High pressure oxidation induced stress in submicron trench structures

摘要

The maximum stress induced by high pressure oxidation (wet and dry) in the vertical birdrsquo;s beak of submicron trench structures has been investigated experimentally. The oxidation induced stress was measured via wafer bow on wafers that were patterned with a special trench mask featuring a pattern factor of 50percnt;. For wet high pressure oxidations above 850thinsp;deg;C, the stress drops from 2times;1010dyne/cm2at 850thinsp;deg;C to a value below 1times;109dyne/cm2at 1000thinsp;deg;C. At oxidation temperatures between 700 and 900thinsp;deg;C, dry pressure oxidations show lower stress than wet oxidations. copy;1996 American Institute of Physics.