Abstract: A semiconductor memory device includes a plurality of bit line structures including bit lines extending in parallel in a first lateral direction on a substrate, and a plurality of buried contacts and a plurality of landing pads. The plurality of buried contacts fill lower portions of spaces between the plurality of bit line structures on the substrate, and the plurality of landing pads fill upper portions of the spaces between the plurality of bit line structures and extend on the plurality of bit line structures. The plurality of landing pads have a hexagonal array structure, and central points of respective top surfaces of a first landing pad, a second landing pad, and a third landing pad, which are adjacent to each other from among the plurality of landing pads, are connected by a scalene triangle.

Abstract: The present invention relates to polymer beads having a water-insoluble inorganic compound encapsulated therein, and their preparation method and use. In the present invention, the water-insoluble inorganic compound which has limitations on its use because of the characteristic of precipitates in an aqueous solution is encapsulated in the polymer beads. This encapsulation provides an increase in the utility of the water-insoluble inorganic compound and at the same time, imparts the activity of the water-insoluble inorganic compound to the polymer, thus increasing the function of the polymer. Accordingly, the polymer beads having the water-insoluble inorganic compound encapsulated therein, which are prepared by the inventive method, can be advantageously used in various fields, including medical and electronic industries.