Piezo Electrode Patterns

The solid electrode pattern is the most common or “standard” electrode pattern that is applied to piezoelectric ceramics manufactured by American Piezo. APC’s solid electrode pattern is applied using a silk screening process to the positive and negative surfaces of the ceramic. The entire ceramic is then polarized to give it its piezoelectric properties. The solid electrode pattern is the most cost effective pattern to be manufactured and therefore results in a less expensive piezoelectric ceramic for the end customer.

Another common electrode pattern applies to piezoelectric ceramics is the wrap-around electrode pattern. This pattern is sometimes referred to as “WFB” or “with feedback”. The wrap-around electrode pattern is typically applied to “thinner” piezo ceramics, where the thickness is 2.00 mm or less. The un-electroded band on the electrode pattern must be as wide as the part is thick making this pattern impractical for use on very thick parts of parts with a very small electrode surface area. Due to variations in wrap-around electrode pattern placement and dimensions, APC will often request a drawing or sketch of the desired electrode pattern from the customer. The wrap-around electrode pattern is typically used when a customer desires to connect electrical leads to the same surface of the ceramic. This may be necessary if the customer desires to then bond the opposite surface of the ceramic against a flat surface.

The side tab electrode pattern can be used if the thickness of a ceramic is too great, relative to the electrode surface area, for the wrap-around electrode pattern. The side tap electrode pattern allows for an alternate connection to the front face of the piezoelectric ceramic when a wrap-around electrode pattern cannot be applied.

The insulation band electrode pattern is designed to have a reduced electrode with electrical insulation. The isolation band electrode pattern is used to isolate an electrical input from a casing or housing. The pattern can be applied to both the positive and negative surfaces of a ceramic. The isolation band electrode pattern can also be used to change the capacitance of a piezoelectric ceramic.

With the bull’s-eye electrode pattern, the bottom surface, the sides, and a portion of the top surface are electroded. The top surface of the ceramic has a reduced electrode pattern with an insulation band separating the positive and negative electrodes. The insulation band on the bull’s-eye needs to be as thick as the ceramic. The bull’s-eye pattern is typically used in nebulizer and knock sensor applications.