 |
Investigation of Trap Mechanisms Causing Random Telegraph Noise in Ultra-Scaled MOSFETs
CHEN Jiezhi / HIRANO Izumi / MITANI Yuichiro
Random telegraph noise (RTN), a physical phenomenon that causes variations in transistor operating current, has become one of the most important issues accompanying the shrinkage of transistors in recent years. In this context, attention is being increasingly focused on the effects of RTN on the properties of complementary metal-oxide semiconductor (CMOS) image sensors and NAND flash memories, particularly those related to reliability.
Toshiba is working to gain a further understanding of the physical mechanisms of RTN to improve the reliability of devices. We have now performed a systematic investigation of trap mechanisms causing RTN through experiments using ultra-scaled planar MOS field-effect transistors (MOSFETs). From the results obtained, we have confirmed that traps causing RTN are mainly classifiable into neutral and attractive traps, that the energy distributions of neutral traps are around 100 meV higher than those of attractive traps, and that neutral traps have a much greater impact on threshold voltage shifts. These results contribute to understanding of the trap forming process, and will assist in guiding optimization of fabrication processes to ensure high reliability. Single-Nanometer-Scale Patterning Technologies Applying Self-Assembling Materials
SASAO Norikatsu / YAMAMOTO Ryosuke / SUGAWARA Katsuya
A self-organizing phenomenon in diblock copolymers, which can spontaneously form regular single-nanometer-scale patterns, has been a focus of attention as a next-generation lithography technology. However, as this pattern formation is the result of a naturally occurring process, it is necessary to control the uniformity and positioning accuracy of such self-organized patterns in order to apply them to the semiconductor device fabrication process.
Toshiba has developed the following technologies for next-generation lithography and beyond: (1) a solvent-annealing method to uniformly arrange self-assembling materials with a dot diameter of less than 10 nm, and (2) a self-organizing technology guided by prepatterns formed on the substrate to control both the uniformity and position of patterns. We have confirmed that precisely oriented patterns can be successfully transferred onto a substrate by utilizing these technologies. Specification Mining Technology for Automatically Inferring Software Specifications from Source Code
IMAI Takeo / SAKAI Masahiro / IWAMASA Mikito
Correspondence between a program and its specification is essential for efficient redesign and reuse of software.
Toshiba has been developing a technology for mining latent specifications from a given program and reflecting them in the original specification documents. This technology enables developers not only to acquire latent information that is useful for future development and reuse, but also to keep specifications up to date. As part of this work, we have developed a new technology for automatically inferring preconditions from programs; that is, conditions that a program assumes in order to perform its intended function. We have conducted experiments on a prototype tool for C language, and confirmed its ability to obtain generic specifications similarly to or more effectively than by human effort. Understanding of Redistribution of Inlet Temperature Distortion in Gas Turbines Based on High-Order LES
Debasish BISWAS
Gas turbines, which serve as combined-cycle power generation equipment along with steam turbines, must operate at high temperatures to achieve high efficiency. In particular, the demand for increased cycle performance of gas turbines creates a severe heat load in the first turbine stage, and the mean flow temperature is usually well above the limit supported by the surrounding materials.
To design efficient cooling of high-temperature gas turbine blades, Toshiba has been developing a numerical simulation technology, based on a high-order large eddy simulation (LES) turbulence model, to understand the physical phenomena associated with the temperature redistribution behavior of the highly unsteady and distorted temperature field from the combustor to the turbine inlet. We have confirmed the effectiveness of our newly developed simulation technology through experiments and simulations, especially in the area of the rotor. This numerical simulation technology is expected to contribute to the development of next-generation gas turbine generators with increased efficiency. Combiner for Head-Up Display Systems Using Translucent Fresnel Reflector
HORIUCHI Kazuo / SHIMAKAWA Shigeru / OKADA Naotada
The introduction of head-up display (HUD) systems, which project images on the windshield of an automobile, is expected to contribute to a reduction of traffic accidents as drivers can see the images with minimal eye movement, allowing them to keep their eyes on the road and background. However, the large size of the projection unit has made it difficult to install HUD systems in a wide variety of automobiles.
Toshiba has developed a combiner for HUD systems equipped with a translucent Fresnel reflector, which reduces the size of the projection unit to about half. The combiner makes it possible to magnify projected images without disturbing the background while maintaining the image quality, though the use of a newly developed technology to decrease ghost images. Rationalization of Global Supply and Demand Planning Utilizing Combinatorial Auction Method
MURAO Ryo / KOGA Yasutaka / SAKURAI Yuki
With expanding scale and complexity of supply chains in recent years together with the globalization of manufacturing and sales sites, totally optimized planning of supply and demand has been becoming increasingly difficult. Even if planning can be optimized, it is also difficult to realize it on a practical level without building win-win relationships among a number of internal and external partners. Accordingly, not only methods for optimization and but also those for the coordination of opposing interests are essential for future supply-chain management.
Focusing on a combinatorial auction (CA) method inspired by sociology, which is one of the optimization methods based on the multi-agent system, Toshiba, in cooperation with Kobe University, has developed a supply and demand adjustment method that can visualize adversarial relationships among manufacturing and sales sites and provide information to improve the quality of decision-making. Degradation Diagnosis Technologies for Power Distribution Facilities
MURAYAMA Kiyoko / TAMURA Tamami / MIZUIDE Takashi
The degradation of power distribution facilities depends on various conditions including the installation environment, usage status, implementation of maintenance and inspection, and so on, in addition to the duration of operation. Quantitative degradation diagnosis technologies have recently become a focus of rising expectations because gaining a correct understanding of the condition of deterioration of each piece of equipment of a power distribution facility is essential for the planning and implementation of facility maintenance and preventive measures.
Toshiba has developed two new degradation diagnosis technologies for power distribution facilities: a remaining-life assessment technology that estimates insulation resistance from the physical properties of materials used in power distribution equipment, and a grease degradation diagnosis technology that monitors the degradation index of the viscous resistance of grease used in switching devices. These technologies are contributing to the planning and implementation of maintenance and preventive measures for power distribution facilities. |
