LOW STRESS ATOMIC LAYER DEPOSITED ALUMINA FOR NANO ELECTRO MECHANICAL SYSTEMS

摘要

A new fabrication process, test structures, and measurements of material properties are presented for atomic layer deposited (ALD) alumina (Al{sub}2O{sub}3) nanoelectromechanical systems (NEMS). ALD Al{sub}2O{sub}3 has similar electrical and mechanical properties to silicon nitride (Si{sub}xN{sub}y) and can be used in many of the same applications. Yet ALD Al{sub}2O{sub}3 is an advantageous material to use over Si{sub}xN{sub}y due to the low deposition temperature, which allows for integration with CMOS processing. Also, ALD Al{sub}2O{sub}3 has a high chemical resistance to Si etchants. In this work the stress in ALD Al{sub}2O{sub}3 is measured to be σ = 401 ± 32 MPa and σ = 445 ± 66 MPa for 100 nm and 50 nm thick Al{sub}2O{sub}3 films, respectively. The measured Young's modulus is in the range of 110-120 GPa.