‘Modern information technology accelerated data processing and storage, and scaled up their capacity since the introduction of integrated circuitry in the 1960s. Upon the technology-nodedriven miniaturization, we have witnessed that electronic device structure began to deviate from planar geometry and evolved into three-dimensional space, e.g., trigate FinFET and VNAND for better electrostatic control and massive data storage, respectively.
Following such device structural renovation, this talk will highlight how an emerging class of semiconductors, atomically-thin semiconductors, can be synergistically embedded to function as logic and nonvolatile memory operations in the More-Moore as well as in the More-than Moore domains. More importantly, as an integrated solution, I will introduce vapor-phase deposition (ALD and MOCVD) and a set of nanofabrication strategy tailored for target chalcogenide semiconductors and 3D device geometry. To be specific, I will initially address how our team approach to explore and solve fundamental scientific and engineering challenges in 3D adaptive MOCVD growth of 2D semiconductors and eventually monolithic integration of 2D vertical FETs in the complex device geometries.
Our recent works of hybrid-dual-gated electrochemical and multi-junction tunneling logic transistors will be followed to demonstrate field-controlled bimodal and steep-slope low-power switching, respectively.
In particular, the latter is enabled by phase-centric synthetic strategies where we achieve wafer-scale production of tin selenides (SnSe and SnSe2) in the 2D limit by utilizing a low-temperature MOCVD process. Next, I will present the wafer-scale growth of mono-elemental 2D tellurium (Te) thin films using an annealing-free, low-temperature ALD process. As-deposited Te films exhibit exceptional homogeneity, precise layer controllability, and 100 % step coverage in high aspect ratio nanostructures.
Additionally, we showcase an ALD-Te-based selector device with fast switching time, selectivity and low Vth. Capable of low-temperature processing, I will conclude with the latest research progress toward BEOL-compatible neuromorphic hardware, all based on synthetic chalcogenide thin films.