Alternative temperature compensating materials to amorphous silica in acoustic wave resonators

An acoustic wave device comprising:

• a piezoelectric material;
• and
• a second material disposed on the piezoelectric material and having a temperature coefficient of frequency of a sign opposite a sign of a temperature coefficient of frequency of the piezoelectric material, the second material including one or more of Si1-x-yTixPyO2-zFz (x,y,z<0.1), Si1-x-yGexPyO2-zFz, Si1-x-yBxPyO2-zFz (x=y<0.04), Si1-3xZnxP2xO2-yFy, Si1-xPxO2-yFy, Si1-2yGaxPxO4, Si1-2yGay-xBxPyO4, Si1-2yGay-xBxPyO4-zFz, or TiNb10O29.

An acoustic wave device comprising:

• a piezoelectric material;
• and
• a second material disposed on the piezoelectric material and having a temperature coefficient of frequency of a sign opposite a sign of a temperature coefficient of frequency of the piezoelectric material, the second material including one or more of Si1-xTixO2-yFy, Si1-x-yTixPyO2, Si1-xBxO2-yFy, Si1-x-yBxPyO2, GeO2, GeO2-yFy, Si1-xGexO2, Si1-xGexO2-yFy, Si1-x-yGexPyO2, ZnP2O6, Si1-3xZnxP2xO2, Ge1-3xZnxP2xO2, TeOx, Si1-xTexO2+y, Ge1-xTexO2+y, Si1-3x-yGeyZnxP2xO2, Si1-xPxO2-xNx, Si—O—C, Si1-2yAlxPxO4, or BeF2.