Error correcting codes have been proposed to be used in high frequency memory devices to detect errors in signals transmitted between a memory controller and a memory device. In addition to the foregoing, other method aspects are described in the claims, drawings, and text forming a part of the present disclosure. After a first contact opening is formed in the first insulation film in the wiring region, a first plug is formed by filling a conductive material in the first contact opening. The composition amounts of indium, gallium, and zinc fall within a composition range satisfying the following formula: In<0. Thus, the display device may effectively convert the wavelength of the light emitted from the light source to realize improved brightness and color impression. The apparatus comprises a hand tool with a blade supporting top bar linked to a bottom bar.