Huanghe Whirlwind launches R&D project for 3-inch and optical-grade CVD polycrystalline diamond films

May 27, Henan Yellow River Whirlwind The joint-stock company announced on the investor relations platform that Huanghe Xuanfeng will begin producing 3-inch diameter and optically graded CVD polycrystalline materials. Diamond Work is underway to develop thin films, and plans are being made to establish a CVD polycrystalline diamond testing center, paving the way for the application of CVD diamond films in fields such as thermal, optical, electrical, acoustic, and electrochemical properties.

        I. What is CVD Polycrystalline Diamond Film?

CVD stands for Chemical Vapor Deposition, which differs from extracting natural materials. Diamonds Alternatively, synthetic diamonds can be produced by simulating the extreme temperature and pressure conditions found deep beneath Earth’s surface (the HTHP method). The process involves introducing a carbon-containing gas, such as methane (CH₄), along with hydrogen (H₂), into a vacuum or low-pressure reaction chamber. A specific energy source—like microwaves, hot filaments, or an electric arc—is then used to excite the gases, creating plasma that breaks down the gas molecules. Under precisely controlled temperature conditions (typically ranging from 800°C to 1200°C) and pressure, carbon atoms or carbon-based groups are deposited, migrated, and rearranged on the surface of a selected substrate—such as a silicon wafer, molybdenum sheet, or even ceramic—ultimately forming a diamond structure.

        Single Crystal vs. Polycrystalline

Single-crystal diamonds feature atoms arranged in a regular, continuous pattern throughout the entire crystal—much like a flawless piece of crystal. They boast exceptional performance but are limited in size (especially large single crystals are incredibly challenging—and time-consuming—to grow—and come at a remarkably high cost).

Polycrystalline diamond films are composed of countless tiny diamond grains—typically ranging in size from nanometers to micrometers—that are tightly packed together, with grain boundaries forming between them. While these grain boundaries can introduce minor variations in certain properties (such as slightly lower thermal conductivity or optical scattering), they effectively address the key limitations of single-crystal diamonds: size constraints and high costs—thus enabling large-scale, customizable production.

CVD polycrystalline diamond films combine the exceptional properties of diamond—such as high hardness, excellent thermal conductivity, and a wide bandgap—with the design flexibility of thin films (e.g., controllable thickness, tailored shapes, and compatibility with various substrates), making them highly valuable for applications across multiple industries.

Yellow River Whirlwind's 2-inch polycrystalline diamond heat sink wafer

     2. Major Application Areas

        1. Optics

Infrared optical windows: Protective windows used in aerospace and military applications for infrared detectors (e.g., missile guidance systems).

Ultraviolet Light-Emitting Devices: Leveraging diamond's wide bandgap property (bandgap width of 5.5 eV), we are developing day-blind ultraviolet detectors and deep-ultraviolet light-emitting diodes (DUV-LEDs).

       2. Semiconductors

Thermal devices: Heat sink materials designed for 5G base station chips and laser diodes (LDs), addressing the thermal challenges of high-frequency components.

Power device substrates: When combined with wide-bandgap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN), they enhance device performance in high-frequency and high-temperature environments.

      3. Biomedicine and Sensors

Biocompatible coatings: Used in implantable medical devices (such as artificial joints), leveraging diamond's chemical inertness and low coefficient of friction.

High-sensitivity sensors: Leveraging nitrogen-vacancy (NV) centers in diamond, we’ve developed nanoscale magnetic field and temperature sensors for applications in bioimaging and quantum computing.

As the "ultimate semiconductor material," diamond continues to see ongoing advancements in its thermal, optical, electrical, and quantum properties. Diamond-based materials—particularly those used for thermal management, optics, mechanics, acoustics, and semiconductors—boast significant advantages and immense growth potential. These materials are already playing a critical role in cutting-edge high-tech industries and the defense sector, making them a new focal point of international competition.

As CVD polycrystalline diamond films mature in manufacturing processes and become more cost-effective, their application scope will continue to expand, potentially playing a pivotal role in the future across industries such as semiconductors, quantum technology, and new energy. Huanghe Xuanfeng has launched an R&D project focused on 3-inch and optical-grade CVD polycrystalline diamond films—a move that not only represents a significant technological breakthrough but also marks a solid step toward domesticating high-end and optically critical materials, injecting cutting-edge scientific and engineering power into "Made in China" initiatives.