Tin Oxide, SnO2
Tin oxide (SnO2) is a wide-bandgap n-type semiconducting oxide supplied by Infinita Materials as a high-purity ceramic sputtering target for thin-film deposition. Also known as tin(IV) oxide or stannic oxide, it combines optical transparency in the visible range with tunable electrical conductivity, making it a workhorse material for transparent conducting films, gas sensors, and protective oxide coatings. Infinita Materials supplies SnO2 targets in standard catalogue sizes and custom geometries for both research and production sputtering systems.
| Purity (%) : | >99.9 |
| Dimensions : | Dia. 1”, Thick. 0.125” Dia. 2”, Thick. 0.25” |
Question: Should SnO2 be sputtered with RF or DC power?
Answer: Undoped SnO2 targets are semiconducting to poorly conductive, so RF magnetron sputtering (or reactive/pulsed-DC sputtering from a metallic or suboxide tin target with oxygen bleed) is typically used to sustain a stable discharge; conventional DC sputtering can struggle with charge build-up on a fully oxidized ceramic target surface.
Question: What sizes are available beyond the standard 1in and 2in catalogue discs?
Answer: Diameters from 1in to 6in and thicknesses of 0.125in and 0.25in are readily available, along with rectangular plates and large-format planar or rotary/cylindrical targets suitable for architectural-glass and display-coating lines. Custom hole drilling, beveling, and grooving can be specified for a given deposition system.
Question: What is the typical lead time for a SnO2 target order?
Answer: Standard catalog sizes in 3N purity are typically the fastest to ship from stock or short-run production; high-purity (4N/5N) grades, bonded assemblies, and custom or large-format geometries require longer lead times for fabrication and quality certification. Specific lead times are confirmed at time of order based on size, purity, and bonding requirements.
Question: Why is SnO2 prone to cracking during sputtering, and how is that managed?
Answer: SnO2 is a hard, brittle ceramic with relatively low thermal conductivity, so localized heating under plasma bombardment can create thermal gradients that lead to cracking. Elastomer bonding to a copper backing plate improves heat dissipation and mechanical compliance, and controlled power ramp-up during sputtering further reduces thermal-shock risk.
Key Properties of Tin Oxide
| Property | Value | Significance |
|---|
| Crystal structure | Tetragonal rutile, space group P42/mnm (No. 136) | Sets the film’s grain orientation and growth texture on glass and crystalline substrates |
| Lattice parameters | a = ~4.74 Angstrom, c = ~3.19 Angstrom | Governs epitaxial and textured growth behaviour relative to common TCO and sensor substrates |
| Optical bandgap | ~3.6 – 4.0 eV (direct) | Wide bandgap keeps sputtered films optically transparent across the visible spectrum. |
| Electrical behavior | Intrinsic n-type semiconductor; resistivity tunable via oxygen vacancies and F/Sb doping | Enables use as both a transparent conducting oxide and a gas-sensitive resistive layer |
| Refractive index | ~1.9 – 2.0 (visible) | Compatible with anti-reflective and multilayer transparent-electrode optical stacks |
| Melting point | ~1630 C | High thermal stability supports elevated-substrate-temperature deposition and post-anneal processing. |
| Target electrical conductivity (bulk ceramic) | Semiconducting to poorly conductive depending on stoichiometry and doping | Most SnO2 target grades require RF or pulsed-DC/reactive magnetron sputtering rather than pure DC |
| Sputtering behavior | Brittle, low-thermal-conductivity ceramic target; susceptible to thermal shock | Favours elastomer bonding and controlled power ramp-up to avoid target cracking during deposition |
Types & Grades of Tin Oxide
Tin Oxide targets are offered in standard catalogue sizes and grades, with custom purity, density, and geometry available for OEM and R&D deposition systems.
