| 摘要 |
<p>PURPOSE:To obtain the title ink which, when applied to a semiconductor chip of poor electrical characteristics, improves the easiness of confirmation of an ultraviolet erasing work of e.g., an EPROM by adding a substance which discolors when irradiated with ultraviolet rays to the ink. CONSTITUTION:A substance (B) which discolors when irradiated with ultraviolet rays in added to an ink (A) to obtain an ink for bad marking, which is sensitive only to ultraviolet rays except ordinary ultraviolets rays such as those in sunlight or from a fluorescent lamp and can be fixed once it discolors. Said ink is applied to a semiconductor chip which proved to have poor electrical characteristics when subjected to an electrical test of a semiconductor wafer to facilitate the confirmation of an ultraviolet erasing work of, e.g., an EPROM.</p> |
