SEMICONDUCTOR MEMORY DEVICE

PURPOSE:To reduce a necessary area and improve a reliability by a method wherein an insulation film and a conductive film are laminated on the surface of a column shape part to form a capacitance part. CONSTITUTION:Gold is implanted into the position in a silicon substrate where a column shape part is to be formed by a converged ion beam method. The size of a gold-silicon alloy region can be controlled so as to have a diameter within a region about 0.2-10mum by regulating the diameter and the intensity of the ion beam. If the substrate is heated to the temperature not less than 370 deg.C, which is the eutectic temperature of gold-silicon alloy, in a cylinder type reaction furnace, a gold-silicon eutectic alloy liquid drop is formed at the position where the gold is implanted. If the substrate is placed in the reaction furnace whose inside temperature is maintained at 375 deg.C and SiCl4/H2 system mixture gas is introduced and made to react by a photoexcitation method, supersaturated silicon is deposited from the alloy liquid drop to make a column shape silicon single crystal grow. With this constitution, a necessary area can be significantly reduced and an integration density can be improved.