XMC's 3DLink™ Technology Empowers Xi'an UnilC's Stacked Embedded DRAM (SeDRAM) Platform

Recently, Wuhan Xinxin Semiconductor Manufacturing Co., Ltd. (XMC), a leading semiconductor R&D and manufacturing company, has carried out in-depth cooperation in professional fields with Xi'an UnilC Semiconductors Co., Ltd. (Xi'an UnilC). The 3DLink technology independently developed by XMC has empowered Xi'an UnilC's stacked  embedded DRAM (SeDRAM) platform and accelerated the technological innovation of the industry to achieve major breakthroughs: The stacked  embedded DRAM (SeDRAM) technology has reached the world's leading level. Relevant technical papers have been successfully included by IEDM 2020 and CICC 2021, and special reports have also been made in IMW 2021. Based on the new 3D IC technology platform (3DLink), XMC has brought several customized process solutions into mass production.

Xi'an UnilC applies XMC's 3DLink wafer-level stacking technology to design its SeDRAM platform through OEM cooperation, directly bonding DRAM wafers with logic wafers of other different process nodes using Cu-Cu (copper-copper) interconnections to achieve direct access to the memory. It supports a variety of memory densities (from 64MB, 128MB, 256MB to 8GB) and bandwidths through customized DRAM; At the same time, it provides standardized interfaces and test IPs for different logic processes, making SoC integration simpler and faster. XMC's 3DLink technology breaks through the limitations of the traditional package-level Micro-bump interconnection architecture and realizes high-density interconnection through direct bonding of multiple wafers, achieving bandwidth of up to 34GB/s per Gbit and energy efficiency of 0.88pJ/bit from logic circuit to storage array. Two SoC products based on the SeDRAM platform have been mass-produced at XMC.

"In traditional computer architectures, the bandwidth gap between the computing element and the memory, known as the memory wall problem, has been increasingly serious. The SeDRAM technology of Xi'an UnilC utilizes XMC's 3DLink wafer-level stacking technology platform to directly bond logic and DRAM wafers, providing the industry's leading embedded memory solutions with ultra-high bandwidth and ultra-low power consumption. With years of DRAM development and mass production and SoC design service capabilities, Xi'an UnilC continues to innovate and puts forward a parallel and efficient storage architecture, which enables the SeDRAM platform to burst out extremely competitive unit bandwidth and energy efficiency in the industry. As two subsidiaries of Tsinghua Unigroup, Xi'an UnilC and XMC have maintained a close and tacit friendship and cooperation for years. In the future, Xi'an UnilC will continue to promote deeper collaboration to provide fast and effective mass-production solutions for the ultra-high bandwidth and ultra-low energy consumption requirements in artificial intelligence (AI) and high-performance computing (HPC) fields," said  Jiang Xiping, Executive Vice President of Xi'an UnilC.

"The successful design of the SeDRAM platform and the efficient development of the multi-core SoCs are the results of a collaborative effort to further explore the strengths and potential of the 3DLink technology platform,"  said Sun Peng, COO of XMC. "The SeDRAM platform of Xi'an UnilC has high requirements for bandwidth, computing power, power consumption, etc. If advanced manufacturing processes are used to achieve the desired performance, it is not only costly but also difficult to ensure the stability of supply. XMC's 3D IC technology platform, 3DLink, can solve this problem. With the new idea of "More than Moore", XMC's 3DLink technology platform utilizes nanoscale interconnection technology and innovative architecture that enables customers to select mature manufacturing processes to achieve superior product performance. In the future, we will carry out in-depth joint customization development with partners to enhance the value of the 3DLink technology platform and provide our customers with competitive product solutions more efficiently."

About XMC 3DLink™ Technology Platform
XMC 3DLink™ is an industry's leading 3D IC technology platform which enables direct bonding of multiple wafers or wafers to chips in a vertical direction utilizing semiconductor nanoscale-interconnection technology. This platform includes three technology categories, two-wafer stacking technology (S-stacking®), multi-wafer stacking technology (M-stacking®) and heterogeneous integration technology (Hi-stacking™). Among them, S-stacking® is mainly used in fields such as sensors (CIS, ToF), high-speed computing and in-storage computing, and M-stacking® is mainly for high-bandwidth memory, etc. After years of experience in R&D and mass production, XMC has built up a stable and reliable wafer-level 3D stacking process platform. Meanwhile, XMC plans to develop heterogeneous integration technology (Hi-stacking™) which can be applied for bonding with different die sizes or substrate materials.

In addition to significantly reducing chip size and achieving wafer-level interconnection, XMC 3DLink™ technology can improve chip performance with faster I/O speed, higher bandwidth, lower latency and lower power consumption, providing a powerful solution for chips of sensor, high-speed computing and HBM, etc.

About XMC
Wuhan Xinxin Semiconductor Manufacturing Co., Ltd.(XMC), a leading semiconductor R & D and manufacturing company, was founded in Wuhan, China, in 2006. It focuses on developing advanced specialty processes, including 3D IC technology(3DLink), specialty flash memory process, and specialty logic process platform. XMC is committed to providing innovative products and world-class services to its global customers.

XMC has built up two 300mm fabs, each with a capacity of over 30,000 wafers/month.

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About SeDRAM of Xi'an UnilC
Xi'an UnilC's stacked embedded DRAM (SeDRAM) is the industry's leading embedded memory solution with ultra-high bandwidth and ultra-low power consumption. SeDRAMuses nanoscale interconnection technology to connect DRAM wafers with logic wafers of other different process nodes vertically to achieve direct access to the memory; supports a variety of memory densities (from 64MB, 128MB, 256MB to 8GB) and bandwidths through customized DRAM design; At the same time, it provides standardized interfaces and test IPs for different processes, so that SoC can be conveniently and easily integrated.

Relying on the open, customized and platform-based cooperation model, Xi'an UnilC, with years of DRAM development and mass production and SoC design service capabilities, will help customers with requirements on large bandwidth, low power consumption and high computing power to quickly develop products and bring them to the market.

About Xi'an UnilC
Xi’an UnilC Semiconductors Co., Ltd. (Xi’an UnilC), formerly known as the Memory Development Division of Xi’an R&D Center of Infineon Technologies in 2004, and was renamed as Qimonda Technologies (Xi’an) Co., Ltd. in 2006. After acquired by Inspur Group in 2009, the entity became a domestic company and was renamed as Xi’an Sinochip Semiconductors Co., Ltd. It came to the present name after the acquisition by Tsinghua Unigoup in 2015. According to the Tsinghua Unigroup announcement, Xi'an UniIC is transferred to Unic Memory in 2019.  

Xi’an UnilC has nearly 500 employees.It has an international R&D team with key memory and ASIC design and testing technologics. The core businesses are focused on the development of memory products, marketing and sales of self-owned brand memory products, and ASIC design services. Since its establishment, the company has been working on the R&D in memory especially in DRAM technologies. Many products has been in mass production and volume shipment to serve domestic and international customers. The company has accumulated extensive R&D and industrialization experience in memory design, testing, mass production, as well as global sales and marketing.

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