A semiconductor device comprising: a substrate; a semiconductor chip disposed on the substrate; a plurality of electrodes disposed on the substrate separately from one another and arranged so as to surround the semiconductor chip in a plan view; a lid that covers the semiconductor chip, the lid including: a plate-like member comprising an inner portion and a periphery portion that is outer than the inner portion in a plan view, the lid further including: a plurality of protruding members provided separately from one another at the inner portion, the protruding members protruding towards the substrate, a sidewall member disposed along the periphery portion so as to surround the plurality of protruding members in a plan view; and conductive members disposed between the plurality of electrodes and the plurality of protruding members disposed in positions opposed to the plurality of electrodes respectively, the conductive members being joined to the plurality of electrodes and the plurality of protruding members respectively, wherein the plurality of electrodes, the lid and the conductive members are configured to be electrically connected to ground, and wherein the plate-like member, the plurality of protruding members and the sidewall member include the same metal. a substrate; a semiconductor chip disposed on the substrate; a plurality of electrodes disposed on the substrate separately from one another and arranged so as to surround the semiconductor chip in a plan view; a lid that covers the semiconductor chip, the lid including: a plate-like member comprising an inner portion and a periphery portion that is outer than the inner portion in a plan view, the lid further including: a plurality of protruding members provided separately from one another at the inner portion, the protruding members protruding towards the substrate, a sidewall member disposed along the periphery portion so as to surround the plurality of protruding members in a plan view; and conductive members disposed between the plurality of electrodes and the plurality of protruding members disposed in positions opposed to the plurality of electrodes respectively, the conductive members being joined to the plurality of electrodes and the plurality of protruding members respectively, wherein the plurality of electrodes, the lid and the conductive members are configured to be electrically connected to ground, and wherein the plate-like member, the plurality of protruding members and the sidewall member include the same metal. a plate-like member comprising an inner portion and a periphery portion that is outer than the inner portion in a plan view, the lid further including: a plurality of protruding members provided separately from one another at the inner portion, the protruding members protruding towards the substrate, a sidewall member disposed along the periphery portion so as to surround the plurality of protruding members in a plan view; and conductive members disposed between the plurality of electrodes and the plurality of protruding members disposed in positions opposed to the plurality of electrodes respectively, the conductive members being joined to the plurality of electrodes and the plurality of protruding members respectively, a plurality of protruding members provided separately from one another at the inner portion, the protruding members protruding towards the substrate, a sidewall member disposed along the periphery portion so as to surround the plurality of protruding members in a plan view; and conductive members disposed between the plurality of electrodes and the plurality of protruding members disposed in positions opposed to the plurality of electrodes respectively, the conductive members being joined to the plurality of electrodes and the plurality of protruding members respectively, wherein the plurality of electrodes, the lid and the conductive members are configured to be electrically connected to ground, and wherein the plate-like member, the plurality of protruding members and the sidewall member include the same metal.