The “China Materials Conference 2025” Advanced Microelectronics and Optoelectronics Materials Sub-forum was successfully held.

From July 5 to 8, 2025, the "China Materials Conference 2025" will be held with great solemnity at the Xiamen International Convention and Exhibition Center in Fujian Province. The "China Materials Conference" is the annual academic conference of the Chinese Society for Materials Research, one of the most important and well-established series of conferences in China. It is a large-scale academic event—attended by over 10,000 participants—that boasts the highest academic standards in China's new materials field, covers the broadest range of disciplines, and keeps abreast of the latest cutting-edge developments. This conference is a high-level, brand-name event aimed at addressing major national needs and driving groundbreaking advances in new materials. This year’s conference covers five major thematic areas: energy materials, environmental materials, advanced structural materials, functional materials, and materials design, preparation, and evaluation. In addition, a number of specialized forums will be held concurrently, including a Youth Forum, a Special New Materials Forum, a Materials Education Forum, and a Materials Journals Forum. Moreover, an international exhibition of new materials research instruments and equipment will take place simultaneously, providing a diverse platform for representatives with different needs to engage in meaningful exchanges. Nearly 30,000 materials science and technology professionals, corporate representatives, and young scholars from across China will gather to jointly explore and share cutting-edge technologies and the latest research findings in the field of materials, sparking brilliant intellectual collisions.

The “Advanced Microelectronics and Optoelectronics Materials Sub-venue,” organized by the Integrated Circuit Materials Industry Technology Innovation Alliance and jointly supported by the Shanghai Institute of Microsystem and Information Technology of the Chinese Academy of Sciences, the Beijing Multi-Dimensional Electronic Materials Technology Development and Promotion Center, the Beijing Superstring Memory Research Institute, and the Integrated Circuit Professional Committee of the Shanghai Electronics Society, was held concurrently. This sub-venue aims to promote exchanges and cooperation among experts, scholars, and industry representatives in China’s microelectronics and optoelectronics materials fields, share the latest research findings on microelectronics and optoelectronics materials, processes, and devices, and further enhance China’s academic standards and technological innovation capabilities in these fields.

Researcher Zhao Chao from the Beijing Superstring Memory Research Institute serves as the Chair of the “Advanced Microelectronics and Optoelectronics Materials Subsession.” Researcher Yu Wenjie, Deputy Director of the Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, and Academician Yang Deren from Zhejiang University serve as Vice Chairs of the subsession. This “Advanced Microelectronics and Optoelectronics Materials Subsession” features 14 invited talks, 22 oral presentations, and 9 poster presentations. The number of participants exceeds 60. The presented papers cover a wide range of topics in the fields of microelectronics and optoelectronics materials, including: novel storage materials and technologies, wide-bandgap semiconductor materials and devices, heteroepitaxial integration materials and devices, new display materials, and other materials used in the fabrication of integrated circuits and optoelectronic devices; advanced packaging materials; carbon-based functional materials such as carbon nanotubes and graphene—along with other novel two-dimensional materials; material characterization techniques and methods; and materials design theories and computational simulations.

Opening remarks by Researcher Zhao Chao, Chair of the Conference and Researcher at the Beijing Superstring Memory Institute.  

Professor Qian He from Tsinghua University was invited to deliver an invited talk entitled “RRAM Process Modules and Macrocells Based on the 28/22nm CMOS Platform.” The talk primarily introduced the team’s developed RRAM process modules and corresponding macrocells based on the 28/22nm CMOS foundry. These include material stack optimization, device sidewall protection, elimination of initial low resistance (ILR), macrocell design techniques, and optimization of storage characteristics through algorithmic control. The resulting macro IP demonstrates excellent performance and is ideally suited for MCU, smart card, DDIC, and other SoC applications requiring eNVM. It is also highly compatible with processing-in-memory chips.

Professor Qian He from Tsinghua University delivers an invited talk.

Researcher Hangbing Lu from Xiamen University was invited to deliver an invited talk titled “High-Performance Hafnium-Based Ferroelectric Memory.” The talk covered several aspects, including the phase-transition kinetics of hafnium-based ferroelectric materials, device reliability, and technological applications. In terms of material mechanisms, the talk elucidated the formation mechanism of the ferroelectric phase as well as the degradation mechanisms under post-process thermal budgets. Regarding device reliability, through structural and electrical characterization, a dual-fatigue mechanism model was proposed, accounting for both the irreversible ferroelectric-to-monoclinic phase transition under high electric fields and the reversible ferroelectric-to-pbca phase transition under low electric fields. Simultaneously, an electrical model was established for hafnium-based ferroelectric memory under various reliability scenarios, including retention, endurance, and interval-read performance. On the technological application front, leveraging the insights gained from the mechanistic studies, a 32-Mb embedded 3D FeRAM chip based on a 40-nm CMOS process was successfully developed. This chip demonstrates exceptional endurance exceeding 10^13 cycles at 125°C and retention characteristics lasting up to 10 years, highlighting the tremendous potential of hafnium-based ferroelectric memory technology in terms of storage density and performance.

