Electrical and Electronic Engineering

We engage in research and development related to the electrification and intelligence of automobiles in order to address environmental problems associated with increasing CO₂ emissions in recent years, as well as to address the coming era of autonomous driving. Our research on electrification involves efforts to improve the performance of power control units as the core component for hybrid, battery, fuel cell, and other types of electric vehicles. Similarly, we conduct a broad range of research and development from materials to systems in aims of making drive motors smaller and more efficient. Meanwhile, our research on intelligence involves the silicon photonics that serve as the eyes of mobility, as well as environmental sensing technologies that leverage advanced signal processing techniques. Through these research and development activities, we contribute to the sustainable development of mobility in the era of CASE.

Core Technologies

Power Electronics, Electrical and Electronic Materials, Electronic Devices, Electrical Equipment, Optical Engineering and Photon Science, Nanostructure Physics, Power Engineering, Control and System Engineering

Power Semiconductor Devices

SiC and GaN are attracting attention as nextgeneration power device materials due to their high energy bandgaps and critical electric fields. Although GaN devices have difficulty handling large currents, such as they found in electric vehicle applications, GaN power devices are anticipated to reduce loss and costs more than SiC devices. We developed a p-type GaN layer burying technology, which we have successfully used to demonstrate the world's first vertical structure capable of carrying large currents. Applying GaN power devices in practice, however, will also require a high quality GaN substrate, gate insulator, and p-type GaN formed by ion implantation. In order to overcome these issues, we actively promote industry-academia collaborations, and will contribute to the promotion of greater electric vehicle use.

Structure of a prototype vertical GaN power device

Environmental Sensing

Sensing technologies that detect a vehicle’s surrounding environment are essential for automated driving that enhance the safety and convenience of drivers. LiDAR has attracted attention as a key sensor that simultaneously enables ranging and object detection based on time of flight between light emitter and an object. Having mechanical moving parts, however, LiDAR systems present a variety of issues, including the need for miniaturization. We are therefore working on a phase control technology that applies an optical phased array to scan light beams while controlling the phase of the light radiated from an optical antenna, and that utilizes a Deep Neural Network to flexibly respond to the temperature of devices and other operating conditions. Electronic scanning technologies that eliminate the need for mechanical moving parts will further advance miniaturization and cost reductions and are therefore expected to expand the application of environmental sensing to factory logistics systems and a variety of other applications besides automated driving.