Abstract: Semiconductor devices and methods of manufacturing the semiconductor devices are provided. The methods may include forming a sacrificial gate pattern on a substrate, forming a first spacer on a sidewall of the sacrificial gate pattern and forming a first interlayer dielectric (ILD) layer covering a sidewall of the first spacer and exposing a top surface of the first spacer. The first spacer may expose an upper portion of the sidewall of the sacrificial gate pattern. The methods may also include forming a capping insulating pattern covering top surfaces of the first spacer and the first ILD layer, replacing the sacrificial gate pattern with a gate electrode structure and patterning the capping insulating pattern to form a second spacer on the first spacer and between the gate electrode structure and the first ILD layer. The second spacer may be formed of a material having a dielectric constant higher than a dielectric constant of the first spacer.

Abstract: A semiconductor device is manufactured using an expandable material. The method includes forming a first gate insulating layer on a substrate, forming first and second gate structures on the first gate insulating layer, the first and second gate structures being spaced apart from each other at a distance, forming an expandable material on sidewalls and upper surfaces of the first and second gate structures, forming a gap-fill layer on the expandable material between the first and second gate structures, and performing a heat-treatment process to increase the volume of the expandable material.

Abstract: A method of manufacturing a semiconductor device can uniformly form a metal gate irrespective of gate pattern density. The method includes forming an interlayer dielectric layer having a trench on a substrate, forming a metal layer having first, second and third sections extending along the sides of the trench, the bottom of the trench and on the interlayer dielectric layer, respectively, forming a sacrificial layer pattern exposing an upper part of the first section of the metal layer, forming a spacer pattern on the exposed part of the first section of the metal layer, and forming a first gate metal layer by etching the first section of the metal layer using the sacrificial layer pattern and the spacer pattern as masks.