METHOD OF DETERMINING QUALITY OF PHOTOVOTAIC p-n JUNCTION Russian patent published in 2009 - IPC G01R31/26 

FIELD: physics.

SUBSTANCE: when determining quality of a photovoltaic junction, a p-n junction is illuminated with monochromatic light with wavelength λ defined by the expression:

where E_g is the band gap of the semiconductor, Ev; E_g.top is the band gap of the semiconductor of the (z-1)^th p-n junction in the solar cell (z is an index number counted from the exposed surface of the p-n junction whose quality is being determined) when z ≥ 2; E_g.top = 1.4 E_g eV, when z = 1. Intensity P of illumination is changed and the resultant open-circuit voltage V_oc is measured for each value of P and the obtained relationship between V_oc and P is approximated. Values of recombinanation and diffusion photovoltaic parametres P_0r and P_0d are determined from the obtained approximated relationship. Forward-bias current with varying density J is then passed through the p-n junction. Intensity of the generated boundary electroluminescence L is measured for each value of J and the relationship between L and J is approximated. From the obtained approximated relationship, values of recombinanation and diffusion electroluminescence parametres k_r and k_d are found and the quality of the photovoltaic p-n junction is determined from the value of recombination saturation current density J_0r and diffusion saturation current density J_0d.

EFFECT: possibility of diagnosing a photovoltaic p-n junction which is part of a multijunction solar cell.

3 dwg