| 摘要 |
<p>PURPOSE:To enable write of a chip code for every one chip also in an entire reticle process by forming a plurality of fuses on a chip as a chip code when write of a chip code for showing each hysteresis is performed for each chip and by carrying out binary display by cutting a specified fuse. CONSTITUTION:At present, a laser fuse ROM is mounted on an IC memory using a redundant circuit, and a fuse is cut by a laser trimming device in a test process to make a good circuit by replacing a defective circuit with the redundant circuit. If write of a chip code is carried out in the laser trimming process, write of a chip code is possible for every one chip in any way. A chip code 6 carries out binary display by a fuse cut by scanning a laser passing through a center of the fuse and a fuse which is not cut. The fuse of the chip code has the same configuration, the same layer structure and the same material as a fuse ROM formed inside the chip. Since it is not necessary to connect the fuses electrically, they can be put outside an Al ring 3.</p> |
