Wafer charging in process equipment and its relationship to GMR heads charging damage

Significant know-how and understanding of device charging damage in processing equipment exists in complementary metal oxide semiconductor (CMOS) integrated circuit (IC) manufacturing. This paper introduces the basic charging mechanisms responsible for gate oxide damage in CMOS ICs, illustrates these mechanisms with examples of measurements obtained in contemporary IC processing equipment, and shows how this knowledge could be applied to the control of charging damage in GMR heads wafer processing. A wafer charging characterization method successfully used by integrated circuit and equipment manufacturers to quantify wafer charging in process equipment is also described.