Leuven | More than two weeks ago
Conventional CMOS technology has now become challenging to continuously shrink down due to the reduced transistor dimensions, while also keeping the power budget constant and increasing device performance. The fundamental limitation of such charge-based devices is the leakage current at low dimensions, resulting in more power consumption. To circumvent these dimensional scaling issues, Beyond-CMOS technologies based on spintronics devices are increasingly explored to enable more functionalities in a single device for new computing architectures.
Spin logic devices based on magnetic domain walls (DWs, i.e., the boundary between two magnetic domains with different magnetization directions) motion is one of the potential candidates for Beyond CMOS. In such a device, the logic information is encoded in a magnetic domain while the motion of domain wall is employed to perform the logic operation. Recently, a full logic circuit based on DW motion has been experimentally demonstrated . This proof of concept is an important step towards DW-based logic devices, but their demonstration still misses the write/read components to electrically control the logic states in a nanoscale device. This would be a key factor that impedes to bring such DW logic devices closer to the practical application. At imec, we recently demonstrated a full electrical operation of a basic building block of a nanoscale DW device on 300 mm wafer with magnetic tunnel junctions (MTJ, i.e., a magnetic heterostructure in which an oxide tunneling barrier is sandwiched by two ferromagnetic layers known as a storage and a pinned layer) as read/write components [2, 3]. Therefore, a combination of these demonstrations in a single DW logic device holds promise for practical implementation of nanoscale DW logic devices.
The goal of this internship is to focus on exploratory simulations of DW logic devices where MTJ is implemented as write/read components while spin orbit torque is used to drive DW motion for logic operation in a logic circuit. This project will involve different aspects for physical understanding the logic operation from electrical writing of DW via MTJs at the logic inputs to the dynamics of DW motion in a DW logic circuit. By micromagnetic simulation (OOMMF, MuMax, etc.), the student will first explore the impact of MTJ properties on the switching efficiency for electrical writing of the DW at the logic inputs. The student will then study different device geometries to enable logic operation and focus on physical understanding of the dynamics of DW motion during the operation of logic devices. The results of this study will inform and guide the experimental setup towards a full electrical control of nanoscale DW logic devices on 300 mm wafer.
1. Luo, et al. Current-driven magnetic domain-wall logic. Nature 579, 214–218 (2020).
2. Raymenants et al., Nanoscale domain wall devices with magnetic tunnel junction read and write, Nat. Elec. 4, 392 (2021).
Type of project: Combination of internship and thesis
Duration: At least 6 months
Required degree: Master of Science, Master of Engineering Technology
Required background: Nanoscience & Nanotechnology, Physics