Agglomerated vacancy-related defects are known commonly as D-defects, or as COPs when they intersect the wafer surface. Although recent data has shown a decreasing sensitivity of GOI to COPs at gate oxide thickness of less than 100Ĺ, it is believed that the presence of the vacancy-related defects will have a certain impact on device performance and yield. The benefits of OPTIA™ wafers arise because of the complete suppression of agglomerated defects, which lead to COPs and interstitial defects. Therefore, the device yield and reliability potential are improved by the use of OPTIA™ wafers.

Intrinsic Gettering

In addition to low COP densities, many customers also require intrinsic gettering. This is achieved in OPTIA™ wafers by using MEMC’s patented process Magic Denuded Zone® (MDZ®). The MDZ® process produces an ideal density of oxygen precipitates and a deep precipitate-free zone. This eliminates the need for additional, costly out-diffusion, nucleation and growth thermal cycles in the customers’ manufacturing lines.