| 摘要 |
PURPOSE:To obtain a device of high reliability, by stacking Si3N4, and PSG (phosphosilicate glass) on the wiring materials and forming an antiradioactive-rays film on the PSG after the formation of electrode window. CONSTITUTION:Adjacent to the N type source-drain layer 5 on the P type Si substrate, a PSG 6 is formed with a hole, and the Al7, the Si3N48 and the PSG 9 are stacked thereon. After a resist-mask is coated and a film 9 is etched so that a hole is formed, polyimide 11 is coated thereon as a protective means against the alpha rays and the portion thereof at the hole is selectively removed. Then the Si3N48 is etched away by the CF4 gas plasma. With such an arrangement, not only the etching control of the PSG film 8 is unnecessitated because of the presence of the Si3N4, but also the etching by the chemical liquid is spared to remove the Si3N48, resulting in the protection of the polyimide. Further, though the gas plasma easily etch away the Si3N4, the same hardly affect the polyimide. Therefore the device of higher reliability which is protected against the alpha rays can be obtained. |