| Grade / Form | Typical Purity | Key Features / Uses |
|---|
| Standard catalogue disc (1 in x 0.125in) | 99.9% (3N) | Stock size for R&D chambers and small-tool process qualification |
| Standard catalogue disc (2 in x 0.25in) | 99.9% (3N) | Common size for pilot-line and multi-target research deposition systems |
| High-purity grade | 99.99% – 99.999% (4N – 5N) | Reduced trace-metal content for TCO and semiconductor-grade transparent electrode applications |
| Large-format / custom planar | 99.9% – 99.99% | Rectangular and oversized planar targets for architectural-glass and display-panel coaters; custom hole patterns and grooving available |
| Bonded / rotary assemblies | 99.9% – 99.99% | SnO2 tiles elastomer- or indium-bonded to copper backing plates, or configured as rotary/cylindrical targets for high-throughput in-line coating lines |
Applications of Tin Oxide
Sputtered films of Tin Oxide support demanding roles across research and production applications where this material’s specific structural, electronic, or optical properties are the key requirement.
| Industry | Application | Function |
|---|
| Flat-panel displays and touch screens | Transparent conducting electrode films | Provides an optically clear, electrically conductive layer for pixel electrodes and capacitive touch sensors |
| Architectural and automotive glass | Low-emissivity and solar-control coatings | Fluorine-doped SnO2 (FTO) films reflect infrared heat while transmitting visible light for energy-efficient glazing. |
| Gas sensing | Resistive gas sensor films (CO, NOx, VOC, combustible-gas detection) | Surface oxygen-vacancy chemistry changes film resistance in response to adsorbed target gas species |
| Photovoltaics | Front-contact transparent electrodes on thin-film solar cells | Conductive, transparent SnO2/FTO layers collect current while admitting light to the absorber layer |
| Energy storage | Anode and electrode films for lithium-ion and related battery research | SnO2’s reversible lithium-alloying and conversion reactions support high theoretical capacity anode films |
| Protective and functional coatings | Chemically resistant, transparent barrier films | Chemical inertness and hardness protect underlying substrates while maintaining optical transparency. |
Why Partner with Infinita Materials?
- Technical Depth: in-house quality control with ICP-MS and XRF purity verification, density measurement, and full certificates of analysis on every target.
- Global Logistics: reliable supply from single R&D-scale targets to production-line volumes, with established international shipping.
- Responsive Support: direct access to materials engineers for grade, bonding, and geometry selection, and process-compatibility questions.
Take the Next Step
Infinita Materials fabricates Tin Oxide sputtering targets engineered to the purity, density, and geometry your deposition process requires. Whether the requirement is a standard catalogue target or a custom size, purity, or bonded assembly, our team can help match the right specification to your deposition system. Request a quote or speak with our technical team to discuss your target specification.
Frequently Asked Questions
Should SnO2 be sputtered with RF or DC power?
Undoped SnO2 targets are semiconducting to poorly conductive, so RF magnetron sputtering (or reactive/pulsed-DC sputtering from a metallic or suboxide tin target with oxygen bleed) is typically used to sustain a stable discharge; conventional DC sputtering can struggle with charge build-up on a fully oxidized ceramic target surface.
What sizes are available beyond the standard 1in and 2in catalogue discs?
Diameters from 1in to 6in and thicknesses of 0.125in and 0.25in are readily available, along with rectangular plates and large-format planar or rotary/cylindrical targets suitable for architectural-glass and display-coating lines. Custom hole drilling, beveling, and grooving can be specified for a given deposition system.
What is the typical lead time for a SnO2 target order?
Standard catalog sizes in 3N purity are typically the fastest to ship from stock or short-run production; high-purity (4N/5N) grades, bonded assemblies, and custom or large-format geometries require longer lead times for fabrication and quality certification. Specific lead times are confirmed at time of order based on size, purity, and bonding requirements.
Why is SnO2 prone to cracking during sputtering, and how is that managed?
SnO2 is a hard, brittle ceramic with relatively low thermal conductivity, so localized heating under plasma bombardment can create thermal gradients that lead to cracking. Elastomer bonding to a copper backing plate improves heat dissipation and mechanical compliance, and controlled power ramp-up during sputtering further reduces thermal-shock risk.
Tin Oxide, SnO2
Used in Various Industries
Biomedical
Energy
Aerospace
Automotive
Healthcare
Electronics
