Printed wiring board
AssigneeIbiden Co., Ltd.
InventorSusumu Kagohashi
Life of this patent
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Abstract
A printed wiring board includes a first conductor layer, a resin insulating layer formed on the first conductor layer, a second conductor layer formed on a surface of the resin insulating layer, and a via conductor formed in an opening formed in the resin insulating layer such that the via conductor is connecting the first conductor layer and the second conductor layer. The via conductor is formed such that the via conductor includes a seed layer covering an inner wall surface of the resin insulating layer inside of the opening and an electrolytic plating layer formed on the seed layer such that the seed layer has a plurality of columnar parts grown in columnar shapes.
Claims20
A printed wiring board, comprising:
- a first conductor layer;
- a resin insulating layer formed on the first conductor layer;
- a second conductor layer formed on a surface of the resin insulating layer;
- and
- a via conductor formed in an opening formed in the resin insulating layer such that the via conductor is connecting the first conductor layer and the second conductor layer,
- wherein the resin insulating layer has an inner wall surface in the opening such that the inner wall surface has a plurality of steps having a step difference in a range of 3.0 μm or less, the second conductor layer and the via conductor include a seed layer and an electrolytic plating layer formed on the seed layer such that the seed layer is covering the inner wall surface of the resin insulating layer in the opening and has a first smooth portion and a second smooth portion electrically connected to the first smooth portion and that a part of the first smooth portion is formed on the second smooth portion, and the seed layer of the via conductor is formed such that a leading end of the first smooth portion is formed on and overlapping a trailing end of the second smooth portion.
Dependencies are inferred from the claim text.