Synthesis of Polymer films with low Dielectric Constant (k)

Abstract

The semiconductor industry and Microelectronics based devices are in urgent need of materials having low dielectric constant (κ). Efforts are being made, world over, to develop low dielectric (say κ < 2.0) materials for microelectronic applications It is thus of interest to develop materials having low dielectric constant (κ). Polyimide is widely used as packaging material in microelectronic devices packaging due to its good thermal and mechanical properties and good adhesion to metal surfaces. However, the dielectric constant of normal PI is high (κ ∼3.4) as per the requirement of advance insulator material and for microelectronics. We have synthesized polyimide- silica composite films and it is shown that such films have much lower dielectric constant as compared to the normal PI films. The above polymer films were prepared by modifying the pristine polymer at the precursor stage of synthesis. We report the results of FTIR, XRD and dielectric studies of films which have been prepared using PMDA-ODA (Poly Amic acid in DMAc) as precursor and Tetra Ethoxy Silane (TEOS)/Silicic acid as modifier It is seen that crystallinity and the dielectric of the composite films depend on SiO2 concentration.