Understanding the electrical behaviors in van der Waals heterostructure field-effect transistor based on band alignment

Van der Waals heterostructures based on 2D layered materials have been extensively studied because their unique electronic properties, which can be controlled by optimally selecting the band alignments. Although the rectifying behavior is usually observed in output characteristics of these heterostructures, the underlying transport mechanism have not been fully understood. Here, we investigate transport properties of multilayer MoTe₂/SnS₂ heterostructure field-effect transistor (hetero-FET) fabricated by exfoliating each material and manually stacking them and observe gate-tunable diode-like current rectification. With the qualitative band analysis, we noticed that the interfacial barrier by band bending plays a crucial role to realize the transport properties of hetero-FETs, especially rectification behavior. Our experimental study offers the inspiration for understanding the transport behavior and reference to novel hetero-FETs.