| 摘要 |
PURPOSE:To prevent the double-sided substrate from degrading in solder- wettability and realize an even bonding strength between the top and rear sides by providing a number of ambient gas delivery outlets which deliver the ambient gas from under the conveyer belt to the rear side of the substrate. CONSTITUTION:A number of delivery outlets 10, 11 are disposed in two separate blocks in the muffle bottom in the burnout section 4, and eject nitrogen ambient gas from under the mesh belt 2. Another set of ambient gas delivery outlets 12, 13 are disposed in two separate blocks in the muffle bottom in the firing section 5, and eject nitrogen ambient gas from under the mesh belt 2. In this constitution, nitrogen gas is jetted to both sides of the alumina substrate having copper pattern printed on both sides in the burnout section 4 to remove organic substances of decomposed vehicle components in the copper paste, and clean nitrogen gas can always be supplied to the top and rear sides of the substrate which is being fired in the firing section 5. As a result, the calcinating of the copper paste can be performed uniformly on both the side. |
