Case Studies|Overview

There is a wide variety of application for minority carrier lifetime measurement tools. Case studies and examples are added constantly.

Recent Case Studies

Iron concentration determination

The exact determination of the iron concentration is very important, since iron is one of the most abundant and also most detrimental defects in silicon. With the MDPingot tool it is possible to measure the iron concentration in an ingot inline and the laboratory tool MDPmap09 also enables very high resolution maps of the iron concentration.

related Products: MDP ingot , MDP map related Branches: Photovoltaic , Semiconducter industry

 


Trap concentration determination

The method MDP can also be applied to measure injection dependent photoconductivity and lifetime. At low injection the lifetime as well as the excess photoconductivity shows an anomalous increase which can be explained by the effects of trapping centers. With MDPmap09 it is possible to measure injection dependent lifetime curves and to determine the trap density and activation energy.

related Products: MDP map related Branches:

 


Injection dependent measurements

The minority carrier lifetime is strongly dependent on the injection (excess carrier concentration). From the shape and height of the lifetime curve information about the dominant recombination center as well as trapping center can be deduced. With MDPmap09 it is possible to measure not only injection dependent lifetime curves but also photoconductivity curves over a very wide range of injection.

related Products: MDP map related Branches:

 


p/n detection

Changes in the conduction type of a multicrystalline ingot are frequent, since a high co dopant concentration is typical for the low quality feedstock, that is used in PV industry. With the MDPingot tool it is possible to detect pn-changes with a 1 mm resolution.

related Products: MDP ingot related Branches: Photovoltaic

 


Passivation homogeneity

For many applications samples may exhibit a passivated surface. With MDPmap09 it is possible to investigate the quality and homogeneity of the passivation with a high resolution.

related Products: MDP inline , MDP map related Branches:

 


Highly spatial resolved inline metrology on Multicrystalline Silicon

Non-destructive measurements of minority carrier lifetime are well established and widely used for process control and characterization of defects in crystalline silicon. With our novel tools MDPingot and MDPinline it is possible to map the minority carrier lifetime with a so far unsurpassed combination of spatial resolution, sensitivity and measurement speed.

Correlations with shunts and other crystallographic defects demonstrate the potential of these tools, e.g. investigation of passivation homogeneity, statistical monitoring and process control or monitoring of furnace properties.

related Products: MDP inline , MDP ingot related Branches:

 


Lifetime determination of epitaxial silicon thin-film layers

The method MDP enables to determine the minority carrier lifetime of crystalline silicon thin-film material, deposited as epitaxial layers down to a thickness of about 10 µm. The measurement is contact less and non-destructive. The investigations provide information about the electrical quality of the layer and the deposition process. Even the analysis of the interface recombination velocity should be possible.

related Products: MDP map related Branches: Photovoltaic , Semiconducter industry

 


Determination of the activation energy of defects in semiconductors

With the MD-PICTS method information about the defect contingent of semiconductor materials can be gained. The investigations are contact less and non-destructive. By conducting measurements at different temperatures in the range of 80 to 400 K and using an appropriate analysis technique the activation energies of trapping defects in the material can be determined. This can be used to identify dominant defects.