MEMORY CELL AND MANUFACTURE THEREOF

摘要

PURPOSE:To enable to form a reversely conductive type high concentration impurity region of a memory cell without discrepancy of position by a method wherein impurities contained in a dielectric film of the capacitor part are made to diffuse in a substrate by the thermal treatment after a capacitor electrode is formed. CONSTITUTION:The dielectric film 7 being mixed with impurities and a polycrystalline Si layer 1 to constitute the capacitor electrode are adhered selectively on the whole surface of the P type substrate 4 having field oxide films 5. The surface thereof is oxidized to form a gate dielectric film 8 of transfer MOSFET, and a gate electrode 2 is adhered. After patterning of the dielectric film 7 is performed, the high concentration impurities adder region 6 of the capacitor part is formed by thermal diffusion of impurities contained therein to the substrate. Accordingly the electrode region can be formed accurately in high concentration without discrepancy of positions.