Improvement of Soft Magnetic Properties of Si/NiFe/FeCoB Thin Films at Gigahertz Band Frequency Range by Multilayer Configuration

FeCoHfN thin films fabricated by co-sputtering with high resonance frequency

“…The sample grown atˇ= 18 • clearly shows a more slanted hard axis curve than the sample grown atˇ= 0 • indicating that the magnetic anisotropy field in sample atˇ= 18 • is larger. This enhancement of uniaxial anisotropy field with the off-center of substrate position is similar to that observed in oblique deposition [5][6][7]15] and may be interpreted in the same way. It is generally accepted in the literature that the mechanism of the oblique incidence anisotropy is due to induced uniaxial stress anisotropy, a modification of the short range order and/or columnar growth morphology with increasing oblique angle [5,6].…”

“…Nowadays, as the operating frequency in many devices reaches gigahertz, for instance the typical frequencies for Bluetooth technology are 2.4 and 5.8 GHz, the need for magnetic thin films with high resonance frequency is indispensable [2,3]. Among various materials, thin films based on FeCo alloy such as FeCoN [1], FeCoB [5][6][7], FeCo-SiO 2 [2,8], FeCo-Al 2 O 3 [9], FeCo-SiN [10], FeCo-HfO [11] and FeCo-HfN [12,13] have received much attention due to their relatively high saturation magnetization. In this paper, we report the investigation of magnetic dynamic properties of FeCoHfN thin films grown by co-sputtering of FeCo and Hf.…”

An algorithm to extract effective magnetic parameters of thin film with in-plane uniaxial magnetic anisotropy

“…Figure 3 shows the first example of using the algorithm to obtain the magnetic parameters of Si/NiFe/FeCoB. 6. ͑7͒, the LL FMR model without skin effect, to simulate the curves shown in Fig.…”

“…6,7 It is also concluded that the consideration for skin depth effect is necessary for samples with low electrical resistivity, but it is not necessary if the electrical resistivity is high. LL FMR model with skin effect has been verified with other theoretical results 4 and the algorithm has been used to extract the effective M s , H k , and ␣ of Si/NiFe/FeCoB and CoZrRe.…”

Soft magnetic multilayer films with wide frequency band losses and high resistivity

“…FeCo‐based soft magnetic thin‐film materials have attracted much attention and are extensively investigated 6–8 due to their high 4 πM s , low coercivity ( H c ), and high permeability. A single FeCoB‐layer film with thickness of 200 nm showed a high resonance frequency of 6.4 GHz and stable µ ′ of 70 up to 3 GHz, low damping constant α and resistivity ρ 9. This is an ideal film for inductors and power‐conversion devices, but the development of integrated RF shielding requires wide frequency band losses and high resistivity.…”