Characterization of the surface structural, mechanical, and thermal properties of benzocyclobutene dielectric polymers using scanned probe microscopy

Scanning probe microscopy (SPM) techniques are used to characterize surface s related to the processing of benzocyclobutene (BCB) dielectric thin films . Thermally cured resins and photodefineable resins are sold under the trad e name CYLCOTENETM1) for electronic applications. TappingMode AFM (TMAFM) i maging is used to follow changes in adhesion promoter morphology upon bakin g to help explain adhesion performance. Power spectral density (PSD) analys is of TMAFM images of plasma treated BCB surfaces are unique and can be use d to 'fingerprint' processes. Selective oxidation of the BCB surface can be used to fabricate a phase imaging standard for TMAFM. Near surface modulus of the BCB materials is 3.6 +/- 0.2 GPa and the hardness is 0.38 +/- 0.2 G Pa measured by depth-sensing nanoindentation. Creep recovery of indents can be used to qualitatively distinguish between thermal and photocureable mat erials. A heated tip in a scanning thermal microscope can induce the therma l curing of BCB over micron sized areas. Local thermal analysis with the sa me probe allows the measurement of the changes in the glass transition, T,, at the surface with cure temperature.