Application
SI WAFER SORTING
Sorter applications provide advanced multiparameter wafer inspection with integrated high speed sorting for quality control of production PV wafers. Owing to wide range automation module portfolio and flexible combined Semilab’s metrology modules, all customer can find perfect configuration what fulfil their production expectations.
Application area:
- Outgoing wafer inspection for wafer manufacturers
- Incoming as-cut wafer inspection for solar cell manufacturers
Sorter purpose
- Eliminating damaged wafers from further process
- Eliminating high thickness variation wafers (TTV, saw mark)
- Sorting of potentially weak wafers (microcracks) which could break in subsequent process steps
- Sorting based on resistivity, and lifetime values
- Sorting of wafers with dislocations, high contamination and vacancy density
- Wafer input: loading from cassettes or stack
- Wafer output: Sorting in different user-defined classes, collection in coin stacks
- High throughput
Technology
µ-PCD CARRIER LIFETIME FOR WAFERS
Microwave detected PhotoConductance Decay (µ-PCD) Carrier lifetime measurement is a widely accepted technology for incoming wafer inspection, quality control and process monitoring in wafer manufacturing as well as in solar cell manufacturing. The microwave induced photoconductive decay method is the most common way of measuring minority carrier lifetime in silicon. This method excels due to its reliability, good reproducibility and the short measurement time that permits of making lifetime scans with high resolution.
As-cut wafer
µ-PCD technique
It is a metrology of recombination properties and defects used in silicon photovoltaics and IC manufacturing as well. The technology is based on pulse of laser light, which generates carriers. Excited carriers change the conductivity of semiconductor. The microwave reflection is sensitive to change in conductivity measured signal shows decaying of conductivity. The objective of the monitoring is the bulk lifetime parameter, because that gives information about the contaminations and dislocations.
The main application in wafer sorting is to detect highly contaminated wafers which would result in low efficiency final solar cell. Due to the fact that solar wafers are thin and have high surface recombination the method is applicable to detect highly contaminated areas of wafers and it is not applicable to qualify the high quality materials. Other measuring techniques are also limited by high surface recombination in as cut wafer level application. Once the surface is passivated in the cell manufacturing process new possibilities open up in the application of the µ-PCD technique.
FEATURES
- Suitable material to measure:
- Monocrystalline
- Multicrystalline
- String ribbon
- Parameter free, non-contact method, suitable for mapping
- High lateral resolution
- Multiple line measurement (option)
Product Line
PVS
The PVS product line provides advanced multi-parameter wafer inspection with integrated high speed sorting for quality control of production wafers. It eliminates imperfect substrates, maximize cell line output and ensures optimized efficiency.
It combines high reliability wafer handling with Semilab’s industry leading PV metrology, to provide a turnkey solution for sorting of incoming wafers. This is backed by direct expert support from the OEM metrology manufacturer, through our worldwide network of branch offices.
Products
PVS-5100
PVS-5100 is a high throughput, field proven PV Wafer Inspection and Sorting System.
It combines high reliability wafer handling with Semilab’s industry leading PV metrology, to provide a turnkey solution for sorting of incoming wafers. This is backed by direct expert support from the OEM metrology manufacturer, through our worldwide network of branch offices.
Loaders
- PVLS-5400 Automated stack loader with 3 position pick-and-place system. Up to 2400 pcs buffered wafer in 12 pcs carrier.
- PVLC-3600* Automated cassette loaders for 25/50/100 slot cassettes
- PVLC-3600-AL Fully automated production line loader for 100 slot cassettes
Metrologies
- PLI-101/3 Photoluminescence imaging
- WML-1 Minority carrier lifetime measurement
- SHP-200 2D measurement
- MCI-150 Micro crack inspection
- WSI-120 Surface chipping and contamination inspection
- TTR-300 Thickness, resistivity measurement
- TTR-300 Saw mark Inspection
Unloaders
- PVULS-5406T High speed stack unloader with 6 bin
- PVULS-5407T High speed multilevel stack unloader with 7 bin
PVS-6000
PVS-6000 is a High Speed, field proven PV Wafer Inspection and Sorting System with 5400 wafer per hour throughput. It combines high reliability wafer handling with Semilab’s industry leading PV metrology, to provide a turnkey solution for sorting of incoming wafers. This is backed by direct expert support from the OEM metrology manufacturer, through our worldwide network of branch offices.
Loaders:
- PVLS-5400 Automated stack loader with 3 position pick-and-place system. Up to 2400 pcs buffered wafer in 12 pcs carrier.
- PVLC-3600 Automated cassette loaders for 25/50/100 slot cassettes
- PVLC-3600-AL Fully automated production line loader for 100 slot cassettes
Metrologies:
- PLI-101/3 Photoluminescence imaging
- WML-1 Minority carrier lifetime measurement
- SHP-200 2D measurement
- MCI-150 Micro crack inspection
- WSI-120 Surface chipping and contamination inspection
- TTR-300 Thickness, resistivity measurement
- TTR-300 Sawmark Inspection
Unloaders:
- PVULS-5406T High speed stack unloader with 6 bin
- PVULS-5407T High speed multilevel stack unloader with 7 bin