| 摘要 |
PURPOSE:To enable total solid printing to be carried out without causing uneveness of printing by achieving reduction of a drop in voltage between a common line pattern and a grand line pattern, by a method wherein the common line pattern and/or the grand line pattern are reinforced with a conductor of which coefficient of liner expansion is almost the same as that of a ceramic substrate. CONSTITUTION:There is a material having three layer structure of copper/invar/ copper (CIC) as an example of a conductor of which linear expansion coefficient is almost the same as that of a ceramic substrate. For this CIC, its linear expansion coefficient can be set over a wide range by changing a ratio in thickness of a copper layer to an invar layer. CIC line 21 is connected onto a common line pattern 14 by soldering. Then, since a linear expansion coefficient of the CIC line 21 is almost the same as that of the ceramic substrate 11, peeling owing to stress does not occur between the ceramic substrate and the CIC line even though variation in temperature occurs. Soldering of the CIC line 21 as well as soldering of other parts can be executed on the ceramic substrate 11, and the title LED array head substrate can be produced by the same reflow process. |