Researcher Lü Hangbing from Xiamen University delivered an invited talk.

Professor Jie Zhi Chen from Shandong University was invited to deliver an invited talk titled “Key Technological Pathways for Flash Memory in the AI Era.” Against the backdrop of the rapid advancement of artificial intelligence (AI) technologies, storage technologies are undergoing a transformative leap—from two-dimensional planar architectures to three-dimensional vertical architectures. Among these, 3D NAND flash memory, with its advantage of three-dimensional stacking, has quickly become the mainstream choice in the high-capacity non-volatile memory market. However, while the three-dimensional architecture significantly boosts storage density, it also brings unprecedented reliability challenges. The multi-layer stacking process, the vertical array architecture, and the unique requirements under compute-in-memory scenarios all contribute to highly complex degradation mechanisms and reliability optimization strategies. To build a highly reliable storage system tailored for the AI era, there is an urgent need to establish a full-stack collaborative optimization methodology that integrates everything from the physical properties of storage media to system architecture design. In this talk, Professor Chen elaborated on reliability optimization strategies based on the underlying physical characteristics of flash memory media, analyzed the application potential of flash memory in compute-in-memory technologies, and outlined key technological pathways for the future development of three-dimensional storage chips.

Professor Chen Jiezhi from Shandong University delivered an invited talk.

Professor Yue Zhang from Beijing University of Aeronautics and Astronautics was invited to deliver an invited talk titled “Spin-Storage Materials and Device Technologies.” Spintronics leverages the intrinsic spin property of electrons to achieve non-volatile information storage, offering advantages such as low power consumption, high speed, high density, and radiation resistance. It holds great promise for breaking through the power-consumption bottlenecks of traditional CMOS technology and supporting the rapid development of emerging applications such as the Internet of Things and artificial intelligence. By integrating non-volatile storage with reconfigurable logic computing capabilities, spin-memory devices can be further integrated into “compute-in-memory” architectures, providing an effective solution to the “von Neumann architecture bottleneck” problem. The talk presented the latest advances in spin-storage materials and devices, covering aspects including functional material growth, exploration of underlying physical mechanisms, optimization of device structures, and chip development.

Professor Zhang Yue from Beijing University of Aeronautics and Astronautics delivered an invited talk.

Researcher Shang Dashan from the Institute of Microelectronics of the Chinese Academy of Sciences was invited to deliver an invited talk titled “Memristor Computing Technology.” Human society is transitioning from the information age to the intelligent age. In this transition, the application of edge artificial intelligence (AI) is steadily increasing, covering a wide range of fields including scientific research, healthcare, transportation, and daily life. However, a key challenge currently facing us is how to enable richer AI functionalities on edge devices with limited computational resources. A memristor is a device whose electrical resistance can be adjusted to multiple distinct resistance states under the influence of an external electric field and which also exhibits a certain degree of memory capability regarding the adjustment process. By constructing large-scale memristor arrays and integrating them with appropriate peripheral circuits, memristors can perform highly energy-efficient computations within a compute-in-memory paradigm, offering a novel underlying hardware solution for realizing edge-intelligent devices. The talk introduced the systematic research conducted by the research group in recent years on memristor devices, algorithms, and chips. The research results demonstrate the potential of memristors in building edge-intelligent systems and also provide valuable references for developing high-energy-efficiency intelligent hardware systems based on the abundant physical and chemical properties found in nature.

Researcher Shang Dashan from the Institute of Microelectronics, Chinese Academy of Sciences, delivered an invited talk.

