Cubic-phase zirconia nano-island growth using atomic layer deposition and application in low-power charge-trapping nonvolatile-memory devices. (5th October 2017)

• Record Type: Journal Article
• Authors: El-Atab, Nazek; Gamze Ulusoy, Turkan; Ghobadi, Amir; Suh, Junkyo; Islam, Raisul; Okyay, Ali K; Saraswat, Krishna; Nayfeh, Ammar
• Is Part Of: Nanotechnology. Volume 28:Number 44(2017)
• Publication Date: 2017-10-05
• Subjects: zirconia -- atomic layer deposition -- memory devices; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/aa87e5
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: The manipulation of matter at the nanoscale enables the generation of properties in a material that would otherwise be challenging or impossible to realize in the bulk state. Here, we demonstrate growth of zirconia nano-islands using atomic layer deposition on different substrate terminations. Transmission electron microscopy and Raman measurements indicate that the nano-islands consist of nano-crystallites of the cubic-crystalline phase, which results in a higher dielectric constant ( κ ∼ 35) than the amorphous phase case ( κ ∼ 20). X-ray photoelectron spectroscopy measurements show that a deep quantum well is formed in the Al2 O3 /ZrO2 /Al2 O3 system, which is substantially different to that in the bulk state of zirconia and is more favorable for memory application. Finally, a memory device with a ZrO2 nano-island charge-trapping layer is fabricated, and a wide memory window of 4.5 V is obtained at a low programming voltage of 5 V due to the large dielectric constant of the islands in addition to excellent endurance and retention characteristics.