LiTaO3 SLT (Near-stoichiometric LiTaO₃)
Grade
Pick when a higher Curie point, much lower coercive field for periodic poling, and lower optical damage/absorption are needed.
Values for the SLT condition
Other LiTaO3 tempers and conditions
LiTaO3 is listed in 6 conditions; see the grade overview at LiTaO3.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
CLTDefault Congruent-composition single crystal, poled optical/general grade | Standard Czochralski congruent crystal (Li/(Li+Ta) ≈ 0.485) — default for general piezo, EO and pyroelectric use. | — | — | — | 900 HV | 5 W/m·K |
36° rotated Y-cut, X-propagation SAW wafer | Classic high-coupling shear-horizontal SAW cut for RF filters and duplexers up to a few GHz. | — | — | — | 900 HV | 4 W/m·K |
42° rotated Y-cut, X-propagation leaky-SAW wafer | Preferred cut for low-loss leaky-SAW ladder filters in mobile RF front-ends; also base for POI/bonded thin-film SAW. | — | — | — | 900 HV | 4 W/m·K |
SLTThis page Near-stoichiometric LiTaO₃ | Pick when a higher Curie point, much lower coercive field for periodic poling, and lower optical damage/absorption are needed. | — | — | — | 920 HV | 5 W/m·K |
Black (chemically reduced) Z-cut LiTaO₃ | Reduced, opaque and semiconducting-surfaced material: bleeds off pyroelectric charge and absorbs IR directly — standard for pyroelectric detectors and thermal sensors. | — | — | — | 930 HV | 5 W/m·K |
Z-cut clear wafer | Use for pyroelectric IR detectors, THz emitters and electro-optic elements where optical clarity along c is required. | — | — | — | 940 HV | 5 W/m·K |
What is LiTaO3 SLT?
LiTaO3 SLT is LiTaO3 in the SLT grade — pick when a higher Curie point, much lower coercive field for periodic poling, and lower optical damage/absorption are needed. The elastic modulus is 228 GPa (33.1 Msi). LiTaO3 SLT has a density of 7.45 g/cm³ (0.269 lb/in³), heavier than 72% of ceramic grades. It melts at 1,650°C (3,002 °F). CLT is the default condition FabDigit quotes; SLT is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 90/100, better than 78% of ceramic grades
Limitations
- High embodied carbon — 120 kg CO₂/kg, worse than 99% of ceramic grades
- Low fracture toughness — 0.95 MPa·√m (0.865 ksi·√in), worse than 93% of ceramic grades
LiTaO3 SLT properties
Typical room-temperature values for LiTaO3 SLT; 12 are specific to this condition. Other listed values are LiTaO3 reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical5
LiTaO3 SLT has a density of 7.45 g/cm³ (0.269 lb/in³), heavier than 72% of ceramic grades. It melts at 1,650°C (3,002 °F).
Mechanical10
The elastic modulus is 228 GPa (33.1 Msi).
Thermal5
LiTaO3 SLT is rated for continuous service to 560°C (1,040 °F). It conducts heat at 4.7 W/m·K (2.72 BTU/hr·ft·°F), worse than 62% of ceramic grades. Thermal expansion is 16.1 µm/m·K (8.94 µin/in·°F).
Electrical4
LiTaO3 SLT has an electrical resistivity of 1×10¹¹ Ω·m.
Chemical & Environmental2
Corrosion resistance is very good (70/100), worse than 59% of ceramic grades.
Sustainability4
Producing a kilogram of LiTaO3 SLT takes about 1,800 MJ of energy and emits 120 kg of CO₂ — more than 99% of ceramic grades. Typical recycled content is 5%.
Manufacturability2
LiTaO3 SLT's machinability is not recommended (10/100, better than 76% of ceramic grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with LiTaO3 SLT
Is LiTaO3 easy to machine?
Diamond wire/ID sawing, lapping and CMP only — no conventional cutting; keep heating/cooling below ~2 °C/min because pyroelectric charge and 4:1 CTE anisotropy crack wafers.
Can LiTaO3 be welded?
Not weldable; joined by direct/plasma-activated wafer bonding to Si or quartz (POI/TC-SAW stacks), or by low-stress adhesives and solders.
Can LiTaO3 be formed, bent or molded?
Shape is set by Czochralski growth of the boule, single-domain poling near the Curie point, then orientation-controlled slicing (±0.05° cut-angle tolerance for SAW).
What surface finishes work on LiTaO3?
CMP to <0.5 nm Ra with sub-nm TTV for photolithography; HF etch reveals domains; Al or Ti/Au IDT metallization sputtered, with anti-reflection coatings for optical parts.
LiTaO3 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Li2Ocongruent melt ≈ 48.5 mol% Li2O; SLT grade ≈ 50 mol% | 12.4 – 12.9 | 12.7 |
| Fetypical trace-impurity limit in device-grade crystal | ≤ 5×10⁻⁴ | — |
| Nbresidual Nb from Ta2O5 feedstock | ≤ 0.05 | — |
| Ta2O5≈ 87.3 wt%; Ta 76.7 wt%, O 20.4 wt%, Li 2.9 wt% on an elemental basis | balance | — |
LiTaO3 SLT — frequently asked
What is LiTaO3 SLT used for?
LiTaO3 SLT is typically used for SAW filters, pyroelectric IR detectors and frequency control devices. In short: higher-temperature SAW crystal; pyroelectric detector standard; crack-prone on thermal ramps.
Is LiTaO3 SLT easy to machine?
Not especially — machinability is rated not recommended (10/100, better than 76% of ceramic grades). Diamond wire/ID sawing, lapping and CMP only — no conventional cutting; keep heating/cooling below ~2 °C/min because pyroelectric charge and 4:1 CTE anisotropy crack wafers.
Can LiTaO3 SLT be welded?
Not weldable; joined by direct/plasma-activated wafer bonding to Si or quartz (POI/TC-SAW stacks), or by low-stress adhesives and solders.
What surface finishes work on LiTaO3 SLT?
CMP to <0.5 nm Ra with sub-nm TTV for photolithography; HF etch reveals domains; Al or Ti/Au IDT metallization sputtered, with anti-reflection coatings for optical parts.
Can LiTaO3 SLT be formed, bent or molded?
Shape is set by Czochralski growth of the boule, single-domain poling near the Curie point, then orientation-controlled slicing (±0.05° cut-angle tolerance for SAW).
What is the maximum service temperature of LiTaO3 SLT?
LiTaO3 SLT is rated for continuous use to about 560°C (1,040 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Properties of Lithium Niobate / Lithium Tantalate (EMIS Datareviews) — INSPEC/IEE (2002)
- Landolt-Börnstein, Group III: Ferroelectrics and Related Substances — Springer (2002)
- LiTaO3 single-crystal wafer specifications (SAW / optical / black grades) — Yamaju Ceramics / CETC / Fujian crystal producers (2024)
- GB/T (industry wafer spec practice) — SAC/GB (2019)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.