4 in Silicon Carbide Wafers 4H-SiC N-Type or Semi-Insulating SiC Substrates

Grade

Production Grade

Research Grade

Dummy Grade

Diameter

100.0 mm +/- 0.5 mm

Thickness

500 um +/- 25 um (semi-insulating type), 350 um +/- 25 um (N type)

Wafer Orientation

On axis: <0001> +/- 0.5 deg for 4H-SI

Off axis: 4.0 deg toward <11-20> +/-0.5 deg for 4H-N

Micropipe Density (MPD)

5 cm^-2

15 cm^-2

30 cm^-2

Electrical Resistivity

(Ohm-cm)

4H-N

0.015~0.028

Doping Concentration

N-type: ~ 1E18/cm3

SI-type (V-doped): ~ 5E18/cm3

Primary Flat Length

32.5 mm +/- 2.0 mm

Secondary Flat Length

18.0 mm +/- 2.0 mm

Secondary Flat Orientation

Silicon face up: 90 deg CW from Primary flat +/- 5.0 deg

Edge exclusion

3 mm

LTV/TTV /Bow /Warp

10um /15um /25um /40um 

Surface Roughness

Optical Polish Ra < 1 nm on the C face

CMP Ra < 0.5 nm on the Si face

Cracks inspected by high intensity light

None

1 allowed, 1 mm

1 allowed, 2 mm

Hex Plates inspected by high intensity light*

Cumulative area 1 %

Cumulative area 1 %

Cumulative area 3 %

Polytype Areas inspected by high intensity light*

None

Cumulative area 2%

Cumulative area 5%

Scratches inspected by high intensity light**

3 scratches to 1 x wafer diameter Cumulative length

5 scratches to 1 x wafer diameter Cumulative length

5 scratches to 1 x wafer diameter Cumulative length

Edge chipping

None

3 allowed, 0.5 mm each

5 allowed, 1 mm each

Surface Contamination as inspected by high intensity light

None

Property

4H-SiC Single Crystal

6H-SiC Single Crystal

Lattice Parameters (Å)

a=3.076

c=10.053

a=3.073

c=15.117

Stacking Sequence

ABCB

ABCACB

Density

3.21

3.21

Mohs Hardness

~9.2

~9.2

Thermal Expansion Coefficient (CTE) (/K)

4-5 x 10^-6

4-5 x10^-6

Refraction Index @750nm

no = 2.61

ne = 2.66

no = 2.60

ne = 2.65

Dielectric Constant

c ~ 9.66

c ~ 9.66

Doping Type

N-type or Semi-insulating

N-type or Semi-insulating

Thermal Conductivity (W/cm-K @298K)

(N-type, 0.02 ohm-cm)

a~4.2

c~3.7

Thermal Conductivity (W/cm-K @298K)

(Semi-insulating type)

a~4.9

c~3.9

a~4.6

c~3.2

Band-gap (eV)

3.23

3.02

Break-Down Electrical Field (V/cm)

3-5 x 10⁶

3-5 x 10⁶

Saturation Drift Velocity (m/s)

2.0 x 10⁵

2.0 x 10⁵

Wafer and Substrate Sizes

Wafers: 2, 4, 6, 8 inch; smaller substrates: 10x10, 20x20 mm, other sizes are available and can be custom-made upon request

Product Grades

A Grade Zero micropipe density (MPD 1 cm^-2)

B Grade Production grade (MPD 5 cm^-2)

C Grade Research grade (MPD 15 cm^-2)

D Grade ummy grade (MPD 30 cm^-2)