| 摘要 |
PURPOSE:To obtain a mark of semiconductor device not to be vanished at a high speed when the prescribed mark is to be entered on the surface of a package to accommodate a semiconductor element by a method wherein a laser beam is irradiated on the surface selectively to remove a thin layer on the surface indicating the mark. CONSTITUTION:An IC chip is affixed on the ceramic package 1 for IC necessary bonding is performed, and a cover 2 produced by applying a gold plating layer on the surface of copal is covered on the package 1. When the prescribed mark is to be entered on the cover 2, the laser beam 3 supplied from a laser oscillator 4 and a laser deflector 5 is irradiated thereto selectively, the gold plating layer on the surface is made to be evaporated rapidly to make the surface of copal layer of the lower layer to be exposed, and the mark is indicated by utilizing difference of the color tone. When the mark is to be entered on the package 1, the laser beam 3 is irradiated similarly, and grooves are dug on the smooth and falt surface layer to indicate the mark. Or the package may be constituted of two layers having different color tones, and the surface layer only is removed selectively. |
