Introduction
The semiconductor industry is the backbone of modern-day technology, powering everything from smart phones to artificially intelligent computers. As device sizes shrink and performance requirements expand, materials used in the semiconductor production process must be subjected to more demanding needs. High-purity Cr sputtering targets are now the focal material of this technology enabling high-toughness thin films, electrical conductivity, and corrosion resistance to be deposited. The main content of this report is about chromium sputtering targets’ real application in semiconductors production, with emphasis on how they make it possible to overcome industry challenges and stimulate innovation.
Key Properties at a Glance
The distinctive properties of Chromium render it an excellent material for thin-film deposition in semiconductor manufacturing. These include:
- High Hardness and Wear Resistance: Chromium thin films are endowed with excellent mechanical strength, ideal for wear-resistant coatings.
- Resistance to Corrosion: Chemical resistance to degradation and resistance to oxidation of Chromium ensure long-term reliability.
- Conductivity: Conductivity of Chromium makes it ideal for conductive layers and interconnects.
- High Purity: The purity level of 99.99% and higher ensures defect-free films, which are crucial in semiconductor operation.
With their unique properties, they can deposit thin films that can enhance the performance, reliability, and lifetime of the semicomnductor devices. Here, we discuss their use in three broad applications: diffusion barriers, reflective coatings, and functional thin films.
1. Diffusion Barriers
The Challenge: Copper is the preferred material for interconnects in sophisticated semiconductor devices due to its high conductivity. However, copper atoms tend to migrate into adjacent layers, causing electrical leakage and device failure.
The Solution: Chromium sputtering targets are employed to deposit thin chromium-based diffusion barrier layers to prevent copper migration. The layers act as a stable interface between copper and the adjacent material, preserving the integrity of the interconnect structure.
Applications and Benefits
- Integrated Circuits (ICs): Chromium diffusion barriers find widespread use in IC technology for the reliability of metal interconnects, particularly in data center and AI chips of high performance.
- Electromigration Resistance: The low electromigration potential owing to the high melting point and stability of Chromium helps reduce interconnect degradation with time.
Core Benefit: By blocking copper diffusion, chromium thin films enhance the life and reliability of semiconductor devices to automotive electronic and aerospace needs.
2. Reflective Coatings
The Challenge: Optical components in semiconductor devices, such as photolithography tools and imaging sensors, require highly reflective coatings to achieve optimal management of light. Previously used materials are generally not adequate regarding durability or reflectivity for complex applications.
The Solution: Chromium sputtering targets are used to deposit reflective thin films that have good optical and mechanical properties. The inherent reflectivity and toughness of Chromium make it the ideal material for optical coatings to be used during semiconductor manufacturing.
Applications and Benefits
- Photolithography Systems: Photomasks in photolithography systems are made of a reflective chromium coating that serves to define fine features on semiconductor wafers. These coatings have precise light transmission and reflection characteristics and support high-order lithography techniques like EUV (extreme ultraviolet) lithography.
- Imaging Sensors: Thin Chromium films promote camera sensor and optical detector efficiency by providing highest light reflection and lowest energy loss.
Core Advantage: Highly reflective coatings of Chromium give increased efficiency to optical systems that can then reduce size and maximize semiconductor devices.
3. Functional Thin Films
The Challenge: As the technology of semiconductors develops, thinner films possessing specific properties like wear resistance, chemical stability, or conductivity are required. Traditional materials cannot fulfill these diverse requirements.
The Solution: Chromium sputter targets enable the deposition of beneficial thin films with desired properties that are optimized for a specific application. Chromium can be alloyed to create compounds like chromium nitride (CrN), chromium carbide (CrC), and chromium oxide (Cr₂O₃), each with some special advantage.
Applications and Benefits
- Protective Coatings: Chromium nitride thin films are used as protective coatings of semiconductor devices and provide wear resistance and chemical stability. Protective coatings find particular applications in hostile environments, e.g., motor vehicle and industrial environments.
- Conductive Layers: Thin chromium films are used as conductive coatings in some semiconductor devices, where they provide superior electrical properties and adhesion.
- Specialized Applications: Thin chromium oxide films are used in gas sensors and other specialty products, whose stability and sensitivity enhance performance.
Key Advantage: Flexibility of chromium thin films allows manufacturers to address a wide range of problems, from making devices more resilient to developing new function.
Emerging Applications
In addition to their traditional semiconductor uses, chromium sputtering targets are now finding new and new uses in emerging technologies. Among these are:
Flexible Electronics: Chromium thin films are being investigated for flexible displays and wearables, where their mechanical strength and electrical conductivity enable new design flexibility.
Energy Storage: Chromium coatings increase the efficiency and shelf life of next-generation batteries and fuel cells.
Medical Devices: Biocompatibility and corrosion of Chromium make it suitable for medical implants and thin-film sensors.
Conclusion
High-purity chromium sputtering targets are an enabling technology for the growth of the semiconductor industry, resolving actual issues in diffusion barriers, optical films, and functional thin films. Their outstanding characteristics—high hardness, corrosion resistance, and electrical conductivity—render them essential for the fabrication of high-quality, high-performance devices. With increasingly growing semiconductor performance and miniaturization, chromium sputtering targets will remain a basis for innovation, making value in many applications.
Visit Stanford Advanced Materials’ homepage to see more sputtering target products.
