Author: Peng Cheng
Only a handful of companies globally have achieved mass production of MRAM. For a long time, this track has been dominated by a few top players: Everspin is the only publicly listed company in the world with MRAM as its core business; Samsung and TSMC integrate embedded MRAM into advanced logic processes; NXP applies MRAM to automotive-grade MCUs.
Within this small circle, domestic manufacturers are rapidly gaining presence: HikStor Technology's MRAM products have entered mass production and penetrated industrial and automotive sectors; Shanghai Siproin's STT-MRAM has completed commercial shipments; Zhizhen Storage's SOT-MRAM chips have been validated in drone flight controllers. Behind the rise of domestic vendors is the gradual formation of a complete supply chain. Beyond terminal applications, critical upstream materials and core equipment bottlenecks are being resolved one by one.
01、Materials: Magnesium Oxide Was the Final Missing Piece
The core memory cell of MRAM is the Magnetic Tunnel Junction (MTJ), composed of multilayer metal and insulating thin films stacked with thicknesses under ten nanometers, relying on the direction of magnetic moments in the magnetic layers for data storage. Fabricating these multilayer films requires a series of high-purity sputtering targets, including cobalt-iron-boron magnetic targets, platinum-manganese antiferromagnetic targets, ruthenium spacer layer targets, and magnesium oxide targets serving as insulating barriers. Using high-precision sputtering processes, ultra-high-purity magnesium oxide can be deposited as an ultra-thin single-crystal film with a thickness of 1-2 nm, forming a uniform and dense insulating barrier structure. The regular lattice structure generates stable spin-filtering effects, selecting electrons with specific spin states to complete quantum tunneling, providing the foundational structural support for chip magnetoresistance switching and data read/write operations. This is the key carrier enabling MRAM storage functionality.
In August this year, Suzhou Zhicai Technology announced the success of its independently developed 6-inch MRAM-MgO target material. The product is semi-transparent, with purity reaching 4N, density exceeding 99.8%, and grain uniformity among other key indicators meeting international advanced levels (mainstream Japanese target materials have densities >99.7%). This means that domestic MRAM chip mainstream manufacturers and research institutions, previously subject to international interference, now have an option for self-controlled domestic core material supply.
Magnesium oxide targets are used for the insulating barrier layer of MTJs, where the quality of the sputtered film directly determines the device's Tunnel Magnetoresistance (TMR) ratio and yield. Previously, this relied heavily on imports. Therefore, the industry set extremely high technical thresholds for target purity, density, and grain uniformity. Prior to this, the remaining metallic magnetic targets required for MTJ multilayer films had largely achieved localized self-sufficiency; magnesium oxide was the last bottleneck.
In addition, domestic manufacturers such as Grinm Advanced Materials and Henan Dongwei Electronic Materials have all entered the spintronic chip target supply chain. It is understood that Dongwei Electronics holds the No. 1 market share nationally for MRAM series targets, supplying major manufacturers with bulk quantities of cobalt-iron-boron and magnesium oxide targets, among which the cobalt-iron-boron target is exclusively mass-produced domestically.
The true significance of material localization lies not in individual targets but in supply security. Most main R&D institutions for MRAM faced dual constraints from overseas critical materials, with the risk of target supply cuts hanging over production lines. Now that suppliers for all functional layer materials of magnetic tunnel junctions can be found domestically, this risk has truly been eliminated.
02、Equipment: Dedicated Process Equipment for MRAM Emerges
Pushing one layer down from materials leads to equipment that etches these films into devices. In MRAM device fabrication, milling of the magnetic tunnel junction is the most critical process step. On one hand, the MTJ consists of more than 20 sub-nanometer thick metallic functional layers (involving metals like platinum, iron, cobalt, manganese) and oxide dielectric layers (magnesium oxide). The film quality of each layer and the physicochemical bonds formed at interfaces between layers are closely related to memory device performance. Traditional plasma etching cannot form volatile residues from metal etching to be pumped away by vacuum pumps, inevitably causing residue accumulation on the sidewalls of adjacent MTJs and the reactor chamber walls, leading to contamination and short circuits, thereby causing device failure and reduced production yields. Especially as logic circuit technology generations advance and device sizes shrink, compatible MTJ dimensions become smaller and denser, making residue accumulation problems increasingly severe. On the other hand, if the MTJ is exposed to the atmospheric environment after etching, it reacts with moisture in the air, causing device failure.
