What Are ZTA Ceramic Substrates?
ZTA ceramic substrates are insulating ceramic base plates made by adding zirconia particles into an alumina matrix. The alumina phase provides electrical insulation, chemical stability and dimensional control, while the zirconia phase improves fracture toughness and helps reduce edge chipping around holes, slots and scribed outlines.
For engineers working with thick-film circuits, heater patterns, sensor carriers or LED/UV modules, ZTA is often selected when standard alumina is easy to chip during laser drilling, handling or assembly, but full zirconia is not required.
Why Use ZTA Instead of Standard Alumina?
| Buyer Concern | Standard Alumina | ZTA Ceramic Substrate | Selection Meaning |
|---|---|---|---|
| Edge chipping around holes | Moderate risk on thin or micro-featured parts. | Better edge toughness and crack resistance. | Better for vias, slots and scribed outlines. |
| Electrical insulation | Strong. | Strong. | Both can work for insulating carriers. |
| Surface preparation | Mature and cost-effective. | Suitable for ground, lapped and print-ready surfaces. | ZTA is useful when print quality and edge integrity both matter. |
| Thermal conductivity | Usually higher than zirconia. | Similar to high-grade alumina in many substrate uses. | Suitable for medium-power modules, not a replacement for AlN in high heat-spreading designs. |
| Cost | Usually lower. | Higher than standard alumina. | Use ZTA when chipping, strength or yield loss justifies the upgrade. |
ZTA Substrates Advantages
- Edge integrity on micro-features — reduced chipping on laser-drilled vias/slots.
- Print-ready surface — controlled Ra and flatness for screen printing and bonding.
- Dimensional stability — consistent thickness and geometry across batches.
- White/reflective option — uniform appearance for optical/LED modules.
- Traceable cleanliness — cleaned, bagged, labeled for immediate line use.
ZTA Ceramic Substrate Properties
| Property | Unit | Alumina (99%) | ZTA (Zirconia Toughened Alumina) | Y-TZP Zirconia |
| Fracture Toughness (KIC) | MPa·m¹⁄² | 5 | 7 – 9 | 6 – 10 |
| Hardness (HV10) | GPa | 8.9 | 9 – 10 (≈ 90 HV) | 12 – 14 |
| Flexural Strength | MPa | 400 | 650 – 800 | 800 – 1200 |
| Density | g/cm³ | 3.9 | 4.0 – 4.3 | 6.0 |
| Relative Wear Rate | — | 1.0 | 0.45 – 0.55 | 0.2 |
| Thermal Expansion Coefficient (RT – 800 °C) | ×10⁻⁶ /K | 8.0 | 8.5 – 9.0 | 10 – 11 |
| Thermal Conductivity (RT) | W/m·K | 25 | 22 – 24 | 2 – 3 |
| Maximum Working Temperature | °C | 1600 | 1450 – 1500 | 1000 – 1200 |
| Dielectric Strength | kV/mm | 12 | 11 – 13 | 9 – 11 |
| Surface Roughness (Ground face) | µm Ra | 0.4 – 1.2 | 0.3 – 0.8 | 0.2 – 0.6 |
| Flatness (after grinding) | mm/300 mm | ≤ 0.4 | ≤ 0.3 | ≤ 0.2 |
Specifications of Zirconia Toughened Alumina Substrates
| Item | Length（mm） | Width（mm） | Thickness（mm） | Purity (Al₂O₃+ZrO₂) |
| AT-ZTA-CS001 | 10 | 10 | 0.5 | 74%+23.5% |
| AT-ZTA-CS002 | 10 | 10 | 1 | 74%+23.5% |
| AT-ZTA-CS003 | 15 | 11 | 1.5 | 74%+23.5% |
| AT-ZTA-CS004 | 18 | 13 | 1.5 | 74%+23.5% |
| AT-ZTA-CS005 | 20 | 20 | 2 | 74%+23.5% |
| AT-ZTA-CS006 | 20 | 20 | 2 | 74%+23.5% |
| AT-ZTA-CS007 | 25 | 25 | 1 | 74%+23.5% |
| AT-ZTA-CS008 | 30 | 30 | 0.5 | 74%+23.5% |
| AT-ZTA-CS009 | 30 | 30 | 1 | 74%+23.5% |
| AT-ZTA-CS010 | 30 | 30 | 2 | 74%+23.5% |
| AT-ZTA-CS011 | 35 | 35 | 1 | 74%+23.5% |
| AT-ZTA-CS012 | 40 | 40 | 1 | 74%+23.5% |
| AT-ZTA-CS013 | 40 | 40 | 3 | 74%+23.5% |
| AT-ZTA-CS014 | 50 | 30 | 0.5 | 74%+23.5% |
| AT-ZTA-CS015 | 50 | 50 | 0.5 | 74%+23.5% |
| AT-ZTA-CS016 | 50 | 50 | 1 | 74%+23.5% |
| AT-ZTA-CS017 | 50 | 50 | 1.5 | 74%+23.5% |
| AT-ZTA-CS018 | 50 | 50 | 2 | 74%+23.5% |
| AT-ZTA-CS019 | 60 | 60 | 1 | 74%+23.5% |
| AT-ZTA-CS020 | 65 | 35 | 0.5 | 74%+23.5% |
| AT-ZTA-CS021 | 65 | 48 | 1 | 74%+23.5% |
| AT-ZTA-CS022 | 70 | 70 | 1.2 | 74%+23.5% |
| AT-ZTA-CS023 | 70 | 70 | 3 | 74%+23.5% |
| AT-ZTA-CS024 | 76.2 | 76.2 | 1.5 | 74%+23.5% |
| AT-ZTA-CS025 | 80 | 80 | 3 | 74%+23.5% |
| AT-ZTA-CS026 | 80 | 80 | 2 | 74%+23.5% |
| AT-ZTA-CS027 | 80 | 70 | 1.5 | 74%+23.5% |
| AT-ZTA-CS028 | 84 | 84 | 0.8 | 74%+23.5% |
| AT-ZTA-CS029 | 100 | 100 | 0.5 | 74%+23.5% |
| AT-ZTA-CS030 | 100 | 100 | 1 | 74%+23.5% |
| AT-ZTA-CS031 | 100 | 100 | 1.2 | 74%+23.5% |
| AT-ZTA-CS032 | 100 | 100 | 1.5 | 74%+23.5% |
| AT-ZTA-CS033 | 100 | 100 | 2 | 74%+23.5% |
| AT-ZTA-CS034 | 100 | 90 | 1.5 | 74%+23.5% |
| AT-ZTA-CS035 | 100 | 80 | 1.8 | 74%+23.5% |
| AT-ZTA-CS036 | 100 | 75 | 2 | 74%+23.5% |
| AT-ZTA-CS037 | 10-400 | 10-400 | 0.5-2.5 | 74%+23.5% |
Design and RFQ Guidelines for ZTA Substrates
To quote ZTA ceramic substrates accurately, please provide a drawing or sample with the required outline, thickness, hole diameter, slot width, tolerance, flatness or warp requirement, surface roughness target, quantity and downstream process.
For printed heater or sensor substrates, please also indicate whether the surface will be used for thick-film printing, bonding, soldering, DPC preparation, metallization or optical alignment. This helps ADCERAX review the correct surface finish, cleaning method, inspection plan and packaging method before production.
ZTA Ceramic Substrate Packaging
- All ceramic substrates are individually wrapped in anti-static, padded sheets, sealed, and placed in custom-cut foam-lined boxes to ensure maximum protection.
