High temperature polyimide nanofoams based on 9-phenyl-9-(trifluoro-methyl) xanthene-2,3,6,7-tetracarboxylic dianhydride

Conference · Fri Dec 01 04:00:00 EST 1995

OSTI ID:126945

Lakshmanan, P; Srinivas, S; Wilkes, G L ^[1]

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1. Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States); and others

Polyimides are a class of materials that have been extensively used in the microelectronics industry in passivation and protection. Their excellent thermal stabilities, along with desirable electrical and mechanical properties, have led to their use in integrated circuits and thin film multilayer packaging. Stringent demands placed on the improvement of performance and speed of propagation of the packaging systems, have resulted in a search for newer materials with lower dielectric constants. In this research we have attempted to decrease the dielectric constant of the polyimides by utilizing the concept of a foamed morphology. Microphase separated block and graft copolymers of polyimides and propylene oxide (PO) were synthesized. Fluorinated matrices having low dielectric constants and inherently low water absorption were used as stable, polyimide components. Thermolysis of the minor propylene oxide component, resulted in well distributed, closed cell pores less than a 100 mn in size. The presence of pores has been confirmed by Small Angle X-ray Scattering and Transmission Electron Micrography. In addition, Wide Angle X-ray Diffraction performed on the cured films and foams revealed the existence of order in these materials. Reasonable foam efficiencies and virtually no collapse of the porous structure up to 350{degrees}C suggests improved foam stabilities resulting from the presence of order in these materials.

• OSTI ID: 126945
• Report Number(s): CONF-950402--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
COPOLYMERS
DIELECTRIC PROPERTIES
GRAFT POLYMERS
IMIDES
INTEGRATED CIRCUITS
MECHANICAL PROPERTIES
MICROELECTRONICS
MORPHOLOGY
ORGANIC POLYMERS
PASSIVATION
PROPYLENE
SCATTERING
X-RAY DIFFRACTION