J.L. Hedrick, R. Dipietro, et al.
High Performance Polymers
Thin polyimide films with dispersed nano-foam morphology have been prepared for the purpose of obtaining low dielectric polymer insulators for microelectronic applications. They were obtained by utilizing micro phase-separated triblock copolymers where the thermally stable polyimide matrix component was derived from pyromellitic dianhydride (PMDA) with 1,1-bis(4-aminophenyl)-1-phenyl-2,2,2-trifluoroethane (3F) and a thermally labile poly(propylene oxide)(PO) component comprised the outside block of the ABA triblock architecture. TEM studies show that the initial irregular nanoscale phase-separated morphology of polyimide triblock copolymers are mostly maintained in the final nano-foam films upon thermal decomposition of the dispersed PO component. The nano-foam polyimide films exhibit significantly lower dielectric constants ε′ (e.g., 2.3 at 19% porosity) as compared with ε′≊2.9 for the homopolymer, as predicted by Maxwell-Garnett theory, with the nano-pore structures remaining stable at 350°C. © 1996 American Institute of Physics.
J.L. Hedrick, R. Dipietro, et al.
High Performance Polymers
J.L. Hedrick, T.P. Russell, et al.
J Polym Sci Part A
K.R. Carter, Richard DiPietro, et al.
Chemistry of Materials
R.J. Twieg, D.M. Burland, et al.
MRS Fall Meeting 1993