Oxidation induced stacking faults in n- and p-type (100) silicon

Abstract

The formation of stacking faults during thermal oxidation of silicon has been investigated. The length and the density of stacking faults, in both n‐ and p‐type 5‐cm‐diam (100) silicon wafers obtained from various manufacturers, were determined as a function of time and temperature of oxidation in dry and steam ambients. There appeared to be two categories of stacking faults. In the first category, the length of the stacking fault was given by L= (const) tⁿ exp(−Q/kT), where n and Q are, respectively, 0.85 and 2.55 eV for dry oxidation and 0.66 and 2.37 eV for steam oxidation. This length was independent of the type (p or n) of the wafer. In the second category, the length of the stacking faults varied randomly across the wafer surface. The number of such faults was only about 5% of the total. For a given oxidation condition, the density of the stacking faults was an order of magnitude or more higher in n‐type wafers than that in p‐type wafers. Except for the very short periods of oxidation (<20 min) the density was found to be nearly independent of time or temperature of oxidation.