Effects of substrate bias and annealing on the properties of amorphous alloy films of Gd-Co, Gd-Fe, and Gd-Co-X (X=Mo,Cu,Au)

Journal Article · Sun Jan 01 04:00:00 EST 1978 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.324344· OSTI ID:5192819

Heiman, N; Kazama, N; Kyser, D F; Minkiewicz, V J

We have examined the dependence of various properties of sputter-deposited amorphous GdCo, GdFe, and GdCoX (X=Mo,Cu,Au) films upon substrate bias and annealing. Particular interest was directed to changes in magnetization, anisotropy, composition, x-ray diffraction patterns, and Ar content of the films. In the case of the binary films, we applied substrate bias voltages to 400 V. We found that for the GdCo system, K/sub u/ rises with increasingly negative bias voltage to about V/sub b/=-200 V. Further increases in V/sub b/ cause K/sub u/ to decrease, so that K/sub u/approx. =0 for V/sub b/approx. =-400 V. Furthermore, it was found that the Ar content of the films tends to correlate with V/sub b/, reaching a maximum for V/sub b/approx. =-200 V. X-ray diffraction patterns of these films also appear to correlate with K/sub u/ but in a more subtle manner than has been suggested by other workers. The results for amorphous GdFe films were considerably different. In particular, it was found that K/sub u/ was large for V/sub b/> or =0 but decreased rapidly with negative bias. The behavior of ternary GdCoX films was similar to that of the binary GdCo films, except that the x-ray diffraction patterns showed little dependence on V/sub b/. On being annealed for 4 h at 200 /sup 0/C, the binary films show no change in magnetization, composition, or x-ray diffraction profile, but do experience a decrease in K/sub u/ by about a factor of 2. The situation is similar for the GdCoCu and GdCoAu films except that the temperature dependence of the magnetization also changes dramatically. In contrast to these results, amorphous GdCoMo films undergo little or no change on annealing. Our results suggest that the incorporation of Ar into the films is closely related to the mechanism responsible for K/sub u/ in these materials; however, there exist data which conflict with this interpretation, so that the origin of K/sub u/ remains in doubt.

• Research Organization: IBM Research Laboratory, San Jose, California 95193
• OSTI ID: 5192819
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 49:1; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ALLOYS
AMORPHOUS STATE
ANISOTROPY
ANNEALING
ARGON
CHEMICAL COMPOSITION
COBALT ALLOYS
COHERENT SCATTERING
COPPER ALLOYS
DIFFRACTION
ELEMENTS
FILMS
GADOLINIUM ALLOYS
GOLD ALLOYS
HEAT TREATMENTS
IRON ALLOYS
MAGNETIC PROPERTIES
MAGNETIZATION
MOLYBDENUM ALLOYS
NONMETALS
PHYSICAL PROPERTIES
RARE EARTH ALLOYS
RARE GASES
SCATTERING
TEMPERATURE DEPENDENCE
X-RAY DIFFRACTION