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.
NEW AGREEMENT: Malaysia approved imports last year after nearly two years of negotiations and inspections to meet quarantine requirements, officials said Up to 3.6 tonnes of pomeloes from Taiwan cleared Malaysian customs on Friday, in the first shipment of Taiwanese pomeloes to Malaysia. Taiwan-grown pomeloes are popular in domestic and overseas markets for their tender and juicy taste, the Ministry of Agriculture’s Animal and Plant Health Inspection Agency said. The fruit is already exported to Japan, Canada, Hong Kong, Singapore and the Philippines, it added. The agency began applying for access to the Malaysian market in 2023, compiling data on climate suitability, pests and diseases, and post-harvest handling, while also engaging in nearly two years of negotiations with Malaysian authorities and submitting supplementary
PEAK MONTHS: Data showed that on average 25 to 27 typhoons formed in the Pacific and South China seas annually, with about four forming per month in July and October One of three tropical depressions in the Pacific strengthened into a typhoon yesterday afternoon, while two others are expected to become typhoons by today, Central Weather Administration (CWA) forecaster Lee Ming-hsiang (李名翔) said yesterday. The outer circulation of Tropical Depression No. 20, now Typhoon Mitag, has brought light rain to Hualien, Taitung and areas in the south, Lee said, adding that as of 2pm yesterday, Mitag was moving west-northwest at 16kph, but is not expected to directly affect Taiwan. It was possible that Tropical Depression No. 21 would become a typhoon as soon as last night, he said. It was moving in a
One of two tropical depressions that formed offshore this morning could turn into a moderate typhoon by the weekend, the Central Weather Administration (CWA) said today. Tropical Depression No. 21 formed at 8am about 1,850km off the southeast coast, CWA forecaster Lee Meng-hsuan (李孟軒) said. It is expected to move in a northwesterly direction as it continues building momentum, possibly intensifying into Typhoon Mitag this weekend, she added. The radius of the storm is expected to reach almost 200km, she said. It is expected to approach southeast of Taiwan on Monday and pass through the Bashi Channel between Tuesday and Wednesday,
About nine Taiwanese are “disappeared,” detained, or otherwise deprived of freedom of movement in China each month, the Mainland Affairs Council (MAC) said yesterday. Between Jan. 1 last year and Aug. 31 this year, 188 Taiwanese travelers went missing, were detained and interrogated, or had their personal freedom restricted, with some questioned in airports or hotel lobbies, the council said. In a statement ahead of the Mid-Autumn Festival, the council urged people visiting China for any reason to be highly vigilant and aware of the risks. Of the reported cases, 50 people were “disappeared” after entering China, 19 were detained and 119 had