High-Temperature Properties of a Low Dielectric Constant Organic Spin-on Glass for Multilevel Interconnects

In this paper, we report on the thermal properties of a low-dielectric-constant organic spin-on glass, methyl silsesquioxane (MSQ), an important material for semiconductor device fabrication. The compositional and structural changes of this MSQ material, when heated in air and N 2 , were investigated in detail with Fourier transform infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA). MSQ transforms to thermal oxide SiO 2 above 500 °C when heated in air, and it forms oxygen-deficient SiO 2 above 700 °C in N 2 . Our results suggest that a cure temperature higher than the current 425 °C is preferred to form films with better cross-linked network structure.