Wiring circuit board and method of producing the same

Abstract

A wiring circuit board includes an insulating layer having a via penetrating in a thickness direction, a first conductive layer disposed on a one-side surface in the thickness direction of the insulating layer, a second conductive layer disposed on the other-side surface in the thickness direction of the insulating layer, and a conductive portion disposed on an inner peripheral surface of the via and electrically connecting the first and second conductive layers. Length L of 1 μm-10 μm inclusive, is measured by: drawing a segment joining first and second connection points from respectively, the one-side surface to the other-side surface in the thickness direction of the insulating layer and the inner peripheral surface in the cross-sectional view; identifying an outermost position farthest outward from the segment on the inner peripheral surface in the cross-sectional view; and measuring the length as the shortest distance from the segment to the outermost position.