可以发生可逆的光致变色反应. 相似文献
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煤岩与其他普通岩石的力学性能明显不同.为了描述煤岩体压裂岩体突变形成裂缝以及裂缝的扩展问题,基于突变理论定义了损伤变量,并建立了岩体突变过程的能量释放计算模型.基于能量守恒原理,建立了突变后微裂缝扩展的能量方程.通过对黑龙江省鸡西煤矿张晨矿区西三采区3#层右六巷区块煤样在不同压裂阶段缝内流体净压力和微裂缝扩展规律的观察分析,得到由于岩体物性参数不同,微裂缝开始破裂的时间不同,为后续裂缝演化内在混沌特征的研究提供了依据. 相似文献
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