首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
半导体放电管多元胞结构模型研究   总被引:2,自引:0,他引:2  
在半导体放电管的版面设计上提出了多元胞结构版图,对多元胞结构“短路模型”进行了理论分析和实验验证,结果表明合理设计多元胞版图尺寸和p基区薄层电阻可以改善器件的转折导通特性,从而为简化半导体放电管生产工艺提供了依据。  相似文献   

2.
多元胞结构的半导体放电管浪涌能力研究   总被引:1,自引:0,他引:1  
鉴于半导体放电管工作时的最高温升决定其浪涌能力,通过对器件进行温度场模拟,可以明显地看出基片厚度、载流子浓度以及元胞数对器件温升的影响。因此对不同厚度、杂质浓度的16元胞放电管进行了浪涌实验。模拟和实验结果均表明,增加元胞数、选择均匀性好和较薄的衬底材料以及采用低扩散浓度方法可以减少放电管工作时的温升,改善放电管浪涌能力。  相似文献   

3.
本文描述了一种通道式布图算法及由此实现的开关电容(SC)电路的版图设计系统——LING85。该系统采用积木块式的元胞,行陈列的模式结构。用一维相关算法按相关元胞相距最近的原则完成行布局。分解嵌入的双层布线算法把分解后的两端子网按不交叉排序关系尽可能密集且不换层次地嵌入到各走线道,同时对穿孔作进一步处理.最后进行数据转换并完成已建库元胞的装载和连接,输出完整版图。  相似文献   

4.
应用空心阴极放电管观测铷D2线的光电流谱,发现谱线中部有凹陷出现。对凹陷出现的原因进行了分析和研究。利用此现象,将半导体激光器频率锁定于谱线凹陷的中央。  相似文献   

5.
金属陶瓷气体放电管的稳定性研究   总被引:3,自引:0,他引:3  
阐述了金属陶瓷气体放电管过电压保护原理,讨论了阴极材料和气体对放电管击穿电压的影响,提出了改进措施,研制了优良品质的放电管。  相似文献   

6.
由晶闸管短路发射极模型提出了半导体浪涌防护器的一种多元胞结构,分析了该模型的转折特性与维持电流IH。在归一化条件下,定量表述了其折衷关系,从而确定了某一工艺参数条件下的最佳D/d值,为提高SSPD的浪涌能力、改善响应特性、实现器件的规模化生产具有重要意义。  相似文献   

7.
针对常规半导体放电管在超大浪涌电流作用下,易局部过热而损坏这一问题,采用镓闭管扩散代替硼扩散、台面工艺解决二氧化硅不能掩蔽镓扩散所带来的问题、玻璃钝化工艺实现高压结面保护等方法。实验结果表明,通过镓扩散、台面刻槽、玻璃钝化和钛镍银多层金属化等工艺,提高了放电管的启动保护电压和最大浪涌电流,其最大浪涌电流达到6 kA,比设计值5 kA提高了20%。  相似文献   

8.
本文提出了集成电路芯片分析-识别系统的设计思想,并详细论述了版图-电路提取软件和电路拓扑结构检查软件的功能和算法特点.  相似文献   

9.
2Cr13不锈钢应变疲劳过程中微观结构的变化   总被引:2,自引:0,他引:2  
2Cr13马氏体不锈钢应变疲劳过程中发生了循环软化.微观结构分析表明,疲劳亚结构为位错胞状结构,但胞的特征受板条形貌、碳化物分布和循环应变幅的影响.应变幅恒定时,随循环周次的增加,微观亚结构的演变过程为:首先是可动螺型位错进行交叉滑移,将基体中的自由位错束集;然后与碳化物或板条界相连,形成壁较厚的位错胞状结构.  相似文献   

10.
应用空心阴极放电管观测铷D2线的光电流谱,发现谱线中部有凹陷出现。对凹陷出现的原因进行了分析和研究。利用此现象,将半导体激光器(0.7800μm)频率锁定于谱线凹陷的中央。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号