Department of Physics and Centre for Plastic Electronics, Blackett Laboratory, Imperial College London, London SW7 2AZ, U.K.
Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
Sci Adv. 2017 Mar 31;3(3):e1602640. doi: 10.1126/sciadv.1602640. eCollection 2017 Mar.
Thin-film transistors made of solution-processed metal oxide semiconductors hold great promise for application in the emerging sector of large-area electronics. However, further advancement of the technology is hindered by limitations associated with the extrinsic electron transport properties of the often defect-prone oxides. We overcome this limitation by replacing the single-layer semiconductor channel with a low-dimensional, solution-grown InO/ZnO heterojunction. We find that InO/ZnO transistors exhibit band-like electron transport, with mobility values significantly higher than single-layer InO and ZnO devices by a factor of 2 to 100. This marked improvement is shown to originate from the presence of free electrons confined on the plane of the atomically sharp heterointerface induced by the large conduction band offset between InO and ZnO. Our finding underscores engineering of solution-grown metal oxide heterointerfaces as an alternative strategy to thin-film transistor development and has the potential for widespread technological applications.
由溶液处理的金属氧化物半导体制成的薄膜晶体管在新兴的大面积电子领域具有广阔的应用前景。然而，该技术的进一步发展受到通常存在缺陷的氧化物的外电子输运性质的限制。我们通过用低维、溶液生长的 InO/ZnO 异质结取代单层半导体沟道来克服这一限制。我们发现 InO/ZnO 晶体管表现出带状电子输运，迁移率值比单层 InO 和 ZnO 器件高 2 到 100 倍。这种显著的改善被证明源于由 InO 和 ZnO 之间大的导带偏移引起的在原子尖锐异质界面上的自由电子限制在平面上。我们的发现强调了溶液生长的金属氧化物异质结的工程作为薄膜晶体管发展的替代策略的重要性，并且具有广泛的技术应用潜力。
