The invention provides technology for
processing an audio directional
loudspeaker film, namely technology for
processing a PZT piezoelectric film. The
processing technology comprises preparation of a PZT solution precursor
monomer and
coating of the PZT film, and mainly comprises the following steps of: selecting
titanium salt,
zircon salt,
lead acetate raw materials and an
organic solvent; mixing a certain amount of
titanium salt and a certain amount of
organic solvent, and heating and uniformly stirring to
form solution A; adding a certain amount of
lead acetate, catalyst and stabilizing agent into the solution A, and heating and uniformly stirring under the action of a condensation and
reflux device to
form solution B; adding a certain amount of
zircon salt into the solution B, and heating and uniformly stirring to
form solution C; filtering the solution C to obtain PZT
sol; adding an additive into the
sol to adjust
viscosity and hydrolyzing degree; dripping the PZT
sol onto an
SI substrate or an Si\SiO2\Si3N4\Pt\Ti structure substrate, and performing sol smoothening and sol throwing to obtain a substrate A; performing low temperature heat treatment on the substrate A to obtain a substrate B;
sintering and annealing the substrate B to obtain substrates C and D; and naturally cooling the substrate D to
room temperature to obtain a single-layer PZT film. The processing technology is mature in technique, the
process equipment is simple, the cost is low, vacuum is not needed, an even film can be prepared on a large-area substrate; meanwhile, the temperature of the heat treatment is low, so the stoichiometric ratio of the film is easily controlled; and the technology can be compatible with the micro electronic technique, and can meet the requirement of an audio directional
loudspeaker on an inorganic piezoelectric film with a crystalline structure to some extent.