Design guidelines

Scribed substrates

Laser Tech. will provide scribed substrates to the customers desired application
General tolerances for economic manufacture are:

Advanced scribing possibilities

Laser Tech’s unique laser technology makes previous impossible scribing pattern possible

Laser drilling and profiling

Laser Tech will provide the combined laserdrilled, -profiled and -scribed substrates to the customers desired specification. General tolerances for optimized economic manufacture are:

General design rules for optimized economic manufacture are:

With request of improved tolerances and designs in conflict with the general design rules please contact Laser Tech.’s technical sales department for possible available improvements.

PrimEdge™ and Super PrimEdge™

The rational answer to improved thickfilm yield and the most economical solution to quality edge finish.

Advantages and benefits:

• Surface and bottom edge equally treated, for identical use of A and B
• Dimensional tolerances better than on standard scribed
• No edge chipping by substrate handling.
• Reduced laser edge stresses (edge microcraks).
• No torn printing screens due to rough and sharp
• Reduced location pin wear (better printing repeatability).

All benefits are leading to a higher production yield, to a cost only slightly higher than for a standard scribed substrate.

Super PrimEdge™

The ultimate answer to quality edge finish and superior printing repeatability for “state of the art” fineline printing and printed through hole technology

Advantages and benefits:

• Surface and bottom edge treated, for identical use of A and B
• Rounded corners (radius 1 mm) for troublefree cassette handling and to avoid the well known sharp corner chipping.
• Laser profiled alignment slots for optimal print repeatability, with tolerances superior to any other edge treatment

All benefits are resulting in significantly higher production yield of advanced thickfilm substrates.

CeramTec material properties

Properties	Units	Rubalit® 708S 96% Al₂O₃	Rubalit® 710 99,6% Al₂O₃	Alunit® Ain	Test per
Colour	–	white	white	translucent medium gray	–
Medium grain size d₅₀	µm	3-5	2	4-5	–
Surface roughness Rₐ	µm	0.6 max	0.1	0.6 max	–
Bulk density	kg/m³	3780	3900	3330	ASTM C 20
Water absorption capacity	%	0	0	0	ASTM C 373
Bending strength – 4-point method (40×4×3 mm³) – dual-ring method (0.63 mm substrate thickness)	Mpa MPa	400 500	400	360	ASTM F 417 DIN 52292
Modulus of elasticity	GPa	340	350	320	ASTM F 417
Thermal conductivity 20-100° C	W/m° K	24	28	180	ASTM C 408
Specific heat	J/kg° K	800	–	738
Coefficient of
linear expansion	10⁻⁶/° K				ASTM C 373
20-300° C		6.8	6.8	4.7
20-600° C		7.3	7.5	5.2
20-1000° C		8.0	8.5	5.6
Dielectric constant – 1 MHz – 1 GHz		9.8 ± 10% 10.0 ± 10%	10.1 ± 10% 10.1 ± 10%	9.0 ± 10%	ASTM C 150
Dielectric loss factor (1 MHz)	10⁻³	0.3	0.2	0.4	ASTM D 150
Breakdown Strength	KV/mm				ASTM D 149
– 1 mm substrate
thickness		15		16
– 0.63 mm substrate
thickness		20	> 10
– 0.25 mm substrate
thickness		28
Volume resistivity – 20° C	Ohm x cm	10¹³ 10¹² 10¹¹ 10⁸	10¹³ 10¹³ 10¹² 10⁹	10¹³	ASTM D 257
– 200° C
– 400° C
– 600° C

