THERMAL-STABILITY STUDIES OF A POLYIMIDE POLYTETRAFLUOROETHYLENE BLEND AND ITS COMPONENTS

Low-dielectric constant (epsilon(r)) polymers, such as polytetrafluoro ethylene (PTFE), are an important component of advanced electronic pro ducts that transmit data, since it is this physical property that larg ely determines a device's performance. For instance, the dielectric co nstant determines overall signal speed and proximity in that one circu it line can be placed to another, i.e., wiring density, while maintain ing desired electrical characteristics. However, due to PTFE's inertne ss and intractability, significant challenges exist in the successful application of the polymer as an insulation material. One specific exa mple is the lack of available methods to uniformly and controllably ge nerate fine, high-density features in the neat fluoropolymer. Recently , it was reported that excellent structuring characteristics of PTFE c an be achieved by sensitizing the fluoropolymer to excimer laser radia tion using small quantities of an aromatic polyimide. An important phy sical property of the sensitization agent, in addition to interacting strongly with the laser's emitted energy, is suitable thermal stabilit y due to PTFE's high-temperature processing requirements. Using multip le analysis techniques, the thermal decomposition behavior of PTFE, po lyimide sensitizer, and resulting polymer blend have been evaluated. I t was determined that the onset of decomposition for all systems is ne ar or greater than 500-degrees-C. (C) 1994 John Wiley & Sons, Inc.