US 12,456,619 B2
Method of fabricating thin, crystalline silicon film and thin film transistors
Ramesh Kumar Harjivan Kakkad, New Taipei (TW)
Filed by Ramesh Kumar Harjivan Kakkad, New Taipei (TW)
Filed on Sep. 13, 2023, as Appl. No. 18/466,657.
Application 18/466,657 is a division of application No. 16/938,851, filed on Jul. 24, 2020, granted, now 11,791,159.
Application 16/938,851 is a continuation in part of application No. 16/745,912, filed on Jan. 17, 2020, granted, now 11,562,903, issued on Jan. 24, 2023.
Claims priority of provisional application 62/963,439, filed on Jan. 20, 2020.
Claims priority of provisional application 62/944,446, filed on Dec. 6, 2019.
Claims priority of provisional application 62/793,437, filed on Jan. 17, 2019.
Prior Publication US 2023/0420254 A1, Dec. 28, 2023
Int. Cl. H01L 21/02 (2006.01); H10D 30/01 (2025.01); H10D 30/67 (2025.01); H10D 62/834 (2025.01)
CPC H01L 21/02667 (2013.01) [H01L 21/0245 (2013.01); H01L 21/02532 (2013.01); H01L 21/02573 (2013.01); H01L 21/02592 (2013.01); H01L 21/02672 (2013.01); H10D 30/0314 (2025.01); H10D 30/0321 (2025.01); H10D 30/6731 (2025.01); H10D 30/6745 (2025.01); H10D 62/834 (2025.01); H01L 21/02496 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method of producing a reduced-defect density crystalline silicon film, comprising:
forming a Six1Ge1-x1 film on a substrate, x1 having a value between zero and one not including zero, the Six1Ge1-x1 film being amorphous at formation and having a first thermal budget for crystallization;
forming a Six2Ge1-x2 film on the Six1Ge1-x1 film, x2 having a value between zero and one including zero, the value of x2 being smaller than the value of x1, the Six2Ge1-x2 film being amorphous at formation and having a second thermal budget for crystallization, the second thermal budget being lower than the first thermal budget, the Six2Ge1-x2 film being spaced apart from the substrate by the Six1Ge1-x1 film;
forming a silicon film on the Six2Ge1-x2 film, the silicon film being amorphous at formation; and
annealing to crystallize the Six1Ge1-x1 film, the Six2Ge1-x2 film, and the silicon film, such that crystallization is initiated within the Six2Ge1-x2 film and propagates through the silicon film and the Six1Ge1-x1 film, transforming the silicon film to a reduced-density, crystallized silicon film.