Formation of PZT micro-scale structures using electrohydrodynamic atomization filling of metallic moulds

In our previous work electrohydrodynamic atomization (EHDA) combined with a photolithography polymeric micromoulding technique was used to form PZT ceramic micro-scale structures. The major drawback of this technique was the deformation of the polymeric mould resulting in irregular PZT structures.In order to overcome the above drawback, nickel micromoulds were used in this work to form PZT structures. It was observed that the PZT structures presented more regular features compared with those obtained from polymeric micromoulds. The smallest PZT square sizes and separations achieved were 78 μm and 31 μm, which correspond to the minimum nickel micromould cavity obtainable. The side wall angle was increased by using a release agent to prevent excessive build up of PZT at the edges of the mould cavity. The resulting PZT structures exhibited a relative permittivity of 240, d33,f of 70 pCN−1 and remnant polarisation of 9.3 μC cm−2 at 35 V μm−1.