Laser ablated pure non-crystalline Co thin films for inductors for ultra-high frequencies

摘要

Non-crystalline Co thin films have been prepared by pulsed laser ablation deposition. From the M-H hysteresis loops measurements, a soft magnetic behavior is observed. Neel type magnetic domain walls are observed in the as-deposited films. The spontaneous magnetization, M_s (T = 300 K), is ≈ 860 emu/cm~3. After annealing at 500℃, M_s (T = 300 K) is ≈ 1460 emu/cm~3. The extrapolated to zero K resistance decreases almost two orders of magnitude from the as deposited samples to the crystallized heated at 500℃ ones. A trilayer Co/Cu/Co has shown a real part magnetic susceptibility of 120 at 100 MHz. In the 100 MHz to 1 GHz frequency range, a perpendicular bias magnetic field increased this value up to 270, remaining almost constant for all range.