Professor Wu Jixuan from Shandong University was invited to deliver an invited talk titled “Research on the Physical Properties and Device Reliability of Hafnium-Based Ferroelectric Materials.” Ferroelectric materials have long been widely used in memory devices owing to their low-power consumption characteristics. In this talk, the speaker employed first-principles computational simulations to explore in depth the mechanisms underlying ferroelectric phase formation in pure HfO₂ and Si-doped HfO₂ under finite-size and temperature conditions, with a particular focus on surface energy, entropy, and the energy barrier for polarization reversal. The presentation also systematically investigated the reliability issues of 7-nm HZO capacitors at high temperatures, and for the first time observed the “re-wakeup” phenomenon during thermal cycling. Analysis revealed that positive charge trapping at grain boundary defects leads to domain pinning; however, the enhanced electron injection effect at elevated temperatures can release this pinning and re-activate polarization behavior. This phenomenon highlights the profound relationship between defect evolution and device performance under thermally activated conditions, underscoring the importance of grain boundary engineering in improving the reliability of ultra-thin HZO films. By integrating thermodynamics, kinetics, device structure, and defect behavior, this study provides a comprehensive understanding of the polarization mechanisms and reliability control rules governing hafnium-based ferroelectric materials, offering both theoretical foundations and practical guidelines for optimizing ferroelectric thin-film performance and advancing their application in future high-density, low-power memory devices.

Professor Wu Jixuan from Shandong University delivered an invited talk.

Professor Wang Xinran from Nanjing University was invited to deliver an invited talk titled “Two-Dimensional Semiconductor Materials, Devices, and Integration Technologies.” As integrated circuits enter the “post-Moore era,” there is a pressing need for fundamental innovations in both underlying materials and circuit architectures. Two-dimensional semiconductor materials, with their ultra-thin channel thickness and compatibility with low-temperature back-end heterogeneous integration, represent the ultimate path for sustaining Moore’s Law and also serve as one of the key pathways for China to break through in integrated circuit technology. The talk focused on the goal of integrating chips based on silicon fusion, presenting the team’s recent advances in the epitaxial growth of two-dimensional semiconductor single crystals, high-performance transistor devices, integrated circuits, and AI chips. It also outlined future development trends and challenges in this field and highlighted the strategic initiatives being undertaken by Nanjing University and the Suzhou Laboratory in this area.

Professor Wang Xinran from Nanjing University delivered an invited talk.

Professor Guangwei Xu from the University of Science and Technology of China was invited to deliver an invited talk titled “Gallium Oxide Semiconductor Power Electronic Devices.” Gallium oxide, with its ultra-wide bandgap, boasts a high critical breakdown field strength and a high power quality factor. It can be grown into single crystals via the melt-growth method, which is fast and cost-effective, giving it significant application advantages in the fields of energy, information, and national defense. The main content of the presentation included: (1) Research progress on MOCVD epitaxial growth and micro- and nano-fabrication techniques for the surface and interfaces of gallium oxide; (2) Design and development of high-efficiency terminal structures: We have developed thermal oxidation high-resistance terminals, junction-terminal extensions, mesa terminals, and composite terminal structures. Additionally, we have pioneered controlled carrier growth using nickel oxide, selective thermal oxidation processes, and low-damage etching techniques, effectively suppressing edge peak electric fields and successfully fabricating gallium oxide power diode devices with high current-carrying capacity and excellent reverse-blocking capability; (3) Design and development of novel transistor structures: By adopting two approaches—thermal oxidation annealing and N-ion implantation—we have created, for the first time, a gallium oxide quasi-inversion-mode trench transistor.

Professor Guangwei Xu from the University of Science and Technology of China delivered an invited talk.

Researcher Song Zhitang from the Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, was invited to deliver an invited talk entitled “Semiconductor Phase-Change Memory.” The talk presented the research group’s recent advances in phase-change memory research, including the reversible phase-transition mechanisms of phase-change materials, high-speed phase-change materials, high-performance switching materials and their underlying mechanisms, as well as the integration of phase-change memory processes. The talk focused on the process and experience of screening mass-producible phase-change materials using the octahedral unit-cell-based phase-transition theory. It also highlighted the team’s progress in the industrialization of phase-change memory; currently, the team has achieved mass production and sales of embedded phase-change memory devices. Looking ahead, the team’s primary focus will be further expanding the large-scale application of phase-change memory in fields such as MCUs.

Researcher Song Zhitang from the Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, delivered an invited report.

Professor Kang Jinfeng from Peking University was invited to deliver an invited talk entitled “Three-Dimensional Integration of Ferroelectric Oxide Thin-Film Transistors.” Based on hafnium-based ferroelectrics and oxide semiconductors, the novel ferroelectric thin-film transistor—specifically, the ferroelectric oxide thin-film transistor—has emerged as a leading candidate for future high-density three-dimensional integrated memory and in-memory computing systems due to its outstanding storage-device characteristics and compatibility with CMOS technology. Consequently, its three-dimensional monolithic integration technology has become a key research focus. However, conventional amorphous oxide semiconductors such as IGZO face significant challenges in achieving three-dimensional monolithic integration because of their incompatibility with hafnium-based ferroelectric thin-film materials in terms of both material properties and fabrication processes. In this talk, we introduce a new type of ferroelectric thin-film transistor that uses crystallized TiO2 semiconductor—a material compatible with both the properties and fabrication processes of hafnium-based ferroelectric materials—as the channel material, along with a corresponding three-dimensional integration scheme. The presentation covers the device’s storage characteristics, reliability, potential for realizing high-density three-dimensional integration, as well as the challenges that remain to be addressed.

