SEMICONDUCTOR ISOLATION STRUCTURE WITH AIR GAPS IN DEEP TRENCHES

摘要

According to the embodiment of the present invention, a device includes a semiconductor substrate, a contact plug which is located on the semiconductor substrate, and an interlayer dielectric (ILD). The contact plug is arranged on the ILD. An air gap is sealed by a part of the ILD and the semiconductor substrate. The air gap forms a full air gap ring which surrounds the part of the semiconductor substrate.