This paper focuses on multilateral naval cooperation. To understand the importance of multilateral naval cooperation, it is necessary to answer three questions: what kind of problems are we facing; ...what kind of cooperation mechanisms are effective to deal with these problems; and which one of them is the most important? Naval cooperation amongst friendly countries needs to primarily deal with imminent threats such as the arms race and power game in this region, non-state threats and concerns about the future. To effectively deal with these threats, countries have engaged in confidence-building mechanisms by sharing information regarding various events, and by building capacity to deal with emerging threats and uneasy situations. All of these methods elaborate the importance of multilateral cooperation, and the navies of countries should cooperate actively in this network to maximise outcomes. Hence, there is great potential in the multilateral framework of the "New Alliance" which is developing in the region.
The current--voltage characteristics of Schottky barrier diodes formed on GaN(0001) free-standing substrates with net donor concentrations of $7.6\times 10^{15}$--$1.4\times 10^{17}$ cm -3 are ...discussed. The substrates were grown by hydride vapor phase epitaxy. Ni Schottky contacts were directly formed on chemical--mechanical-polished Ga-polar faces of the substrates. Nearly ideal characteristics for both directions were obtained. The ideality factors for forward characteristics are 1.02--1.05, very close to unity. The reverse characteristics agree well with calculations based on thermionic-field emission theory without any fitting parameter.
In this paper, we discusse the origin of basal-plane stacking faults (BSFs) generated in the homoepitaxial hydride vapor phase epitaxy (HVPE) growth of m-plane gallium nitride (GaN). We investigated ...the effects of seed quality, especially dislocation density, on BSF generation during homoepitaxy. The results clearly identify basal-plane dislocation in the seed as a cause of BSF generation. We realized high-quality m-plane GaN substrates with a 2-in. diameter using HVPE on low-dislocation-density m-plane seeds.
A new theoretical model has been proposed to explain the origin of the double-peak emission observed characteristically in m-plane InGaN quantum wells (QWs). Although the emission spectrum with a ...double-peak structure is generally regarded as evidence of In compositional phase separation or extended crystal defects that generate localized energy states, such crystal irregularities cannot be observed by transmission electron microscopy or three-dimensional atom probe in the QWs. It has been clarified, by our model, that only the slowly decaying tailing of the density of states can cause the double-peak structure. This is consistent with experimental results, and furthermore, the measured temperature and In composition dependences of photoluminescence spectra with the double-peak emission can also be successfully reproduced by theoretical calculation based on our model.
We carried out the selective-area growth of GaN and fabricated InGaN/GaN MQWs on non- and semi-polar bulk GaN substrates by MOVPE. The differences in the GaN structures and the In incorporation of ...InGaN/GaN MQWs grown on non- and semi-polar GaN substrates were investigated. In the case of selective-area growth, different GaN structures were obtained on GaN, GaN, and GaN substrates. A repeating pattern of and facets appeared on GaN. Then, we fabricated InGaN/GaN MQWs on the facet structures on GaN. The emission properties characterized by cathodoluminescence were different for and facets. On the other hand, for InGaN/GaN MQWs on non- and semi-polar GaN substrates, steps along the a-axis were observed by AFM. In particular on GaN, undulations and undulation bunching appeared. Photoluminescence characterization indicated that In incorporation increased with the off-angle from the m-plane and also depended on the polarity.
We carried out the selective area growths of GaN on semipolar ($20\bar{2}1$), ($20\bar{2}\bar{1}$), and related non- and semi-polar GaN substrates by metalorganic vapor phase epitaxy. By changing the ...growth parameters and directions of the SiO 2 stripe mask, the differences in GaN structures between the growths on the different substrates were investigated. In the case of the stripes $\parallel$ $a$-axis, anisotropic GaN structures with ($000\bar{1}$) and ($10\bar{1}1$) facets were obtained for all the non- and semi-polar GaN substrates. On the other hand, in the case of the stripes $\perp$ $a$-axis, isotropic GaN structures were obtained for the ($20\bar{2}1$) and ($20\bar{2}\bar{1}$) GaN substrates. However, the GaN structures between them were quite different. After 120 min of growth, $\{11\bar{2}0\}$ and ($20\bar{2}\bar{1}$) facets markedly expanded for the ($20\bar{2}1$) and ($20\bar{2}\bar{1}$) GaN substrates, respectively. Moreover, by exploiting the effect of growth temperature, the growth of a continuous ($20\bar{2}\bar{1}$) GaN layer with voids was realized.
