PAM-XIAMEN’ product line includes single-sided polishing (SSP) and double-sided polishing (DSP) wafer substrate or called mirror polished wafer for applications of semiconductors, MEMS, and other chips that require a strictly controlled flatness often require double-sided polishing chips. They are also necessary for a two-sided pattern and device manufacturing project. Normally end users will buy double side polished wafers due to better flatness. The roughness surface of polishing wafer should be required to Ra<0.5nm or 0.2nm.

Although semiconductor devices continue to shrink, it is increasingly important for chips to have high surface quality on both the front and back sides. At present, these chips are most commonly used in microelectro mechanical systems (MEMS) and applications with strict flatness requirements. PAM-XIAMEN offers a large number of double-sided polished wafers, all with diameters ranging from 50mm to 150mm. If we do not have your specifications in our inventory, we have established long-term relationships with a number of suppliers who are able to customize the wafers to suit any particular specifications.

1. Polishing Wafer List of Silicon Carbide

4″ 4H Silicon Carbide
Item No.	Type	Orientation	Thickness	Grade	Micropipe Density	Surface	Usable area
	N-Type
S4H-100-N-SIC-350-A	4″ 4H-N	0°/4°±0.5°	350±25um	A	<10/cm2	P/P	>90%
S4H-100-N-SIC-350-B	4″ 4H-N	0°/4°±0.5°	350±25um	B	< 30/cm2	P/P	>85%
S4H-100-N-SIC-350-D	4″ 4H-N	0°/4°±0.5°	350±25um	D	<100/cm2	P/P	>75%
S4H-100-N-SIC-370-L	4″ 4H-N	0°/4°±0.5°	370±25um	D	*	L/L	>75%
S4H-100-N-SIC-440-AC	4″ 4H-N	0°/4°±0.5°	440±25um	D	*	As-cut	>75%
S4H-100-N-SIC-C0510-AC-D	4″ 4H-N	0°/4°±0.5°	5~10mm	D	<100/cm2	As-cut	*
S4H-100-N-SIC-C1015-AC-C	4″ 4H-N	0°/4°±0.5°	5~10mm	C	<50/cm2	As-cut	*

3″ 4H Silicon Carbide
Item No.	Type	Orientation	Thickness	Grade	Micropipe Density	Surface	Usable area
	N-Type
S4H-76-N-SIC-350-A	3″ 4H-N	0°/4°±0.5°	350±25um	A	<10/cm2	P/P	>90%
S4H-76-N-SIC-350-B	3″ 4H-N	0°/4°±0.5°	350±25um	B	< 30/cm2	P/P	>85%
S4H-76-N-SIC-350-D	3″ 4H-N	0°/4°±0.5°	350±25um	D	<100/cm2	P/P	>75%
S4H-76-N-SIC-370-L	3″ 4H-N	0°/4°±0.5°	370±25um	D	*	L/L	>75%
S4H-76-N-SIC-410-AC	3″ 4H-N	0°/4°±0.5°	410±25um	D	*	As-cut	>75%
S4H-76-N-SIC-C0510-AC-D	3″ 4H-N	0°/4°±0.5°	5~10mm	D	<100/cm2	As-cut	*
S4H-76-N-SIC-C1015-AC-D	3″ 4H-N	0°/4°±0.5°	10~15mm	D	<100/cm2	As-cut	*
S4H-76-N-SIC-C0510-AC-C	3″ 4H-N	0°/4°±0.5°	5~10mm	C	<50/cm2	As-cut	*
S4H-76-N-SIC-C1015-AC-C	3″ 4H-N	0°/4°±0.5°	10~15mm	C	<50/cm2	As-cut	*

SEMI-INSULATING

S4H-76-SI-SIC-350-A	3″ 4H-SI	0°/4°±0.5°	350±25um	A	<10/cm2	P/P	>90%
S4H-76-SI-SIC-350-B	3″ 4H-SI	0°/4°±0.5°	350±25um	B	< 30/cm2	P/P	>85%
S4H-76-SI-SIC-350-D	3″ 4H-SI	0°/4°±0.5°	350±25um	D	<100/cm2	P/P	>75%

