Bar code and read-out method thereof

Abstract

Abstract A conventional bar code and a method of reading the same are so adapted that rays are irradiated on the bar code formed on a semiconductor wafer, and that reflected rays from the bar code are read out by a bar code reader to sense the bar code so that a misreading rate is increased by means of reflection of the surface of a wafer and due to the surface profile of the bar code. In contrast, according to a bar code and a method of reading the same in accordance with the present invention, the bar code is formed of a film or the like of aluminum or the like on the semiconductor wafer, and infrared rays are irradiated on the bar code, penetrated infrared rays from the semiconductor wafer being read out by the bar code reader so that a bar code reading may be effectively made without being influenced by reflection of the wafer surface and surface profile with a better S/N ratio and at a lower misreading rate.

Inventors

• 👤 Keiji Hiramatsu

Bibliographic Details