Professor Kang Jinfeng from Peking University was invited to deliver a keynote speech.

Professor Si Mengwei from Shanghai Jiao Tong University was invited to deliver an invited talk titled “Characterization of Defects and Investigation of Stability Mechanisms in ALD Oxide Semiconductor Devices.” Metal oxide semiconductor materials, with their wide bandgap and low leakage characteristics, are among the best candidates for realizing the semiconductor channels of DRAM selection transistors. Clarifying the reliability mechanisms and optimization strategies for oxide semiconductor devices and achieving high-reliability devices represent one of the key challenges facing this field. It is crucial to characterize and understand the types and formation processes of defects, as well as to elucidate how these defects affect device performance and DRAM storage cell behavior. The talk presented the research group’s recent progress in the study of oxide semiconductor device reliability and defect characterization, focusing on photoluminescence and physical characterization methods for defects in ALD IGZO devices, along with studies on the underlying mechanisms and stability mechanisms of ALD IGZO devices and related optimization approaches.

Professor Si Mengwei from Shanghai Jiao Tong University delivered an invited talk.    

Professor Huang Shaoyun from Peking University was invited to deliver an invited talk entitled “Research on Semiconductor Ge/SiGe Heterojunction Gate-Controlled Quantum Devices.” The spin-qubit scheme based on semiconductor gate-controlled quantum dots boasts the advantage of compatibility with advanced CMOS processes, making it one of the most promising candidates for scalable quantum computing. Using a fabrication process compatible with standard semiconductor micro- and nanofabrication techniques, the team prepared various low-dimensional gate-controlled quantum devices on undoped Ge/SiGe planar heterojunctions. At low temperatures, they systematically investigated the hole quantum transport properties under quantum confinement. By observing integer quantum Hall effects and signatures of fractional quantum Hall states, they confirmed the low disorder level of this undoped Ge/SiGe heterojunction system and demonstrated that the quantum scattering time is a key metric for assessing the quality of quantum transport and device performance in this material. Furthermore, by measuring quantized conductance plateaus, they verified the quasi-one-dimensional quantum confinement characteristics of the undoped Ge/SiGe heterojunction and highlighted the large g-factor and its tunability under quantum confinement conditions. After systematically optimizing both the device fabrication process and device structure, the team successfully fabricated high-quality, undoped Ge/SiGe heterojunction double-gate quantum dot devices, achieving single-hole control at 1.7 K, as evidenced by Coulomb oscillations and Coulomb diamond patterns.

Professor Huang Shaoyun from Peking University delivered an invited talk.

Professor Rongmei Chen from Peking University was invited to deliver an invited talk titled “Advances in Advanced Three-Dimensional Integrated Circuit Design and Process Technology.” As the traditional Moore’s Law for integrated circuits gradually loses its validity, three-dimensional integration is widely recognized as the only viable path to sustaining Moore’s Law at the system-on-chip level. The talk provided an overview of the historical development of three-dimensional integration, as well as the latest research and application advancements in this field. From a narrow perspective, three-dimensional integration can be broadly categorized into two types: quasi-three-dimensional (or 2.5D) integration and true three-dimensional integration. In turn, true three-dimensional integration can be further divided into monolithic three-dimensional integration and package-based three-dimensional integration. The talk conducted an analysis and discussion of these various three-dimensional integration approaches from three key dimensions—process technology, design, and applications—and introduced representative research institutions and their respective achievements in each of these three dimensions.

Professor Rongmei Chen from Peking University delivered an invited report.

In addition, more than 20 teachers and students—including Qi Ruijuan from East China Normal University, Li Dongke from Zhejiang University, Sun Rujun from Xidian University, Fu Wenxin from the Institute of Chemistry, Chinese Academy of Sciences, Yi Ailun from the Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, and Shi Lingying from Sichuan University—delivered outstanding oral presentations, sharing their research findings. Wang Yuhao and Fu Xiangyu from the Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, received the Outstanding Poster Award at the sub-conference.

The report presented at this conference was truly outstanding, and the atmosphere in the venue was deeply scholarly. The audience actively asked questions and engaged in lively discussions, enabling the participants to gain rich exchanges and valuable insights. This has greatly promoted the advancement and innovation of academic standards and technological development in China’s fields of microelectronics and optoelectronic materials.