METHOD TO CONTROL DEFECT STRUCTURE OF EPITAXIAL SILICON LAYERS ON DIELECTRIC SUBSTRATES Russian patent published in 2014 - IPC H01L21/66 

FIELD: measurement equipment.

SUBSTANCE: in the method to control defect structure of epitaxial silicon layers on dielectric substrates, including preparation of the sample surface, exposure to radiation with wave length λ=380÷630 nm to a sample, rotating around the vertical axis and moving in the horizontal direction relative to the falling radiation, registration of amplitudes of the recorded signal, calculation of relative defect structure of the epitaxial layer N_def and comparison of the calculated value N_def with the available value N_{def (ref)} of the comparison reference, the sample is exposed to pulses with duration of τ₁=50÷100 mcs and porosity τ₂=250÷500 mcs, the recorded signal is the amplitude U_out of the induced photo-EMF in the epitaxial layer of silicon, and relative defect structure of the epitaxial layer is calculated based on the ratio: $$U_{out}/U_{out(\min )}=N_{def(эт)}/N_{def},$$ where U_out(min) - minimum of the recorded values U_out.

EFFECT: high efficiency of measurements and valid assessment of concentration of defects in volume of an epitaxial silicon layer at the border of silicon-sapphire.

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