Method of fabricating a trench capacitor

Abstract

This invention provides a semiconductor device by which a high-speed DRAM cell and logic circuit can be obtained without increasing the number of fabrication steps, and a method of fabricating the same. A memory cell is constructed of capacitors formed in two end portions of an element formation region of a silicon substrate and a MOS transistor formed between these capacitors. The interval between gate electrodes of MOS transistors in adjacent memory cells is made larger than the intervals between these gate electrodes and gate electrodes formed outside the former gate electrodes. A portion above an n-type diffusion layer connected to a capacitor node is filled with a spacer insulating film, and an n-type diffusion layer connected to a bit line is covered with the spacer insulating film. A titanium silicide film is formed on one of these n-type diffusion layers and the gate electrodes. In a first transistor in a memory cell array, a metal silicide film is not formed on the surfaces of source and drain diffusion layers and is formed only on the surface of a gate electrode. In a second transistor in a logic circuit, a metal silicide film is formed on the surfaces of source and drain diffusion layers and a gate electrode.