Abstract
Here, we present the fabrication and electrical analysis of InAs/WSe <sub>2</sub> van der Waals heterojunction diodes formed by the transfer of ultrathin membranes of one material upon another. Notably, InAs and WSe <sub>2</sub> are two materials with completely different crystal structures, which heterojunction is inconceivable with traditional epitaxial growth techniques. Clear rectification from the n-InAs/p-WSe <sub>2</sub> junction (forward/reverse current ratio >10 <sup>6</sup> ) is observed. A low reverse bias current <10 <sup>-12</sup> A/μm <sup>2</sup> and ideality factor of ∼1.1 were achieved, suggesting near-ideal electrically active interfaces. © 2013 AIP Publishing LLC.