Piezoelectric component

A method of making a piezoelectric component, the method comprising:

• producing a plurality of green sheets, each green sheet comprising unsintered ceramic powder;
• joining the green sheets together with electrode layers;
• and
• sintering the green sheets and the electrode layers to form a stack of piezoelectric layers arranged one above another in a stack and first and second electrode layers arranged between the piezoelectric layers;
• wherein the stack has a first piezoelectric layer having a first electric coercive field strength and, directly adjacent thereto, a second piezoelectric layer having a second electric coercive field strength different than the first electric coercive field strength;
• wherein the first piezoelectric layer and the second piezoelectric layer comprise different ceramic materials, different dopants, different dopant concentrations, different particle sizes of starting materials, different layer thicknesses or a combination thereof;
• wherein the first and second piezoelectric layers comprise ceramic materials produced from starting powders having different particle sizes;
• wherein the particle size of the starting powders is greater than or equal to 0.3 μm and less than or equal to 2.0 μm;
• and
• wherein the difference in the particle sizes of the starting powders is greater than or equal to 0.1 μm and less than or equal to 1.5 μm.

A piezoelectric component comprising:

• a stack of piezoelectric layers arranged one above another;
• and
• first and second electrode layers arranged between the piezoelectric layers;
• wherein the stack has a first piezoelectric layer having a first electric coercive field strength and, directly adjacent thereto, a second piezoelectric layer having a second electric coercive field strength different than the first electric coercive field strength;
• wherein the first piezoelectric layer and the second piezoelectric layer comprise different ceramic materials, different dopants, different dopant concentrations, different particle sizes of starting materials, different layer thicknesses or a combination thereof;
• wherein the first and second piezoelectric layers comprise ceramic materials produced from starting powders having different particle sizes;
• wherein the particle size of the starting powders is greater than or equal to 0.3 μm and less than or equal to 2.0 μm;
• wherein the difference in the particle sizes of the starting powders is greater than or equal to 0.1 μm and less than or equal to 1.5 μm;
• wherein the first and second piezoelectric layers comprise a ceramic material formed from a plurality of constituents having respective concentrations;
• wherein the first and second piezoelectric layers differ in a concentration of at least one constituent;
• wherein the first and second piezoelectric layers comprise a ceramic material having the same constituents;
• wherein the ceramic material has, depending on a concentration of at least one first constituent, a morphotropic phase boundary lying between a first structure and a second structure of the ceramic material;
• and
• wherein the concentration of a first constituent of the ceramic material in the first and second piezoelectric layers is in each case chosen in such a way that the first piezoelectric layer comprises the ceramic material having the first structure and the second piezoelectric layer comprises the ceramic material having the second structure.