Patent ID: 8592851

Claim:
An electric circuit device comprising: a board having a mount surface; a plurality of electric circuit components mounted on the board; and an optical semiconductor device mounted on the board, wherein the optical semiconductor device includes a light-emitting element, a lead frame having a cupped concave portion, a pair of electrode terminals connected to the mount surface of the board, and a pair of connecting portions each connecting the concave portion and at least one of the electrode terminals, the concave portion configured to receive the light-emitting element therein, and a sealing resin portion located adjacent a region of the concave portion, the connecting portions extending away from a bottom-most surface of the sealing resin portion and in a direction towards the board, a bottom-most surface of the concave portion being exposed from the bottom-most surface of the sealing resin portion toward the board, wherein a distance between the bottom-most surface of the sealing resin portion and the mount surface is longer than or equal to a distance between the exposed portion of the bottom-most surface of the concave portion to the mount surface, the lead frame is configured in such a manner that the bottom-most surface of the concave portion and the bottom-most surface of the sealing resin portion are spaced from the mount surface of the board and the electrode terminals connected to the mount surface such that an air layer is located between the mount surface of the board and the bottom-most surface of the concave portion of the optical semiconductor device, and the bottom-most surface of the concave portion is in contact with the air layer, wherein the bottom-most surface of the sealing resin portion, completely surrounding the exposed portion of the bottom-most surface of the concave portion in a top view, is entirely inclined with respect to the mount surface to form a convex surface with the exposed portion of the bottom most surface of the concave portion facing the board, the exposed portion of the bottom-most surface of the concave portion located at a position of the convex surface closest to the mount surface with a distance therebetween, and an end of the bottom-most surface of the sealing resin portion is in direct contact with an end of the bottom-most surface of the concave portion, wherein the bottom-most surface of the concave portion has a surface area that is greater than an upper-most surface of the concave portion to which the light emitting element is attached, and wherein, when the optical semiconductor device is operation, the air layer is caused to flow under the bottom-most surface of the concave portion.