Skip to main content
Research article - Peer-reviewed, 2021

Hexacoordinated Gallium(III) Triazenide Precursor for Epitaxial Gallium Nitride by Atomic Layer Deposition

Rouf, Polla; Samii, Rouzbeh; Ronnby, Karl; Bakhit, Babak; Buttera, Sydney C.; Martinovic, Ivan; Ojamae, Lars; Hsu, Chih-Wei; Palisaitis, Justinas; Kessler, Vadim; Pedersen, Henrik; O'Brien, Nathan J.

Abstract

Gallium nitride (GaN) is the main component of modern-day high electron mobility transistors due to its favorable electronic properties. As electronic devices become smaller with more complex surface architecture, the ability to deposit high-quality GaN films at low temperatures is required. Herein, we report a new highly volatile Ga(III) triazenide precursor and demonstrate its ability to deposit high-quality epitaxial GaN by atomic layer deposition (ALD). This new Ga(III) triazenide, the first hexacoordinated Ga-N bonded precursor used in a vapor deposition process, was easily synthesized and purified by either sublimation or recrystallisation. Thermogravimetric analysis showed single-step volatilization with an onset temperature of 155 degrees C and negligible residual mass. Three temperature intervals with self-limiting growth were observed when depositing GaN films. The GaN films grown in the second growth interval at 350 degrees C were epitaxial on 4H-SiC without an AlN seed layer and found to have a near stoichiometric Ga/N ratio with very low levels of impurities. In addition, electron microstructure analysis showed a smooth film surface and a sharp interface between the substrate and film. The band gap of these films was 3.41 eV with the Fermi level at 1.90 eV, showing that the GaN films were unintentionally n-type-doped. This new triazenide precursor enables ALD of GaN for semiconductor applications and provides a new Ga(III) precursor for future deposition processes.

Published in

Chemistry of Materials
2021, volume: 33, number: 9, pages: 3266-3275
Publisher: AMER CHEMICAL SOC

Authors' information

Rouf, Polla
Linkoping University
Samii, Rouzbeh
Linkoping University
Ronnby, Karl
Linkoping University
Bakhit, Babak
Linkoping University
Buttera, Sydney C.
Carleton University
Martinovic, Ivan
Linkoping University
Ojamae, Lars
Linkoping University
Hsu, Chih-Wei
Linkoping University
Palisaitis, Justinas
Linkoping University
Swedish University of Agricultural Sciences, Department of Molecular Sciences
Pedersen, Henrik
Linkoping University
O'Brien, Nathan J.
Linkoping University

UKÄ Subject classification

Materials Chemistry

Publication Identifiers

DOI: https://doi.org/10.1021/acs.chemmater.1c00244

URI (permanent link to this page)

https://res.slu.se/id/publ/112452