| 摘要 |
PURPOSE:To prevent the decrease in lot-number reading accuracy due to noise by etching the surface of a semiconductor wafer, forming a lot-number pattern on a printing area, forming a metal film on the entire surface, and selectively removing the unnecessary part of the metal film on a circuit area and the metal film on the printing area at the same time. CONSTITUTION:A printing area 12 and a circuit area 13 are set on a semiconductor wafer 11. The surface of the printing area is etched, and a lot-number pattern 14 is printed. Then, an insulating film 15, a metal film such as Al and a resist film 17 are sequentially formed on the entire surface. The unnecessary part of the metal film 16 in the circuit area 13 and the resist 17 on the printing area 12 are exposed, developed and removed. Then, with the resist 17 as a mask, the metal film 16 is etched. The metal film 16 at the unnecessary part of the circuit area 13 and on the printing area 12 is selectively removed. The remaining resist 17 is further removed. Then, the same process is repeated, and the circuit pattern is completed. The metal film is not accumulated on the printing area, and mixing of the noise component caused by foreign matter into read-out signals is prevented. |
