| 摘要 |
PURPOSE:To provide a partial electrode of predetermined shape by etching an AuSi or AuGe alloy electrode using a first solution containing phosphoric acid, nitric acid and fluoric acid and a second solution containing iodine and potassium iodide each once and then etching it with denatured layer exposed with the first solution. CONSTITUTION:An LED having predetermined alloy electrode layer is dipped in the first solution containing phosphoric acid, nitric acid, fluoric acid and water at 5:3:1:1 by volumetric ratio to etch thereby an electrode for predetermined time to thereby selectively etch oxide and alloy layer on the surface of the electrode layer. An electrode layer 2 is etched with second solution containing 25g iodine, 50g potassium iodide and 500cc water. When the electrode layer is again etched with the first solution with the electrode 2 as a mask, the modified layer 3 having the same composition as the alloy layer is etched. Since the first solution does not almost etch the LED substrate 1, the exposed surface does not become rough but provides extremely preferable light reflecting rate. |
