US 11,694,923 B2
Method for preparing semiconductor device with air spacer
Jung-Hsing Chien, Taoyuan (TW)
Assigned to NANYA TECHNOLOGY CORPORATION, New Taipei (TW)
Filed by NANYA TECHNOLOGY CORPORATION, New Taipei (TW)
Filed on Jul. 6, 2021, as Appl. No. 17/367,973.
Application 17/367,973 is a division of application No. 16/547,099, filed on Aug. 21, 2019, granted, now 11,121,029.
Prior Publication US 2021/0335656 A1, Oct. 28, 2021
Int. Cl. H01L 21/768 (2006.01); H01L 23/528 (2006.01); H01L 23/532 (2006.01); H01L 23/522 (2006.01)
CPC H01L 21/7682 (2013.01) [H01L 21/76885 (2013.01); H01L 23/528 (2013.01); H01L 23/5226 (2013.01); H01L 23/5329 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method for preparing a semiconductor device, comprising:
forming a plurality of composite pillars over a substrate, wherein the composite pillars include conductive pillars and dielectric caps over the conductive pillars;
transforming a sidewall portion of the conductive pillar into a first transformed portion;
removing the first transformed portion such that a width of the dielectric cap is greater than a width of a remaining portion of the conductive pillar;
forming a supporting pillar between adjacent two of the plurality of composite pillars; and
forming a sealing layer at least contacts a top portion of the supporting pillar and a top of the dielectric cap, and air spacers are formed between the sealing layer, the supporting pillar and the remaining portions of the conductive pillars;
wherein the sealing layer has an intervening portion contacting the top portion of the supporting pillar and the top portion of the dielectric cap, and the intervening portion has a bottom end lower than a bottom end of the dielectric cap.