Fabrication of novel excitonic devices using flux-controlled sputter epitaxy and study of exciton transport in the devices

2021 Fiscal Year Final Research Report

• Project/Area Number: 18H01206
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 14030:Applied plasma science-related
• Research Institution: Kyushu University
• Principal Investigator: Naho Itagaki 九州大学, システム情報科学研究院, 教授 (60579100)
• Co-Investigator(Kenkyū-buntansha): 白谷 正治 九州大学, システム情報科学研究院, 教授 (90206293)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: エキシトントランジスタ / 酸化物半導体 / ZION / 量子井戸 / プラズマ / スパッタリング / エピタキシャル成長 / 結晶成長

Outline of Final Research Achievements

The objective of this research is to fabricate novel excitonic devices using novel materials ZION, which have been developed by the principal investigator (PI), by means of flux-controlled sputter epitaxy. In this project, we succeeded in (1) epitaxial growth of single crystalline ZION films, (2) formation of atomically sharp hetero-interfaces between ZION and ZnO, and (3) demonstration of switching operation of exciton transistors by photo-irradiation to the gate electrodes. We also discussed the mechanism of exciton transport by an external electric field. Based on the hypothesis that the main transport mechanisms are bipolar diffusion and translational motion of dipoles in a non-uniform electric field, we solved the diffusion equation with the electric field parallel to the exciton transport direction as the external force and succeeded in qualitatively describing exciton transport in the devices.

Free Research Field

電子材料，プラズマエレクトロニクス

Academic Significance and Societal Importance of the Research Achievements

本研究は，代表者オリジナル材料であるZIONが有する潜在的な高いエキシトン束縛エネルギーとピエゾ効果を，高精度フラックス制御スパッタにより発現させ，エキシトントランジスタ実用の鍵となる「室温・長寿エキシトン」を実現することを目的としたものである．本研究は，プラズマ物理の視点から準粒子の物性探究を図るという学術的新規性に加え，情報通信ネットワークの高度化への寄与等，実用的観点からも意義を有する．