Technical / Research

Researchers from Northwestern University, led by Prof. Pedram Khalili, report the first all-antiferromagnetic tunnel junction (ATJ) devices with both electrical switching and electrical readout of the antiferromagnetic state. The researchers observed a large room-temperature tunneling magnetoresistance effect that is comparable in size to conventional ferromagnet-based tunnel junctions. 

To create the new devices, the researchers used sputtering to deposit the device films on conventional silicon wafers. The films are compatible with established semiconductor manufacturing processes. 

Renesas Electronics announced that it has developed circuit technologies for embedded STT-MRAM that reduces the energy and voltage of the memory write operation. 

Renesas produced a 22-nm MCU test chip, that includes a 10.8 Mbit embedded MRAM memory cell array. It achieves a random read access frequency of over 200 MHz and a write throughput of 10.4-megabytes-per-second (MB/s).

Researchers from Japan's Tohoku University developed a method to produce X nm MTJs, using a CoFeB/MgO stack structure. The researchers report that the extremely small device achieves both high-retention and high-speed. This was enabled by controlling the shape and interfacial anisotropies individually by varying the thickness of each CoFeB layer and the quantity of [CoFeB/MgO] stacks.

The researcher further report that shape anisotropy-enhanced MTJs showed good retention (> 10 years) at 150 °C at single nanometer sizes, whereas interfacial anisotropy-enhanced MTJs exhibited rapid speed switching (10 ns or less) below 1 V.

In 2022, Taiwan's Industrial Technology Research Institute (ITRI) announced an agreement with Taiwan Semiconductor Manufacturing Company (TSMC) to collaborate on SOT-MRAM R&D. ITRI and TSMC now announced that they have developed SOT-MRAM array chips that boasts a power consumption of merely one percent of a comparable STT-MRAM device. 

ITRI and TSMC published a new research paper that was presented at the 2023 IEE International Electron Devices Meeting (IEDM 2023). ITRI explains that the new unit cell achieves simultaneous low power consumption and high-speed operation, reaching speeds as rapid as 10 nanoseconds. And its overall computing performance can be further enhanced when integrated with computing in memory circuit design. 

US-based design house and services provider Green Mountain Semiconductor (GMS) has won a Phase I Small Business Innovation Research (SBIR) contract from NASA, to develop a neuromorphic AI processor for space applications using MRAM magnetic memory.

GMS's approach involves the development of an analysis tool to optimize circuit designs for reliability and radiation resistance. This advancement will enable the use of off-the-shelf technology in space applications without the need for excessive design modifications to ensure radiation resistance.

Researchers from the Tokyo Institute of Technology have successfully demonstrated fast p-MTJ switching (1 ns, compared to current switching that is >10 ns). "The researchers achieved this using the topological insulator BiSb as the SOT layer, and say the device offers a current density about 20 times smaller than typical.

The researchers say that this technology can be applied to develop p-MTJs for SOT-MRAM that will offer ultrafast operations and ultra low power consumption, while also offering higher reliability. This follows earlier work by the same group on BiSb p-MTJs.

Researchers from the Hebrew University of Jerusalem in Israel have made a recent discovery that could change the face of spintronics research - the most important equation used to describe magnetization dynamics, namely the Landau-Lifshitz-Gilbert (LLG) equation, also applies to the optical domain. 

A spintronics device developed by Professor Capua's lab

The new discovery has relevant applications in optical magnetic recording, namely in optically-controlled MRAM technology. Manipulation of the magnetization order parameter on optical timescales is key for ultrafast spintronics, which allows for faster, energy-efficient optically-controlled MRAM technology.

Researchers from the School of Engineering at Stanford University discovered that a metallic compound called manganese palladium three MnPd3 is a promising material to build SOT-MRAM memory devices. 

The researchers say that the new material enables a breakthrough in SOT-MRAM device performance, as it is the first material that generates spin in the z-direction, rather than the y-direction as in most materials, which is a property needed in high-performance SOT-MRAM. In fact MnPd3 is able to generate spins in any orientation because its internal structure lacks the kind of crystal symmetry that would force all of the electrons into a particular orientation.

Hprobe, a developer of testing equipment for magnetic devices, announced a new addition to its product line, the RF Pulse Module. The company says that this is the commercially available testing system to both collect statistics of error rate of the memory unit cell and take a deep look into switching dynamics of resistive memories.

Hprobe's IBEX system

Hprobe says that the RF Pulse Module is two orders of magnitude faster than existing devices and can help increase manufacturing yields. Hprobe has already begun shipping to tier-1 companies and major research institutes around the world.

A research team from Northwestern Engineering, led by Prof. Pedram Khalili developed highly efficiency nanoscale perpendicular MRAM (pMTJ) devices that use sub-volt switching. The researcher say that this new technology can allow scaling MRAM to very high densities.

The new devices are referred to as voltage-controlled MRAM (VCM), that does not rely on current like regular MRAM devices. Most VCM devices need high switching voltage (at least 2 volts), but by using a new material structure with significantly higher sensitivity of the magnetic properties to voltage, the researchers were able to operate at less than one volt.