Circuit module and method for manufacturing the same

A method for manufacturing a circuit module including a substrate on one main surface of which a first electrode and a second electrode are provided, a first electronic component, and a first resin layer,

• the first electrode including a first electrode base body, and a first plating film,
• the second electrode including a second electrode base body, a metal column which is a sintered body of metal powder, a second plating film, and a covering portion,
• the method for manufacturing a circuit module, comprising:
• a first step of preparing or producing
• first constraining layer green sheets each including a through-hole filled with a conductor paste containing the metal powder which serves as part of the metal column after sintering,
• second constraining layer green sheets,
• a first insulator green sheet to which a conductor paste which serves as the first electrode base body after sintering, a conductor paste which serves as the second electrode base body after sintering, and a conductor paste which serves as a constituent element of an electronic circuit after sintering are applied, and
• second insulator green sheets to each of which a conductor paste which serves as a constituent element of the electronic circuit after sintering is applied;
• a second step of producing a multilayer body by stacking and pressure-bonding
• at least one of the first constraining layer green sheets,
• at least one of the second constraining layer green sheets,
• the first insulator green sheet, and
• at least one of the second insulator green sheets,
• in a state that positioning is performed such that a first constraining layer is present on the one main surface and a second constraining layer is present on another main surface of the substrate after sintering, and the metal column is directly connected onto the second electrode base body;
• a third step of producing a sintered body, by firing the multilayer body, in which the substrate, the first constraining layer present on the one main surface of the substrate, and the second constraining layer present on the other main surface of the substrate are included, and the metal column formed by the metal powder being sintered is directly connected onto the second electrode base body;
• a fourth step of removing the first constraining layer and the second constraining layer;
• a fifth step of simultaneously forming the first plating film at least partially covering an outer surface of the first electrode base body and the second plating film at least partially covering an outer surface of a connection body of the second electrode base body and the metal column;
• a sixth step of connecting the first electronic component to the first electrode;
• a seventh step of providing the first resin layer on the one main surface of the substrate such that the first electronic component and the connection body after plating are entirely covered;
• an eighth step of performing polishing process on the first electronic component and the first resin layer from a surface side positioned on an opposite side from a surface of the first electronic component on a side of the first electrode, such that a thickness of the first electronic component is reduced in comparison with a state before being connected to the first electrode, and an outer surface which is a polished cross section of the first resin layer parallel to the one main surface of the substrate, a polished cross section of the first electronic component, and a polished cross section of the connection body are flush with one another;
• a ninth step of etching the polished cross section of the connection body such that a cross section being exposed of the connection body is positioned in an inner side portion relative to the outer surface of the first resin layer parallel to the one main surface of the substrate;
• and
• a tenth step of forming the covering portion whose one main surface is connected onto the cross section of the connection body exposed after the etching and another main surface is positioned in an outer side portion relative to the outer surface of the first resin layer parallel to the one main surface of the substrate.