| 摘要 |
PURPOSE:To stably control the etching of a deposited layer by performing a heat treatment to accelerate the alloying of the layer and a salient electrode material before etching and removing a common electrode. CONSTITUTION:After an Au plating layer 5 is formed a heat treatment is performed before etching a deposited layer 4. An Ag-Au diffused layer is formed between Ag and Au plating layers 5 for forming a buffer layer 4b by this heat treatment. Since the Ag-Au diffused layer has much slower etching speed than the etching speed of Ag to etchant of the layer 4b, the lower part of the layer 5 formed with the Ag-Au diffused layer has a wide etching time margin to the side etching with the etchant of the layer 4b and can be sufficiently allowed for the irregularity in the thickness of the layer 4. |