2″ 4H Silicon Carbide
Item No.	Type	Orientation	Thickness	Grade	Micropipe Density	Surface	Usable area
	N-Type
S4H-51-N-SIC-330-A	2″ 4H-N	0°/4°±0.5°	330±25um	A	<10/cm2	C/P	>90%
S4H-51-N-SIC-330-B	2″ 4H-N	0°/4°±0.5°	330±25um	B	< 30/cm2	C/P	>85%
S4H-51-N-SIC-330-D	2″ 4H-N	0°/4°±0.5°	330±25um	D	<100/cm2	C/P	>75%
S4H-51-N-SIC-370-L	2″ 4H-N	0°/4°±0.5°	370±25um	D	*	L/L	>75%
S4H-51-N-SIC-410-AC	2″ 4H-N	0°/4°±0.5°	410±25um	D	*	As-cut	>75%
S4H-51-N-SIC-C0510-AC-D	2″ 4H-N	0°/4°±0.5°	5~10mm	D	<100/cm2	As-cut	*
S4H-51-N-SIC-C1015-AC-D	2″ 4H-N	0°/4°±0.5°	10~15mm	D	<100/cm2	As-cut	*
S4H-51-N-SIC-C0510-AC-C	2″ 4H-N	0°/4°±0.5°	5~10mm	C	<50/cm2	As-cut	*
S4H-51-N-SIC-C1015-AC-C	2″ 4H-N	0°/4°±0.5°	10~15mm	C	<50/cm2	As-cut	*

2″ 6H Silicon Carbide
Item No.	Type	Orientation	Thickness	Grade	Micropipe Density	Surface	Usable area
	N-Type
S6H-51-N-SIC-330-A	2″ 6H-N	0°/4°±0.5°	330±25um	A	<10/cm2	C/P	>90%
S6H-51-N-SIC-330-B	2″ 6H-N	0°/4°±0.5°	330±25um	B	< 30/cm2	C/P	>85%
S6H-51-N-SIC-330-D	2″ 6H-N	0°/4°±0.5°	330±25um	D	<100/cm2	C/P	>75%
S6H-51-N-SIC-370-L	2″ 6H-N	0°/4°±0.5°	370±25um	D	*	L/L	>75%
S6H-51-N-SIC-410-AC	2″ 6H-N	0°/4°±0.5°	410±25um	D	*	As-cut	>75%
S6H-51-N-SIC-C0510-AC-D	2″ 6H-N	0°/4°±0.5°	5~10mm	D	<100/cm2	As-cut	*
S6H-51-N-SIC-C1015-AC-D	2″ 6H-N	0°/4°±0.5°	10~15mm	D	<100/cm2	As-cut	*
S6H-51-N-SIC-C0510-AC-C	2″ 6H-N	0°/4°±0.5°	5~10mm	C	<50/cm2	As-cut	*
S6H-51-N-SIC-C1015-AC-C	2″ 6H-N	0°/4°±0.5°	10~15mm	C	<50/cm2	As-cut	*

 

2. Criteria for Producing Polished Monocrystalline Silicon Carbide Wafer

This standard applies to 4H and 6H silicon carbide single crystal polishing wafers prepared after single-sided or double-sided polishing. The polishing wafer is mainly used to make epitaxial substrates for semiconductor lighting and power electronic devices.

2.1 Technical Parameters

The technical parameters of silicon carbide single crystal polishing wafer refer to the requirements in the fixed high-quality area, and the edge removal area should meet the requirements of Table 1.

Table 1 Edge Removal Area

Diameter	Edge Removal Area
50.8mm	1mm
76.2mm	2mm
100mm	3mm

 

2.2 Classification of Polished SiC Wafer

Silicon carbide single crystal polishing wafers are divided into 4H and 6H according to the crystal types.

Silicon carbide single crystal polishing substrates are divided into conductive type and semi-insulating type according to their conductivity.

2.3 Polished Silicon Carbide Wafer Specifications

Diameter: silicon carbide polishing wafers are divided into 50.8mm, 76.2mm and 100mm in diameter.

Product Quality: silicon carbide single crystal polished wafers are divided into industrial grade (referred to as P grade), research grade (referred to as R grade) and test grade (referred to as D grade).

2.4 SiC Polishing Wafer Geometric Parameters

The geometric parameters of polished silicon carbide wafer should meet the requirements of Table 2.

