Is the alumina dielectric-strength value enough to confirm the working voltage?

No. Dielectric strength describes the ceramic material under specified test conditions, not the voltage rating of the finished module. Ceramic thickness, conductor spacing, pattern geometry, surface condition, operating environment and test method must also be reviewed.

How is the maximum operating temperature determined?

There is no single temperature rating for every metallized alumina substrate. The practical limit depends on the ceramic, metallization route, surface finish, joining system, attached components, exposure time and thermal-cycle conditions.

What can cause the metal layer to separate from the ceramic?

Possible causes include surface contamination, unsuitable metallization, excessive thermal or mechanical stress, poorly designed metal geometry and an assembly process that does not match the substrate stack-up. Project-specific process validation is required.

How should thermal-cycling requirements be specified?

Please define the minimum and maximum temperatures, ramp rate, dwell time, required cycle count, mounting condition, cooling interface and acceptance criteria. Power cycling and environmental cycling should be identified separately.

How should the surface finish be selected?

The finish must match the downstream joining process. Bare copper, nickel, nickel/gold or silver may be considered depending on whether the substrate will be soldered, brazed or wire-bonded.

Can partial or patterned metallization be requested?

Yes. Partial or patterned metallization can be evaluated from a drawing showing the coated areas, keep-out zones, pattern dimensions, alignment requirements, metal thickness and surface finish. Final manufacturability is confirmed during drawing review.

Can ADCERAX evaluate an existing substrate as a second-source option?

Yes. ADCERAX can review the existing drawing, ceramic grade, layer stack-up, metallization route, finish and qualification requirements. The proposed alternative must be evaluated and validated before production approval.

Are ceramic-body properties the same as finished-substrate properties?

No. Density, dielectric strength, thermal expansion and thermal conductivity describe the ceramic body. Metal thickness, adhesion, pattern accuracy and surface finish describe the metallization system. Finished performance also depends on the interfaces, geometry and assembly conditions.

How are tolerances and acceptance criteria confirmed?

Critical dimensions, pattern registration, flatness, edge condition, metal thickness, surface finish and required tests should be defined in the approved drawing or quality document before production.

What should be controlled when moving from prototypes to repeat production?

The approved drawing revision, ceramic grade, metallization process, layer thicknesses, surface finish, critical dimensions, inspection criteria and packaging requirements should be fixed before repeat production. Any material, process or design change should be reviewed before implementation.

Alumina Metalized Ceramic Substrate for Power Electronics

Metalized alumina substrate is a high-performance electronic component made from a small, flat alumina ceramic tile. Alumina is a hard electrical insulator with useful thermal conductivity. A patterned metal layer, usually copper, is bonded to its surface to form conductive paths similar to those on a conventional circuit board.

Alumina Metalized Ceramic Substrate Benefits

Effective thermal management — 96% or 99.6% alumina (Al₂O₃) conducts heat away from components such as IGBTs and LEDs. Actual thermal performance depends on the substrate design, metallization and heat-sink path.
Stable electrical isolation — High dielectric strength and low dielectric loss support high-voltage isolation and signal integrity in high-frequency RF circuits.
Metallization adhesion — DBC, DPC and thick-film processes bond copper or refractory-metal layers to the ceramic. Bond strength and thermal-cycling behavior depend on the selected process and design.
Precision patterning — Laser processing and photolithography support fine circuit traces and spacing down to approximately 30 µm, depending on the process and design.

