Density enhanced MEMS devices

The density of movable silicon MEMS structures is enhanced by depositing high-density materials in multiple high aspect ratio trenches using atomic layer deposition.A micro electromechanical device having a movable rotor 11 in the silicon wafer 12, and the rotor has one or more high-density regions 17.One or more high density regions in the rotor include at least one high density material having a higher density than silicon.One or more high density regions are formed in the silicon wafer by filling at least one high density material into one or more filling grooves of the rotor.One or more filling grooves have at least 10 depth / width aspect ratios, and one or more filling grooves are filled by depositing high density materials in the filling grooves in an atomic layer deposition (ALD) process.Diagram