APPROXIMATING SPUN-ON, THIN-FILM PLANARIZATION PROPERTIES ON COMPLEX TOPOGRAPHY

A method for characterizing and estimating spun-on, thin film planarization properties is proposed. The spun-on film is considered to be a low pass frequency filter. Two adjustable parameters are used to weight the frequencies to experimental planarization data for isolated line features. Using these parameters, the planarization properties on more complex topographies having a nominal unity of step height can be accurately estimated. One fitting parameter, a, gives an indication of the planarization (flow) properties of the spun-on solution. The other fitting parameter, Pmin, represents the minimum period (maximum frequency) with a weighting factor equal to one. Planarization properties of two distinctly different spun-on solutions are simulated on complex topography to verify the approximation procedure. The stencil pattern used to obtain the experimental planarization data for isolated line features can also be used to obtain an unambiguous determination of the planarization properties independent of step height and the spun-on film thickness. © 1985, The Electrochemical Society, Inc. All rights reserved.