METHOD FOR SELECTIVELY FORMING AIR GAPS AND DEVICE OBTAINED BY THE SAME

摘要

PROBLEM TO BE SOLVED: To allow selective formation of air gaps in a semiconductor device. SOLUTION: A first dielectric material 1 having contact holes is made of hydrogenated silicon oxycarbide (SiCO:H). By using a UV/ozone treatment including an oxidizer or a process of oxidizing supercritical carbon dioxide or the like, the sidewall of each contact hole is converted into a modified material 4 containing less carbon than the first dielectric material 1. A barrier layer 5 and a copper portion 6 are formed in each contact hole. After that, the modified material 4 is removed by etching using HF to leave an air gap there. COPYRIGHT: (C)2005,JPO&NCIPI