Transition or Tradition: Imagining National R&D Innovation in South Korea

From the late 1990s, many national policies for research and development (R&D), focusing on innovation, were established in South Korea. In May 2015, the Korean government announced another bold blueprint for R&D innovation emphasizing a serious approach toward overcoming outdated ideas and practices regarding the governance of the science and technology sectors. This emphasized very high expectations for the country, though in the end it brought brutal criticism and bitter disappointment. This paper conducts a critical analysis of the discourse surrounding the notion of national R&D innovation by focusing on the case of the 2015 Government R&D Innovation Plan. Various (un)published papers were examined as mediators to reproduce, construct, and deliver a particular imagination. By analyzing not only the final policy documents but also the initial policy draft, this paper highlights a substantive discontinuity in the formation of the 2015 Government R&D Innovation Plan that illuminates different imaginations of so-called national innovation in terms of R&D. It illustrates a tension occurring in national R&D innovation in South Korea between the desire to reproduce past glory by following previous experiences and a willingness to embody semantic meanings of innovation with novel approaches. This paper reveals a discursive oscillation of imaginations in national R&D innovation which resulted in its conceptual and practical ambiguity

Interface polarization model for a 2-dimensional electron gas at the BaSnO3/LaInO3 interface

In order to explain the experimental sheet carrier density n2D at the interface of BaSnO3/LaInO3, we consider a model that is based on the presence of interface polarization in LaInO3 which extends over 2 pseudocubic unit cells from the interface and eventually disappears in the next 2 unit cells. Considering such interface polarization in calculations based on 1D Poisson-Schrödinger equations, we consistently explain the dependence of the sheet carrier density of BaSnO3/LaInO3 heterinterfaces on the thickness of the LaInO3 layer and the La doping of the BaSnO3 layer. Our model is supported by a quantitative analysis of atomic position obtained from high resolution transmission electron microscopy which evidences suppression of the octahedral tilt and a vertical lattice expansion in LaInO3 over 2–3 pseudocubic unit cells at the coherently strained interface

LaInO3/BaSnO3 polar interface on MgO substrates

We report on a new property of the LaInO3 (LIO)/(Ba,La)SnO3 (BLSO) polar interface using MgO substrates. The growth of well-formed LIO/BLSO interface structures on non-perovskite MgO substrates was confirmed by reciprocal space mapping image and transmission electron microscopy. Subsequently, we measured electrical properties as a function of the La doping rate of the BLSO layer and found that the LIO/BLSO polar interface shows conductance enhancement after the deposition of the polar LaInO3 layer on the BLSO layer, in agreement with our earlier results on SrTiO3 (STO) substrates. However, different electrical properties of the interfaces were found on MgO from those on STO substrates; we observed conductance enhancement even at the interface with undoped BaSnO3 (BSO) on the MgO substrates. We attribute such different behavior to the difference in the Fermi levels of BSO on MgO and STO substrates, either due to the larger donor density or the smaller acceptor density in BSO on MgO. Using such a nominally undoped interface, we fabricated the field effect transistors and presented their performances with Ion/Ioff ∼ 109

High-k perovskite gate oxide BaHfO3

We have investigated epitaxial BaHfO3 as a high-k perovskite dielectric. From x-ray diffraction measurement, we confirmed the epitaxial growth of BaHfO3 on BaSnO3 and MgO. We measured optical and dielectric properties of the BaHfO3 gate insulator; the optical bandgap, the dielectric constant, and the breakdown field. Furthermore, we fabricated a perovskite heterostructure field effect transistor using epitaxial BaHfO3 as a gate insulator and La-doped BaSnO3 as a channel layer on SrTiO3 substrate. To reduce the threading dislocations and enhance the electrical properties of the channel, an undoped BaSnO3 buffer layer was grown on SrTiO3 substrates before the channel layer deposition. The device exhibited a field effect mobility value of 52.7 cm2 V−1 s−1, a Ion/Ioff ratio higher than 107, and a subthreshold swing value of 0.80 V dec−1. We compare the device performances with those of other field effect transistors based on BaSnO3 channels and different gate oxides

Creating Tunable Mesoporosity by Temperature???Driven Localized Crystallite Agglomeration

A new synthetic approach for tunable mesoporous metal???organic frameworks (MeMs) is developed. In this approach, mesopores are created in the process of heat conversion of highly mosaic metal???organic framework (MOF) crystals with non-interpenetrated low-density nanocrystallites into MOF crystals with two-fold interpenetrated high-density nanocrystallites. The two-fold interpenetration reduces the volume of the nanocrystallites in the mosaic crystal, and the accompanying localized agglomeration of the nanocrystallites results in the formation of mesopores among the localized crystallite agglomerates. The pore size can be easily modulated from 7 to 90 nm by controlling the heat treatment conditions, that is, the aging temperature and aging time. Various proteins can be encapsulated in the MeM, and immobilized enzymes show catalyst activity comparable to that of the free native enzymes. Immobilized ??-galactosidase is recyclable and the enzyme activity of the immobilized catalase is maintained after exposure to high temperatures and various organic solvents