現在地
Home > Project - Semiconductor Radiation Effects Research

Project - Semiconductor Radiation Effects Research

> Japanese Page

face ohchima

Project Leader Takeshi Ohshima

 

    Next-generation technologies, for example, new concept computers substitute for super computers to solve issues on limitation of miniaturization of semiconductors and increase of power consumption, perfect cryptographic communications for enhanced information securities and sensing with high accuracy and high sensitivity for research in life science and material science, are required for our life to be more comfortable, safer and more secure. Technologies based on quantum effects, thus, quantum computing, quantum information and quantum sensing, are expected to be solve those issues. In order to realize those technologies, qubits operating with robust and steady are indispensable. We study defect engineering using ion and electron beams for creation of defects which act as qubits and quantum sensors in wide bandgap semiconductors such as diamond and silicon carbide (Si).
    When semiconductor materials and devices are irradiated with radiations such as ion, electrons and gamma-rays, degradation of their characteristics, nondestructive and destructive malfunctions occur. For example, degradation of solar cells, flip-flop of memories and destruction of power devices in satellites are observed in space radiation environments. We study radiation response of solar cells and semiconductor devices to reveal the radiation degradation/malfunction mechanisms and in addition, establish radiation resistant technologies for development of long lifetime and highly reliable semiconductor devices that can be used in high radiation environments such as space, nuclear and accelerator facilities.

1.Defect Engineering of Wide Bandgap Semiconductors

Single Photon Source (SPS) has a unique characteristics that it emits one photon when it excited by one photon. We can realize quantum computers which have extremely higher calculation capability than current computers, very bright photonic devices of which size is well controlled in nano meter level and high sensitive magnetic senseors if we can control spin and luminescence of defects acting as SPS. Defect centers which act as SPS can be created in wide bandgap semiconductors such as diamond and Silicon Carbide (SiC). We are developing creation techniques of negatively charged nitrogen vacancy (NV-) centers which act as SPS in diamond using ion and electron beams. We also characterize spin and luminescence of NV- centers. In addition, we create defects in SiC using ion and electron beams and study such defects from the point of vies of SPS.

2.Super Radiation Hardnened Electronics for Applications of Nulear and Accelerator Facilities

Silicon Carbide (SiC) is regarded as a promising candidate for radiation resistant devices. For applying SiC to such radiation resistant devices, it is important to understand radiation response of their electrical characteristics. So, we study the effects of radiations on SiC devices.

3.Radiation Effects on Electronic Devices and Solar Cells for Space Applications

The electrical characteristics of devices such as LSI and Solar cells used in space are affected by incidence of high energetic particles such as heavy ions, protons and electrons. Thus, the performance of such devices is degraded and/or the malfunction occurs. Therefore, the reliability and/or lifetime of electronic devices in radiation environments have to be clarified before launch. Also, the development of electronic devices with high radiation resistance is important. So, we study radiation effects in electronic devices for space applications.