semi合集-English.pdf - 第5379页

SEMI M55.1-0304 © SEMI 2004 2 Table 3 Orientat ion and Flat Loca tion Requirements Property Dimension SURFACE ORIENTATION (see Note 1) Tilt angle (see Figure 2 in SEMI M55) Option 1: “on axis” 0 + 0.25° Option 2: “off ax…

100%1 / 7923
SEMI M55.1-0304 © SEMI 2004 1
SEMI M55.1-0304
SPECIFICATION FOR 50.8 mm ROUND POLISHED
MONOCRYSTALLINE 4H AND 6H SILICON CARBIDE WAFERS
This specification was technically approved by the Global Compound Semiconductor Committee and is the
direct responsibility of the European Compound Semiconductor Materials Committee. Current edition
approved by the European Regional Standards Committee on October 29, 2003. Initially available at
www.semi.org January 2004; to be published March 2004.
NOTE 1: This specification is intended to be a sub-document to SEMI M55, Specification For Polished Monocrystalline Silicon
Carbide Wafers.
1 Purpose
1.1 This subordinate standard details the dimensional values and other information required for 50.8 mm polished
monocrystalline silicon carbide wafers.
2 Scope
2.1 The complete specification for this product includes all general requirements of SEMI M55, Specification For
Polished Monocrystalline Silicon Carbide Wafers.
NOTICE: This standard does not purport to address safety issues, if any, associated with its use. It is the
responsibility of the users of this standard to establish appropriate safety and health practices and determine the
applicability of regulatory or other limitations prior to use.
3 Limitations
3.1 The backside finish properties, dopant, and resistivity are not addressed, as currently these properties depend
strongly on the quick evolving technology and suitable limits for a standard do not exist.
4 Requirements
Table 1 Dimension and Tolerance Requirements
Property Dimension Tolerance Units
DIAMETER 50.8
± 0.25
mm
PRIMARY FLAT LENGTH 15.8
± 1.6
mm
SECONDARY FLAT LENGTH 8.0
± 1.6
mm
BOW 0
± 25
µ m
WARP 0 < 25 µ m
TOTAL THICKNESS VARIATION 0 < 25 µ m
TOTAL INDICATOR READING 0 < 25 µ m
Table 2 Thickness Requirements (Center Point)
Dimension Tolerance Units
Option 1: 250
± 25
µ m
Option 2: 330
± 25
µ m
NOTE 1: As the industrial requirements for a unique thickness specification are not established at the time of creation of this standard, two
values are defined. This is to be regarded as a preliminary in that way, that in a future revision of this standard these options can be expected to
be replaced by a unique definition.
SEMI M55.1-0304 © SEMI 2004 2
Table 3 Orientation and Flat Location Requirements
Property Dimension
SURFACE ORIENTATION
(see Note 1)
Tilt angle (see Figure 2 in SEMI M55)
Option 1: “on axis”
0 + 0.25°
Option 2: “off axis (1120)”
3.5° ± 0.5° parallel to edge of primary flat away from secondary flat
(see Note 1)
Option 3: “off axis (1120)”
8.0° ± 0.5° parallel to edge of primary flat away from secondary flat
(see Note 1)
Option 4: “off axis (1100)”
3.5° ± 0.5° parallel to edge of secondary flat away from primary flat
(see Note 1)
Option 5: “off axis (1100)”
8.0° ± 0.5° parallel to edge of secondary flat away from primary flat
(see Note 1)
ORTHOGONAL MISORIENTATION
± 5° (See Figure 2 in SEMI M55)
TOLERANCE OF PRIMARY FLAT
ORIENTATION
± 1°
TOLERANCE OF SECONDARY FLAT
ORIENTATION (see Note 4)
± 5° relative to primary flat
NOTE 1: The frame of reference is the (0001)-plane of the crystal. It is the wafer normal on the silicon-face that is tilted towards the given
crystallographic direction. That means that the crystallographic c-axis lies between the secondary/primary flat (for the (1120)/(1100) option) and
the silicon-face surface normal vector (See Figure 1 and 2).
NOTE 2: The angle between primary and secondary flat is defined in Figure 5 in SEMI M55.
Secondary flat
Si-face
Normal vector to
wafer surface
Crystallographic
c-axis
C-face
Primary flat
Si-face
Normal vector to
wafer surface
Crystallographic
c-axis
C-face
Figure 1
Definition of the Sign of the Tilt Angle (left: off axis (1120) -option, right off axis (1100) Option)
SEMI M55.1-0304 © SEMI 2004 3
tilt angle tilt angle
off towards [1120]
direction
off towards [1100 ]
dir ec tion
[1120]
dire cti on
[1120]
directi on
(1100) plane
(1100) p lan e
Figure 2
Direction of Tilt (left: (1120) option, right off axis (1100) option)
Table 4 Polished Wafer Defect Limits
Item Characteristics Maximum Defect Limit Test Condition Note
Front Surface
1 visible scratches none high intensity, unaided eye 1
2 pits (number) 10 high intensity, unaided eye 1
3 orange peel (area) 10 % diffuse, unaided eye 1
4 particles (number) 4 high intensity, unaided eye 1
5 edge chips and indents (number)
≤ 3 with maximum length and
width 1.0 mm
Back Surface
6 edge chips (number)
≤ 3 with maximum length and
width 1.0 mm
Bulk
7 cracks (number) none diffuse, unaided eye
8 micropipes (mean density) defined by customer and supplier
9 planar defects,
spacing >2 mm (number)
10 diffuse, unaided eye 1
10 planar defects,
spacing ≤ 2 mm (affected area)
10 % diffuse, unaided eye 1
11 crystallite (area) 5 % diffuse, polarisers 1
12 foreign polytypes (area) 10 % diffuse 1
Cumulative Defect Area
12 all listed defects of type “area” total 10 % 1
NOTE 1: The Edge-Exclusion X (See Figure 1 of SEMI M55) is 1 mm.