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1.
Fe、Na、Ni等金属杂质对半导体器件芯片有严重的负面影响,往往导致器件失效,成品率下降,必须进行有效控制处理.采用紫外荧光(UVF)法可有效检测出硅晶片及半导体器件芯片(如GaP、GaAs等)的金属杂质沾污情况,还能检测金属杂质的相对沾污量,对半导体器件芯片的生产可实现实时非破坏性的检测分析.  相似文献   

2.
本文运用速率方程对半导体激光器实现逻辑器件的基本原理进行了分析,并介绍实现半导体激光逻辑器件一些基本方法。  相似文献   

3.
本文在半导体器件理论的基础上,建立了微波对半导体件破坏机理研究的一维器件模型,讨论了有关计算机数值模拟的处理技巧,并给出了差分方程组。  相似文献   

4.
本文以我们的研究团队自1995年以来在半导体纳米线材料与物理研究中所做的科研工作为主线,从如何自下而上地规模、可控制备硅等半导体纳米线的开创性研究工作开始,着重介绍半导体纳米线独一无二的物理性质的代表性研究工作,以及它们在高品质真空电子源、新型高效光电器件、新能源器件方面的潜在应用的研究成果.最后,对半导体纳米线的未来发展前景进行了展望.  相似文献   

5.
在不同的应用领域,由于较大的功率和较高的频率冲击,对半导体器件的要求有很多情况下是矛盾的,因而单一器件无法解决这一矛盾。尽管过去和今后的器件类型很多,但今后的开关器件在600V以上的场合应用时,无外乎两三种:IGBT,IGCT和GTO。  相似文献   

6.
屏蔽对GaAs/AlxGa1—xAs异质结系统中施主结合能的影响   总被引:3,自引:2,他引:1  
对半导体单异质结系统,引入了三角势近似异质结势,考虑电子对杂质库伦势的屏蔽影响,利用变分法讨论在界面附近束缚于正施主杂质的单电子基态能量,对GaAs/AlxGa1-xAs系统的杂质态结合能进行了数值计算,给出了结合能随杂质位置和电子面密度的变化关系,并讨论了有无屏蔽时的区别。  相似文献   

7.
对半导体单异质结系统 ,引入三角势近似异质结势 ,考虑电子对杂质库仑势的屏蔽影响 ,利用变分法讨论在界面附近束缚于正施主杂质的单电子基态能量 .对 Ga As/Alx Ga1-x As系统的杂质态结合能进行了数值计算 ,给出了结合能随杂质位置和电子面密度的变化关系 ,并讨论了有无屏蔽时的区别  相似文献   

8.
余望 《科技资讯》2008,(35):34-34
半导体器件应用于不同的领域,其加工工艺和测试分析对于保证器件的性能具有重要意义。本文在分析了半导体器件生产工艺流程上,结合其测试发展现状和测试参数,对半导体器件的生产和测试基本问题进行了讨论,同时对其工艺设计过程及方法也进行了分析。  相似文献   

9.
静电放电(ESD)对半导体器件的损伤是影响电子产品可靠性的重要因素。在ESD引起的损伤中,有90%的概率会造成器件在使用现场的早期失效,因此ESD会严重影响器件的可靠性。我们用人体模型电路测量了部份CMOS电路的ESDS,对ESD失效器绊作了分析;根据被测器件的ESDS的统计分布规律,计算了CMOS器件的静电放电失效概率。  相似文献   

10.
通过对半导体器件模拟中网格划分原理的分析,提出了一种基于四叉树结构的有限元三角网格生成方法,进行了面向对象的编程实现。结果表明,这种网格生成方法是行之有效的。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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