Table 2 Geometry Parameters of Polishing Wafer

No.	Item	Requirement
		50.8 mm	76.2 mm	100.0 mm
1	Diameter and allowable deviation/ mm	50.8±0.2	76.2±0.2	100.0±0.5
2	Length of main positioning edge and allowable deviation/mm	16.0±1.7	22.0±2.0	32.5±2.0
3	Length of secondary positioning edge and allowable deviation/mm	8.0±1.7	11.0±1.5	18.0±2.0
4	Main positioning edge orientation	Parallel to {10 10} ± 5°	Parallel to {10 10} ± 5°	Parallel to {10 10} ± 5°
5	Secondary positioning edge orientation	Silicon surface: rotate 90°±5° clockwise along the main positioning edge; Carbon surface: rotate 90°±5° counterclockwise along the main positioning edge	Silicon surface: rotate 90°±5° clockwise along the main positioning edge; Carbon surface: rotate 90°±5° counterclockwise along the main positioning edge	Silicon surface: rotate 90°±5° clockwise along the main positioning edge; Carbon surface: rotate 90°±5° counterclockwise along the main positioning edge
6	Thickness and allowable deviation/um	330±25	350±25	350±25
7	Total thickness variation/um	≤15	≤15	≤25
8	Warpage/um	≤25	≤35	≤45
9	Curvature (absolute value)/um	≤15	≤25	≤35
10	Roughness (10 um× 10 um)/nm	<0.5	<0.5	<0.5
Note: When the customer has special requirements for thickness, it shall be negotiated and determined by both parties.

 

2.5 Polishing Wafer Surface Orientation

The crystal orientation of the monocrystalline polished silicon carbide wafer is {0001}.

The orthorhombic crystal orientation deviation of the SiC polished wafer surface orientation is:

a) Normal crystal orientation: 0°±0.25°;

b) Monochrome orientation: The deviation of the orthorhombic orientation of the polished wafer of silicon carbide is the deviation of the normal line of the wafer surface along the main positioning edge direction (11 20) direction 3.5°±0.5° or 4°±0.5° or 8°±0.5 °.

2.6 Surface Defects of Polished Silicon Carbide Wafers

The surface defects of silicon carbide single crystal polished wafers should meet the requirements of Table 3:

Table 3: SiC Single Crystal Polishing Wafer Surface Defects

Item	Industrial Grade			Research Grade			Test Grade
	50.8mm	76.2mm	100mm	50.8mm	76.2mm	100mm	50.8mm	76.2mm	100mm
Crack	Located at the edge of the chip and			Located at the edge of the chip and			Cumulative length ≤ 10 mm, and each length ≤ 2 mm
	<1mm	<2mm	<3mm	<2mm	<3mm	<3mm
Hexagonal Cavity	Size <100um, and the number			Size <300um, and the number			No separate requirement, meet usable area>70%
	≤2	≤4	≤6	≤5	≤8	≤12
Scratches	None			None			Cumulative length <1 diameter, and
							≤3	≤5	≤8
Surface Contamination	None			None			None
Pit	≤5	≤12	≤20	≤20	≤45	≤80	No separate requirement, meet usable area>70%

 

The microtube density of single crystal SiC polished wafers should meet the requirements of industrial grade <10 pcs/cm², research grade <30 pcs/cm², and test grade <100 pcs/cm².

2.7 Silicon Carbide Polishing Wafer Crystal Quality

The crystal quality of silicon carbide single crystal polishing wafers is expressed by the full width at half maximum (FWHM) of the rocking curve. The FWHM of 4H-SiC (0004) or 6H-SiC (0006) should meet the requirements of industrial grade less than 30arcsec, research grade less than 50arcsec, and test grade no level required.

2.8 Silicon Carbide Polished Substrate Resistivity

The resistivity of the silicon carbide single crystal polished sheet should meet the requirements of Table 4:

Table 4 SiC Polished Substrate Resistivity

Conductivity Type	Crystal Form	Industrial Grade	Research Grade	Test Grade
Conductive	4H	<0.025	<0.1	<0.1
	6H	<0.1	<0.2	<0.2
Semi-insulating	4H/6H	(90%) >1 *105	(85%) >1*105	(75%) >1*105

 

2.9 Testing Method for SiC Polishing Film

Surface orientation: The surface orientation of the silicon carbide polished thin film should be measured according to the regulations, and the crystal reference plane is oriented with an X-ray orientation instrument;

Microtubule density: The polishing wafer microtube density should be observed with an optical microscope under transmission cross-polarized light according to the prescribed method;

Crystal quality: The quality of the junction quality of the polished SiC substrate wafer is tested by high-resolution X-ray radiation according to the prescribed method, only by the double crystal rocking curve.

For more information, please contact us email at victorchan@powerwaywafer.com and powerwaymaterial@gmail.com.