Semiconductor structure and manufacturing method thereof

The invention discloses a semiconductor structure and a method of fabricating the semiconductor structure. The method includes the steps: forming a first dielectric layer on a substrate, forming a plurality of first interconnect structures in the first dielectric layer, forming at least one trench in the first dielectric layer between the plurality of first interconnect structures, performing a sputter deposition process to form a second dielectric layer on the first dielectric layer, where the second dielectric layer at least partially seals an air gap in the trench; and forming a third dielectric layer on the second dielectric layer. 本发明公开了一种半导体结构及其制作方法，包括形成一第一介电层于一基底上，在该第一介电层中形成多个第一互连结构，在该多个第一互连结构之间的该第一介电层中形成至少一沟槽，进行一溅镀沉积制作工艺于该第一介电层上形成一第二介电层，其中该第二介电层至少部分封口该沟槽中的一气隙，以及于该第二介电层上形成一第三介电层。