Abstract:
A multilayer printed wiring board having a field via structure and having an excellent connection reliability between via holes. A lower-layer via hole (50) having a flat surface is formed by filling up an opening (42) provided in a lower interlayer resin insulating layer (40) with a plating metal (48), and an upper-layer via hole (70) is formed by providing an opening (62) in an upper interlayer resin insulating layer (60) of the via hole (50). Since the lower-layer via hole (50) has a flat surface and no resin is left on the surface, the connection reliability between the via hole (50) and the upper-layer via hole (70) is secured. In addition, since the surface of the via hole (50) is flat, the surface smoothness of the multilayer printed wiring board is not marred even when the upper-layer via hole (70) is formed on the via hole (50).
Abstract:
A method for depositing a solder layer (280) or solder bump on a sloped surface (220). The method includes etching a sloped surface on a planar semiconductor substrate (200), depositing a solder-wettable layer (230) on the sloped surface, masking the wettabler layer with a coating layer (240) to control the position of the solder deposition, and using an organic film (250) to prevent the solder from being deposited at regions not above either the wettable layer or the coating layer. Also, a semiconductor device structure on which a solder layer or solder bump is formed exclusively on a sloped surface.
Abstract:
The present invention intends to provide a terminal structure strong in the peel strength of a land portion and a ball. In a terminal structure according to the invention, a land portion (2) includes a terminal portion for soldering a ball (7) ; a support portion (4) disposed in the neighborhood of an outer periphery portion of the terminal portion; and a link portion (5) for linking the terminal portion and the support portion; and wherein on a base material, with an entirety of the terminal portion including an edge portion located in the outer periphery portion of the terminal portion exposed, an insulating layer (6) is disposed so as to cover the support portion; and with a solder straddled a surface and an edge portion of the terminal portion, the ball is soldered to the terminal portion. Accordingly, the terminal structure that is large in the peel strength of the ball from the terminal portion and of the terminal portion from the base material can be obtained.
Abstract:
A multilayer printed wiring board having a field via structure and having an excellent connection reliability between via holes. A lower-layer via hole (50) having a flat surface is formed by filling up an opening (42) provided in a lower interlayer resin insulating layer (40) with a plating metal (48), and an upper-layer via hole (70) is formed by providing an opening (62) in an upper interlayer resin insulating layer (60) of the via hole (50). Since the lower-layer via hole (50) has a flat surface and no resin is left on the surface, the connection reliability between the via hole (50) and the upper-layer via hole (70) is secured. In addition, since the surface of the via hole (50) is flat, the surface smoothness of the multilayer printed wiring board is not marred even when the upper-layer via hole (70) is formed on the via hole (50).
Abstract:
A thick film circuit with a perimeter anchored thick film pad is provided. The thick film circuit includes a base substrate, a thick film bonding pad, and a solder mask layer. The thick film bonding pad is formed on the surface of the base substrate. The solder mask layer is also formed on the surface of the base substrate, and overlaps a portion of the thick film bonding pad in order to improve adhesion between the thick film bonding pad and the base substrate.
Abstract:
The package-side land 3a of a semiconductor package P1 is wholly exposed into the opening 5a of a solder resist layer 5. The board-side land 12a of the mount board B1 is also wholly exposed into the opening 13a of a solder resist layer 13. When the semiconductor package P1 and the mount board B1 are joined to each other through a soldering layer 14a, the soldering layer 14a is brought into contact to both the lands 3a and 12a while extending to the side wall surfaces thereof so that the joint strength can be enhanced by the increasing contact area and the shape. When the lands 3a and 12a are set to be equal to each other in dimension and shape, the soldering layer 14a is shaped into a pillar having a substantially uniform section, thereby preventing local concentration of stress. To ensure the joint strength based on a conductive material layer and enhance the mount reliability by making fine the terminals on a relay substrate which correspond to the input or output terminals of a semiconductor chip, and making the pitch narrow.
Abstract:
A multilayer printed circuit board comprises a core substrate, multilayer wiring layers formed on the substrate by alternately laminating an interlaminar insulating layer and conductor circuit, and a group of solder pads having solder bumps planarly arranged on an outermost surface of the multilayer wiring layers, in which the solder pads located from first row to fifth row from an outer position of the solder pad group are constructed with flat pads connected to conductor pattern located on the outermost surface and solder bumps formed on the surfaces of the pads, while the solder pad group other than these solder pads are constructed with viaholes connected to flat innerlayer pad group located in an inner layer and solder bumps formed in recess portions of the viaholes, and the solder pads located from first row to fifth row from an outer position of the innerlayer pad group are constructed with flat pads connected to conductor patterns in the same layer as the innerlayer pad group, while the innerlayer pad groups other than the pads are constituted with flat pads connected to a further innerlayer flat pad group located inward the above innerlayer through viaholes.
Abstract:
To prevent that holes (3) of a circuit board not equipped with circuit elements and designed for later equipment are filled by soldering material (5), a small solder resisting strip (6) is printed upon the conductor (2) diametrically transversing said hole (3).