Application of Fin Structure Factor to Reduce the Body Effect in 20 nm DRAM Cells

Abstract

Body effect—a key characteristic of dynamic random access memory (DRAM) cell transistors—is affected by the length and width of conventional planar transistors. However, in buried channel structures developed recently, the fin structure is also known to affect the properties of a transistor. In this paper, the effect of the fin structure on the body effect of a DRAM cell is investigated. In addition, a scheme for reducing this effect is suggested. In order to measure the body effect in a DRAM cell, a nondestructive measurement method was used. This method uses a memory test system for fast, massive, nondestructive measurement. Using the measured data, we compared the body effect and the fin dimension. The results show that there is a strong correlation between the fin height and the body effect.