Jiangsu Luwen Instrument is the representative domestic enterprise in this field. Its ion beam shaping equipment integrates 1 Ion Beam Shaping (IBS) chamber, 2 ICP etching chambers, and 1 PEVCD chamber on the same vacuum transfer platform. On one hand, using both IBS and ICP etching process chambers synergistically to complete MTJ milling effectively solves process challenges such as metallic sidewall contamination mentioned above, making large-scale mass production of emerging memories like MRAM possible. Compared to international leaders like Lam Research, which currently use only ion beam shaping for MTJ milling, the synergistic approach of ion beam shaping and ICP etching offers faster etch rates and higher yields. On the other hand, integrating a PECVD process chamber allows depositing a passivation layer inside the equipment's vacuum environment immediately after etching, effectively isolating air and avoiding device failure. Additionally, integrating another ICP etching chamber enables hard mask layer etching necessary before MTJ etching, further enhancing equipment integration and mass production efficiency.
Luwen Instrument's first-generation emerging memory process equipment, LMEC-200, secured orders from China Taiwan's Industrial Technology Research Institute (ITRI) from international vendors back in 2018; the upgraded 12-inch LMEC-300 has been delivered to customers and achieved acceptance sales, selected for Jiangsu Province's First Set Major Equipment list in 2022. In June this year, Luwen Instrument's IPO application on the SSE STAR Market was accepted, planning to raise CNY 2.5 billion.
Beyond front-end process equipment, back-end testing equipment was also an easily overlooked bottleneck. Testing magnetic chips requires simultaneous electrical read/write and fail-bit map collection under controlled magnetic fields and wide temperature ranges, which general-purpose testers cannot handle. Qingdao Zhizhen Precision Instruments' spintronic chip reliability test equipment provides up to 2000 Oe uniform magnetic field and -55°C to 170°C temperature environments, having entered SOT-MRAM magnetic immunity research by teams at Beihang University and other institutions; its wafer-level Magneto-Optical Kerr Effect (MOKE) measurement instruments and TMR ratio measurement instruments cover multiple nodes from R&D characterization to mass production testing.
03、Manufacturing: Achieving Closed Loop for MRAM Mass Production
Once materials and equipment are in place, the production line becomes the determinant of industrial strength.
HikStor Technology has built its own 12-inch MRAM production line, establishing three mass production platforms at 90nm, 40nm, and 28nm, offering standalone products and embedded IP customization. It is the only manufacturer in China capable of providing mass-produced MRAM products. The team independently developed and mastered full-chain key technologies for third-generation MRAM (STT-MRAM) chips, from design, components, process manufacturing, testing evaluation to application development. Products cover capacities from 256kb to 64Mb, widely applied in smart IoT, industrial automation, enterprise storage, identity authentication, AI, and commercial aerospace.
However, it must be clearly recognized that the process window for embedded MRAM in advanced nodes remains overseas. Hanxu Technology's 8nm eMRAM tape-out relies on Samsung's process, while TSMC expects to complete preparation for 5nm MRAM mass production by 2027. Domestic manufacturing has closed the loop on mature nodes but still lags significantly behind TSMC and Samsung in advanced eMRAM.
04、Devices: Three Routes Advancing Simultaneously
Above the production line lies the divergence of routes at the device level. The overall landscape of domestic MRAM can be summarized as: "STT-MRAM has achieved industrialization, SOT-MRAM has completed frontier technological breakthroughs, and MRAM computing-in-memory has achieved global parity."
