Molybdenum Oxide, MoO3
Molybdenum oxide (MoO3) is a wide-bandgap transition metal oxide supplied as sputtering targets by Infinita Materials for hole-transport interlayers, electrochromic films, and gas-sensing coatings. As the fully oxidised, most chemically stable form of molybdenum oxide, it combines a high work function with strong optical modulation behaviour, properties that make it a standard interlayer material in organic electronics.
| Purity (%) : | >99.9 |
| Dimensions : | Dia. 1”, Thick. 0.125” Dia. 2”, Thick. 0.25” |
Introduction to Molybdenum Oxide
Molybdenum trioxide (MoO₃), particularly the α-MoO₃ phase, crystallises in a layered orthorhombic structure composed of distorted MoO₆ octahedra. It is a wide-bandgap n-type semiconductor with a high work function and defect-tunable electronic properties. Oxygen deficiency produces MoO₃₋ₓ, introducing electronic states that influence conductivity and electrochromic behaviour. RF or reactive DC/pulsed-DC magnetron sputtering enables precise control of film thickness, stoichiometry, and uniformity, including ultrathin layers. Sputtered MoO₃ films are widely investigated as hole-injection and transport layers in OLEDs and organic photovoltaics, electrochromic smart-window and ion-storage devices, and gas or humidity sensors, where controlled interfaces and reversible intercalation chemistry are essential.
FAQs
Question: What is the MoO₃ sputter target used for?
Answer: MoO₃ sputtering targets are used to deposition thin films of molybdenum trioxide (MoO₃) in applications such as electrochromic devices, photocatalysis, gas separation membranes, thin-film transistors, and energy storage devices like supercapacitors.
Question: How is MoO₃ deposited onto substrates?
Answer: MoO₃ is deposited through reactive sputtering in an oxygen-rich environment. In this process, a target of MoO₃ is bombarded by ions, releasing molybdenum and oxygen atoms that deposit onto a substrate as a thin MoO₃ film.
Question: Should MoO3 be sputtered using RF or DC power?
Answer: Stoichiometric MoO3 is an electrical insulator, so ceramic MoO3 targets are typically sputtered using RF power. Many production lines instead use reactive DC or pulsed-DC sputtering from a metallic molybdenum target in an oxygen/argon atmosphere, which gives higher deposition rates and works well for ultrathin interlayer films when oxygen partial pressure is tightly controlled.
Introduction to Molybdenum Oxide
Molybdenum trioxide (MoO₃), particularly the α-MoO₃ phase, crystallises in a layered orthorhombic structure composed of distorted MoO₆ octahedra. It is a wide-bandgap n-type semiconductor with a high work function and defect-tunable electronic properties. Oxygen deficiency produces MoO₃₋ₓ, introducing electronic states that influence conductivity and electrochromic behaviour. RF or reactive DC/pulsed-DC magnetron sputtering enables precise control of film thickness, stoichiometry, and uniformity, including ultrathin layers. Sputtered MoO₃ films are widely investigated as hole-injection and transport layers in OLEDs and organic photovoltaics, electrochromic smart-window and ion-storage devices, and gas or humidity sensors, where controlled interfaces and reversible intercalation chemistry are essential.
