This paper presents the design and characterization of thermally actuated Al-Si bimetallic membranes. The design was made with the Finite Element Method and was emphasized on optimizing the thickness ratio between the aluminum and silicon layers. The membrane deflection was measured employing the Michelson Interferometer. The experimental process was carried out with square membranes of 5 mm of side length, 10 mm in silicon thickness, and an aluminum thicknesses of 4 and 1 mm. A maximum deflection of 14 mm was obtained for membranes with 4 mm of aluminum thickness, which is consistent with predictions made by numerical calculations.