CoorsTek

Characteristic	Unit	Test Method	ADOS-90R	ADS-96R
Alumina Content	Weight %	ASTM D 2442	91	96
Colour	–	–	Dark Brown	White
Density	g/cm³	ASTM C 373	3.72 min.	3.75 min.
Hardness – Rockwell	–	ASTM E18, R45N	78	82
Surface Finish – CLA (as fired)	Microinches	Profilometer .0004" Radius Stylus .030" Cut-off ANSI/ASME B 46.1	≤ 45	≤ 35
Average Grain Size	Micrometers	Intercept Method	5-7	4-7
Water Absorption	%	ASTM C 373	NIL	NIL
Gas Permeability	–	*	NIL	NIL
Flexural Strength	Kpsi	ASTM F 394	53	58
Elastic Modules	10⁶ psi	ASTM C 623	45	44
Poisson's Ratio	–	ASTM C 623	.24	.21
Coefficient of Linear Thermal Expansion 25° -200° C 25° -500° C 25° -800° C 25° -1000° C	10⁻⁶/° C	ASTM C 372	6.4 7.3 8.0 8.4	6.3 7.1 7.6 8.0
Thermal Conductivity 20° C 100° C 400° C	W/m° K	Various	13 12 8	26 20 12
Dielectric Strength (60 cycles AC avg. RMS) .025" thick .050" thick	Volts/mil	ASTM D 149	540 –	600 –
Dielectric Constant (Relative Permittivity) 1 KHz 1 MHz	–	ASTM D 150	11.8 10.3	9.5 9.5
Dissipation Factor (Loss Tangent) 1 KHz 1 MHz	–	ASTM D 150	.1 .005	.0010 .0004
Loss Index (Loss Factor) 1 KHz 1 MHz	–	ASTM D 150	1.2 .05	.009 .004
Volume Resistivity 25° C 300° C 500° C 700° C	ohm-cm	ASTM D 1829	> 10¹⁴ 4 × 10⁸ – 7 × 10⁶	> 10¹⁴ 5.0 × 10¹⁰ 1.0 × 10⁹ 4.0 × 10⁷

* Helium leak through a plate 1" diameter by 0.010" thick measured at 3 × 10-7 torr vacuum versus approximately one atmosphere of helium pressure for 15 seconds at room temperature.

Kyocera material properties

Item				Material
				ALUMINA (AI₂O₃)
Kyocera No.				A-445	A-459	A-473	A-476	A-493
Appearance				Dense	Dense	Dense	Dense	Dense
Colour				Dark Brown	Russet	White	White	White
Alumina Content (%)				91	90	92	96	99.6
Main Characteristics				Opacity High Heat Dissipation	High temperature and themal shock resistance	Metallizing Mechanically Strong	Standard Substrate Material	Good surface Smoothness
Main Applications				IC Packages Lids	Metallization	Lids, Substrates For Refractory	Thick Film Substrates	Thick Film Substrates
Bulk Density			–	3.9	3.6	3.6	3.8	3.9
Water Absorption			%	0	0	0	0	0
Mechanical Characteristics	Vickers Hardness (Load 500 g)		kg/mm²	1.100	1.300	1.350	1.500	1.650
	Flexural Strength		psi kg/cm²	30,000 2,100	41,000 2,900	46,000 3,200	40,000 2,800	70,000 5,000
	Compressive Strength		psi kg/cm²	–	–	–	–	–
	Young's (x10⁶) Modulus (x10⁶)		psi kg/cm²	–	37 2.6	39 2.7	–	–
Thermal Characteristics	Coefficient of Linear Thermal Expansion	40°~ 400°C	1/°C (x10⁻⁶)	7.2	7.0	6.9	7.1	7.2
		40°~ 800°C		8.1	7.8	7.7	7.8	8.2
	Thermal Conductivity	20°C	cal · cm cm² · sec · °C	0.04	0.04	0.04	0.05	0.08
	Specific Heat		cal/g°C	0.19	0.20	0.19	0.19	0.19
	Max. Use Temperature		°C	1,200	1,500	1,500	1,600	1,750
Electrical Characteristics	Dielectric Strength		kv/mm	10	10	10	10	10
	Volume Resistivity	20°C 300°C 500°C	Ω · cm	> 10¹²	10¹⁴	> 10¹⁴	> 10¹⁴	> 10¹⁴
				10⁸	10¹²	10¹³	10¹⁴	10¹⁴
				10⁷	109	10¹⁰	10¹¹	10¹²
	Dielectric (1 MHz) Constant		–	7.9	8.5	9.5	10.2	9.9
	Dielectric (1 MHz) Loss Angle		(10⁻⁴)	–	3	8	2	2
	Loss Factor		(x10⁻⁴)	–	25	76	19	19

Specifications for surface imperfections

Visual Inspection, based on a sample inspection according to ISO 2859 level II Cum. AQL 2.5 %

1. Crack	None
2. Chips	≤ 0,5 mm width (t) Depth max. 50 % of substrate thickness
3. Surface Scratches	None more than .0007" (0,018 mm) in depth
4. Lumps	None more than ≤ 0,025 mm high
5. Burr	None more than .0008" (0,02 mm) high
6. Ridge	None more than .001" (0,025 mm) high
7. Pin Holes	None more than .007" (0,18 mm) "diameter
8. Porous Area	None opened to the surface
9. Waveness	Acceptable if within specified camber
10. Foreign Material	Acceptable unless exposed even if it shows discoloration