Control of Microstructure, Trap Levels, and Trap Distribution in HfO 2 Films Grown by Atomic Layer Deposition.
Saved in:
| Title: | Control of Microstructure, Trap Levels, and Trap Distribution in HfO 2 Films Grown by Atomic Layer Deposition. |
|---|---|
| Authors: | Sharafi, Seyedeh Mahsa1 (AUTHOR), Flores, Marco2 (AUTHOR), Appuhami, Himasha3 (AUTHOR), Selim, Farida A.1,3 (AUTHOR) farida.selim@asu.edu |
| Source: | Nanomaterials (2079-4991). Apr2026, Vol. 16 Issue 8, p451. 19p. |
| Subjects: | Hafnium oxide films, Electron traps, X-ray diffraction, Dielectric properties, Atomic layer deposition, Electron paramagnetic resonance, Nanostructured materials |
| Abstract: | HfO2 films have become a critical component for advanced electronics and a wide range of applications. However, their implementation requires control of their microstructure and defects, which often act as charge carrier traps, leading to leakage current in devices and hindering their dielectric properties. Here, we deposit HfO2 thin films by atomic layer deposition (ALD) on sapphire, Ga2O3, and InGaO3 substrates at low temperature and investigate the dependence of their crystal structure on substrate type, annealing, and thickness. X-ray diffraction measurements showed that alloying Ga2O3 with a modest amount of Indium transferred HfO2 films from amorphous to polycrystalline, an important finding that may be applicable to the deposition of other material systems. The study also presents an interesting approach to measuring shallow and deep traps formed in the films and shows how to control their levels and distributions in the band gap. The measurements reveal that the difference in band gap between the substrate and film, as well as the presence of impurities, strongly influences trap densities and depths. Electron paramagnetic resonance (EPR) measurements were performed to probe the electronic structure of specific point defects detectable by EPR and to correlate these results with trap measurements. [ABSTRACT FROM AUTHOR] |
| Copyright of Nanomaterials (2079-4991) is the property of MDPI and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) | |
| Database: | Engineering Source |
|
Full text is not displayed to guests.
Login for full access.
|
|
| Abstract: | HfO2 films have become a critical component for advanced electronics and a wide range of applications. However, their implementation requires control of their microstructure and defects, which often act as charge carrier traps, leading to leakage current in devices and hindering their dielectric properties. Here, we deposit HfO2 thin films by atomic layer deposition (ALD) on sapphire, Ga2O3, and InGaO3 substrates at low temperature and investigate the dependence of their crystal structure on substrate type, annealing, and thickness. X-ray diffraction measurements showed that alloying Ga2O3 with a modest amount of Indium transferred HfO2 films from amorphous to polycrystalline, an important finding that may be applicable to the deposition of other material systems. The study also presents an interesting approach to measuring shallow and deep traps formed in the films and shows how to control their levels and distributions in the band gap. The measurements reveal that the difference in band gap between the substrate and film, as well as the presence of impurities, strongly influences trap densities and depths. Electron paramagnetic resonance (EPR) measurements were performed to probe the electronic structure of specific point defects detectable by EPR and to correlate these results with trap measurements. [ABSTRACT FROM AUTHOR] |
|---|---|
| ISSN: | 20794991 |
| DOI: | 10.3390/nano16080451 |
