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Single crystal cultured quartz substrate wafer is most commonly specified as 3" or 100 mm with a reference flat. The wafers are Y-cut with rotations specified between about 32° and 42.75° around the X-axis. A high quality, low damage surface is prepared on one major (propagating) surface by polishing. The back side is usually lapped to a rough finish to attenuate unwanted vibration modes.
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Ex-stock delivery for standard 4" wafer angles : 32°, 34°, 36°, 37°30', 38° and 40°.
| Description | Unit |
Tolerance |
76.2 ~ 100mm |
|
| Diameter | mm |
±0.1 |
76.2 ~ 100.0 |
|
| Thickness | mm |
±0.01 |
0.35 - 0.50 |
|
| Total thickness variation | mm |
maximum |
4.00 |
|
| Orientation of propagating surface | around X-axis |
arc minute |
± 6 |
Customer specified |
around Z´-axis |
arc minute |
± 15 |
0.00 |
|
| Reference fiat width | mm |
± 3 |
22/32 |
|
| Reference fiat orientation (xxxx to Y´-axis) | arc minute |
± 6 |
0 |
|
| Segment | mm |
nominal |
74.7 / 98.5 |
|
| Xseed | mm |
minimum |
76 |
|
| A | mm |
maximum |
2 / 5 |
|
| Centricity of seed | mm |
within central 5 |
are also available in any of the above dimensions and angles.
| Description | Unit |
Tolerance |
76.2 ~ 100mm |
|
| Roughness | Rrms - Propagating surface |
nm |
maximum |
0.6 |
Ra - Back side |
nm |
±50 |
250 |
|
| Bow | µm |
maximum |
40 |
|
| Scratch length | µm |
maximum |
10 |
|
| Dig diameter | µm |
maximum |
2 |
|
| Observable flaws | count |
maximum |
2 |
|
| Pin holes (at the seed) | count |
maximum |
0 |
|
| Dimensions of chips | within 1.5mm of edge |
mm |
maximum |
0.5 |
on the circular segment on the reference fiat |
mm |
maximum |
0.2 |
|
| Wafer edge treatment (not including reference fiat) | mechanical bevel | |||
Rrms: Root Mean Square Ra: Average Peak-to-Valley Distances |
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| Description | Unit |
Tolerance |
76.2 ~ 100mm |
|
| Growth type | Basal (Z) |
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| Handedness | right or left |
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| Twins | none |
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| α - value (3500 cm1) | α - units |
maximum |
0.060 |
|
| Inclusions (diameter) | 25 - 75 µm |
cm3 |
maximum |
5 |
75 - 100 µm |
cm3 |
maximum |
4 |
|
> 100 µm |
cm3 |
maximum |
3 |
|
| Etch channel density | cm2 |
maximum |
300 |
References
International Electrotechnical Commission Standard, CEI/IEC 758, Second edition, 1993-04.
Institute of Electrical and Electronic Engineers Standard on Piezoelectricity ANSI/IEEE Std. 176-1987.
Reproduced by kind permission of Sawyer Research Products, Inc.© Sawyer Research Products, Inc. Specifications subject to change without notice.All rights reserved ©Vides.Web Roditi International 2004