Patent ID: 9159907
Filing Date: 2015-10-13
Classification: H01L

Abstract:
1. A method comprising: patterning a plurality of magnetic tunnel junction (MTJ) layers to form a MTJ stack; forming a first dielectric cap layer over a top surface and on a sidewall of the MTJ stack, wherein the first dielectric cap layer is formed using radical shower chemical vapor deposition (RSCVD), wherein the step of patterning and the step of forming the first dielectric cap layer are in-situ formed in a same vacuum environment; and forming a second dielectric cap layer over and contacting the first dielectric cap layer, wherein the second dielectric cap layer is formed using plasma enhanced chemical vapor deposition (PECVD), wherein the first dielectric cap layer and the second dielectric cap layer are formed of a same dielectric material, and a first density of the first dielectric cap layer is different from a second density of the second dielectric cap layer.