STT-MRAM commercialization progress is relatively fast. HikStor Technology has constructed a product matrix ranging from Kb to hundreds of Mb levels, and Shanghai Siproin has achieved commercial shipments. Globally, Everspin's latest UNISYST MRAM products reach densities of 128Mb-2Gb with read bandwidths of 400MB/s, targeting the standalone NOR Flash replacement market valued at approximately USD 3 billion. In the standalone MRAM track, the technology gap between domestic enterprises and international giants is continuously narrowing.
The SOT line represents the next generation of technology directions. SOT-MRAM uses Spin-Orbit Torque (SOT) to drive magnetic moment reversal, offering faster read/write speeds and higher endurance, but with more complex device structures and processes. Zhizhen Storage's 256Kb SOT-MRAM chip has completed commercial validation in drone flight controllers; HikStor Technology innovatively proposed a channel-less (CHL) device architecture, integrating the tunnel junction and channel layer into a unified design, allowing device fabrication via a single etch step. During etching, over-etching down to the Bottom Electrode (BE) improves device yield to over 99.9%; The National Key Laboratory of Spintronic Chips and Technologies released the world's first fully functional third-generation MRAM chip with a monolithic capacity of 4 Mb—SOT-MRAM chip, which is also the world's first vertically magnetized SOT-MRAM chip with Mb capacity.
The Computing-in-Memory (CIM) line bets on AI. MRAM CIM chips embed matrix multiplication operations within memory cells, eliminating the massive energy consumption caused by repeated data movement between storage and computing units in traditional architectures. Previously, the Key Laboratory of Information Storage System at Huazhong University of Science and Technology released "Yujia Mountain No. 1," then the largest capacity MRAM CIM chip globally, adopting entirely domestic processes with power consumption only one-thousandth of traditional chips. In June this year, R&D of the "Yujia Mountain No. 2" chip entered a critical phase, aiming to iterate and upgrade based on "Yujia Mountain No. 1" technology to further enhance computing power and energy efficiency. A team from Southern University of Science and Technology successfully designed and taped out a 64kb non-volatile digital CIM chip using 40nm CMOS and STT-MRAM processes, achieving single-bit input and stored weight multiplication within STT-MRAM bit cells and directly outputting digital results; Hanxu Technology's 8nm eMRAM AI chip combines embedded storage with CIM architecture, supporting edge-side operation of large models with 2 billion parameters.
The value of devices is ultimately realized through actual scenarios. With characteristics such as non-volatility, nanosecond write speed, trillion-cycle endurance, wide temperature range, and radiation resistance, MRAM will not enter the red ocean of consumer storage markets first but will prioritize building market advantages in automotive and industrial scenarios with stringent reliability requirements; Edge AI is a newly opened incremental track. Large model inference on the edge is limited by power consumption and space; eMRAM unit sizes are much smaller than SRAM and require no refresh, providing new storage options for edge devices.
05、Conclusion
As links in the supply chain are gradually connected, collaborative construction of the industrial ecosystem is accelerating. In December 2025, the First Spintronic Chip and Technology Symposium was held in Hangzhou, and the Spintronic Chip Industry Innovation Alliance was unveiled. Domestic MRAM has passed the stage of "individual breakthroughs" and begun to establish industrial organization and technical standards. For capital-intensive, long-cycle, and highly collaborative industries like novel memory, the value of alliances and standards is no less than single-point technological breakthroughs; they determine whether enterprises along the chain can collaborate using the same language.
Between 2025 and 2026, domestic MRAM crossed thresholds in five segments: materials, equipment, manufacturing, design, and application. Localization of target materials and etchers reduced line construction costs, production line deployment amplified design team iteration speed, and device maturity in turn supported alliances and standards. However, shortcomings remain clear: the process window for advanced node eMRAM is still held by TSMC and Samsung. But this is precisely the significance of connecting the supply chain; future competition is no longer a race against international levels in individual segments, but a comprehensive offensive by a complete chain against the generational gap.