METHOD OF FORMING COPPER DISTRIBUTION WITH A THICK COBALT-CONTAINING INSERT IN THE STRUCTURE OF DEVICES OPERATING BASED ON MAGNETIC TUNNEL JUNCTION Russian patent published in 2019 - IPC H01L21/28 

FIELD: manufacturing technology.

SUBSTANCE: disclosed is a method of forming copper distribution with a thick cobalt-containing insert in the structure of devices operating based on magnetic tunnel junction. As a result of the method implementation, according to 3 versions, a groove with copper distribution and a cobalt insert without defects is formed. Method includes the following steps in the following sequence: etching the groove in silicon dioxide on silicon; deposition of cobalt insert; copper inoculating layer deposition. According to the first version of CMP invention seed layer copper and cobalt process is divided into 2 stages. At the first step, after depositing the copper seed layer using the CMP, cobalt is completely removed from the SiO₂ top surface. Thereafter, copper is galvanically deposited. At the second stage, the CMP is performed by removing copper from the upper surface of the groove and the upper surface of SiO₂. According to the second version of the invention, the cobalt insert is formed between two barrier layers of Ta (TaN) and/or Ti (TiN) with only one CMP process and removal of cobalt from the upper surface of SiO₂. According to the third version of the invention, at the beginning, creating a standard structure with a groove filled with a cobalt insert, depositing a thick seed layer of copper, without further use of the electrochemical deposition of copper to thickness of more than 2,000 nm, which actually enables to avoid the process of galvanic copper deposition, use only one CMP process to achieve the result, during which copper and cobalt are removed from the surface of silicon oxide, forming a groove with copper distribution and cobalt inserts without defects.

EFFECT: invention provides reduced number of defects in the process of formation of distribution.

9 cl, 9 dwg