| 摘要 |
PURPOSE:To obtain a thick silica thin layer with less stepped portions but without internal crack by coating an Si substrate with silica thin film, baking it at 200-400 deg.C, repeating such process and then processing it at a higher temperature. CONSTITUTION:An Al wiring 3 is formed and a thin film NSG4 is also formed on an insulation film 2 on an Si substrate 1 on which an element function part is formed. Next, a silica thin film 5a including phosphorus P is applied by spinning and it is vitrificated for 30min at 200-400 deg.C. In the same way, a layer 5b is laminated to form a comparatively thick silica layer, and it is then processed for 20min at 450-500 deg.C under the N2 to form a dense layer 5. Sudden volume compression of silica thin film can be avoided, internal cracks are not generated and a thick silica layer can be formed. Moreover, stepped portions are reduced, wiring is not open at the stepped portions, drop of interlayer insulation strength can be prevented and yield of apparatus can also be improved. |
