Elucidation of mechanical factors in degradation of electrical performance of organic semiconductor devices under mechanical deformation

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04093
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18010:Mechanics of materials and materials-related
• Research Institution: Kagoshima University
• Principal Investigator: Koganemaru Masaaki 鹿児島大学, 理工学域工学系, 准教授 (20416506)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 有機薄膜トランジスタ / 機械的負荷 / 電気特性変動 / ゲート絶縁膜

Outline of Final Research Achievements

We experimentally evaluated electrical characteristic fluctuations and electrical failure of p-type organic thin film transistors (OTFTs) under mechanical load.
In the region under low mechanical load, the rate of change in Gm (amplification rate) all decreased under bending load, in-plane tensile load, and out-of-plane compressive load. In addition, it was demonstrated that the rate of change under out-of-plane compressive load is the biggest. In the region under high mechanical load, the effects of the mechanical load on the insulation performance of the gate insulating layer of OTFTs were experimentally evaluated. As a result, it was shown that the change in insulation performance (leak characteristics) of the gate insulating layer correlated with the stress-strain characteristics of the substrate material of the OTFT.

Free Research Field

電子実装における信頼性評価

Academic Significance and Societal Importance of the Research Achievements

有機半導体デバイスは、フレキシブルな基板上に作製することで、薄くて軽く、形状変化に優れた電子機器・デバイスを実現可能にする。換言すれば、フレキシブルデバイスとして変形下（機械的負荷下）での利用が想定されており、そのような環境下でのデバイスの機械的・電気的信頼性の担保が必須となる。
本研究では、有機薄膜トランジスタ（OTFT）を対象とし、機械的負荷に起因する電気特性変動および電気的破壊を実験的に評価した。本研究成果は、有機半導体デバイス・製品の信頼性を担保する上での基礎的知見となる。