Alumina | Al₂O₃

Alumina substrates are produced under severe quality control with carefully selected high-purity alumina materials that ensures stable quality and excellent characteristics.

Material Characteristics for Alumina Substrates (Al₂O₃), Zirconia Toughened Alumina Substrates ( Al₂O₃/ZrO₂), Aluminium Nitride Substrates (AlN), and Silicon Nitride (Si₃N₄)

		Condition	Unit	Al₂O₃					Al₂O₃/ZrO₂		AlN	Si₃N₄
		Condition	Unit	AS970	HA-96-2	HBS	HRA	HA-996	ZTA	HRZ	AN-170	SN-90
Material		-	-	96.5%	96%	96.5%	96%	99.6%	Al₂O₃/ZrO₂	Al₂O₃/ZrO₂	AlN	Si₃N₄
Color		-	-	White	White	White	White	White	White	White	Gray	Gray
Bulk density		-	g/㎤	3.74	3.75	3.75	3.60	3.90	4.00	3.85	3.30	3.22
Surface roughness Ra		-	µm	0.4	0.4	0.3	0.3	0.1	0.2	0.2	0.2	0.4
Reflectivity		0.3-0.4mmt	%	70	70	70	85	75	80	87	35	-
Reflectivity		0.8-1.0mmt	%	80	80	80	95	85	90	97	25	-
Mechanical	Bending strength	3-point method	MPa	450	400	500	370	470	700	550	450	800
	Modulus of elasticity	-	GPa	330	330	330	-	330	310	-	320	310
	Vickers hardness	-	GPa	14	14	14	-	16	15	14	11	15
	Fracture toughness	IF method	MPa･m^1/2	3.0	3.0	-	-	-	3.5	-	3.0	6.5
Thermal	Coefficient of thermal expansion	40-400°C	10^-6/K	6.7	6.7	6.7	6.7	6.8	7.1	7.1	4.6	2.6
	Coefficient of thermal expansion	40-800°C	10^-6/K	7.8	7.8	7.8	7.8	7.9	8.0	8.0	5.2	3.1
	Thermal conductivity	25°C	W/(m･K)	24	24	24	20	29	27	23	180	85
	Thermal conductivity	300°C	W/(m･K)	12	12	12	-	13	16	-	120	-
	Specific heat	25°C	J/(㎏･K)	750	750	750	750	780	720	720	720	680
Electrical	Dielectric constant	1MHz	-	9.8	9.8	9.8	-	9.9	10.2	-	8.5	7.8
	Dielectric loss factor	1MHz	10^-3	0.2	0.2	0.2	-	0.2	0.2	-	0.3	0.4
	Volume resistivity	25°C	Ω･㎝	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴
	Breakdown strength	DC	㎸/㎜	>15	>15	>15	>15	>15	>15	>15	>15	>15

Characteristic Values

List of Products

Alumina Substrates

LED packages, Power modules, FAX substrates for thermal printer head
*Various processing is available (thin film metalization, thick film metalization, glaze, etc.)