Patents - Page 2

Researchers from the University of Virginia have developed a novel technology using MRAM for short- and long- term storage solutions. This device uses a spinning torque current to change the magnetization of each memory domain to achieve higher memory bit density and faster writing speeds. These memory domains are allocated along the memory line and a multi-ferroic element near each domain provides magnetization stability when a voltage is not being applied.

To write the individual bit, a current is passed through the memory line and the interaction of the multi-ferroic element and the free layer determines either “1” anti-parallel polarity between layers (high resistance) or “0” parallel polarity between layers (low resistance). The magnetization of the memory domains is then changed by reducing the exchange bias between the memory line and the multi-ferroic element (see figure above). Memory domains are independently writable and only require a single current input to store data. This significantly reduces energy consumption and time for the writing cycle, thereby improving both cost and performance efficiency.

Back in January we reported that NVE filed a patent infringement lawsuit against Everspin Technologies in the US. NVE claims that Everspin infringes three NVE MRAM patents. Today Everspin responded with a suit of their own, claiming that NVE infringed on two US patents related to GMR-based isolators, sensors, encoders and memory.

A*STAR scientists have filed a patent on low-density parity-check (LDPC) coding with soft decision decoding. This is an advanced error correction coding scheme STT-MRAM devices. Hopefully this new scheme will enable more relaxed smaler STT-MRAM designs that can rely on the error-correction.

STT-MRAM devices suffer from cell errors due to imperfections in the fabrication process (variation in the tunneling oxide thickness and cross-section area). The researchers explain that conventional (hard decision) error correction codes do not work very well on STT-MRAM cells. The new soft decision decoding works on the probability of each detected bit as being a 0 or 1 (i.e. soft reliability), and hence has less decoding errors than the conventional hard decision decoding.

NVE filed a patent infringement lawsuit against Everspin Technologies in the US. NVE claims that Everspin infringes three NVE MRAM patents. NVE seeks an injunction for Everspin to cease using NVE?s patented technology and provide compensation for damages caused by the infringement.

Everspin was spun-off Freescale, which was spun-off from Motorola, which was an NVE licensee. Back in 2006, when Freescale announced the first MRAM products, NVE tried to negotiate an agreement with them, it seems that after 5 and a half years the company decided to resort to litigation after all. Here's what Daniel Baker (NVE's CEO) said back then: "Based on a preliminary analysis, we believe Freescale's MRAM comes within the scope of claims in a number of NVE patents. We hope to negotiate a mutually beneficial agreement with Freescale to give them access to NVE intellectual property without having to resort to litigation"

HP says that their two terminal memristor (Resistive RAM) technology will be launched in 18 months - and will "start to take market share from flash memory". The company has 'big plans' for the new memory technology and are working with Hynix to launch the flash replacement chip in 2013. The company also plans to go after the DRAM market in 2014/2015 and later the SRAM market as well.

HP has over 500 patents on this technology alone - but it isn't the only company working on memristor devices - in fact Samsung has an even bigger team working on a similar project.

Crocus signed a joint technology development agreement and a mutual patent license agreement with IBM. They also signed a technology agreement - under which they will jointly develop semiconductor technology that combines Crocus' thermally assisted next generation Magnetic-Logic-Unit (MLU) technology with IBM's MRAM technology and processing capabilities.

MLU is a scalable evolution of Crocus' Thermally Assisted Switching (TAS) technology, and enables practical implementation of advanced magnetic logic and memory capabilities.

Crocus announced that they acquired NXP Semiconductor's MRAM patent portfolio - which includes fundamental MRAM intellectual property rights in multiple geographies worldwide, including North America, Europe and Asia.

Crocus now holds over 100 issued and pending patents related to the magnetic semiconductor technology covering magnetic materials, devices, and design and product technology.

Researchers from the Physikalisch-Technische Bundesanstalt (PTB) developed new technology that can make MRAM much faster - from about 400Mbit/s data rate to 2Gbit/s. According to PTB, the new tech will also reduce power consumption and thermal load and will make the MRAM chip more reliable (reduce the bit error rate). PTB has patented this technology and are looking to find an industrial partner to develop and manufacture MRAM chips.

PTB has integrated ballistic bit triggering into the MRAM cell. This basically means that their technology allows changing (writing) one MRAM cell without affecting the cells around it - which reduces error rates. Here's how they describe it: "The (magnetic) pulse ensures that the magnetization of a cell which is to be switched performs half a precision rotation (180°), while a cell whose storage state is to remain unchanged performs a complete precision rotation (360°). In both cases, the magnetization is in the state of equilibrium after the magnetic pulse has decayed, and magnetic excitations do not occur any more."

NVE reported their financial results, and in the conference call they gave some interesting new details about their MRAM program. Daniel Baker (the CEO) says that NVE 'overcame many of the technical challenges in making MRAM'. In fact, the company is already shipped some sample prototype MRAM chips, but they don't call it 'production' yet. The samples will be for specialized niche applications - but the company sees this as a 'vehicle to develop MRAM technology'. In the future the company hopes to address large volume anti-tamper applications such as to prevent identity theft or improve the security of credit cards and smart cards.

In regards to Everspin being a licensee, here's what they say - "EverSpin is a company that's making and selling commercial MRAM, and they are spin-off of Freescale, which was a spin-off of Motorola. So, we have a long historical relationship. Motorola was an early investor in NVE, and we had research contracts and intellectual property agreements with Motorola. So, we believe that they share our vision for a very bright future for MRAM"

NVE was granted a new patent (number 7,813,165) titled “Magnetic Memory Layers Thermal Pulse Transitions,” relating to Magnetothermal MRAM.

NVE explains that Magnetothermal MRAM is an MRAM design that uses a combination of magnetic fields and ultra-fast heating from electrical current pulses to reduce the energy required to write data.