US 12,391,570 B2
Methods of the ultra-clean transfer of two-dimensional materials
Thuc Hue Ly, Kowloon (HK); and Haijun Liu, Kowloon (HK)
Assigned to CITY UNIVERSITY OF HONG KONG, Kowloon (HK)
Filed by CITY UNIVERSITY OF HONG KONG, Kowloon (HK)
Filed on May 8, 2023, as Appl. No. 18/314,131.
Claims priority of provisional application 63/344,970, filed on May 23, 2022.
Prior Publication US 2023/0373810 A1, Nov. 23, 2023
Int. Cl. C01G 39/06 (2006.01); C23C 16/01 (2006.01); H01J 37/20 (2006.01); H01J 37/26 (2006.01)
CPC C01G 39/06 (2013.01) [C23C 16/01 (2013.01); H01J 37/20 (2013.01); C01P 2004/02 (2013.01); C01P 2004/04 (2013.01); C01P 2004/24 (2013.01); H01J 37/26 (2013.01)] 22 Claims
OG exemplary drawing
 
1. A method of transferring a two-dimensional (2D) material formed on a growth substrate to a target substrate comprising:
(a) applying a water droplet on the target substrate;
(b) covering the target substrate with the growth substrate via aligning the growth substrate with the 2D material facing down toward the target substrate so that the water droplet on the target substrate is pressed into a thin film and the 2D material on the growth substrate is immersed in the thin film of water thereby forming a sandwich structure;
(c) maintaining the sandwich structure of step (b) at a temperature between 20° C. to 80° C. for at least 10 seconds;
(d) lowering the temperature of the sandwich structure of step (c) until the thin film of water turns into a thin film of ice;
(e) peeling off the growth substrate from the sandwich structure of step (d) thereby forming an intermediate structure; and
(f) removing the thin film of ice from the intermediate structure of step (e) thereby transferring the 2D material onto the target substrate.