ST11213 Strontium Aluminate (SrAl2O4) Sputtering Target

Complete Technical Specifications

For detailed evaluation and procurement (Product Code: ST11213).

Technical & Application Notes

1. The Premier Material for Persistent Phosphor Thin Films

SrAl₂O₄, when doped with europium (Eu²⁺) and dysprosium (Dy³⁺), is the benchmark material for long-lasting afterglow phosphors. Sputtering enables the deposition of thin, uniform phosphor films for advanced applications:

• Glow-in-the-Dark Coatings & Safety Signage: Thin films on ceramics, metals, or flexible substrates for emergency pathway marking, watch dials, and decorative items with superior afterglow compared to traditional sulfides.
• Optical Storage & Sensing: The ability to “store” light energy and release it slowly is explored for optical memory devices and stress/strain sensing coatings, where the luminescence intensity changes with mechanical deformation.
• Biomedical Imaging Probes: Nano or micro-particles of SrAl₂O₄:Eu,Dy can be used in bio-labels; thin films are relevant for developing integrated optical sensor platforms.

Target Key: The monoclinic phase and precise control of dopant concentration and oxidation state (Eu²⁺ vs Eu³⁺) in the target are absolutely critical to achieving intense and long-lasting afterglow in the film.

2. High-k Dielectric for Electronic Applications

Undoped or lightly doped SrAl₂O₄ possesses a relatively high dielectric constant, making it suitable for:

• Gate Dielectrics & Capacitors: As a high-k material, it can be used in metal-insulator-metal (MIM) capacitors or as a gate dielectric layer in transistors to reduce leakage current compared to silicon dioxide.
• Protective Passivation Layers: Its chemical and thermal stability makes it an excellent protective coating for sensitive electronic components against moisture and environmental degradation.

3. Protective & Functional Ceramic Coatings

• Thermal Barrier & Environmental Protection: Dense SrAl₂O₄ films offer good resistance to oxidation and corrosion at high temperatures, suitable for coating turbine blades or engine components.
• Transparent Conductive Oxide (TCO) Substrate: As a ceramic substrate with matched thermal expansion, it can be used for growing other functional oxide films.

4. Deposition & Post-Processing Considerations

Sputtering and processing SrAl₂O₄ films require careful control:

• RF Sputtering & Oxygen Control: RF magnetron sputtering is necessary. Reactive sputtering in an Ar/O₂ mix or from an oxide target in pure Ar requires optimization to maintain stoichiometry and the correct Eu valence state (²⁺ for phosphorescence).
• Post-Deposition Annealing: Crystallization and activation of luminescent centers (especially for doped films) almost always require a post-deposition anneal in a controlled atmosphere (often reducing, like N₂/H₂ mix) to convert Eu³⁺ to Eu²⁺ and achieve optimal afterglow.
• Substrate Compatibility: Film adhesion, stress, and crystallinity are highly dependent on substrate material (Si, SiO₂, glass, metal) and temperature.

Quality Assurance

For functional oxide targets like SrAl₂O₄, phase and composition are paramount. Our quality protocol includes:

1. Quantitative X-ray Diffraction (XRD): Guarantees the dominant monoclinic phase and quantifies unwanted secondary phases (e.g., Sr₃Al₂O₆, SrAl₁₂O₁₉, Al₂O₃).
2. Inductively Coupled Plasma (ICP) Analysis: Verifies the precise Sr/Al ratio and quantifies doping element concentrations (Eu, Dy) to within tight tolerances.
3. Density & Microstructure Control: High-density sintering ensures target integrity and stable sputtering. SEM analysis confirms uniform grain structure without excessive porosity.

Why Stanford Advanced Materials (SAM)

• Functional Oxide Specialists: We excel in manufacturing ceramic targets where crystal phase and dopant control define the film’s optical or electronic functionality.
• Phosphor Material Expertise: We understand the critical role of stoichiometry, phase purity, and reducing annealing in achieving persistent luminescence.
• Custom Doping Capability: We can tailor the target with specific rare-earth dopants (Eu, Dy, etc.) and concentrations to meet your research objectives in phosphors or dielectric tuning.

Request More Information

Define Your Functional Oxide Film Goal
To configure the optimal SrAl₂O₄ target, please specify:

1. Primary application (e.g., persistent phosphor film, high-k dielectric, protective coating).
2. If doped: required dopant(s) (e.g., Eu, Dy) and approximate concentration.
3. Target shape, dimensions, and required crystal phase confirmation.
4. Any specific post-deposition processing planned (e.g., annealing atmosphere).