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LGS
 
Langasite crystal La 3 Ga 5 SiO 14 , has been investigated for laser device since 1980 ¡¯ s. However, it was found excellent for BAW and SAW devices due to its excellent acoustic characteristics. Langasite has 3~4 times larger electro-mechanical coupling coefficient than quartz, better frequency-temperature characteristics and smaller equivalent series resistance.
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Typical Physical Properties: |
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Crystal Structure |
trigonal system, group 33. a= 8.1783 c = 5.1014 |
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Growth Method |
Czochralski |
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Moh ¡¯ s Hardness |
6.6 |
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Density |
5.754 g /cm 3 |
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Melt Point |
1470 ¡æ ( phase transition point: N/A) |
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Thermalexpansion (x10-6/ ¡æ ) |
¦Á 11 : 5.10 ¦Á 33 : 3.61 |
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Acoustic velocity, SAW |
2400 ( m/sec ) |
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Frequency constant, BAW |
1380 ( kHz/mm ) |
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Piezoelectric coupling |
K square(%) BAW: 2.21 SAW: 0.3 |
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Inclusion |
N0 |
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Standard Wafer Specifications: |
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Orientation |
orientation specified by customer. ¡À 0.5 ¡ã |
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Polished surface |
EPI polished on one side or two sides to Ra < 10A
Working Area: Wafer diameter minus 2 mm
BOW: < 10 um for 2 ¡å wafer
No chips out on working area. In the edge, chip width < 0.5 mm
Pit and scratches: < 3 per wafer or < 20 per 100 wafers |
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Standard Thickness |
0.5 mm ¡À 0.05mm TTV < 5 um |
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Standard Diameter |
35 ( mm ) ¡À 0.2 mm |
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We can provide specific directional and dimensions and according to demand. |
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