LiNbO3 on AlN bonded wafers are composite substrates used for the growth of thin films, such as for acoustic and electro-optic applications. The substrate consists of a lithium niobate (LiNbO3) layer that is bonded to an aluminum nitride (AlN) substrate. The LiNbO3 layer provides the necessary properties for the thin film growth, while the AlN substrate provides mechanical support and thermal stability. The AlN substrate also acts as a buffer layer to prevent the propagation of dislocations from the substrate to the thin film. LiNbO3 on AlN bonded wafers are commonly used in the production of surface acoustic wave (SAW) devices and bulk acoustic wave (BAW) filters.