透過氧缺陷調控探索氧化物薄膜中電荷載子於二極體之應用

Abstract

隨著近期大數據與人工智慧的迅速發展，運算效能需求的提升不僅增加了對運算晶片的需求，也推動了電晶體的發展，因此PN接面的研究變得非常重要。 PN接面是p-type和n-type半導體材料之間的緊密接觸，因此接面材料的選擇對於電性和其他特性的研究至關重要。傳統上，控制半導體材料的p-type和n-type屬性通常是通過改變掺雜物的類型和濃度來實現的，例如在矽晶片的生長過程中，通過掺雜3A或5A族元素來製造p-type或n-type矽基半導體。而將氧化物做為半導體材料時也不例外，氧化物的PN特性除了可以通過控制掺雜物和濃度來實現，亦可以通過控制氧化物中的氧缺陷生成量來調節。本研究將從缺陷化學的角度切入，研究氧化物介面缺陷濃度與環境氧分壓之間的關係，進而了解氧分壓對PN特性的影響。我們使用脈衝雷射沉積方法生長ZnO和STO兩種常見的氧化物薄膜，並藉由改變退火過程中的環境氧分壓，觀察該氧分壓對薄膜PN接面的電性變化。最後透過計算缺陷濃度與電位的空間分布，評估此觀點的可行性。

With the recent rapid development of big data and artificial intelligence, there has been an increased demand for computational power. This not only has led to an increased demand for computational chips but also driven the development of transistors, making research on PN junctions extremely important. A PN junction refers to the close contact between p-type and n-type semiconductor materials, and the choice of materials for the junction is crucial for studying their electrical properties and other characteristics. Traditionally, controlling the p-type and n-type properties of semiconductor materials is achieved by modifying the type and concentration of dopants. For example, in the growth process of silicon wafers, elements from the 3A or 5A groups are doped to create p-type or n-type silicon-based semiconductors. The same holds true for oxide materials when used as semiconductor materials. The PN properties of oxides can be achieved not only by controlling the type and concentration of dopants but also by manipulating the generation of oxygen defects in the oxide material. In this study, we approach the topic from the perspective of defect chemistry to investigate the relationship between defect concentrations at oxide interfaces and environmental oxygen partial pressure, thereby understanding the influence of oxygen partial pressure on PN properties. We grow ZnO and STO, two commonly used oxide thin films, using pulsed laser deposition, and we observe the changes in the electrical properties of the thin film PN junctions by varying the environmental oxygen partial pressure during the annealing process. Finally, we evaluate the feasibility of this perspective by calculating the spatial distribution of defect concentrations and potentials.