•Good lattice match with perovskite structure superconductors •Stable structure with much less defects than SrTiO3 •Low dielectric constant suitable for microwave or high frequency application
Typical Properties
Chemical Formula
SrLaAlO4
Purity
99.99%
Color
Light Brown
Crystal Structure
Tetragonal
Unit Cell
•a = 3.756 Å •c = 12.636 Å
Density
5.92 g / cc
Melting Point
1650 oC
Thermal Expansion Coeff.
12 ppm / oC
Dielectric Constant
•16.81 at a axis •20.02 at c axis
Loss Tangent (1 MHz, 300 K)
•6 x 104 at a axis •8 x 104 at c axis
Crystal growth Technique
CZ
Maximum as grown. crystal size
30 mm dia x 35 mm length
Standards substrate Size
10 mm x 10 mm x 0.5 mm
Standard Orientation
(100), (001)
Comparison of SrTiO3 - LaAlO3 - SrAlO4 Crystal
Properties/Crystal
SrTiO3
LaAlO3
SrLaAlO4
Structure
Cubic
Rhombohedral at 25 oC : Cubic at > 435 oC :
Tetragonal
Lattice Constant
a = 3.905
a = 3.821 A
a = b = 3.756 A c = 12.636
mismatch to YBCO (a = 3.9)
+0.12 %
-2.0 %
-3.7 %
Dielectric Constant
~ 300
~ 25
~ 17
Grown Method
Vernuil
CZ
CZ
Thermal expansion
10.4 (x10-6 / oC)
10 (x10-6 / oC)
12 (x10-6 / oC)
Melting point
2100 oC
2080 oC
1650 oC
Density
5.175 g/cm3
6.52 g/cm3
5.92 g/cc
Max. Crystal size
30 mm dia.
75 mm dia
35 mm dia
Crystal quality
Wide rocking curve due to dislocation density
Visible twin due to phase transition around 400 oC