Printed wiring board having a blind via
AssigneeIbiden Co., Ltd.
InventorAkihiro Demura
Life of this patent
Estimating the term…
Abstract
Disclosed is a printed wiring board 1 with a through hole 5 in which a hollow portion 7 wider than both an upper opening 5A and a lower opening 5A is formed, and a solder resist film 9 is formed at the hollow portion 7 so as to firmly adhere to an inner wall of the through hole 5. Thereby, it can prevent the solder resist film 9 from being dropped out from the through hole 5 and electrical check of circuit patterns on the printed wiring board 1 can be efficiently conducted while directly setting a checker pin 13 of a checker into the through hole 5.
Claims19
A printed wiring board having a board, a penetration hole formed in the board in which a conductive layer is formed on an inner wall of the penetration hole and on both an upper and a lower peripheries of the penetration hole to form a through hole, the printed wiring board comprising:
- a film, mainly composed of photosensitive resin, located in the through hole and adhered only at a substantially central position of an inner wall in the through hole, so that the film blinds the through hole.
Dependencies are inferred from the claim text.