US 12,424,520 B2
Semiconductor device with back-side via structure
Ta-Chun Lin, Hsinchu (TW); and Jhon-Jhy Liaw, Hsinchu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed on Feb. 23, 2023, as Appl. No. 18/173,627.
Claims priority of provisional application 63/433,219, filed on Dec. 16, 2022.
Prior Publication US 2024/0203829 A1, Jun. 20, 2024
Int. Cl. H01L 23/48 (2006.01); H10D 30/67 (2025.01); H10D 64/01 (2025.01)
CPC H01L 23/481 (2013.01) [H10D 30/6735 (2025.01); H10D 30/6757 (2025.01); H10D 64/021 (2025.01)] 20 Claims
OG exemplary drawing
 
15. A semiconductor device comprising:
a substrate having an upper side and a lower side opposite to each other;
a transistor structure disposed on the upper side of the substrate, and including a pair of epitaxial structures spaced apart from each other and a channel feature extending in a channel length direction to be disposed between the epitaxial structures;
a back-side via structure disposed on the lower side of the substrate and extending through the substrate, the back-side via structure being connected to a corresponding one of the epitaxial structures, the back-side via structure being formed with an upper surface on opposite sides of the corresponding one of the epitaxial structures in a channel width direction transverse to the channel length direction and a recessed surface which is recessed inwardly from the upper surface, the back-side via structure being connected to a lower portion of the corresponding one of the epitaxial structures; and
a sidewall spacer directly on the upper surface of the back-side via structure and directly contacting the opposite sides of the corresponding one of the epitaxial structures,
wherein the recessed surface has a bottom surface portion directly connected to a bottom surface of the lower portion of the corresponding one of the epitaxial structures, and a first sidewall surface portion extending between the upper surface of the back-side via structure and the bottom surface portion of the recessed surface and connected to a first side of the opposite sides of the lower portion of the corresponding one of the epitaxial structures.