No CrossRef data available.
Published online by Cambridge University Press: 10 February 2011
Using an improved version of the thermal pulse (TP) method for determining electric field profiles and thermal parameters, we have obtained for the first time field profiles in 1.7 μm thick polyimide (PI) films spin-coated on Si wafers. As-coated films were found to have an internal field caused by negative charges within 200 nm of the free (pulsed) surface believed due to electrochemical reactions involving water. The change near the pulsed surface was stable up to 200 °C and would not be switched by applied fields of ±1 V/μm. The charge distribution and the thermal parameters were found to be sensitive to humidity