Key Properties of Molybdenum Oxide
| Property | Value | Significance |
|---|
| Crystal Structure | Orthorhombic, layered alpha-MoO3 (Mo-O octahedral double layers, van der Waals gap) | Layered anisotropy influences film texture, ion intercalation pathways, and mechanical behaviour of sputtered coatings |
| Optical Bandgap | ~2.9 – 3.3 eV | Wide-bandgap, largely transparent in the visible range, supporting use in optical and electrochromic stacks |
| Work Function | ~5.5 – 6.9 eV (surface- and stoichiometry-dependent) | One of the deepest work functions among common oxides, enabling efficient hole extraction/injection at organic interfaces |
| Electrical Behavior | Wide-bandgap n-type semiconductor; conductivity rises sharply with oxygen sub-stoichiometry (MoO3-x) | Governs whether RF or reactive DC sputtering is preferred and affects as-deposited film conductivity |
| Melting Point | ~802 degC | Moderate thermal stability sets practical limits on target sintering temperature and sustained sputtering power |
| Thermal Conductivity | ~1.2 +/- 0.3 W/m*K | Low thermal conductivity requires controlled, often pulsed or ramped power to avoid target thermal shock and cracking. |
| Electro/Gasochromic Response | Reversible colour change (pale to deep blue) upon Li+/H+ intercalation or exposure to reducing gases | Basis for electrochromic smart-window and gas/humidity sensor applications |
| Sputtering Behavior | RF or pulsed-DC sputtering of ceramic MoO3 target, or reactive DC sputtering from metallic Mo in O2/Ar | Ceramic target gives direct stoichiometric MoO3 deposition; reactive Mo sputtering offers higher rates but needs tighter O2 partial-pressure control to avoid sub-oxide phases. |
Types & Grades of Molybdenum Oxide
Molybdenum 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 (IN-Mo-01) | 99.9% (3N) | 1 in diameter x 0.125 in thick; stocked size for lab-scale RF sputtering and process development |
| Standard Catalogue Disc (IN-Mo-02) | 99.9% (3N) | 2in diameter x 0.25in thick; common size for small pilot-line deposition systems |
| High-Purity Grade | 99.99% – 99.999% (4N – 5N) | Reduced metallic and oxide impurities for hole-injection layers and electrochromic films sensitive to trace contamination |
| Large-Format / Custom Target | 99.9% – 99.99% | Rectangular and oversized round targets machined to specification for production coaters and roll-to-roll lines |
| Bonded Assembly | 99.9% – 99.99% | MoO3 target bonded to a copper or aluminium backing plate for improved thermal management under sustained sputtering power |
Applications of Molybdenum Oxide
Sputtered films of Molybdenum 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 |
|---|
| Display and Lighting (OLED) | Hole-injection and hole-transport interlayers | High work function of MoO3 lowers the hole-injection barrier at the anode/organic interface, reducing OLED drive voltage. |
| Organic Photovoltaics | Anode buffer / interconnecting layers in tandem cells | Deep work function and band alignment improve hole extraction and reduce recombination losses at the electrode interface |
| Smart Glass / Architectural Glazing | Electrochromic device stacks | MoO3 serves as an active or counter-electrode layer that reversibly changes optical transmittance under applied bias. |
| Sensors | Gas and humidity sensing films | Reversible intercalation and defect chemistry give MoO3 films strong, tunable sensitivity to reducing gases and humidity. |
| Energy Storage | Thin-film Li-ion battery cathode and electrode layers | Layered structure supports reversible lithium intercalation, a mechanism directly relevant to thin-film battery electrodes |
| Catalysis and Coatings | Precursor and functional layers for molybdenum-based catalytic and protective coatings | Controlled MoO3 stoichiometry supports downstream reduction to catalytically active molybdenum oxide and carbide phases. |
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 Molybdenum 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
What is the MoO₃ sputter target used for?
MoO₃ sputtering targets are used to deposition thin films of molybdenum trioxide (MoO₃) in applications such as electrochromic devices, photocatalysis, gas separation membranes, thin-film transistors, and energy storage devices like supercapacitors.
What is the typical purity of MoO₃ sputter targets?
The pure grade of MoO₃ sputter targets generally ranges between 99.95% and 99.999%. Higher purity levels will ensure better film quality and performance, particularly in sensitive electronic and energy applications.
How is MoO₃ deposited onto substrates?
MoO₃ is deposited through reactive sputtering in an oxygen-rich environment. In this process, a target of MoO₃ is bombarded by ions, releasing molybdenum and oxygen atoms that deposit onto a substrate as a thin MoO₃ film.
Should MoO3 be sputtered using RF or DC power?
Stoichiometric MoO3 is an electrical insulator, so ceramic MoO3 targets are typically sputtered using RF power. Many production lines instead use reactive DC or pulsed-DC sputtering from a metallic molybdenum target in an oxygen/argon atmosphere, which gives higher deposition rates and works well for ultrathin interlayer films when oxygen partial pressure is tightly controlled.
Molybdenum Oxide, MoO3
Used in Various Industries
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