US 12,272,856 B2
Multi-layer signal transmission line including a void of specified dimensions and method for manufacture
Yushi Soeta, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Oct. 24, 2022, as Appl. No. 17/971,671.
Application 17/971,671 is a continuation of application No. PCT/JP2021/015484, filed on Apr. 14, 2021.
Claims priority of application No. 2020-083980 (JP), filed on May 12, 2020.
Prior Publication US 2023/0038684 A1, Feb. 9, 2023
Int. Cl. H01P 3/08 (2006.01)
CPC H01P 3/082 (2013.01) [H01P 3/08 (2013.01); H01P 3/085 (2013.01); H01P 3/088 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A signal transmission line comprising:
a multilayer body including a structure in which a plurality of insulating resin layers are laminated in a multilayer body up-down direction;
a first signal conductor layer in the multilayer body, the first signal conductor layer extending in a multilayer body front-back direction;
a first ground conductor layer on the multilayer body, the first ground conductor layer being positioned above the first signal conductor layer with respect to the multilayer body up-down direction to overlap with the first signal conductor layer in a view in a multilayer body downward direction;
a second ground conductor layer on the multilayer body, the second ground conductor layer being positioned below the first signal conductor layer with respect to the multilayer body up-down direction to overlap with the first signal conductor layer in the view in the multilayer body downward direction;
a first interlayer connection conductor in the multilayer body and positioned at a left of the first signal conductor layer with respect to a multilayer body left-right direction, the first interlayer connection conductor making an electrical connection between the first ground conductor layer and the second ground conductor layer; and
a second interlayer connection conductor in the multilayer body and positioned at a right of the first signal conductor layer with respect to the multilayer body left-right direction, the second interlayer connection conductor making an electrical connection between the first ground conductor layer and the second ground conductor layer; wherein a conductor non-formed portion where no conductor layer exists is provided in the first ground conductor layer;
the multilayer body includes a void where no insulating resin exists;
a dimension of the void in the multilayer body left-right direction is less than a dimension of the multilayer body in the multilayer body left-right direction;
at least a portion of the conductor non-formed portion is provided in a first area positioned at a right of the first interlayer connection conductor with respect to the multilayer body left-right direction and at a left of the second interlayer connection conductor with respect to the multilayer body left-right direction in the view in the multilayer body downward direction;
at least a portion of the void overlaps with the conductor non-formed portion in the first area in the view in the multilayer body downward direction and is provided above the first signal conductor layer with respect to the multilayer body up-down direction and below the first ground conductor layer with respect to the multilayer body up-down direction; and
a third interlayer connection conductor that makes an electrical connection between the first ground conductor layer and the second ground conductor layer is not provided in the first area.