Patent ID: 7687015

Claim:
A method for producing a laminated dielectric having a low dielectric constant layer and a high dielectric constant layer alternately laminated in an odd number of layers in total so that a low dielectric constant layer constitutes the outermost layer, which comprises alternately laminating a high dielectric constant raw material layer containing a high dielectric constant glass ceramic composition, to form a high dielectric constant layer having a relative dielectric constant of from 16 to 30 at a frequency of from 1 GHz to 25 GHz, when fired, and a low dielectric constant raw material layer containing a low dielectric constant glass ceramic composition, to form a low dielectric constant layer having a relative dielectric constant of at least 5 at the above frequency, which is smaller by at least 3 than the relative dielectric constant of a high dielectric constant layer adjacent thereto, when fired, in an odd number of layers in total so that a low dielectric constant raw material layer constitutes the outermost layer, followed by firing, wherein: the high dielectric constant glass ceramic composition consists essentially of, as represented by mass percentage, from 30 to 70% of a ceramic powder and from 30 to 70% of a glass powder containing SiO 2 and Al 2 O 3 in an amount of SiO 2 +Al 2 O 3 being from 25 to 50 mol % and further containing at least one of B 2 O 3 , BaO and ZnO and not containing lead and alkali metals, and is one which precipitates crystals when fired at a temperature of from 850 to 900° C.; the low dielectric constant glass ceramic composition consists essentially of, as represented by mass percentage, from 10 to 70% of a ceramic powder and from 30 to 90% of a glass powder containing SiO 2 and Al 2 O 3 in an amount of SiO 2 +Al 2 O 3 being at least 34 mol % and not containing lead and alkali metals, and is one which precipitates crystals when fired at a temperature of from 850 to 900° C.; the difference obtained by subtracting from the amount of SiO 2 +Al 2 O 3 in the glass powder in the low dielectric constant glass ceramic composition of the low dielectric constant raw material layer the amount of SiO 2 +Al 2 O 3 in the glass powder in the high dielectric constant glass ceramic composition of the high dielectric constant raw material layer adjacent to the low dielectric constant raw material layer, is at least 9 mol %; and the difference obtained by subtracting from the amount of B 2 O 3 +BaO+ZnO in the glass powder in the high dielectric constant glass ceramic composition of the high dielectric constant raw material layer the amount of B 2 O 3 +BaO+ZnO in the glass powder in the low dielectric constant glass ceramic composition of the low dielectric constant raw material layer adjacent to the high dielectric constant raw material layer, is at least 30 mol %.