Technical development and application of high performance high temperature and high pressure two-sided top press

As an important industrial and scientific research equipment, double-sided top press has a wide range of application prospects under high temperature and high pressure environment, with the continuous progress of technology and market demand, the application field of double-sided top press continues to expand, in addition to the traditional diamond synthesis, but also in the field of geosciences, physics, new material synthesis has many applications. This report gives an overview of the application of double-sided top press in the synthesis of superhard materials and other related fields. The design and manufacturing technology innovation of new high temperature and high pressure double-sided top press are put forward. Combined with the problems facing the development of double top press, the future development direction of domestic double top press is prospected.

Urgent demand for special diamond anvil in ultra-high pressure research

Pressure is an independent thermodynamic parameter that is equally important with temperature and composition. The use of pressure can effectively regulate the atomic distance, crystal structure, carrier concentration, and even change the electronic structure, elemental valence state, etc. in materials, resulting in excellent performance and novel physical phenomena that exist under normal pressure conditions under high pressure. Moreover, the higher the pressure, the more diverse new phenomena can be observed and the more new materials can be obtained, thus becoming a powerful driving force for us to constantly break through the pressure limit. Diamond is the hardest known natural material with high yield strength, and the anvil made from it is currently the only static high-pressure device that can provide a pressure greater than 150GPa. However, the fracture toughness is poor and it is easy to undergo cleavage along the crystal plane direction. These two factors combined determine that the ultimate pressure of diamond on the anvil is 400 GPa. The only way to break through this pressure bottleneck is to find materials with higher hardness and toughness to replace single crystal diamond as anvil material, in order to enable humanity to explore major scientific problems and mysteries under higher pressure.

High power laser technology and application based on optical grade diamond

High power laser sources play a crucial role in the development of industries such as national defense, aerospace, remote sensing, and quantum information. Optical grade diamond has become an ideal material for the new generation of high-power lasers due to its wide spectral transmission range, high nonlinear gain coefficient, high thermal conductivity, and high optical damage threshold. Our team has been committed to the research of high-power diamond laser technology and its applications for a long time. This report will focus on exploring the demand for optical grade diamond in the laser field and how to develop high-power laser systems with narrow linewidth, high coherence, and low noise characteristics by combining nonlinear optical effects such as stimulated scattering, based on the team's achievements. In addition, the report will further analyze the scientific issues of diamond lasers in spectral narrowing, gain medium optimization, and cascade scattering control, demonstrating effective methods for improving laser stability and beam quality. In the future, by further optimizing the performance of diamond materials and laser design, this technology is expected to achieve wider applications in the field of high-power lasers, promoting technological progress in multiple fields.

Research on the Preparation and Application of Conductive Diamond Electrode Materials

In the field of functional diamond, conductive diamond is a very important electrode material. In addition to excellent mechanical properties, it has extremely stable physical and chemical properties in electrolyte solutions, high oxygen evolution potential, and a wide electrochemical potential window. It plays an important role in electrochemical synthesis and electrocatalytic oxidation. Secondly, conductive diamond has extremely low electrochemical capacitance and exhibits low background current, making it an important electrode material for electrochemical sensing. This report focuses on the research of pore structure construction and large-scale synthesis of boron doped diamond electrode materials based on element doping to achieve conductivity, as well as their application progress in electrochemical sensing and electrocatalytic oxidation fields. In addition, this report also introduces the structural construction and interface analysis research of two diamond/graphite electrode materials based on CVD technology sp2 carbon hybridization to achieve conductivity, as well as their application exploration research in electrochemical sensing, electrocatalysis, and electrochemical energy storage fields.

Application of Diamond Room Temperature Bonding Technology in Semiconductor Power Devices

In high-power operation, the performance, stability, and service life of semiconductor devices are limited by the self heating effect, mainly due to insufficient thermal management. Due to its superior thermal conductivity, diamond is widely studied as a potential heat dissipation material for power devices GaN HEMTs. There are currently two main technological routes for integrating diamond with GaN HEMTs. The first method is to deposit diamond on the exposed GaN surface after removing silicon from the GaN on Si substrate, and use a dielectric transition layer (such as SiNx or AlN). Although this method has achieved 4-inch GaN on diamond wafers, it faces challenges. The lower thermal conductivity of the transition layer results in significant thermal resistance, while the diamond deposited on this layer typically exhibits poor crystal quality, limiting its thermal performance. The second method is to use an adhesive layer such as amorphous silicon to bond GaN to the diamond substrate after removing the silicon on the GaN on Si substrate. However, due to the concept of "equipment first" manufacturing, which involves bonding with diamond only after the equipment is manufactured, the application of this GaN on diamond structure in large-diameter wafers is challenging. A more promising solution is to transfer AlGaN/GaN/3C SiC thin films grown on silicon substrates onto diamond, thereby obtaining AlGaN/GaN HEMTs/3C SiC on diamond. This configuration exhibits superior heat dissipation performance compared to GaN on 4H SiC and GaN on Si, with the 3C SiC/diamond interface displaying excellent thermal stability and conductivity. Our ongoing work focuses on transferring AlGaN/GaN/3C SiC thin films grown on silicon substrates to large-sized polycrystalline diamond substrates to produce low-cost, high heat dissipation GaN devices. Meanwhile, we are also conducting in-depth research on interface structure and thermal boundary resistance to further improve performance and reliability.