Murata Manufacturing Co., Ltd.

Yusuke Otsuka

Kazuo Kishida

Yuichi Iida

Takahiro Takada

A multilayer ceramic substrate includes a ceramic laminated body including a plurality of ceramic layers stacked on each other, a resistor, and a resistor connecting conductor with a portion overlapping the resistor and an overcoat layer that covers the resistor located on a principal surface of the ceramic laminated body. An overcoat layer is made relatively thick during firing, thereby making cracks less likely to be caused, and after the firing step, the thickness of the overcoat layer is reduced by physically scraping down the surface of the overcoat layer, thereby reducing the trimming time. In the overcoat layer, a region that covers a portion in which a resistor overlaps a resistor connecting conductor is thicker than a region that covers the other portion.

Multilayer ceramic substrate and method for producing the same

A high-quality resistor pattern and conductor pattern is formed on an external surface of a multilayer ceramic substrate by an ink jet method. A composite sheet including a first ceramic green layer and a shrinkage-retardant layer is formed, and a resistor pattern and a conductor pattern are formed on the first ceramic green layer of the composite sheet by an ink jet method. Subsequently, a plurality of second ceramic green layers are stacked with the composite sheet such that the shrinkage-retardant layer of the composite sheet defines an outermost layer, thus forming a multilayer composite including an unfired multilayer ceramic substrate and the shrinkage-retardant layer. Then, the multilayer composite is fired, and the shrinkage-retardant layer is removed to obtain a sintered multilayer ceramic substrate.

Method for manufacturing multilayer ceramic substrate and composite sheet

A laminate type ceramic electronic component includes a thick film resistor and an overcoat layer so as to prevent defects such as delamination from being caused and to prevent the thick film resistor from being cracked after laser trimming, even when a method is adopted in which an unfired composite laminate is subjected to firing in such a way that an unfired ceramic laminate, an unfired thick film resistor, and an unfired overcoat layer are each integrally sintered. The unfired overcoat layer includes a glass ceramic material containing a ceramic and glass having substantially the same constituents and compositional ratio as those of the glass contained in the unfired ceramic layer. The respective glass ceramic materials constituting the unfired ceramic layer and the unfired overcoat layer are adjusted so that the ratio of a crystalline phase with a smaller coefficient of thermal expansion than the coefficient of thermal expansion of the fired ceramic layer is higher in the overcoat layer than in the ceramic layer.

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Nagaokakyo, Japan

Yusuke Otsuka