Spin wave emission by spin transfer torque for beyond CMOS logic application

Spin wave devices are a promising alternative to realize logic circuits based on wave computing. The field is referred also as Magnonics. Spin waves (and their quanta: magnons) are used to transmit, and process signals in magnetic waveguides and the logic functions are performed by wave interference. The low power consumption and the possibility to scale down the are of the logic function have drawn significant interest in this field. To be integrated with CMOS technology, spin wave devices require efficient transducers to emit and detect magnons with an electrical current or voltage. It has been shown that transducers based on spin-transfer torque (STT) emission could be potential candidates. This experimental thesis consisted in the study of material and devices towards efficient spin wave emission by STT. Specific orthogonal magnetic tunnel junction stacks have been prepared, and their static and dynamic properties have been characterized at blanket and device level. Process development has been additionally completed to fabricate devices for spin wave excitation via STT. This thesis was performed at IMEC facilities in Leuven, an international research center active in the fields of nanoelectronics.