March 2014
Intermediate to advanced
624 pages
26h 33m
English
7.1 Given the data of Prob. 5.2 , plot the doping profiles Na(x) and Nd(x) for the following double-diffused transistor: The starting wafer is n-type Si with Nd = 1016 cm−3; Ns = 5 × 1013 cm−2 boron atoms are deposited on the surface, and these atoms are diffused into the wafer at 1100°C for 1 hr (D = 3 × 10−13cm2/s for B in Si at 1100°C); then the wafer is placed in a phosphorus diffusion furnace at 1000°C for 15 min (D = 3 × 10−14 cm2/s for P in Si at 1000°C). During the emitter diffusion, the surface concentration is held constant at 5 × 1020 cm−3. You may assume that the base doping profile does not change appreciably during the emitter diffusion, which takes place at a lower temperature and for a shorter time. Find the width ...