PREPARATION OF SEMICONDUCTOR DEVICE

摘要

PURPOSE:To make it possible to perform a uniform gettering, by forming a damage layer in an isolation region or a dicing region on a main surface of a semiconductor device. CONSTITUTION:An N<-> epitaxial layer on a P type Si substrate having an N<+> type buried layer is isolated by BSG layer 4. The layer 4 is coated with resist film and etched for an opening 5 by B ion implantation and a damage layer 6 is formed. Then it is covered by an oxide film to form a bi-polar IC thereon by employing the existing method. With such an arrangement, unlike the hitherto method the damage layer is formed on the main surface of the device during the preparation process. And because the gettering direction is parallel with the main surface, the uniform gettering can be performed regardless of the thickness of the wafer or the disposition in the water. Thus the scattering of the properties between each lot is decreased.