Carrier lifetime is a primary quality control parameter for silicon wafers in PV applications. The WML models, WML-1 & WML-3, Lifetime Testers allow measurement of wafers “on the fly," i.e., conveyor belt does not stop during measurement. Therefore, they have the high throughput that meets the requirements of in-line quality control in fully automated wafer and cell production lines.
SYSTEM SPECIFICATIONS:
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measurement technique:
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µ-PCD |
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sample size:
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100 to 210mm |
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lifetime range:
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0.1-1000µs |
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repeatability:
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3% |
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measured spot diameter:
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3mm |
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probe height above transport belt:
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4mm |
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wafer vertical position tolerance:
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<300 µm peak to peak, including vibration |
| number of line scans: |
1 (WML-1) or 3 (WML-3) |
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measurement position:
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adjustable |
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sample support:
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on belt |
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system dimensions:
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135mmx460mmx403mm (WxHxD) |
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sample throughput:
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35 point line scan on a 156x156mm wafer, with belt speed of 250 mm/s |
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Additional configurations available if needed
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| IN-LINE APPLICATION: |
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Incoming wafer inspection and sorting |
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After emitter diffusion: efficiency prediction |
CONFIGURATION OF A SYSTEM : |
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WML measurement module (incl. 1-3 lifetime measurement heads)
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| • |
Industrial PC (Windows operating system) and peripherals
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Interface (hardware & software) to automation |
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