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US 5,846,892 AGranted
Ceramic dielectrics and methods for forming the same
AssigneeSumitomo Metal Industries, Ltd.
InventorTakahiro Takada
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AssigneeSumitomo Metal Industries, Ltd.
InventorTakahiro Takada
Estimating the term…
The present invention relates to a ceramic dielectrics. It is difficult to downsize a MgTiO.sub.2 -base ceramic composition conventionally used, having an insufficiently high relative dielectric constant (.di-elect cons..sub.r), less than 20, while a CaTiO.sub.3 -base ceramic composition, having a small value of Q, is not suitable for electronic devices processing a signal in the high-frequency-bandwidth. Moreover, it is difficult to control the temperature coefficient of resonant frequency of these conventional ceramic compositions. In the present invention, a ceramic dielectrics having a composition represented by xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Ln.sup.1.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z (wherein Ln.sup.1 and Ln.sup.2 are lanthanoids, and w, x, y, and z are values in the ranges of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.05.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively) contributes to solving the above problems. The ceramic dielectrics according to the present invention can be used as a material for a resonator processing a signal in the microwave-bandwidth, a filter, a capacitor or the like.
A ceramic dielectric consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Ln.sup.1.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids and w, x, y, and z are values in the range of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.1.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively.
A ceramic dielectric consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Ln.sup.1.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids and w, x, y, and z are values in the range of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.05.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively and ZnO and/or MnO as additives in the range of a to 1 mol of the principal component, where the value of a is 0<a.ltoreq.0.2.
A ceramic dielectric consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Nd.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.2 is a lanthanoid and w, x, y, and z are values in the range of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.1.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively.
A ceramic dielectric consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Nd.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.2 is a lanthanoid and w, x, y, and z are values in the range of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.05.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively and ZnO and/or MnO as additives in the range of a to 1 mol of the principal component, where the value of a is 0<a.ltoreq.0.2.
A method for forming ceramic dielectrics, comprising the steps of preparing raw materials selected from compounds each of which contains one of Mg, Ca, Ti, Ln.sup.1, and Ln.sup.2, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids in such ceramic dielectrics after being sintered consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Ln.sup.1.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids and w, x, y, and z are values in the ranges of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.01.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively, mixing, pressing, and then sintering the same at a temperature of 1200.degree.-1600.degree. C. in air or an oxygen atmosphere.
A method for forming ceramic dielectrics, comprising the steps of preparing raw materials selected from compounds each of which contains one of Mg, Ca, Ti, Ln.sup.1, and Ln.sup.2, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids, and a powder as sintering agents selected from compounds containing Zn and/or Mn in such ceramic dielectrics after being sintered consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Ln.sup.1.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids and w, x, y, and z are values in the ranges of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.05.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively, and ZnO and/or MnO as additives in the range of a to 1 mol of the principal component, where the value of a is 0<a.ltoreq.0.2, mixing, pressing, and then sintering the same at a temperature of 1200.degree.-1600.degree. C. in air or an oxygen atmosphere.
A method for forming ceramic dielectrics, comprising the steps of preparing raw materials selected from compounds each of which contains one of Mg, Ca, Ti, Ln.sup.1, and Ln.sup.2, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids, and a powder as sintering agents selected from compounds containing Zn and/or Mn in such ceramic dielectrics after being sintered consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Ln.sup.1.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids and w, x, y, and z are values in the ranges of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.1.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively, and ZnO and/or MnO as additives in the range of a to 1 mol of the principal component, where the value of a is 021 a.ltoreq.0.2, is formed after being sintered, mixing, pressing, and then sintering the same at a temperature of 1200.degree.-1600.degree. C. in air or an oxygen atmosphere.
A method for forming ceramic dielectrics, comprising the steps of preparing raw materials selected from compounds each of which contains one of Mg, Ca, Ti Ln.sup.1, and Ln.sup.2, wherein Ln.sup.1 and Ln.sup.2 are lanthanoids, and a powder as sintering agents selected from compounds containing Zn and/or Mn in such ceramic dielectrics after being sintered consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Ln.sup.1.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z , wherein Ln.sup.1 and Ln.sup.2 are lanthanoids and w, x, y, and z are values in the ranges of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.05.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively, and ZnO and/or MnO as additives in the range of a to 1 mol of the principal component, where the value of a is 0<a.ltoreq.0.2, is formed after being sintered, mixing, calcining, granulating, pressing, and then sintering the same at a temperature of 1200.degree.-1600.degree. C. in air or an oxygen atmosphere.
A method for forming ceramic dielectrics, comprising the steps of preparing raw materials selected from compounds each of which contains one of Mg, Ca, Ti, Nd, and Ln.sup.2, wherein Ln.sup.2 is a lanthanoid, and a powder as sintering agents selected from compounds containing Zn and/or Mn in such ceramic dielectrics after being sintered consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Nd.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.2 is a lanthanoid and w, x, y, and z are values in the ranges of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.1.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively, and ZnO and/or MnO as additives in the range of a to 1 mol of the principal component, where the value of a is 0<a.ltoreq.0.2, mixing, calcining, granulating, pressing, and then sintering the same at a temperature of 1200.degree.-1600.degree. C. in air or an oxygen atmosphere.
A method for forming ceramic dielectrics, comprising the steps of preparing raw materials selected from compounds each of which contains one of Mg, Ca, Ti, Nd, and Ln.sup.2, wherein Ln.sup.2 is a lanthanoid, and a powder as sintering agents selected from compounds containing Zn and/or Mn in such ceramic dielectrics after being sintered consisting essentially of xMgTiO.sub.3.(1-x)CaTiO.sub.3.y(Nd.sub.1-w Ln.sup.2.sub.w).sub.2 Ti.sub.2z O.sub.3+4z, wherein Ln.sup.2 is a lanthanoid and w, x, y, and z are values in the ranges of 0.ltoreq.w<1, 0.20.ltoreq.x.ltoreq.0.80, 0.05.ltoreq.y.ltoreq.5.0, and 0.25.ltoreq.z.ltoreq.1.5, respectively, and ZnO and/or MnO as additives in the range of a to 1 mol of the principal component, where the value of a is 0<a.ltoreq.0.2, is formed after being sintered, mixing, calcining, granulating, pressing, and then sintering the same at a temperature of 1200.degree.-1600.degree. C. in air or an oxygen atmosphere.
Dependencies are inferred from the claim text.