Metalized Alumina Substrate Properties

Property	Unit	96% Al₂O₃	99% Al₂O₃	99.5% Al₂O₃	99.6% Al₂O₃	99.7% Al₂O₃	99.8% Al₂O₃	99.9% Al₂O₃	99.99% Al₂O₃
Alumina content	%	96	99	99.5	99.6	99.7	99.8	99.9	99.99
Density	g/cm³	3.6-3.75	3.83	3.89	3.91	3.92	3.93	3.94	3.98
Color	–	white	Ivory	Ivory	Ivory	Ivory	Ivory	Ivory	Ivory
Water absorption	%	0	0	–	0	0	0	0	0
Young’s modulus (Elastic modulus)	GPa	300	350	375	356	357	358	359	362
Shear modulus	GPa	–	–	152	–	–	–	–	–
Bulk modulus	GPa	–	–	228	–	–	–	–	–
Poisson’s ratio	–	–	–	0.22	–	–	–	–	–
Compressive strength	MPa	1910	2210	2500	2552	2554	2556	2558	2570
Flexural strength	MPa	260	300	340	345	346	347	348	365
Fracture toughness	MPa·m¹ᐟ²	–	–	4	–	–	–	–	–
Hardness	GPa	14.5	17	17	23	24	25	26	30
Thermal conductivity	W/m·K	20	31	31	31-33	31-33	31-33	31-35	31-35
Thermal shock resistance ΔT	°C	–	–	–	222	223	224	225	228
Maximum use temperature (no load)	°C	1450	1680	≤1750	1755	1760	1765	1770	1800
Coefficient of thermal expansion	10⁻⁶/°C	7.6	7.6	7.6	7.6	7.5	7.5	7.4	7.4
Volume resistivity	Ω·cm	>1×10¹⁴	>1×10¹⁴	>1×10¹⁴	>1×10¹⁴	>1×10¹⁴	>1×10¹⁴	>1×10¹⁴	>1×10¹⁴
Dielectric constant (relative permittivity)	–	9.2	9.5	9.8	9.83	9.84	9.85	9.86	9.92
Dielectric strength	kV/mm	15	19	16.9	23.2	23.4	23.6	23.8	24
Dissipation factor (loss factor @ 1 kHz)	–	–	–	0.0002	–	–	–	–	–

Al₂O₃ Metalized Ceramic Substrate Specifications

Type 1: Rectangular Alumina Metalized Ceramic Substrate

Rectangle Alumina Metalized Ceramic Substrate
Item No.	Length（mm）	Width（mm）	Thickness（mm）	Copper foil thickness (mm)	Copper clad thickness（mm)	Purity（%）
AT-DBC-C001	10	5	0.25	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C002	18	11	0.25	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C003	20	15	0.38	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C004	28	9	0.635	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C005	32	24	0.55	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C006	55	30	6	0.1-0.6	0.035	96
AT-DBC-C007	70	52	0.76	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C008	84	35	1	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C009	103	90	0.635	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C010	127	105	2	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C011	156	84	3	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C012	178	138	5	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-C013	188	138	4.6	0.1-0.6	0.075-0.1	96-99.7

Type 2: Square Alumina Metalized Ceramic Substrate

Square Alumina Metalized Ceramic Substrate
Item No.	Length（mm）	Width（mm）	Thickness（mm）	Copper foil thickness (mm)	Copper clad thickness（mm)	Purity（%）
AT-DBC-Z001	10	10	0.25	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z002	15	15	0.25	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z003	18	18	0.25	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z004	25	25	0.38	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z005	31.5	31.5	0.635	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z006	33	33	0.76	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z007	40	40	0.76	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z008	60	60	1	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z009	72	72	1	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z010	100	100	3	0.1-0.6	0.075-0.1	96-99.7
AT-DBC-Z011	127	127	1	0.1-0.6	0.035	99.7
AT-DBC-Z012	138	138	5	0.1-0.6	0.075-0.1	96-99.7

Metalized Alumina Substrate Packaging

Each metalized ceramic substrate is sealed and placed in an anti-static tray with moisture-resistant packaging. Shock-resistant outer cartons protect the parts during transport.

Applications for Metallized Alumina Ceramic Substrates

Metallized alumina substrates combine electrical insulation with patterned metal surfaces for current conduction, heat spreading and joining. The appropriate ceramic thickness, metallization route and surface finish should be selected according to the drawing, assembly process and operating requirements.

Power Modules, Inverters & Power Supplies

Engineering need
Electrically isolate semiconductor devices while carrying current and transferring heat toward the baseplate or cooling interface.

