semi合集-English.pdf - 第27页
SEMI E1.9-0701 E2 © SEMI 1994, 2004 7 x 17 =17.5 x 14 =118.5 y 19 =61.1 y 17 =27.5 x 13 =88.5 front side of the cassette where waf ers are accessed carr ier sen sing pads facial datum plane bilateral datum plane y 10 =12…
SEMI E1.9-0701
E2
© SEMI 1994, 2004 6
6.5 Cassette Bottom — Figure 4 shows a bottom view
of the horizontal boundaries of the cassette bottom
domain (which contains any part of the cassette lower
than z6 above the horizontal datum plane). At the
nominal wafer center line, a circular hole with a radius
of r7 must be present (up to a height of z5) in the
cassette bottom to avoid interfering with pod latch pins.
For moving the cassette on roller conveyors and for
picking up the cassette with a fork lift, the cassette must
have surfaces on the left and right open to the bottom
and outside bounded by x15, x16, r10, z3 and z4. A
cylindrical section of radius r8 and axis at x11 on the
facial datum plane must be clear up to a height of z22 to
hold the cassette firmly on the lifting forks by the use of
a cylindrical pin.
6.6 Carrier Sensing Pads and Info Pads — When the
cassette is fully down, the carrier sensing pads (shown
in Figure 5) must be z2 above the horizontal datum
plane. It is recommended that the areas surrounding all
of the carrier sensing pads be designed in conjunction
with the features that mate with kinematic coupling pins
so that a mechanical sensor pin cannot interfere with
the lead-in function of the kinematic couplings. Other
sensing pads (called info pads and given letter names)
communicate information about the carrier. Carrier
types that might need differentiation include the open
cassette, the front-opening unified pod (FOUP), the
single-wafer interface (SWIF), and the front-opening
shipping box (FOSB) in both 13-wafer and 25-wafer
capacities (and possibly other capacities if reduced-
pitch versions are later standardized). Note that since
this is a bottom view, the positions of sensors on a load
port will be switched, with the sensor for info pad A on
the right and the sensor for info pad B on the left as one
faces the tool from the front.
6.7 Vertical Dimensions — Figures 6 through 13 show
the vertical dimensions of the cassette. Note that z8 (the
height of the bottom nominal wafer seating plane above
the horizontal datum plane) and z12 (the distance
between adjacent nominal wafer seating planes) are
given as absolute distances with no tolerance. This
means that the sum of actual height variations in the
cassette from the kinematic coupling to the supporting
features holding each wafer must be contained within
the tolerance of z10 with no further stack-up at each
higher wafer. The method for meeting this requirement
is left up to the cassette supplier.
6.7.1 The open space for the wafer set-down volume
consists of a cylindrical section with radius r2 and a
main axis parallel to and y1 in front of the nominal
wafer center line. The top of this cylindrical section is
z11 above the nominal wafer seating plane and its
bottom is z10 above the nominal wafer seating plane.
The implications for wafer positioning of the tolerance
on r2 are as follows. The wafers should be placed in the
cassette within a circle of radius corresponding to the
smaller bound on r2 to avoid touching the edge of the
wafer to the side of the cassette. Once the wafer has
been placed, the cassette must not allow a wafer to
move outside of a circle of radius corresponding to the
larger bound on r2. There are two exceptions to this
limit on wafer movement. When the wafer is pushed
toward the rear of the cassette, the location of the wafer
is defined by the wafer pick-up volume (see Section
6.7.3). When the cassette is gently tilted forward up to
45° , the wafers may slide forward, but it is recom-
mended that they not extend further than y20 from the
facial datum plane. This may be accomplished by
designing the teeth supporting the wafers to include a
“wafer stopper” at the front (as shown in Figure 11) that
is outside of r2 and under z29. Note that use of this
feature will reduce the height of the wafer extraction
volume.
6.7.2 The open space for the wafer extraction volume
includes a cylindrical section with radius r3 and a main
axis parallel to and y1 in front of the nominal wafer
center line. The top of this cylindrical section is z11
above the nominal wafer seating plane and its bottom is
z23 above the nominal wafer seating plane. The wafer
extraction volume also includes the extrusion out the
front of the cassette of this cylindrical section and the
portion of the wafer set-down volume above z29. The
implications for wafer extraction of the definition of
dimension r3 (r3 ≥ r2 + 1) are as follows. The cassette
must give an extra 1 mm (0.04 in.) of horizontal
clearance once the wafer is picked up from wherever it
ends up (within the bounds of r2) after transport in the
cassette.
SEMI E1.9-0701
E2
© SEMI 1994, 2004 7
x
17 =17.5
x
14 =118.5
y19
=61.1
y
17
=27.5
x
13 =88.5
front side of the cassette where wafers are accessed
carrier sensing
pads
facial
datum
plane
bilateral datum plane
y
10
=123.5
y
9
=92.5
y18 =40.2
r
13
≥
2.5
r13
≥
2.5
r13
≥
2.5
x
21 =30
x
22 =70
r14
≥
7.5
info pad B
info pad C
info pad A
r17
≥
10
x
8 =12.5
info pad D
Figure 5
Carrier Sensing Pads in Bottom View
horizontal
datum
plane
z
8
=33
z
18
≤
30
(to top)
z
15
≥
13
z
6
≤
21
z
12
=10
cross-
section in
Figure 1
detail in
Figure 7
detail in
Figure 8
y
11
≤
85
y
15
≤
95
y
16 =155 ±1
y
6
≤
152
y
23
≤
140
y
5
≥
120
y
4
≤
85
facial datum plane
r
6
≤
157
Figure 6
Side View of Cassette
SEMI E1.9-0701
E2
© SEMI 1994, 2004 8
facial datum plane
z14 =1±1
z18 ≤30
(to top of
cassette)
z21 =9±1
z13 =24±1
top
nominal
wafer
plane
z17
=26±1
y8 =2±0.5
y7 =2±0.5
y2 =10±1y3 =10±1
cross-section in
Figure 10
z24 =4±1
(to top of
flange)
z16 =9±1
Figure 7
Top Side View Detail
z
5
≥
10
z
3
=7±1
z
9
=45±1
z
22
≥
20
z
19
=24
z
7
=35±1
horizontal datum plane
z
6
≤
21
z
4
=15±1
z
1
≥
0
z
2
≤
2
(at sensor pad)
z
20
=60±1
r
9 =2.5±0.5
r
8 =7.5±1
facial datum plane
y
2 =10±1
y
3 =10±1
r
7
≥
15
cross-section in Figure 11
Figure 8
Bottom Side View Detail