PROBLEM 9 A 10-kS2 polysilicon resistor is to be made out of material with a sheet resistivity of 100 S2 per square. (a) Determine the minimum dimensions of this resistor if the width cannot be con- trolled to an uncertainty of better than 0.2 um, and if the variation in resistance due to width variation must be kept below 5%. For simplicity, assume a straight- forward linear layout. 166 CHAPTER 4 CHARACTERISTICS OF PASSIVE IC COMPONENTS (b) Determine the parasitic capacitance to the substrate if the oxide dielectric layer (relative dielectric constant: 3.9) is 1 um thick. Using a single RC model for this structure, what is the approximate maximum frequency above which this resistor ceases to appear predominantly resistive