| 摘要 |
<p>PURPOSE:To facilitate forming a semiconductor device with a high density, a high speed and a high reliability by a method wherein a semiconductor element is electrically isolated by U-shape grooves and an electrode pad is electrically isolated by a P-N junction. CONSTITUTION:After an n-type buried layer 13 is formed in a p-type Si substrate 12, an n-type epitaxial layer 14 is formed. On a semiconductor element side, U-shape grooves are formed after this process and further, after an SiO2 film is formed on the surfaces of the U-shape grooves, the grooves are filled with polycrystalline Si. Then, oxidization is carried out by a LOCOS method with an Si3N4 film 15 as a mask to form an SiO2 film 16. Then boron ions are implanted with a resist film 17 as a mask. Then, by removing the Si3N4 film 15 and oxidizing the whole surface, an SiO2 film 18 and p<+>type diffused layers 19 are formed. After that, an Al layer is formed and patterned to form an Al electrode pad 20. With this constitution, the Al electrode pad 20 isolated electrically by a P-N junction and the semiconductor element isolated electrically by the U-shape grooves can be completed.</p> |
