A METHOD FOR PLASMA DEPOSITION OF A SUBSTRATE BARRIER LAYER

摘要

A method for depositing a barrier or coating layer (34) in a semiconductor recessed structure (28) within a substrate (20) using a plasma process (62) that includes alternating depositing steps (64) and resputtering steps (66). The depositing step (64) deposits a barrier layer (34), including a thick bottom region (38) and a sidewall region (40) along the recessed structure (28) surface. The resputtering step (66) reduces the barrier layer (34) thickness in the bottom region (38) and increases the barrier layer (34) thickness in the otherwise thinly covered portions of the substrate sidewall region (40). Control of powers ranges supplied to the sputtering target (14) and the substrate (20) achieve the depositing and resputtering steps. The process applies also to other coating layers than barrier layers (34), providing a uniform sidewall coverage and thin bottom coverage, e.g., for permalloy deposition in MRAM devices and dual gate electrode formation in CMOS devices.