Si-Al Target

Core Features

1. Precisely Controllable Composition and Excellent Uniformity

   Adopting vacuum melting or mechanical alloying processes, the Si-Al composition ratio deviation is ≤±1%, and the internal composition uniformity deviation of the target is ≤±0.5%. Full ratio customization (Al content 1%~99%) is supported, and the Si-Al ratio can be precisely adjusted according to film functional requirements to meet the performance needs of different application scenarios.
2. High Density and Stable Sputtering Performance

   Densified by hot isostatic pressing (HIP) or spark plasma sintering (SPS) processes, the target density reaches ≥98.5% with porosity ≤1.5%, effectively reducing particle contamination and arcing during sputtering. It features stable sputtering rate and excellent film deposition uniformity, with a film thickness deviation ＜±3% (for large-area deposition), suitable for continuous industrial production.
3. Strong Adaptability of Multi-Functional Film Properties

   The performance of sputtered Si-Al alloy films can be flexibly adjusted by composition ratio:
   • High-aluminum ratio: Good conductivity and corrosion resistance, suitable for conductive interconnection layers in semiconductor packaging and back electrodes of photovoltaic cells;
   • Medium ratio: Balanced conductivity and mechanical strength, usable as gate electrodes in flat panel displays and buffer layers in flexible electronics;
   • High-silicon ratio: High hardness, high resistivity and excellent optical properties, applicable to decorative coatings and optical reflective films.
4. Customizable Specifications and Bonding Solutions

   Two structural forms are supported: planar targets and rotating targets. Planar targets can be customized into circular (φ50~φ300mm) and rectangular (maximum 1000×500mm) specifications with thickness 5~20mm; rotating targets can be customized with outer diameter φ50~φ300mm and length ≤4000mm. Bonding with oxygen-free copper or molybdenum backing targets is supported, with a bonding strength ≥25MPa, improving target heat dissipation performance and service life.

Technical Parameters (Typical Values)

Application Fields

1. Semiconductor Packaging and Microelectronics

   High-aluminum Si-Al targets are used to deposit conductive interconnection layers and pad protection layers for semiconductor devices, improving device conductivity and electromigration resistance; high-silicon Si-Al targets can serve as passivation layers and isolation layers to ensure device electrical stability.
2. Photovoltaic Cell Manufacturing

   As back electrode materials for crystalline silicon solar cells, replacing traditional pure aluminum electrodes, adjusting the Si-Al ratio improves the contact performance between the electrode and the silicon wafer, reduces wafer cracking caused by thermal expansion mismatch, and enhances cell conversion efficiency and reliability.
3. Flat Panel Displays and Flexible Electronics

   Medium-ratio Si-Al targets are used to prepare gate electrodes and source-drain electrodes for TFT-LCD and OLED panels, with balanced conductivity and mechanical flexibility to meet the bending requirements of flexible display panels; they can also be used as doping layers for transparent conductive films to optimize light transmittance and conductivity.
4. Decorative and Protective Coatings

   High-silicon Si-Al targets are used to deposit wear-resistant decorative coatings on hardware and building decoration materials. The films have high hardness, high gloss and excellent corrosion resistance, and can achieve various appearance effects such as stainless steel-like and aluminum alloy-like finishes.

Preparation Process

1. Raw Material Preparation: Select high-purity silicon powder and aluminum powder of 4N grade or above, or high-purity silicon ingots and aluminum ingots, and remove impurities via vacuum purification.
2. Alloying and Forming:
   • Powder Metallurgy Method: Mix silicon powder and aluminum powder in proportion, form via cold isostatic pressing, then densify via vacuum sintering or hot isostatic pressing;
   • Vacuum Melting Method: Vacuum-melt silicon ingots and aluminum ingots in proportion and cast into target blanks.
3. Precision Machining: Cut, grind and polish the blanks to control target dimensional tolerance, flatness and surface roughness to meet sputtering requirements.
4. Backing Target Bonding (Optional): Composite the Si-Al Target with oxygen-free copper or molybdenum backing targets via brazing or diffusion bonding to improve heat dissipation performance, followed by ultrasonic flaw detection.
5. Quality Inspection and Packaging: Detect composition ratio via X-ray fluorescence (XRF), bonding quality via ultrasonic flaw detection, and dimensional accuracy via laser thickness gauge. Qualified products are vacuum-packaged.

Usage and Storage Recommendations

1. Pre-Treatment: Before sputtering, vacuum-bake the target at 150~250℃ for 2~4 hours to remove surface-adsorbed moisture and organics; avoid long-term exposure to air to prevent oxidation of aluminum components.
2. Sputtering Parameters: Magnetron sputtering is recommended, with a vacuum degree ≥5×10⁻⁴ Pa, high-purity argon as the working gas, and a sputtering power density of 3~8 W/cm². Adjust parameters according to target composition and size to ensure uniform film composition.
3. Storage Conditions: Seal and store in a dry, clean vacuum package, with storage temperature 5~30℃ and relative humidity ≤40%. Avoid moisture, dust contamination and severe collision. The shelf life is 12 months.