| 摘要 |
PURPOSE:To shorten the forming process of an electrode window, by a method wherein the window is made to SiO2 on Si substrate, covered with BPSG film, and then the window is opened again, the surface is melted to be smooth. CONSTITUTION:The first opening is made to the SiO2 film 2 on the Si substrate, P treatment is performed and after Na ion in the film 2 is removed, BPSG 3 is piled. Next, the second opening is made with the same mask. In this case, different from the conventional method, BPSG is not annealed, which has different etching ratio from SiO2, and taper is easily formed. Then, the opening is melted smoothly. In this constitution, the conventional BPSG annealing process is omitted, which enable working process to curtail remarkably. |
