Papers by Keyword: Statistics

Abstract: Several defects were analyzed through the manufacturing chain along with their impact on devices. High kill rate of micropipes were seen on both Diodes and MOSFETs as expected. The purity of micropipe detection was found to be affected by the presence of inclusions. Inclusions were successfully sub-classified and separated out from micropipes, based on their location depth from the wafer surface. The effect on devices was found to relate to how deep the inclusion was located, with the ones at the surface having the biggest impact. Various sources of Stacking Faults (SFs) were reported, with Basal Plane Dislocations (BPDs) in the crystal being a major contributor. Higher local densities of BPDs were found to have a more detrimental effect. SFs were sub-classified using the wavelength of each peak. The effect of both overall SFs and each SF sub-type on devices was determined, each sub-type having different effect on the device. Various ways of mitigating the effects of defects and dislocations are demonstrated. Reducing killer defects, SF nucleation probability, and BPDs propagation by epitaxial process optimizations are shown. Resilience up to 3500A/cm² against bipolar degradation is demonstrated by using an engineered buffer layer. Process and device design optimizations show high resiliency against crystal and epi defects and dislocations, with improved yield and lower leakage.

Abstract: The detection and classification of SiC Epitaxial extended defects was refined to separate out defective areas that influence device characteristics. Die level defect localization along with defect area calculations were performed on millions of die across product groups. A clear impact of non-killer defects was observed, especially with increasing density and defective area in the die. Specifically, all types of stacking faults caused higher leakage, lower blocking voltage, and increases in ON resistance and threshold leakage. Furthermore, MOSFET devices were affected to a much larger extent than diode devices. Testing die with higher numbers of defects provides insight on device reliability. Analyzing devices with specific counts of BPDs let us quantify the amount of bipolar degradation caused drift by product/voltage classes.

Abstract: Multi-channel defect detection in epitaxial SiC layers is used to detect and classify various extended defects. The effects of the killer defect category are analyzed on hundreds of production diode and MOSFET wafers. Invariably, the number of these killer defects sets the yield entitlement for each wafer, and electrically, they fall into a few expected failure bins depending on their position on the die. A variety of non-killer defects like Bar Stacking Faults (BSFs), V-type defects, isolated micro-pipe related bumps, stacking faults, scratches and deep pits are identified in over thousand die each, and their effect on fully fabricated diode and MOSFET products are determined at wafer sort. A very high percentage of the die containing these non-killer defects pass all electrical tests including the rigorous Unclamped Inductive Switching (UIS) testing. Specifically, a population of electrically passing die, containing BSFs, are identified and packaged for High Temperature Reverse Bias (HTRB) tests. Every BSF containing die passes both forward and reverse 1000-hour HTRB drift tests.

Abstract: Information on the influence of the state of the production process of production and the uncertainty of the measurement on the decision on the product's suitability is given. It is shown on the example of brick production that the decision to accept a batch of bricks, taking into account the measurement uncertainty under unstable condition of the production process, may be erroneous. Three variants of the state of the production process for the production of 100-grade brick are considered. The first option - the average value of compressive strength does not coincide with the middle of the tolerance field, the production process is characterized as unstable, the second option - the average value of compressive strength does not coincide with the middle of the tolerance field, a greater value of the spread of the indicators compared with the first version and is characterized as an unstable process, the third option is the average value of the tensile strength, and compression coincides with the middle of the tolerance field, is characterized as a stable and reproducible process. It is established, that, if the production process is in a state of statistical controllability, i.e. stable, then taking into account the uncertainty of measurement, the brick grade remains 100. In an unstable process with an increase in the value of the standard uncertainty of type A, the controller's decision to identify the brand of brick 100 may be erroneous. Statistically stable and reproducible process makes it possible to increase the reliability of product quality control and to avoid mistakes in deciding on the rejection of products.

Abstract: The paper deals with application of simulation software for optimizing lines dealing with the manufacture of doors a car. The introduction is described briefly compare advantage and disadvantages of applying simulation in different processes [2]. It also includes a brief description of the manufacturing process of a car doors. Based on the results of simulation software Tecnomatix Plant Simulation evaluates two potential variants of optimization [10].

Abstract: Based on the meteorological data collected from 3 stations in recent 10 years in Fushun region, the reference crop evapotranspiration was calculated with the Penman-Monteith equation recommended by FAO in 1990. The evapotranspiration of the region was analyzed using linear regression analysis based on software of SPSS. The results showed that the linear correlation was evident between the evapotranspiration data of stations, but it is not significant for the linear correlation between the stations, neither between the stations. The result will be helpful to analysis of the space distributions of the reference crop evapotranspiration in the region.

Abstract: The characteristic value of gray level co-occurrence matrix to extract can well express the information of texture. Co-occurrence matrix provides the information of image grayscale, interval and change. According to the co-occurrence matrix, it can calculate the corresponding characteristic values of eigenvalue, which can express the texture information of the image. This is thesis designed extraction software a for textile fabric texture feature, and the internal principle is the using of gray level co-occurrence matrix and Matlab programming.

Abstract: The publication deals with the test equipment for measuring properties of conveyor belts of pipe conveyor. The device was designed with the aim of setting tension force and measuring the contact forces at positions which correspond to positions of idlers at hexagonal idler housing of pipe conveyor. Contribution gives an overview of experimentally obtained statistics, relations and relationships. Presented several results of analyses focused on potential context between the information brought by experiments and practical application.

Abstract: As the development of WoT(Web of Things), a large mount of services emerge. How to make full use of these services is a hot research area nowadays. This paper focuses on making these services more valuable in WoT Smart Home scenario. In this paper, we propose a model called service selection model based on rule and statistics into WoT Smart Home scenario. It is a combination of rule model and statistics model. It not only automatizes the service selection process by adopting statistics algorithm, but also dramatically improves the accuracy of this process by combining rule and statistics. Further more, it saves efforts of the annotation of service rules greatly. We carry out some experiments to verify the efficiency of this model by comparing with rule model and statistics respectively. The results show that the combination model can efficiently and precisely select services.

Abstract: Process modelling is the concise description of the total variation in one quantity, y, by partitioning it into a deterministic component given by a mathematical function of one or more other quantities, x1, x2... plus a random component that follows a particular probability distribution. The models are material or immaterial systems, which represent other systems, so that it may be possible to manipulate the built structures and their states. The main elements of a simulation are: attributes (describe and differentiate entities), variables (system characteristics), resources (whose capacity can be variable), tails (seen in case of unavailability of resources) and statistical accumulators (measure needed indicators). The new cluster model used in the present paper is a "Five for all" type, which is based on the American concept of "Smart community". Following the regional SWOT analysis, we choose an enterprise (SME), a member of the regional innovation cluster, whose activities will be modelled using the Arena software: distribution and processing of steel products (sheet, profile, pipe, concrete, steel, stainless steel, alloy with special purpose). Welded pipe production, cutting heavy plate with gas and plasma, cutting and slitting foil, shaping and reinforcing steel in coils bars, components from. Trade in petroleum products and fertilizers. Foreign trade and transport. Modelling and simulation of industrial activities profile are based on statistics regarding the lifecycle of various products and equipment involved in their manufacture.