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MRAM is a non-volatile memory which stores its data in the spin degree of freedom and provides a promising alternative to the current charge-based memories which are starting to hit the fundamental limits of scaling. The core element of MRAM is the magnetic tunnel junction (MTJ) which encodes binary bits in the relative alignment of the free layer with respect to the reference layer. Spin torque-induced magnetization reversal of the free layer promises efficient switching of the MRAM bit state which is scalable towards smaller dimensions. STT-MRAM uses the spin-transfer torque (STT) phenomenon to influence the state of an MRAM cell upon the injection of a perpendicular current, whereas SOT-MRAM utilizes a spin-orbit torque (SOT) originating from a heavy metal layer below the free layer upon the injection of an in-plane current. However, both of these writing schemes have drawbacks with STT-MRAM not being able to reach the switching speeds required to replace the lower level cache memories in addition to issues of reliability. Conversely, SOT-MRAM provides very fast switching, while also solving the reliability issues of STT due to the decoupling of read and write path, however, it has the significant drawback as it requires an external field in order to break the inherent symmetry of the reversal. The hybrid switching under investigation in this thesis uses the complementary nature of SOT and STT in order to achieve very fast field-free switching by combining both torques to switch the state of the MRAM. Additionally, thermal fluctuations can negatively impact the data retention of the MRAM with thermal stability increasingly becoming an issue for smaller MRAM cell size. The move to perpendicularly magnetized MTJs granted a degree of respite, however, further scaling requires novel solutions. The synthetic antiferromagnet hybrid free layer (SAF-HFL) increases the complexity of the system by introducing a new exchange coupling torque, but can enable further scaling of the device dimensions while maintaining thermal stability. Field-free switching has been achieved in this thesis using the hybrdid switching scheme in both the single free layer and the SAF-HFL while the results provide a better understanding of the role of each torque and their competition with each other.