| 摘要 |
PURPOSE:To provided a protection element of high pressure-resistance on the same substrate simultaneously by utilizing the manufacturing process for a group of elements of standard pressure-resistance. CONSTITUTION:By using an Si3N4 mask, a p type channel cut CC is provided and a field oxidized film 2 is prepared selectively. Next, openings are made in a gate oxidized film as well as in SiO26 on an n layer 3D, an electrode 7 together with a poly-Si gate electrode is prepared, and an end rim 7a is extended on to SiO22, while SiO26 on an n layer 3S is removed. With the intermediate presence of SiO26, the n layer 3D and the separating layer CC are isolated from each other. After that, the device is covered with PSG5 and electrodes 4D and 4S are attached thereto. When high voltage is applied to the electrode 4D and the junction between the substrate 1 and the n layer 3 is subjected to inverse bias, electrons in the substrate 1 and the separating layer CC are attracted, a positive hole is moved out and turned inversely into a part 10 in n type, thereby an electric field becomes hard to concentrate, and thus the pressure resistance of a horizontal-type npn element for protection is raised. |
