Abstract: A drill achieves a long tool life while improving a property for discharging chips. The drill includes: a columnar body which is rotated about an axis; a plurality of cutting edges each being formed at a tip end portion of the body; and a plurality of thinning edges each being formed in conjunction with the cutting edge nearer the axis by providing thinnings at the tip end portion of the body. At least one of the plurality of thinning edges is provided with a concave portion that is formed by cutting the thinning edge to be recessed in a semicircular shape toward the rear side in the rotational direction, and a center of the semicircular-shaped concave portion is provided on a line extended from the tip end portion of the thinning edge when viewed from a tip end direction of the body.

Abstract: A semiconductor device includes a plurality of semiconductor integrated circuits bonded to a structure body in which a fibrous body is impregnated with an organic resin. The plurality of semiconductor integrated circuits are provided at openings formed in the structure body and each include a photoelectric conversion element, a light-transmitting substrate which has stepped sides and in which the width of the projected section on a first surface side is smaller than that of a second surface, a semiconductor integrated circuit portion provided on the second surface of the light-transmitting substrate, and a chromatic color light-transmitting resin layer which covers the first surface and part of side surfaces of the light-transmitting substrate. The plurality of semiconductor integrated circuits include the chromatic color light-transmitting resin layers of different colors.

Abstract: An object is to reduce the breakage of appearance such as a crack, a split and a chip by external stress of a semiconductor device. Another object is that manufacturing yield of a thin semiconductor device increases. The semiconductor device includes a plurality of semiconductor integrated circuits mounted on the interposer. Each of the plurality of semiconductor integrated circuits includes a light transmitting substrate which have a step on the side surface and in which the width of one section of the light transmitting substrate is narrower than that of the other section of the light transmitting substrate when the light transmitting substrate is divided at a plane including the step, a semiconductor element layer including a photoelectric conversion element provided on one surface of the light transmitting substrate, and a chromatic color light transmitting resin layer which covers the other surface of the light transmitting substrate and a part of the side surface.