Post-Deposition Annealing Effects on Ferromagnetic CoFeB Thin Films (Postprint)
Abstract
We investigate the role of annealing Co40Fe40B20 at different temperatures and how it affects the crystallinity and the ferromagnetic resonance (FMR) behavior. The onset of crystallization was shown to occur after annealing in nitrogen at 370 C for 1 h. The crystallization peak of the post-annealed Co40Fe40B20 was matched to the analysis of (110) Co7Fe3, due to secondary phase segregation. Magnetic force microscopy images show a pattern of magnetization ripples in the magnetic phase images for samples up to 250 C. The grain size of the Co7Fe3 (110) was shown to increase from 20 to 56 nm when annealed above 370 C to 600 C. The segregated Co7Fe3 causes scattering of the FMR linewidth, which shifts the resonance peak location, broadens peak-to-peak linewidth, and causes an additional resonance peak to appear close to the uniform resonance of the amorphous phase. Annealing above 500 C leads to a complete phase change to Co7Fe3, which changes the FMR spectra back to a single resonance peak, shifted to lower elds with broader peak-to-peak linewidth of 71.2 (kA/m).
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 17, 2018
- Accession Number
- AD1064432
Entities
People
- Adam B. Phillips
- Daniel G. Georgiev
- Gail J. Brown
- John G Jones
- Michael J. Heben
- Ryan A. O'dell
Organizations
- University of Toledo