US 12,218,142 B2
Display device
Ki Hyun Kim, Hwaseong-si (KR); Young Gil Park, Anyang-si (KR); Jin Suk Lee, Gwangmyeong-si (KR); Jai Sun Kyoung, Cheonan-si (KR); and Sug Woo Jung, Hwaseong-si (KR)
Assigned to Samsung Display Co., Ltd., Yongin-si (KR)
Filed by SAMSUNG DISPLAY CO., LTD., Yongin-si (KR)
Filed on Nov. 13, 2023, as Appl. No. 18/508,227.
Application 18/508,227 is a continuation of application No. 16/935,063, filed on Jul. 21, 2020, granted, now 11,817,458.
Claims priority of application No. 10-2019-0159525 (KR), filed on Dec. 4, 2019.
Prior Publication US 2024/0088158 A1, Mar. 14, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H01L 27/12 (2006.01); H01L 21/02 (2006.01); H10K 59/121 (2023.01); H10K 77/10 (2023.01)
CPC H01L 27/1218 (2013.01) [H01L 27/1225 (2013.01); H01L 27/1248 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A display device, comprising:
a substrate;
a polycrystalline silicon film on the substrate, the polycrystalline silicon film including a first surface facing the substrate and a second surface opposite to the first surface;
a first buffer film between the substrate and the polycrystalline silicon film;
a second buffer film between the substrate and the polycrystalline silicon film, the second buffer film including one surface contacting the first surface of the polycrystalline silicon film and another surface opposite to the one surface; and
a gate insulating layer disposed on the polycrystalline silicon film, the gate insulating layer contacting the second surface of the polycrystalline silicon film,
wherein a thickness of the second buffer film is different from a thickness of the first buffer film,
wherein the second surface of the polycrystalline silicon film has a third root mean square (RMS) roughness range,
wherein the third RMS roughness range is more than 1.5 nm,
wherein the polycrystalline silicon film includes hydrogen ions, and an average concentration of the hydrogen ions in a vicinity of the first surface of the polycrystalline silicon film is greater than an average concentration of the hydrogen ions in a vicinity of a center of the polycrystalline silicon film,
wherein the vicinity of the center of the polycrystalline silicon film is defined as a first region which is a section of the polycrystalline silicon film extending from a center point of the polycrystalline silicon film toward the first surface of the polycrystalline silicon film by a depth of 50 Å, and extending from the center point of the polycrystalline silicon film toward the second surface of the polycrystalline silicon film by a depth of 50 Å, and
wherein the vicinity of the first surface of the polycrystalline silicon film is defined as a second region which is a section of the polycrystalline silicon film extending from the first surface of the polycrystalline silicon film toward the second surface of the polycrystalline silicon film by a depth of 100 Å.