Optimization of sputter deposition parameters for magnetostrictive Fe62Co19Ga19/Si(100) films

Abstract

A good magnetostrictive material should have large saturation magnetostriction (λS) and low saturation (or anisotropy) field (HS), such that its magnetostriction susceptibility (SH) can be as large as possible. In this study, we have made Fe62Co19Ga19/Si(100) nano-crystalline films by using the dc magnetron sputtering technique under various deposition conditions: Ar working gas pressure (pAr) was varied from 1 to 15 mTorr; sputtering power (Pw) was from 10 to 120 W; deposition temperature (TS) was from room temperature (RT) to 300 °C, The film thickness (tf) was fixed at 175 nm. Each magnetic domain looked like a long leaf, with a long-axis of about 12–15 μm and a short-axis of about 1.5 μm. The optimal magnetic and electrical properties were found from the Fe62Co19Ga19 film made with the sputter deposition parameters of pAr = 5 mTorr, Pw = 80 W, and TS = RT. Those optimal properties include λS = 80 ppm, HS = 19.8 Oe, SH = 6.1 ppm/Oe, and electrical resistivity ρ = 57.0 μΩ cm. Note that SH for the conventional magnetostrictive Terfenol-D film is, in general, equal to 1.5 ppm/Oe only.

Effect of the Sputtering Power on the Structure, Morphology and Magnetic Properties of Fe Films

“…The sputtering power can affect the growth rate and film thickness of Mo film, thereby affecting the electrical properties of the film [36]. Adjusting the sputtering power can optimize the magnetostrictive properties of Fe 62 Co 19 Ga 19 thin films [37]. This research work indicates that it is necessary to carry out the influence of the sputtering power on the structure, morphology and magnetic properties of the iron thin film.…”

Structural, magneto-mechanical, and damping properties of slowly-cooled polycrystalline Fe 81 Ga 19 alloy

“…The excitation voltage was 0.01 V and the frequency (f) range was from 20 to 4 Â 10 5 Hz. Because the strip sample alone forms a magnetic open circuit, the relation between the measured permeability (m a ) and m R at low f is expressed as (1/ m a ) ¼ (1/m R ) þ N d , where N d is the demagnetizing factor along length [13]. In order to avoid the N d complexity, we had both ends of the strip be mechanically connected to a U shape yoke, made of (99.99%) pure Fe.…”