| 摘要 |
PURPOSE:To prevent the alpha ray soft error by a method wherein the inside of the first groove of the grooves separating the semiconductor element regions is filled with a conductor such as metals, and the inside of the second groove is filled with insulating material, thereby making it possible to add a capacity to the collector side. CONSTITUTION:In an IC in which the semiconductor element region 13 consisting of epitaxial layers is separated with grooves 16a and 16b which are formed on the first main plane on a P-type semiconductor substrate 11 and also whose inner sides are filled with a oxide film 17, the inside of the first groove 16a is filled with polysilicon 18a which is doped with high-density boron up to the height of the surface of the semiconductor substrate 11, and the inside of the second groove 16b other than that is filled with genuine polysilicon 18 up to the height of the surface of the semiconductor 11. Two capacities are formed between the semiconductor region 13 and the groove 16a through the oxide film 17. Therefore, a pair of transistors of a flip-flop consisting the memory cell of a Bip RAM is formed in a semiconductor element region 13 and whose collector is connected to the said capacity so as to increase the capacity to be attached to the pair of transistors without especially increasing the area of the chip. |
