A power semiconductor module includes a power semiconductor element having a first electrode, a second electrode, and a control electrode. The power semiconductor element is configured to selectively control a conductivity state between the first electrode and the second electrode. The power semiconductor module further includes a first power line electrically connected to the first electrode, a second power line electrically connected to the second electrode, a first control line electrically connected to the control electrode, a second control line electrically connected to the second electrode, and a heat sink having a front surface on which the power semiconductor element is formed. The heat sink includes a shielding layer. The first control line and the second control line extend through the heat sink.

A header for a semiconductor package, includes an eyelet having a through hole penetrating the eyelet from an upper surface to a lower surface of the eyelet, a first lead inserted inside the through hole, and an insulating substrate disposed on the upper surface of the eyelet, and provided with a first through hole at a position overlapping one end of the first lead in a plan view. The insulating substrate has a thermal conductivity lower than a thermal conductivity of the first lead. A first conductive layer is formed on an inner wall defining the first through hole, and the first conductive layer extends to an upper surface of the insulating substrate. The one end of the first lead is electrically connected to the first conductive layer, and a space is provided above the one end of the first lead inside the first through hole.

According to a manufacturing method of the present invention, it is possible to manufacture a busbar assembly in an efficient manner, the busbar assembly including busbars disposed in parallel in a common plane and an insulative resin layer including a gap filling portion filled into a gap between the adjacent busbars and a bottom-surface-side laminated portion extending integrally from the gap filling portion and arranged on bottom surfaces of the busbars, a top surface of the busbar being at least partially exposed to form a top-surface-side connection portion, the bottom surface of the busbar including a first bottom surface region which is located at the same position in a thickness direction as a lower end portion of the gap and on which the bottom-surface-side laminated portion is arranged and a second bottom surface region located farther away from the top surface than the first bottom surface region and exposed to the outside to form a bottom-surface-side connection portion.