The planar anodic Al2O3-ZrO2 nanocomposite capacitor dielectrics for advanced passive device integration

Kirill Kamnev; Zdenek Pytlicek; Maria Bendova; Jan Prasek; Francesc Gispert-Guirado; Eduard Llobet; Alexander Mozalev

doi:10.1080/14686996.2022.2162324

The planar anodic Al₂O₃-ZrO₂ nanocomposite capacitor dielectrics for advanced passive device integration

Sci Technol Adv Mater. 2023 Feb 13;24(1):2162324. doi: 10.1080/14686996.2022.2162324. eCollection 2023.

Authors

Kirill Kamnev¹, Zdenek Pytlicek¹, Maria Bendova¹, Jan Prasek^{1

2}, Francesc Gispert-Guirado³, Eduard Llobet⁴, Alexander Mozalev^{1

2}

Affiliations

¹ CEITEC - Central European Institute of Technology, Brno University of Technology, Brno, Czech Republic.
² Department of Microelectronics, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic.
³ SRCiT, University Rovira i Virgili, Tarragona, Spain.
⁴ MINOS-EMaS, University Rovira i Virgili, Tarragona, Spain.

Abstract

The need for integrated passive devices (IPDs) emerges from the increasing consumer demand for electronic product miniaturization. Metal-insulator-metal (MIM) capacitors are vital components of IPD systems. Developing new materials and technologies is essential for advancing capacitor characteristics and co-integrating with other electronic passives. Here we present an innovative electrochemical technology joined with the sputter-deposition of Al and Zr layers to synthesize novel planar nanocomposite metal-oxide dielectrics consisting of ZrO₂ nanorods self-embedded into the nanoporous Al₂O₃ matrix such that its pores are entirely filled with zirconium oxide. The technology is utilized in MIM capacitors characterized by modern surface and interface analysis techniques and electrical measurements. In the 95-480 nm thickness range, the best-achieved MIM device characteristics are the one-layer capacitance density of 112 nF·cm^-2, the loss tangent of 4·10^-3 at frequencies up to 1 MHz, the leakage current density of 40 pA·cm^-2, the breakdown field strength of up to 10 MV·cm^-1, the energy density of 100 J·cm^-3, the quadratic voltage coefficient of capacitance of 4 ppm·V^-2, and the temperature coefficient of capacitance of 480 ppm·K^-1 at 293-423 K at 1 MHz. The outstanding performance, stability, and tunable capacitors' characteristics allow for their application in low-pass filters, coupling/decoupling/bypass circuits, RC oscillators, energy-storage devices, ultrafast charge/discharge units, or high-precision analog-to-digital converters. The capacitor technology based on the non-porous planar anodic-oxide dielectrics complements the electrochemical conception of IPDs that combined, until now, the anodized aluminum interconnection, microresistors, and microinductors, all co-related in one system for use in portable electronic devices.

Keywords: Al2O3-ZrO2; Anodizing; MIM capacitors; dielectric; integrated passives; nanocomposite films; porous anodic alumina.

Grants and funding

This research was supported by a grant from the Czech Science Foundation (GA ČR) no. 20-25486S. CzechNanoLab project [LM2018110] funded by MEYS CR is acknowledged for the financial support of silicon wafer oxidation, magnetron sputter-deposition, SEM, and electric/dielectric measurements at CEITEC Nano Research Infrastructure. EL was supported by the Catalan Institution for Research and Advanced Studies via the 2018 Edition of the ICREA Academia Award.