Two-Dimensional (2D) Material Devices

The Koester NanoDevice Laboratory (KNDL) currently has several projects related to two-dimensional (2D) transition metal dichalcognides (TMDs). In one project, with collaborators at the University of Michigan, KNDL is exploring how to make contact to tungsten diselenide (WSe₂) transistors using TMDs by atomic-layer deposition (ALD). This work uses techniques that are extendable to 300-mm wafers and fabrication in a production enviornment. Another project involves development of production-compatible techniques to deposit high dielectric constant materials onto 2D semiconductors. Finally, in a collaboration with the University of Minnesota, the lab is developing new types of memory devices that combine ferroelectrics with amorphous oxide semiconductors. In prior work, KNDL has developed numerous novel devices and structures using 2D materials, including steep-slope tunnel transistors using black phosphorus, and gain-cell dynamic memories using molybdenum disulfide (MoS₂). The lab has also made fundamental contributions to the study of optoelectronic devices using 2D materials, including graphene optical modulators, black phosp