J. Tousek et al., Improved photovoltaic method for measurement of minority carrier diffusionlength applied to silicon solar cells, SOL EN MAT, 69(3), 2001, pp. 297-302
The photovoltage spectrum measured on back illuminated silicon solar cells
of the PESC (passivated emitor solar cell) type without original bottom ohm
ic electrode is evaluated with the aim to find the diffusion length of mino
rity carriers in bulk of the absorber (L). Two junctions, namely pn(+) junc
tion of the cell and that spontaneously created on the free surface general
ly exist in such samples. They give rise to two signals of opposite signs w
ith one point of exact compensation. Six parameters (including L) are neede
d to characterize the spectrum. Special simple arrangement removes influenc
e of spontaneously created junction on the free surface, which, in this way
, reduces the number of parameters needed for fitting to three and enhances
reliability of the measurement. (C) 2001 Elsevier Science B.V. All rights
reserved.