Structural and electrical investigation of MI2M and MI3M diodes for improved non-linear, low bias rectification. (August 2022)

• Record Type: Journal Article
• Authors: Nemr Noureddine, I.; Sedghi, N.; Wrench, J.S.; Mitrovic, I.Z.; Chalker, P.R.; Hall, S.
• Is Part Of: Solid-state electronics. Volume 194(2022)
• Publication Date: 2022-08
• Subjects: Multi-dielectric diode -- Native oxide -- Tunnelling -- Tsu-Esaki model -- Transfer matrix method -- WKB approximation -- THz rectification -- Rectenna; Semiconductors -- Periodicals; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.sse.2022.108349
• Languages: English
• ISSNs: 0038-1101

Abstract

Highlights: Band gap engineering is investigated focusing on experimental-to-model matching. Native oxide grown at interfaces with Al electrodes: assessed with structural imaging. Tunnelling mechanisms are assessed using transfer matrix and WKB methods. MI3 M/MI2 M fabricated: highly non-linear at turn-on voltages of 0.17/0.21 V. Active area minimisation: prospects for ultra high-speed applications towards THz. Abstract: Multi-stack metal–insulator-metal diodes devices of atomic layer deposited (ALD) and sputtered Ta2 O5 and Al2 O3 dielectrics with Au bottom electrode are investigated comprehensively by experiment and modelling. The layer structure is inspected - and the native contact metal oxide effects are incorporated in the modelling computation - using atomic force microscopy (AFM), spectroscopic ellipsometry, and transmission electron spectroscopy (TEM). The tunnelling transport is successfully modelled using both the transfer matrix (TMM) and Wentzel-Kramers-Brillouin (WKB) methods. Parasitic currents are identified using their voltage and temperature dependence. Rectification for a triple dielectric layer device is shown to occur at a turn-on voltage as low as 170 mV with a non-linearity of 3 and an asymmetry increasing from 2.2 at the turn-on voltage to over two orders of magnitude at 1 V.