Troubleshooting manufacturing process needs more comprehensive analysis of the wafers in different process steps. Often these tests are out of scope of in-line and offline process control tools. For this purpose Semilab can offer state-of-the art laboratory tools with multiple capabilities.
These advanced metrology tools can be effectively used in the research and development field to introduce new methods and techniques for high efficiency solar cell production.
Semilab is open for cooperation with customers to improve the tool performance and introduce new applications to cover future metrology needs.
The measurement tools were designed to achieve good tool performance, user-friendly operation and low cost of ownership.
The applications include the following:
The quantum efficiency of the solar cell in the photovoltaic industry is one of the most important indicator. It is given as the ratio of the induced electron current (Ielectron) of solar cell and the incident photon current (Iphoton) and depends on the light wavelength and the number of solar cell properties. There are two different quantum efficiency definitions:
Quantum efficiency of solar cell is limited by different losses:
Reliable method of obtaining of IQE value is Light Beam Induced Current (LBIC) method of measurement.
LBIC technology is based on the electrical current measurement. Laser beam is shined on the sample in one point and creates electrical current which is measured by the tool and represents the short circuit current (ISC) at the given illumination. The reflection (R) of the multiple laser source is sensed by reflection detector. From the ISC and reflection values can be determined the IQE. Using multiple wavelengths, the diffusion length (L) can be measured. The theory is similar to the SPV technique:
LBIC application examples:
|980 nm IR laser:|
|405 nnm Blue laser:|
The WT product line is a powerful measurement platform for performing many different semiconductor material characterization measurements. The base system includes all the overhead functions necessary to perform characterization measurements, including power supplies, computer and operating software, XY measurement stage, etc.
The WT-2000 is typically used to make maps, where the wafer is scanned at a programmable raster. Each system is configured to the user’s requirements by adding treatment and measurement capabilities.
The world’s most powerful PV metrology system. Unparalleled mapping, precision, repeatability and tool matching
Features and System specifications:
It is a new integrated platform with the following capabilities:
Other testing capabilities:
The WT-2000PVN is a table top measurement system, capable of performing a variety of measurements on PV cells, wafers, and blocks. The base system includes the overhead functions, and you configure the measurement capabilities to match your specific needs, by selecting from the options below.
The WT-2000PVN can measure blocks and ingots, as well as wafers and cells. For measuring wafers and cells, people typically produce maps. When measuring blocks or ingots, people often produce only line scans, to save time, WT-2000PVN can do both.
Most producers of PV cells own a WT-2000PVN. It is extremely useful for:
Measurement techniques that can be integrated in WT-2000PVN: