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Substrates for Thin Films

We are pleased to offer a wide range of single crystal substrates with perovskite structure for making high quality High Tc films. We have sold these substrates to customers all over the globe, gaining a reputation for fine quality.

Standard Tolerances for All Crystals

In addition to the detailed specifications included on the following pages for the most popular substrates, we offer the following standard specifications for all crystals:

    Boules are X-ray oriented and guaranteed within .5 degrees from designated plane. Back reflection Laue photo can be supplied if necessary.

    Standard Dimensional Tolerance: +/- .1mm (0.004")

    Capability Upon Request (extra fee): +/1 .05mm (.002")

    Standard Thickness Tolerance: +/- .05mm (.002")

    Capability upon request (extra fee): +/- .01mm (.0004")

    Surface Flatness: within 1 micron across 2" dia. surface on expitaxial polish.

    Surface Roughness: within 15 Angstroms - normally 10 Angstroms.

    Epitaxial Polish: On "One Side Polished" substrates, the back side is fine ground to 40 microns. On "Two Side Polished", both sides are epitaxially polished.

PLEASE NOTE: We absolutely guarantee no chipped edges, clipped corner, or unsquare dimensions.

We can also provide custom sizes and off angle or edge oriented substrates at a small additional charge.

ADDITIONAL NOTE: Because of the relatively small size of these substrates we recommend that they be shipped via NEXT DAY AIR SERVICE in order to provide additional traceablilty.

Magnesium Oxide Single Crystal Substrates

Material Parameters - Substrate Parameters -

Formula: MgO Orientation: (100), (110)

Substrates are edge oriented, other Orientations available on request.

Physical Properties:

Structure: Cubic a=0.4203 nm Tolerance of Orientation: max 30',

Twin Structure: Twinfree typical <20'

Density: 3.58 g/cm3

Melting Point: 2800oC

Thermal Expansion: 8 x 10-6 K-1

Dielectric Constant: 8.1

Loss Tangent (10 GHz): 9 x 10-3

Lanthanum Aluminate Single Crystal Substrates

Material Parameters - Substrate Parameters -

Formula: LaAlO3 Orientation: (100)

Other Orientations available on request

substrates are edge oriented

Physical Properties:

Structure: Rhomboedric a=0.5377 nm Tolerance of Orientation: max 30'

Phase Transition: < 500oC typical <20'

Twin Structure: Twins//to the (100)-planes of the pseudocubic cell

Density: 6.51 g/cm3

Melting Point: 2180oC

Thermal Expansion: 10-5 K-1

Dielectric Constant approx. 24

Loss Tangent: 6 x 10-5 at 77K

3 x 10-4 at 300K

Strontium Titanate Single Crystal Substrates

Material parameter - Substrate parameter -

Formula: SrTiO3 Orientation: (100),(110)

Other orientations available on request

substrates are edge oriented

Physical Properties:

Structure: Cubic a = 0.3905 nm Tolerance of orientation: max 30'

Twin Structure: twinfree typical <20'

Density: 5.12 g/cm3

Melting Point: 2080oC

Thermal Expansion: 9 x 10-6 K-1

Dielectric Constant: 300

Loss Tangent: 2 x 10-2

Sapphire Single Crystal Substrates

Material Properties - Substrate Properties -

Formula: Al2O3 Orientation: (0001);(1012);(1102)

Other orientations on request

Physical Properties:

Structure: Hexagonal a=0.477 nm Tolerance of orientation: Max 1o

Twin Structure: twinfree typical <40o

Density: 3.98 g/cm-3

Melting Point: 2052oC

Thermal Expansion: par.c: 5.4 x 10-6 K-1; perp.c: 6.2 x 10-6 K-1

Dielectric Constant: par c: 9.4; perp.c: 11.5

Loss Tangent (10 GHz): par.c.: 3 x 10-5; perp.c.: 8.6 x 10-5