CuGa sputtering targets (copper-gallium alloy targets) are core materials used to fabricate the absorber layer of Copper Indium Gallium Selenide (CIGS) thin-film solar cells. Typically manufactured from high-purity copper and gallium, they function primarily by depositing a copper-gallium metal precursor layer via magnetron sputtering, which is subsequently selenized to form the CIGS light-absorbing layer.

📌 Basic Specifications

‌Elemental Composition‌: Cu + Ga; common alloy ratios include CuGa25, CuGa27, and CuGa30. Ga content can be adjusted within the 30–68 at% range, and other compositions can be customized.

‌Purity‌: Typically 4N (99.99%) or 5N (99.999%).

‌Shape‌: Planar targets, rotary targets, and custom shapes; rotary targets are often used for continuous, stable mass production.

‌Typical Density‌: >8.4 g/cm³ (4N grade).

‌Standard Dimensions‌: Planar targets (e.g., Φ500×30 mm), rotary targets (lengths up to 3000 mm); other dimensions available upon request.

‌Appearance‌: Golden yellow or silvery-white.

🎯 Key Applications

‌CIGS Thin-Film Solar Cells‌: This is the primary application for CuGa targets. By sputtering a CuGa/In stacked metal precursor layer followed by selenization to form the CIGS absorber layer, the resulting cells offer advantages such as low cost, excellent low-light performance, and high photoelectric conversion efficiency.

‌Semiconductors and Electronic Devices‌: Used to fabricate high-performance semiconductor devices (such as field-effect transistors) and functional thin films, leveraging the alloy's good electrical and thermal conductivity.

‌Optical Coatings‌: Used in the production of functional thin films, such as anti-corrosion and anti-reflective coatings.

‌Magnetic Recording Materials‌: Used in magnetic recording media to enhance data storage density and read/write speeds.

 🏭 Preparation Process

Preparation methods: CuGa targets can be produced via Spark Plasma Sintering (SPS) or cold spraying; the CuGa₂ phase is softer than CuGa, facilitating the production of defect-free targets that exhibit uniform sputtering characteristics. Melting is also a commonly used production route.

⚠️ Selection Considerations

The Ga content in the target directly affects the bandgap and optoelectronic properties of the resulting CIGS thin film; the composition ratio should be determined based on the target solar cell efficiency.

When purchasing, it is recommended to clearly specify technical requirements—such as purity, dimensions, tolerances, and bonding methods—and to confirm the delivery schedule with the supplier.