Palladium-Test: A Tool to Evaluate Gettering Efficiency

Abstract

ABSTRACTA new method is presented which is suitable to check gettering processes and to evaluate gettering efficiencies. This method is based on an intentional contamination of the respective silicon wafer by means of palladium or any other haze forming metal. The palladium is diffused and haze is revealed by preferential etching. In order to determine gettering efficiency the sizes of the haze areas on gettered and non-gettered wafers are compared. The quantity of the gettered palladium can be deduced from lateral palladium profiles.In contrast to procedures published in the literature this method is very simple and fast. Therefore it is suitable for routine application to check back side damaged wafers or internal gettering.