A team led by National Tsing Hua University (NTHU) professors yesterday announced a breakthrough in magnetic random access memory (MRAM) semiconductor research.
MRAM is considered a better memory device than dynamic random access memory (DRAM) and static random access memory (SRAM), as it is faster and more energy-efficient, and its stored information remains intact even when it is powered down, NTHU Department of Materials Science and Engineering professor Lai Chih-huang (賴志煌) said.
MRAM works by manipulating its ferromagnetic and antiferromagnetic layers (classes of magnetic materials), but researchers have been working to make the manipulation more flexible, without having to change the MRAM’s external temperature, Lai said.
Photo: Chien Hui-ju, Taipei Times
After adding a platinum layer under the ferromagnetic and antiferromagnetic layers, the team succeeded in using a spin current caused by the flow of electrons to manipulate their “exchange bias,” a phenomenon occurring in magnetic multilayers where the antiferromagnetic layer “fixes” the ferromagnetic layer, he said.
The team is the world’s first to use a spin current to manipulate the exchange bias, resolving an obstacle that researchers have battled with for the past 60 years, he said.
Understanding spin current is vital for semiconductor development, as it has been pushed to the extreme, he said.
The team patented the technique in Taiwan, the US and China before publishing their findings in a paper titled “Manipulating exchange bias by spin-orbit torque” in the journal Nature Materials on Feb. 18, Lai said.
To verify their experiments, the team also developed techniques to measure temperature variations in microseconds, NTHU Department of Physics professor Lin Hsiu-hau (林秀豪) said.
While most scientists are still debating whether a spin current can manipulate the switching of micromagnets beyond 1 nanometer, the team has demonstrated that manipulations caused by a spin current can persist for more than several nanometers, Lin said.
After submitting their manuscript to the journal, the team spent more than one year convincing the journal’s reviewers that it was a Taiwanese team who achieved the breakthrough, despite limited funding, he added.
Funded by the Ministry of Science and Technology, the team also works with the ministry’s Taiwan Semiconductor Research Institute and other universities, Lai said.
Their technique might be used in the mass production of new MRAM devices in four or five years, Lai said, adding that they are meeting with domestic semiconductor firms to discuss a technology transfer.
LIABILITIES MULLED: New Taipei City Mayor Hou You-yi said Taipei would find out if the firm was legally registered, the guide was licensed and the weather was assessed The assets of Tian Da Local Nature Co are to be frozen after at least four people died after falling into the Beishi River (北勢溪) on an outing the company had organized on Saturday, the Taipei City Government said yesterday. Six people — two adults and four children — were washed away by a flash flood on the river in New Taipei City’s Hubaotan (虎豹潭) area. They were participating in a Nature Joy Camp outdoor activity with a group of 16 adults and 15 children led by a guide surnamed Su (蘇). As of 4:30pm yesterday, four of the missing had been
Taiwanese worked more hours than people in all but three other countries in the world last year, Ministry of Labor data showed. Singapore placed first in average hours worked among the 40 economies surveyed, with an average of 2,288 hours per worker last year, the data showed. The city-state was followed by Colombia with 2,172 hours — based on 2019 data — and Mexico with 2,124 hours, it showed. Taiwan came in fourth, with 2,021 hours, it showed. South Korean workers clocked the third-most hours in Asia, with 1,908 hours, followed by Japan with 1,598 hours, it showed. However, compared with 2019, the survey found
The US 7th Fleet yesterday confirmed that a US Navy ship transited the Taiwan Strait on Thursday and Friday. “The Arleigh Burke-class guided missile destroyer USS Dewey [DDG 105] conducted a Taiwan Strait transit in cooperation with Royal Canadian Navy [RCN] Halifax-class frigate, HMCS Winnipeg, October 14-15, 2021,” the US 7th Fleet said in a statement. “Dewey’s and Winnipeg’s transit through the Taiwan Strait demonstrates the commitment of the United States and our allies and partners to a free and open Indo-Pacific. Cooperation like this represents the centerpiece of our approach to a secure and prosperous region,” it added. The transit marked the
‘COUNTERPRODUCTIVE’: The German, French and Singaporean missions said that Taiwan’s COVID-19 restrictions are hindering local projects and business operations Several foreign missions in Taiwan have urged the government to ease its strict COVID-19 border controls, which they say are hurting in-person exchanges and business operations. The missions made the appeal in response to media inquiries on how the border controls have affected their respective countries’ exchanges with Taiwan, amid growing concerns voiced privately by Taiwan-based foreign offices and businesses regarding the restrictions. Taiwan has maintained strict entry requirements since March last year, generally prohibiting most arrivals except for citizens and foreign residents, while it has required those who enter the country to undergo a stringent 14-day quarantine. Although the rules have been
RSS