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.
A magnitude 6.4 earthquake struck off the coast of Hualien County in eastern Taiwan at 7pm yesterday, the Central Weather Administration (CWA) said. The epicenter of the temblor was at sea, about 69.9km south of Hualien County Hall, at a depth of 30.9km, it said. There were no immediate reports of damage resulting from the quake. The earthquake’s intensity, which gauges the actual effect of a temblor, was highest in Taitung County’s Changbin Township (長濱), where it measured 5 on Taiwan’s seven-tier intensity scale. The quake also measured an intensity of 4 in Hualien, Nantou, Chiayi, Yunlin, Changhua and Miaoli counties, as well as
Credit departments of farmers’ and fishers’ associations blocked a total of more than NT$180 million (US$6.01 million) from being lost to scams last year, National Police Agency (NPA) data showed. The Agricultural Finance Agency (AFA) said last week that staff of farmers’ and fishers’ associations’ credit departments are required to implement fraud prevention measures when they serve clients at the counter. They would ask clients about personal financial management activities whenever they suspect there might be a fraud situation, and would immediately report the incident to local authorities, which would send police officers to the site to help, it said. NPA data showed
ENERGY RESILIENCE: Although Alaska is open for investments, Taiwan is sourcing its gas from the Middle East, and the sea routes carry risks, Ho Cheng-hui said US government officials’ high-profile reception of a Taiwanese representative at the Alaska Sustainable Energy Conference indicated the emergence of an Indo-Pacific energy resilience alliance, an academic said. Presidential Office Secretary-General Pan Men-an (潘孟安) attended the conference in Alaska on Thursday last week at the invitation of the US government. Pan visited oil and gas facilities with senior US officials, including US Secretary of the Interior Doug Burgum, US Secretary of Energy Chris Wright, Alaska Governor Mike Dunleavy and US Senator Daniel Sullivan. Pan attending the conference on behalf of President William Lai (賴清德) shows a significant elevation in diplomatic representation,
The Taipei MRT is to begin accepting mobile payment services in the fall, Taipei Rapid Transit Corp said on Saturday. When the company finishes the installation of new payment units at ticketing gates in October, MRT passengers can use credit cards, Apple Pay, Google Pay and Samsung Pay, the operator said. In addition, the MRT would also provide QR payment codes — which would be compatible with Line Pay, Jkopay, iPass Money, PXPay Plus, EasyWallet, iCash Pay, Taiwan Pay and Taishin Pay — to access the railway system. Currently, passengers can access the Taipei MRT by buying a single-journey token or using EasyCard,
RSS