US 12,069,963 B2
Magnetic random access memory device and formation method thereof
Harry-Hak-Lay Chuang, Hsinchu County (TW); Sheng-Chang Chen, Hsinchu County (TW); Hung Cho Wang, Taipei (TW); and Sheng-Huang Huang, Hsinchu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed on Aug. 30, 2021, as Appl. No. 17/461,243.
Prior Publication US 2023/0061985 A1, Mar. 2, 2023
Int. Cl. H10N 50/80 (2023.01); H10B 61/00 (2023.01); H10N 50/01 (2023.01); H10N 50/85 (2023.01)
CPC H10N 50/80 (2023.02) [H10B 61/00 (2023.02); H10N 50/01 (2023.02); H10N 50/85 (2023.02)] 20 Claims
OG exemplary drawing
 
1. A magnetic random access memory (MRAM) device, comprising:
a substrate comprising a first inter-layer dielectric (ILD) layer having a metal line;
a first bottom electrode over the metal line;
a first MTJ stack over the first bottom electrode, comprising:
a pinned layer;
a tunnel barrier layer over the pinned layer; and
a free layer over the tunnel barrier layer;
a first spacer surrounding sidewalls of the first MTJ stack;
a topography-smoothing layer extending over a top surface of the first ILD layer, along a sidewall of the first bottom electrode and along a sidewall of the first spacer, wherein the topography-smoothing layer has a top portion over the first MTJ stack and a first side portion laterally surrounding the first spacer, and the first side portion has a maximal lateral thickness greater than a maximal vertical thickness of the top portion; and
a second inter-layer dielectric (ILD) layer over the topography-smoothing layer, wherein the second ILD layer has a material different from a material of the topography-smoothing layer.