High-power pulsed magnetron sputtering （HPPMS or HiPIMS） is an emerging coating technology that produces very dense plasmas and highly ionized sputtering atoms. This paper is focused on discharge properties, unbalan...High-power pulsed magnetron sputtering （HPPMS or HiPIMS） is an emerging coating technology that produces very dense plasmas and highly ionized sputtering atoms. This paper is focused on discharge properties, unbalanced features and temporal evolution of pulse current of the HPPMS discharge. A hollow cathode was used to suppress the scattering of charges. A coaxial coil surrounding the target was used to control the breakdownvoltage and pulse repetition frequency by varying the coil current. A Langmuir probe and an oscilloscope were used to simultaneously measure the floating potential, pulse voltage and pulse current signMs. The pulse power density in the discharge reached 10 kW/cm2 with frequencies as high as N40 Hz and a pulse width about 1~5 ms. The characteristics of the discharge evolution were analyzed using magnetron discharge dynamics.展开更多
Yttrium iron garnet(YIG) films possessing both perpendicular magnetic anisotropy(PMA) and low damping would serve as ideal candidates for high-speed energy-efficient spintronic and magnonic devices.However,it is still...Yttrium iron garnet(YIG) films possessing both perpendicular magnetic anisotropy(PMA) and low damping would serve as ideal candidates for high-speed energy-efficient spintronic and magnonic devices.However,it is still challenging to achieve PMA in YIG films thicker than 20 nm,which is a major bottleneck for their development.In this work,we demonstrate that this problem can be solved by using substrates with moderate lattice mismatch with YIG so as to suppress the excessive strain-induced stress release as increasing the YIG thickness.After carefully optimizing the growth and annealing conditions,we have achieved out-of-plane spontaneous magnetization in YIG films grown on sGGG substrates,even when they are as thick as 50 nm.Furthermore,ferromagnetic resonance and spin pumping induced inverse spin Hall effect measurements further verify the good spin transparency at the surface of our YIG films.展开更多
基金supported by National Natural Science Foundation of China(No.50407015)the Scientific Research Fund of the Liaoning Provincial Education Department of China
文摘High-power pulsed magnetron sputtering （HPPMS or HiPIMS） is an emerging coating technology that produces very dense plasmas and highly ionized sputtering atoms. This paper is focused on discharge properties, unbalanced features and temporal evolution of pulse current of the HPPMS discharge. A hollow cathode was used to suppress the scattering of charges. A coaxial coil surrounding the target was used to control the breakdownvoltage and pulse repetition frequency by varying the coil current. A Langmuir probe and an oscilloscope were used to simultaneously measure the floating potential, pulse voltage and pulse current signMs. The pulse power density in the discharge reached 10 kW/cm2 with frequencies as high as N40 Hz and a pulse width about 1~5 ms. The characteristics of the discharge evolution were analyzed using magnetron discharge dynamics.
基金supported by the National Natural Science Foundation of China(Grant Nos.52072060 and 52021001)the National Key R&D Program of China(Grant No.2021YFB2801600)the China Postdoctoral Science Foundation(Grant No.2021M700679)。
文摘Yttrium iron garnet(YIG) films possessing both perpendicular magnetic anisotropy(PMA) and low damping would serve as ideal candidates for high-speed energy-efficient spintronic and magnonic devices.However,it is still challenging to achieve PMA in YIG films thicker than 20 nm,which is a major bottleneck for their development.In this work,we demonstrate that this problem can be solved by using substrates with moderate lattice mismatch with YIG so as to suppress the excessive strain-induced stress release as increasing the YIG thickness.After carefully optimizing the growth and annealing conditions,we have achieved out-of-plane spontaneous magnetization in YIG films grown on sGGG substrates,even when they are as thick as 50 nm.Furthermore,ferromagnetic resonance and spin pumping induced inverse spin Hall effect measurements further verify the good spin transparency at the surface of our YIG films.
