碩士 國立清華大學 電子工程研究所 88 As the ULSI circuits are scaled down, the linewidth and spacings between metal interconnect also are made smaller, transmission delay is primarily caused by the parasitic resistance and capacitance(RC) along the metallic lines. There are two principle methods of reducing the transmission delay. The first method is to replace the aluminum wires with copper interconnects which offer lower resistivity and high resistance to electromigration. The second method is to use a lower dielectric constant material as the inter-metal dielectric. In addition, owing to the severe depth of focus(DOF) budget in deep sub-micron lithography, chemical mechanical polishing(CMP) is the only enabling technique known to achieve global planarization. For this reason, the characteristics of low dielectric constant material after chemical mechanical polishing(CMP) process must be researched in the future. In this thesis, one of the most promising low-k materials, hydrogen silsesquioxane (HSQ) from Dow Corning Inc.,