Printed wiring board

A printed wiring board comprising:

• a first insulating layer having a first main surface and a second main surface opposite to the first main surface;
• a first wire pattern, a second wire pattern, and a first ground pattern that are disposed on the second main surface and extend along a first direction in a plan view;
• a second ground pattern disposed on the first main surface;
• an adhesive layer disposed on the second main surface so as to cover the first wire pattern, the second wire pattern, and the first ground pattern;
• a second insulating layer disposed on the adhesive layer and having a third main surface facing the adhesive layer and a fourth main surface opposite to the third main surface;
• a third ground pattern disposed on the fourth main surface;
• and
• a first conductor layer and a second conductor layer, wherein
• in a second direction orthogonal to the first direction, the first ground pattern is located between the first wire pattern and the second wire pattern, and spaced apart from the first wire pattern and the second wire pattern,
• in the first insulating layer and the second ground pattern, a plurality of first through-holes passing through the first insulating layer and the second ground pattern in a thickness direction orthogonal to the first direction and the second direction, and overlapping the first ground pattern in a plan view are formed,
• the plurality of first through-holes are spaced apart from each other and arranged to line up along the first direction,
• in the adhesive layer, the second insulating layer, and the third ground pattern, a plurality of second through-holes passing through the adhesive layer, the second insulating layer, and the third ground pattern in the thickness direction, and overlapping the first ground pattern in a plan view are formed,
• the plurality of second through-holes are spaced apart from each other and arranged to line up along the first direction,
• the first conductor layer is disposed on an inner wall surface of each of the plurality of first through-holes, and electrically connected to the first ground pattern and the second ground pattern,
• the second conductor layer is disposed on an innter wall surface of each of the plurality of second through-holes, and electrically connected to the first ground pattern and the third ground pattern, and
• each of the plurality of first through-holes and each of the plurality of second through-holes have a width in the first direction and a width in the second direction, and the width in the first direction is equal to the width in the second direction.