How the substrate supports the design
Alumina provides the insulating ceramic base, while the copper or metallized pattern provides conductive, attachment and heat-spreading surfaces.
LED, Laser-Diode & Electronic Packages

Engineering need
Combine an electrically insulating base with patterned metal features and a surface finish compatible with die attach, soldering or wire bonding.

How the substrate supports the design
The alumina ceramic provides electrical isolation and dimensional stability, while the metallization defines the circuit and assembly interfaces.
Thermoelectric & Peltier Modules

Engineering need
Provide insulated connection surfaces and a controlled interface for module assembly and operation.

How the substrate supports the design
Patterned metallization creates the required electrical connection areas, while alumina provides ceramic support and electrical separation.
Brazed & Hermetic Ceramic-to-Metal Assemblies

Engineering need
Create a controlled, finish-ready metallized interface for brazing or another specified ceramic-to-metal joining process.

How the substrate supports the design
Mo-Mn or tungsten thick-film metallization with a reviewed plating system can provide a joining surface matched to the assembly design.

Metalized Alumina Substrate Usage Instructions

Receiving and Storage

1. Inspection: Check the protective packaging and substrates for damage, contamination, edge chips, or coating defects upon receipt.
2. Storage: Keep substrates in their original clean packaging in a dry, controlled environment.
3. Contamination Control: Keep them away from dust, moisture, sulfur compounds, and corrosive chemicals that may affect the metal finish.
4. Storage Period: Follow the confirmed storage limits for the specified surface finish and assembly process.
Handling and Preparation

1. Handling: Hold substrates by the edges using powder-free gloves or finger cots.
2. Mechanical Protection: Do not bend, drop, or place heavy objects on the substrates. Use suitable padded trays during handling and transport.
3. Cleaning: Use only a cleaning or bake-out process approved for the selected metallization, surface finish, and assembly method.
Assembly and Soldering

1. Material Application: Use solder paste, braze material, or bonding materials compatible with the specified surface finish and assembly design.
2. Component Placement: Control placement force to prevent ceramic cracking, edge damage, or metallization damage.
3. Thermal Profile: Establish and validate the preheating, joining, and cooling profile according to the assembly materials, substrate stack-up, and equipment.
Post-Assembly Cleaning and Inspection

1. Cleaning: Follow the flux or bonding-material supplier’s recommended cleaning process. Avoid aggressive ultrasonic cleaning unless it has been validated for the assembly.

2. Inspection: Check the joints, component alignment, metallized surfaces, edges, and corners according to the approved drawing and quality plan.

Metalized Alumina Substrate FAQ

Q: Is the alumina dielectric-strength value enough to confirm the working voltage?
A: No. Dielectric strength describes the ceramic material under specified test conditions, not the voltage rating of the finished module. Ceramic thickness, conductor spacing, pattern geometry, surface condition, operating environment and test method must also be reviewed.
Q: How is the maximum operating temperature determined?
A: There is no single temperature rating for every metallized alumina substrate. The practical limit depends on the ceramic, metallization route, surface finish, joining system, attached components, exposure time and thermal-cycle conditions.
Q: What can cause the metal layer to separate from the ceramic?
A: Possible causes include surface contamination, unsuitable metallization, excessive thermal or mechanical stress, poorly designed metal geometry and an assembly process that does not match the substrate stack-up. Project-specific process validation is required.
Q: How should thermal-cycling requirements be specified?
A: Please define the minimum and maximum temperatures, ramp rate, dwell time, required cycle count, mounting condition, cooling interface and acceptance criteria. Power cycling and environmental cycling should be identified separately.
Q: How should the surface finish be selected?
A: The finish must match the downstream joining process. Bare copper, nickel, nickel/gold or silver may be considered depending on whether the substrate will be soldered, brazed or wire-bonded.
Q: Can partial or patterned metallization be requested?
A: Yes. Partial or patterned metallization can be evaluated from a drawing showing the coated areas, keep-out zones, pattern dimensions, alignment requirements, metal thickness and surface finish. Final manufacturability is confirmed during drawing review.
Q: Can ADCERAX evaluate an existing substrate as a second-source option?
A: Yes. ADCERAX can review the existing drawing, ceramic grade, layer stack-up, metallization route, finish and qualification requirements. The proposed alternative must be evaluated and validated before production approval.
Q: Are ceramic-body properties the same as finished-substrate properties?
A: No. Density, dielectric strength, thermal expansion and thermal conductivity describe the ceramic body. Metal thickness, adhesion, pattern accuracy and surface finish describe the metallization system. Finished performance also depends on the interfaces, geometry and assembly conditions.
Q: How are tolerances and acceptance criteria confirmed?
A: Critical dimensions, pattern registration, flatness, edge condition, metal thickness, surface finish and required tests should be defined in the approved drawing or quality document before production.
Q: What should be controlled when moving from prototypes to repeat production?
A: The approved drawing revision, ceramic grade, metallization process, layer thicknesses, surface finish, critical dimensions, inspection criteria and packaging requirements should be fixed before repeat production. Any material, process or design change should be reviewed before implementation.

