MoS₂ Based High-Performance FET Devices for Memory Circuits on Flexible Platform

Abstract

Two-dimensional transition metal dichalcogenides (TMDs) are fertile ground for fundamental material science and emergent applications in high-performance electronics. The mechanical flexibility of 2D materials allows their incorporation in variable form factor designs such as smart wearables and foldable electronics, where their electronic and optical properties outperform conventional flexible materials such as organic polymers. In the current work, we present high-performance ALD grown MoS2 based FET devices transferred on polyimide substrates. The growth method employs ALD to grow an MoO3 layer on a 6 inch wafer which is subsequently annealed in an H2S atmosphere to convert to MoS2. The ALD allows for excellent uniformity and because the layer acts as a template the process is scalable to larger sizes. The resulting MoS2 film is 2-3 layers thick. The film was transferred on the patterned target substrate using polystyrene assisted transfer of MoS2 layer. More than 90% device yield, excellent current ON to OFF ratio of 106 and mobility values up to 32 cm2 V-1 s-1 have been measured from micron scale devices with L/W in the range of two. We will present results on the yield and homogeneity on large area memory networks aiming for low power neuromorphic circuits