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The effects of polysilicon emitter on the high frequency performance of bipolar transistors have been investigated numerically. The presence of polysilicon grain boundaries was found to slow down the response of the device. This resulted in a lower fT for polysilicon emitter bipolar transistors with a clean polysilicon/ mono‐crystalline silicon interface compared to conventional transistors with an identical emitter‐base junction depth. The interfacial oxide layer that could exist at the polysilicon/mono‐crystalline silicon interface can, depending on the relative thickness of the polysilicon and mono‐crystalline silicon emitter regions, either improve or deteriorate the high frequency performance of the device. For a mono‐crystalline silicon emitter region that is much thinner than the polysilicon emitter region, the lower the tunnelling probability of the interfacial oxide layer the better is the improvement in fT. However, if the thickness of the mono‐crystalline silicon emitter region is made larger with respect to the polysilicon emitter region, the converse can be true.

A compound emitter heterojunction bipolar transistor (HBT) structure that incorporates an additional heterojunction within the emitter for minority carrier confinement has been proposed. In this new device configuration, the single wide band‐gap emitter layer in a conventional HBT is replaced by two sub‐layers of wide band‐gap material, with the sub‐layer nearer the base having a narrower band‐gap. By means of numerical simulations, the compound emitter HBT was found to perform better than comparable conventional HBTs. With the AlGaAs(n) / GaAs heterostructure system, the optimum compound emitter HBT structure was found to be Al0.3Ga0.7As(n) ‐ Al0. 2Ga0.8As(n) / GaAs with grading at the two hetero‐interfaces. It has a low turn‐on voltage that is almost identical to that of a homojunction GaAs bipolar transistor with similar doping conditions. Compared with a conventional single emitter layer Al0.3Ga0.7As/GaAs HBT, the optimum compound emitter HBT has an enhancement in the current gain by approximately 2 folds, an improvement in the uniform current gain region from 2 to 4 decades of collector current density, and a slight increase in the unity‐gain cut‐off frequency fT by about 7 %.

The purpose of this paper is to analyze the redistribution of dopant and radiation defects to determine conditions which correspond to decreasing of elements in the considered inverter and at the same time to increase their density.

In this paper, the authors introduce an approach to increase integration rate of elements in a three-level inverter. The approach is based on decrease in the dimension of elements of the inverter (diodes and bipolar transistors) due to manufacturing of these elements by diffusion or ion implantation in a heterostructure with specific configuration and optimization of annealing of dopant and radiation defects.

The authors formulate recommendations to increase density of elements of the inverter with a decrease in their dimensions.

Optimization of manufacturing of integrated circuits and their elements.

The results of this paper are based on original analysis of transport of dopant with account transport and interaction of radiation defects.

The purpose of this paper is to analyze and optimize the formation of field-effect heterotransistors using analytical approach. The approach makes it possible to analyze mass and heat transport in a multilayer structure without cross-linking of solutions on interfaces between layers of the multilayer structure. The optimization makes it possible to decrease dimensions of the heterotransistors and to increase speed of transport of charge carriers during functioning of the transistors.

The authors introduce an analytical approach for analysis of mass and heat transport, which makes it possible to take into account at one time varying in space and time parameters of the transports (diffusion coefficient, heat conduction coefficient, etc.) and nonlinearity of processes. The approach enables analysis of mass and heat transport in a multilayer structure without cross-linking of solutions on interfaces between layers of the multilayer structure and optimises the technological process. The optimization means it is possible to decrease dimensions of field-effect heterotransistors.

In this paper the authors introduce an approach to manufacture a field-effect heterotransistor with inhomogeneous doping of channel. Some recommendations to optimize technological process to manufacture more compact distribution of concentration of dopant have been formulated.

The results are original and the paper provides an approach to the manufacture of a field-effect heterotransistor.

The purpose of this paper is to analyze the manufacturing of diffusion-junction heterorectifier with account relaxation of mismatch-induced stress. On the basis of the analysis, the authors formulate recommendations to increase sharpness of the p-n-heterojunction, homogeneity of concentration of dopant in the junction and charge carrier mobility.

The authors formulate recommendations to increase sharpness of p-n-heterojunction, homogeneity of concentration of dopant in the junction and charge carrier mobility. To formulate the recommendations, the authors analyzed the manufacturing of the junction. The authors introduce an analytical approach to analyze the manufacturing.

The authors find a possibility to increase sharpness of p-n-heterojunction, homogeneity of concentration of dopant in the junction and charge carrier mobility.

The results are original.

Recently published studies stress the importance of trade in intermediate goods. The literature on determinants of trade, however, have largely focused on the sources of comparative advantage in determining aggregate trade flows rather than trade in intermediate goods. The purpose of this paper is to examine the role of institutional quality and trade costs to explain the determinants of trade in intermediates.

The simple model is based on the model of comparative advantage in the gravity framework used by Eaton and Kortum (2002) and Chor (2010) to relate trade flows of intermediate goods to institutional parameters, factor endowments and geography. The empirical tests use a data set containing 172 countries and 17 industries spanning ten years.

The results confirm the theoretical prediction that a country with higher institutional quality has a comparative advantage in institution-intensive goods and trade costs have a negative effect on trade. The author further finds that these effects are stronger in share of trade in intermediate goods vis-à-vis final goods.

To highlight the distinct nature of trade in intermediate goods, the author separates industry trade flows as intermediate input trade and final goods (consumption goods) trade to compare the importance of different sources of comparative advantage among different types of trade flows. Unlike Eaton and Kortum (2002) and Chor (2010) who used cross-sectional data for final goods trade, the ten-year industry-level panel data are used to compare the relative importance of institutions and geography as determinants in trade in intermediate goods compared to final goods trade and capture the macroeconomic time variant factors as well as industry–country pair characteristics. A significant caveat in gravity regression is that an empirical finding may often be driven by omitted variables. Inclusion of a set of country variables such as GDP, production costs and institutional level may still allow omitted variables to bias the estimation. To avoid this problem, the author includes a fixed effect of exporter and importer as well as industry and year, instead of a set of country characteristics.

Among the prominent economic trends in recent decades is the exponential increase in flows of goods and capital driven by technological progress and falling of restrictions. A key driver of this phenomenon has been the cross-border production, foreign investment, and trade both final and intermediate goods by multinational corporations. Research has sought to understand how foreign direct investment (FDI) affects host economies. This paper reviews the main theories and empirical evidence of two streams of literature: the mechanisms by which multinational activity might create positive effects and externalities to countries and the role of complementary local conditions, also known as “absorptive capacities,” that allow a country to reap the benefits of FDI paying particular attention to the role of factor markets, reallocation effects, and the linkages generated between foreign and domestic firms. The survey focuses mainly on work related to developing countries.

This chapter provides a theory model of trade finance to explain the “great trade collapse.” The model shows that, first, the riskiness of international transactions rises relative to domestic transactions during economic downturns; and second, the exclusive use of a letter of credit in international transactions exacerbates a collapse in trade during a financial crisis. The basic model considers banks’ optimal screening decisions in the presence of counterparty default risks. In equilibrium, banks will maintain a higher precision screening test for domestic firms and a lower precision screening test for foreign firms, which constitutes the main mechanism of the model.