US 11,856,790 B2
Ferroelectric capacitors
Ashonita A. Chavan, Boise, ID (US); Durai Vishak Nirmal Ramaswamy, Boise, ID (US); and Manuj Nahar, Boise, ID (US)
Assigned to Micron Technology, Inc., Boise, ID (US)
Filed by Micron Technology, Inc., Boise, ID (US)
Filed on Nov. 30, 2022, as Appl. No. 18/072,546.
Application 18/072,546 is a division of application No. 16/989,218, filed on Aug. 10, 2020, granted, now 11,552,086.
Application 15/840,251 is a division of application No. 14/958,182, filed on Dec. 3, 2015, granted, now 9,876,018, issued on Jan. 23, 2018.
Application 16/989,218 is a continuation of application No. 15/840,251, filed on Dec. 13, 2017, granted, now 10,748,914, issued on Aug. 18, 2020.
Prior Publication US 2023/0121892 A1, Apr. 20, 2023
Int. Cl. H01L 29/78 (2006.01); H10B 53/30 (2023.01); H01L 21/28 (2006.01); H10B 51/30 (2023.01); H01L 21/02 (2006.01); H01L 49/02 (2006.01); H01L 29/49 (2006.01); H01L 29/51 (2006.01); H01L 29/66 (2006.01)
CPC H10B 53/30 (2023.02) [H01L 21/02164 (2013.01); H01L 21/28088 (2013.01); H01L 21/28097 (2013.01); H01L 28/55 (2013.01); H01L 28/60 (2013.01); H01L 29/40111 (2019.08); H01L 29/4966 (2013.01); H01L 29/4975 (2013.01); H01L 29/516 (2013.01); H01L 29/517 (2013.01); H01L 29/6684 (2013.01); H01L 29/78391 (2014.09); H10B 51/30 (2023.02)] 9 Claims
OG exemplary drawing
 
1. A ferroelectric field effect transistor, comprising:
a pair of source/drain regions having a semiconductive channel therebetween; and
a gate structure comprising:
a ferroelectric gate insulator material comprising one or more members of the group consisting of zirconium, zirconium oxide, hafnium, hafnium oxide, lead zirconium titanate, tantalum oxide, strontium oxide, and strontium titanium oxide;
a conductive gate electrode; and
a composite stack comprising at least two non-ferroelectric metal oxide compositions, the composite stack having three or more discrete layers including a first layer, a second layer and a third layer with the second layer being in direct physical contact with the first and third layers and with at least one of the layers comprised by the composite stack containing a metal oxide selected from the group consisting of ScOx, Sc2O3, YOx, Y2O3, MgOx, MgO, SrOx, SrO, NbOx, GdOx, MoOx, RuOx, LaOx, VxOy, IrOx, CrOx, ZnOx, PrOx, CeOx, SmOx, and LuOx, the composite stack having an overall conductivity that is less than a conductivity of the conductive gate electrode.