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Today, most of the high technology products around us require high performance semiconductors, and information technology (IT) is fully utilized in these products. The IT revolution is due largely to the remarkable progress of semi‐conductor technology. Robots are expected to handle larger size wafers under various levels of vacuum and clean environments, in order to permit semi‐conductor manufacturing equipment to realize higher density and performance in the twenty‐first century. Twenty years have passed since liquid crystal Displays (LCD) were introduced into the market and now LCDs are used widely. LCDs, which are based on thin film transistors (TFT) have been used especially in displays for PCs, mobile telephones and digital cameras, and now recently in flat‐screen TVs. Under these circumstances, LCD device makers are enlarging the size of glass plates in order to achieve higher productivity. Along with these trends, the robots used in LCD manufacturing systems are required to cope with the market needs for enlarging the size of glass plates. This paper introduces the trend in the next generation of robot technology for the semi‐conductor and LCD industries, coping with larger wafers, higher density and larger LCD glass plates.

This paper aims to clarify the semi-conductive behavior of the passive layer formed in concrete environment without and with presence of chloride ions under different loading conditions. Passivation and depassivation of steel play an essential role in the subsequent stages of the corrosion process. Due to the nature of passive films on metals, they show electrochemical properties of a semi-conductor.

A C-ring model was proposed in this experiment to induce stress on the specimens. Specimens under different levels of compressive and tensile loadings were exposed to chloride-free and chloride-contaminated solutions and their semi-conductive behavior was investigated using Mott–Schottky technique.

Irrespective of the type and magnitude of the applied load, the passive film on rebars in simulated concrete pore solution is a highly disordered n-type semi-conductor. In all specimens, the presence of chloride ions decreases the slope of the Mott-Schottky plots, the donor density and the space charge layer thickness, which leads to a thinner passive film. Results indicate that steel specimens immersed in chloride-free pore solution under tensile loadings passivate more rapidly compared to those under compressive loadings. However, the situation in chloride-contaminated solution is different, and steel under tensile stress exhibits more corrosion than steel under compressive stress or under no load.

Reinforced concrete structures inevitably experience variable mechanical loads, and continuous degradation from aggressive environments. Therefore, it is imperative to study the synergic impact of different types of mechanical loadings and exposure to chloride ions on this process. This paper fulfils this need.

The purpose of this paper is to discuss whether the three knowledge sources, knowledge input, knowledge spillover and knowledge absorptive capacity, really increase the innovation performance of firms in the Taiwan IC design industry, one of the most important knowledge‐intensive business services (KIBS) industries in Taiwan.

Based on the knowledge‐based theory, this study uses pooled regression analysis and tests with fixed effect model to analyze the influence of three knowledge sources on innovation performance in the KIBS sector.

The results demonstrate that: knowledge input is positively related to innovation performance; knowledge spillover effect is partial positively to innovation performance; and knowledge absorptive capacity is positively related to innovation performance.

The paper advances the concept of absorptive capacity by defining it as the interactions between knowledge input and knowledge spillover and refines the measurement of absorptive capacity as the multiplication of knowledge input and knowledge spillover effects. Moreover, knowledge spillover effects and knowledge absorptive capacity are both divided into four kinds which help us distinguish clearly different sources of knowledge spillover and absorptive capacity. In addition to that, this study also contributes to the empirical evidence to innovation activities by using firm‐level micro data.

In this paper, we examine the comparative advantage of Korea and China while focusing on their technology level. The three digit SITC (Standard International Trade Classification) data is classified by technology level and the revealed comparative advantage (RCA) is derived from 1992-2009 by using UN COMTRADE data. For careful interpretation of the comparative advantage and technology levels, we also examined intra-industry trade and unit values of bilateral Korea-China trade, and semi-conductor industry technology. We found that the revealed comparative advantage has moved from low technology products to high technology products in Korea. China still maintains a comparative advantage in low technology products such as textiles and clothing, but at the same time, China’s high and medium-high technology products have recently gained a comparative advantage. The perception that China only has a comparative advantage for labor intensive products with low technology should be changed based on our analysis. However, China’s advancement in technology should not be overestimated. When comparing the unit value of basic materials of Korea’s and China’s exports, we found that Korea’s export product prices are on average higher than that of China’s, although the gap is reducing. A wider technology gap between Korea and China still exists in the semi-conductor industry, which is one of the most advanced high technology industries throughout the world.

In even the most lucid literature on semi‐conductors, the complexity of electrons, holes, energy levels, acceptors, donors, and so on tends to swamp any understanding of the basic principles. This, we may say, is almost too difficult for us, so it is bound to be too difficult for our students. We then get round the problem by stating categorically that holes exist, that they have the properties of positive charge carriers, and leave it at that to get on to the circuitry.

Having established the main modes of conduction in a p‐n junction (Part 2 of this article see last issue) and considered why it acts as a rectifier, it is useful to come down to earth and describe how the device is manufactured.

Automating the plants of semi‐conductor manufacturers and other ‘super‐clean’ environments seems an obvious market for robots, but it is a complicated one full of pitfalls and challenges for the unwary, as Stephen McClelland explains.

The aim of this paper is to present two independent ways in which a simple approximation to a Green's function for a differential equation can be used to improve the performance of well‐known iterative methods for linear equations.

An integral identity is derived by the method of Marchuk for the continuity equation of a carrier current in a semi‐conductor device. The coefficients of this identity are then approximated systematically. The terms involving the discretization of the carrier current turn out to be the same as those in the well known finite difference scheme of Scharfetter and Gummel, while those involving the recombination term are different. It is suggested that this new finite difference scheme will perform significantly better than the Scharfetter‐Gummel scheme especially in regions of the device where the net recombination is sharply peaked.

The basis of most semi‐conductor devices is the p‐n junction. Here p‐type material is brought into contact with n‐type material by a suitable process so that between the two types of material we have a zone of transition — the depletion layer. This layer spans the region where purely p‐type properties change to purely n‐type. On one side of the layer there are many holes in the valence band and on the other there are many electrons in the conduction band. How we present this state of affairs to the student may be open to question, but, as electrons are the particles which move, it is considered better to represent the conduction electrons as possessing higher energy, i.e. to let electron energy be considered to be positive upward in any model or diagram produced to explain the p‐n junction and its rectifying properties.