Kyushu University · 재료과학
Phongsaphak Sittimart 교수의 연구실은 고온·고방사선 환경에서도 안정적인 전자소자 구현을 목표로, 다이아몬드 기반 반도체 소자 및 이종접합 구조에 대한 연구를 중심으로 전개하고 있습니다. 특히 p형 다이아몬드와 n형 Ga₂O₃, FeSi₂ 등 다양한 반도체와의 이종접합을 통해 고성능 광검출기, 슈트키 바리어 다이오드, 고내구성 전력소자 등 다양한 응용을 탐색하고 있습니다. 고온에서의 안정성과 높은 내구성을 확보하기 위한 다이아몬드 기반 버퍼층 및 표면 제어 기술 개발도 핵심 과제입니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Heterojunctions consisting of p-type diamond substrates and thin exfoliated n-type β-Ga2O3 layers were fabricated at a low temperature using a direct-bonding technique. We have fabricated p+-diamond/n-Ga2O3 (p+–n) and p-diamond/n-Ga2O3 (p–n) structures with different B concentrations in diamond. The p+–n heterojunction exhibited Ohmic behavior, resulting from p+-diamond behaving as a metallic layer. As for the p–n heterojunction, it showed clear rectifying action as a conventional bipolar action
Abstract Due to the limits of the physical properties of conventional semiconductors against harsh environments, seeking a suitable material for next‐generation photoconversion devices with high‐temperature stability and strong radiation hardness has become a hot issue. Here, visible‐light photodetectors are fabricated on an N‐doped diamond. Their visible‐light detection via charge‐neutralized impurity levels including multi‐complex mid‐gap states induced crystal defects shows photosensitivity o
Abstract In this study, pseudo-vertical diamond Schottky barrier diodes (SBDs) were fabricated on heteroepitaxial substrates and a metal impurity-incorporated buffer layer to suppress killer defects was inserted. All SBDs exhibited excellent rectifying actions with suppressed leakage current. The in-plane uniformity was improved after the insertion of the buffer layer. Forward characteristics were fitted by thermionic emission theory and Tung’s model in the temperature range from 300 to 480 K. T
Abstract In this work, we demonstrate the first achievement in heteroepitaxial growth of β -Ga 2 O 3 thin films on single crystalline diamond (111) wafers using RF magnetron sputtering. A single monoclinic ( β -phase) structure with a monofamily { <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mn>2</mml:mn> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> 01} plane was obtained. XRD pole figure shows ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/Math
n-Type nanocrystalline FeSi2/p-type Si heterojunctions were formed by using facing-target direct- current sputtering at room temperature. The J-V characteristic results revealed that the reverse leakage current is large and the response under illumination of near-infrared light is very weak. The capacitance-voltage-frequency (C-V-f) and conductance-voltage-frequency (G-V-f) measurements were carried out at room temperature in order to estimate the series resistance (Rs) by using the Nicollian-Br
In this study, n-type β -FeSi 2 /p-type Si heterojunctions, inside which n-type β -FeSi 2 films were epitaxially grown on p-type Si(111) substrates, were created using radio frequency magnetron sputtering at a substrate temperature of 560°C and Ar pressure of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mn fontstyle="italic">2.66</mml:mn><mml:mo>×</mml:mo><mml:msup><mml:mrow><mml:mn fontstyle="italic">10</mml:mn></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn fontstyle="i
Pseudo-vertical diamond Schottky barrier diodes (SBDs) were fabricated on a CVD-grown diamond substrate. The radiation hardness of the diamond SBDs was examined using hard X-ray irradiation at a radiation absorption dose of 10 MGy. Before the irradiation, ideality factor (n), Schottky barrier height (ϕ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">b</inf>), breakdown voltage, and breakdown field (E<inf xmlns:mml="http://www.w3.org/1998/Math/MathML"
