A Formation Mechanism of the Defect‐Free Denuded Zone in Antimony‐Doped Epitaxial Substrate Wafers

Abstract

The effect of antimony on oxygen precipitation and formation of the defect-free denuded zone in substrate and epitaxial wafers after a two-and a three-step anneal was studied. The results show that the formation of the denuded zone is strongly affected by the epitaxial deposition process and antimony doping concentration. In interpreting this observation, a model for the formation of the defect-free denuded zone accounting for the effect of strain-free energy has been developed. This model considers that "grown-in" microprecipitate nuclei play a significant role in the formation of the denuded zone. Using the proposed model, the dependence of denuded zone width on the antimony doping concentration is hypothesized to be due to an increase in the total free-energy of an isolated precipitate. Antimony when doped at a high concentration causes an increase in the shear property of silicon and, therefore, the total free-energy of oxygen precipitates. This, in turn, causes a retardation of precipitate growth, particularly in the subsurface region where oxygen is already undersaturated.

Composition and Electrical Properties of Metallic Ru Thin Films Deposited Using Ru(C6H6)(C6H8) Precursor

“…The leakage current and breakdown characteristics of the thin gate oxide of 7 nm heat-treatment model. 9,10) The temperature of first annealing step (denudation anneal) was in the range of 1000-1200 • C, and the second step (nucleation of oxygen precipitates) anneal and the third step (growth of oxygen precipitates) anneal were performed at 780 • C for 420 min and 1000 • C for 30 min, respectively. The second and third step anneal conditions were chosen as the heat treatment condition of the actual MOS device fabrication.…”

A Formation of Crystal Defects in Carbon‐Doped Czochralski‐Grown Silicon after a Three‐Step Internal Gettering Anneal

“…As the denudation temperature increases, the DFZ width becomes broadened while the microdefect density in the bulk region decreases slightly. The dependence of the DFZ width and the microdefect density-depth distribution in the subsurface region on the denudation temperature can be interpreted as a result of oxygen out-diffusion (19). The reduction in the bulk microdefect density, on the other hand, is not related to oxygen out-diffusion because the only difference in the annealing procedures was the denudation temperature.…”

The Effect of the Crystal Grown‐in Defects on the Pause Tail Characteristics of Megabit Dynamic Random Access Memory Devices

“…16 One of the possible reasons that a device fabricated on an epitaxial wafer having a 3 ~m thick layer to exhibit a high cumulative number of fail bits, particularly near the wafer center, could be because the oxide precipitates were not completely dissolved during the high temperature steps of epitaxia] deposition and subsequent device processing. This explanation, however, cannot be confirmed in this study because a relatively wide defect-free zone was observed under the optical microscope after device processing.…”