Micromagnetic technology for detection of carbon impurity in crystalline silicon

• Micromagnetic method for detecting traces of carbon impurity in crystalline silicon.
• The micromagnetic detection was based on the geomagnetic field.
• Micromagnetic decay theory was gained according to the energy decay.
• Apparent magnetic susceptibility parameter was calculated.

This paper proposes a method of lossless micromagnetic detection in the geomagnetic field for detecting traces of carbon impurity defects in crystalline silicon. The magnetization tests show that crystalline silicon is a diamagnetic substance with a stronger relative permeability than carbon. Micromagnetic decay theory is gained according to the energy decay. When the geomagnetic field penetrates through the materials, the apparent magnetic susceptibility can be calculated and subsequently used to project the images. The resulting image clearly showed the location of the defects. Test results are proved by the metallographic phase and spectral analysis. New method and ideas are provided for effective detection of trace carbon impurity defects in the crystalline silicon.