The invention relates to a manufacturing process of a pixel array of a thermal pattern sensor comprising the steps of: providing a substrate; depositing a first layer of electrically conductive material, including depositing electrically conductive tracks, depositing of connector pins and depositing a ground strip; depositing of second layer of pyroelectric material covering the tracks and leaving at least part of the connector pins free; depositing of third layer of electrically conductive material; depositing of fourth layer of dielectric material in contact with the third layer; depositing of a fifth layer including electrically conductive heating tracks; depositing of a sixth protective layer, wherein the step of depositing the second and/or third and/or fourth and/or sixth layer is carried out by slot-die coating.