I believe the variables would be length, width, height, and resistance
or capacitance [resistance/volume for the resistor and
capacitance/volume for the capacitor (of the poly) , where volume =
length*width*height].
The resistive voltage divider tutorial and the poly1–poly2 capacitor and
RC circuit tutorials might help at:
http://cmosedu.com/videos/electric/electric_videos.htm