Abstract: Low loss piezoelectric ceramic compositions cofirable with silver at a reduced sintering temperature and methods for producing the such compositions are provided. The compositions are binary piezoelectric ceramic compositions having a first component which is characterized by about 95.0 to about 99.5 weight percent of a system represented by a general formula Pb(ZrxTi1−x)O3+y wt % MnO2 in which x and y represent weight percentages and wherein x is within a range from 0.0 to about 1.0, and y is within a range from about 0.1 to about 1.0. The compositions also have 0.5 to 5.0 wt % of a second component represented by the general formula w wt % Bi2O3−z wt % CdO in which w and z represent weight percentages and wherein w is within a range from about 0.1 to about 1.0, and z is within a range from about 0.1 to about 2.0. The piezoelectric ceramic compositions are non-reactive with a silver electrode layer when cofired therewith at sintering temperatures of about 900° C.

Abstract: An array (100) of voltage variable capacitors (110) is provided in which voltage variable capacitors (110) are fabricated with piezoelectric displacement devices (150). Voltage variable capacitors (110) have first plates (120) which are coupled to displacement devices (150). First plates (120) are dielectrically coupled to second plates (130). Displacement device (150) has a stack of metallic layers (154), voltage variable material blocks (152), and voltage supply terminals (170) and (180). Voltage differences are established across voltage variable material blocks (152) using voltage supply terminals (170) and (180). A voltage difference causes a voltage variable material layer to change thickness, and this causes first plate (120) to move relative to second plate (130). Voltage variable material is selected from a group of piezoelectric ceramics, which can include lead-titanate (PbTiO.sub.3), lead-zirconate (PbZrO.sub.3), barium-titanate (BaTiO.sub.3), and lead-zirconate-titanate (PbZr.sub.x Ti.sub.1-x O.

Abstract: A low loss piezoelectric ceramic composition cofirable with silver at a reduced sintering temperature and a process for producing the same is provided. The composition is a binary piezoelectric ceramic composition consisting of a main composition which is characterized by 95.0 to 99.5 weight percent of a system represented by a general formula Pb(Zr.sub.x Ti.sub.1-x)O.sub.3 +yMnO.sub.2 in which 0.ltoreq.x.ltoreq.1.0 and 0.1.ltoreq.y.ltoreq.1.0 wt. % The composition also contains 0.5 to 5.0 weight percent of an additive represented by a general formula wB.sub.2 O.sub.3 -xBi.sub.2 O.sub.3 -yMeO-zCuO wherein w,x,y, and z are weight percentages of the respective components and w+x+y+z=1. In the composition, Me is one of the metals selected from a group consisting of Ca, Sr, Ba, Zn, and 0.01.ltoreq.w.ltoreq.0.15, 0.ltoreq.x.ltoreq.0.80, 0.ltoreq.y.ltoreq.0.60 and 0.ltoreq.z.ltoreq.0.55.