Nanomechanical resonators fabricated by atomic layer deposition on suspended 2D materials

Abstract

Atomic layer deposition (ALD), a layer-by-layer controlled method to synthesize ultrathin materials, provides various merits over other techniques such as precise thickness control, large area scalability and excellent conformality. Here we demonstrate the possibility of using ALD growth on top of suspended 2D materials to fabricate nanomechanical resonators. We fabricate ALD nanomechanical resonators consisting of a graphene/MoS$_2$ heterostructure. Using AFM indentation and optothermal drive, we measure their mechanical properties including Young's modulus, resonance frequency and quality factor, showing similar values as their exfoliated and chemical vapor deposited counterparts. We also demonstrate the fabrication of nanomechanical resonators by exfoliating an ALD grown NbS$_2$ layer. This study exemplifies the potential of ALD techniques to produce high-quality suspended nanomechanical membranes, providing a promising route towards high-volume fabrication of future multilayer nanodevices and nanoelectromechanical systems.