Catalog No.	AT-DBC-C001
Material	≥ 96% Al2O3
Dielectric Strength	≥20 kV/mm
Flatness Tolerance	±0.1 mm
Dimensions/Sizes	Download PDF

Alumina Metalized Ceramic Substrate for Power Electronics and RF Applications

Alumina Metalized Ceramic Substrate Benefits

Metalized Alumina Substrate Properties

Al₂O₃ Metalized Ceramic Substrate Specifications

Metalized Alumina Substrate Packaging

Applications for Metallized Alumina Ceramic Substrates

Power Modules, Inverters & Power Supplies

LED, Laser-Diode & Electronic Packages

Thermoelectric & Peltier Modules

Brazed & Hermetic Ceramic-to-Metal Assemblies

Metalized Alumina Substrate Usage Instructions

Receiving and Storage

Handling and Preparation

Assembly and Soldering

Post-Assembly Cleaning and Inspection

Metalized Alumina Substrate FAQ

Customize Alumina Metalized Substrates

Related Products

Metalized Aluminum Nitride Substrate for LED and IGBT Modules – Custom Sizes Available

AMB Silicon Nitride (Si₃N₄) Substrate for Automotive Traction Inverters and DC/DC Converters

High Purity Alumina Ceramic Substrates for RF, LED and Sensor Assemblies

Bare Aluminum Nitride Substrates for Power, LED and RF Modules

ADCERAX - Your Trusted Advanced Ceramics Manufacturing Partner

Get in Touch with Us

Ready to Solve Your Engineering Challenge?

Alumina Metalized Ceramic Substrate for Power Electronics and RF Applications

Alumina Metalized Ceramic Substrate Benefits

Metalized Alumina Substrate Properties

Al₂O₃ Metalized Ceramic Substrate Specifications

Metalized Alumina Substrate Packaging

Applications for Metallized Alumina Ceramic Substrates

Power Modules, Inverters & Power Supplies

LED, Laser-Diode & Electronic Packages

Thermoelectric & Peltier Modules

Brazed & Hermetic Ceramic-to-Metal Assemblies

Metalized Alumina Substrate Usage Instructions

Receiving and Storage

Handling and Preparation

Assembly and Soldering

Post-Assembly Cleaning and Inspection

Metalized Alumina Substrate FAQ

Customize Alumina Metalized Substrates

Related Products

Metalized Aluminum Nitride Substrate for LED and IGBT Modules – Custom Sizes Available

AMB Silicon Nitride (Si₃N₄) Substrate for Automotive Traction Inverters and DC/DC Converters

High Purity Alumina Ceramic Substrates for RF, LED and Sensor Assemblies

Bare Aluminum Nitride Substrates for Power, LED and RF Modules

ADCERAX - Your Trusted Advanced Ceramics Manufacturing Partner

Get in Touch with Us

Ready to Solve Your Engineering Challenge?

Quick Quote

Get Your Custom Solution

Download Catalog