Lanthanum aluminate (LaAlO3) single crystal is currently the most important industrialized, large-size single crystal material for high-temperature superconducting thin film substrates. It is grown by the Czochralski method, and single crystals and substrates with a diameter of 2 inches and larger can be obtained. It matches well with high-temperature superconducting materials and lattices such as YBaCuO, has low dielectric constant and low microwave loss, so it is suitable for making high-temperature superconducting microwave electronic devices (such as high-temperature superconducting microwave filters in telecommunication). There are huge reality and potential application prospects.
| Main performance parameters | ||
| Crystal structure | M6（normal temperature） | M3（>435℃） |
| Lattice constant | M6 a=5.357A c=13.22 A | M3 a=3.821 A |
| Melting point（℃） | 2080 | |
| Density | 6.52（g/cm3） | |
| Hardness | 6-6.5（mohs） | |
| Thermal expansion coefficient | 9.4x10-6/℃ | |
| Dielectric constants | ε=21 | |
| Secant loss（10ghz) | ～3×10-4@300k,～0.6×10-4@77k | |
| Color and appearance | To anneal and conditions differ from brown to brownish | |
| Chemical stability | Room temperature is not dissoluble in minerals, the temperature is greater than 150 ℃ in soluble h3po4 | |
| Characteristics | For microwave electron device | |
| Growth method | Czochralski method | |
| Size | 10x3，10x5，10x10，15x15，，20x15，20x20， | |
| Ф15,Ф20，Ф1″，Ф2″,Ф2.6″ | ||
| Thickness | 0.5mm，1.0mm | |
| Polishing | Single-sided or double-sided | |
| Crystal orientation | ＜100＞ ＜110＞ ＜111＞ | |
| Crystal plane orientation accuracy | ±0.5° | |
| Edge orientation accuracy | 2°（Special requirements can reach within 1°） | |
| Bevel wafer | According to specific requirements, wafers with edge-oriented crystal planes inclined at a specific angle (inclination angle 1°-45°) can be processed | |
| Ra: | ≤5Å（5µm×5µm） | |
| Package | Class 100 clean bag, Class 1000 super clean room | |
