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141.
颜永美 《厦门大学学报(自然科学版)》1990,29(4):400-405
本文报道了应用变温光伏方法对半导体表面能级,表面态密度的非破坏性测量原理。通过一定的模型简化,将Shockly-Read体复合理论应用于表面,建立起P型半导体表面态对少子电子的俘获截面估算公式。并以P型Si单晶样品进行验证,所得结果同有关报道一致。 相似文献
142.
本文根据非晶半导体中的荷电悬挂键模型,用统计力学的方法推导出三种荷电缺陷中心的分布函数,并由此得到系统的费米能级和荷电中心上平均电子数的关系式。通过计算电子由一种缺陷中心向另一种缺陷中心的跳跃几率,解释了非晶半导体中的低温带隙跳跃导电问题。 相似文献
143.
将嵌入式操作系统W indows CE.net应用于非晶成带控制系统的开发,针对开发过程中的难点及影响系统性能的主要因素,提出了相应的解决方案,试验结果表明,系统的实时性、可靠性有明显提高,为提高非晶带材质量打下了良好的基础。 相似文献
144.
DILUTED MAGNETIC SEMICONDUCTORS(DMSS)ARE FORMED BY PARTIAL REPLACEMENT OF THE CATIONS OF THE NONMAGNETIC SEMICONDUCTORS BY MAGNETIC TRANSI-TION-METAL IONS.THE ADVANTAGES OF DILUTED MAGNETIC SEMICONDUCTORS ARE THE INTERACTION BETWEEN THE SPIN OF THE HOLES … 相似文献
145.
在第一原理框架下,采用赝势平面波方法计算研究了Mg2Si晶体的晶胞常数、状态方程和声子谱等性质,得到的晶胞常数与实验值和前人的计算值是一致的.研究发现,反萤石结构Mg2Si,反氯铅矿结构Mg2Si和Ni2In型Mg2Si分别在压强为0~6 GPa,7.5~20.2 GPa和21.9~40 GPa范围内能够保持结构稳定.三种Mg2Si同质异相体的稳定性由高到低应该是:反萤石结构Mg2Si>反氯铅矿结构Mg2Si>Ni2In型Mg2Si.利用晶格动力学方法计算了三种同质异相体的声子谱. 相似文献
146.
A series of 60~nm thick indium oxide thin-films,all amorphous as determined by x-ray diffraction,were found to have physical and electrical properties that depended on the temperature of deposition.The carrier mobility and flm conductivity decreased with decreasing deposition temperature;the best electrical properties of high mobility and conductivity were observed at a deposition temperature just below the temperature at which crystalline films formed.The density of the flm also decreased with deposition temperature from 7.2g/cm3 at+50℃ to 5.3g/cm3 at 100℃. 相似文献
147.
Yeping Li 《武汉大学学报:自然科学英文版》2008,13(2):141-147
In this paper, the asymptotic behavior of the global smooth solutions to the Cauchy problem for the one-dimensional nonisentropic
Euler-Poisson (or full hydrodynamic) model for semiconductors, where the energy equation with non-zero thermal conductivity
coefficient are contained, is discussed. The global existence of smooth solutions for the Cauchy problem with small perturbed
initial data is proved. In particular, that the solutions converge to the corresponding stationary solutions exponentially
fast as t → ∞ is showed.
Biography: LI Yeping(1972–), male, Associate professor, Ph.D., research direction: nonlinear partial differential equations. 相似文献
148.
Cd5Se95–xZnx(x=0, 2, 4, 6) glassy alloy has been prepared by a melt-quenching technique. Thin films were deposited by thermal coating unit on ultraclean glass substrate under a vacuum of 10–6Torr. The absence of any sharp peaks in the X-ray diffraction confirms the amorphous nature of thin films. The frequency and temperature dependence of dielectric constant and dielectric loss in the frequency range of 1 kHz to 1 MHz and in the temperature range of 290–370 K were studied. Dielectric dispersion was observed when Zinc(Zn) was incorporated into the Cd–Se system.The increase in dielectric parameter with Zn concentration may be due to increase in defect states. The DC conductivity has been reported to investigate the effect of Zn concentration on DC conduction loss. The results are interpreted in term of dipolar theory for Cd5Se95 and Cd5Se93Zn2samples, while the remaining samples have been explained on the basis of DC conduction loss. It was also observed that the DC conductivity increased with the increase of Zinc concentration, which may be due to the decrease in the band gap near Fermi level. 相似文献
149.
测量了正电子在化学沉积的非晶态Ni-P合金镀层中的透射强度,借此求得正电子在该镀层中的有效质量吸收系数和注入剖面。研究了磷含量和热处理对化学沉积和电沉积的非晶态Ni-P合金结构缺陷的影响。 相似文献
150.
Cheng Lin Liuzhang Ouyang Renzong Hu Jun Liu Lichun Yang Huaiyu Shao Min Zhu 《自然科学进展(英文版)》2021,31(4):567-574
To promote substantially the performances of red phosphorous(P) anode for lithium and sodium-ion batteries, a simple plasma assisted milling(P-milling) method was used to in-situ synthesize SeP2/C composite. The results showed that the amorphous SeP2/C composite exhibits the excellent lithium and sodium storage performances duo to the small nano-granules size and complete combination of selenium(Se) and phosphorous(P) to generate Se–P alloy phase. It was observed that insid... 相似文献