Naturally formed contacts between assorted metals and 2D TMD materials*

Novel technologies built on the properties of two dimensional transition metal dichalcogenides (TMD) require the ability to pattern, process, and contact the material in a scalable manner. However, reproducibly making quality contact to 2D materials remains a significant challenge. We have developed a technique which uses bulk transition metal contacts which act as nucleation sites and a source of material for the growth of 2D TMDs. The bulk metal remains after growth, establishing a naturally formed electrical contact with the TMD material. In the original manifestation of this technique, the contact material was limited to the transition metal of the subsequently grown TMD, however, it has been reported that various elemental metal contacts exhibit reduced Schottky barriers. We will present results from a modification of our growth process which allows for different metal contacts to be produced. A comparison between various metal contacts such as Ti-MoS₂ and Mo-MoS₂ will be presented and transport measurements will be discussed. This modification to our technique opens up the possibility of producing more complex device architectures with tailored contact properties.