*Effects of heavy doping and impurity size on minority-carrier transport parameters in heavily (lightly) n(p)-type crystalline silicon at 300K, applied to determine the performance of n^+-p junction solar cells, by H. Van Cong, P. Blaise, and O. Henri-Rousseau*

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**Author(s)**

**Abstract**

The effects of heavy doping and donor (acceptor) size on the hole (electron)-minority saturation current density J_Eo (J_Bo ), injected respectively into the heavily (lightly) doped crystalline silicon (Si) emitter (base) region of n^+-p junction, which can be applied to determine the performance of solar cells, being strongly affected by the dark saturation current density: J_o≡J_Eo+J_Bo, were investigated. For that, we used an effective Gaussian donor-density profile to determine J_Eo, and an empirical method of two points to investigate the ideality factor n, short circuit current density J_sc, fill factor (FF), and photovoltaic conversion efficiency η, expressed as functions of the open circuit voltage V_oc, giving rise to a satisfactory description of our obtained results, being compared also with other existing theoretical-and-experimental ones. So, in the completely transparent and heavily doped (P-Si) emitter region, CTHD(P-Si)ER, our obtained J_Eo-results were accurate within 1.78%. This accurate expression for J_Eo is thus imperative for continuing the performance improvement of solar cell systems. For example, in the physical conditions (PCs) of CTHD (P-Si) ER and of lightly doped (B-Si) base region, LD(B-Si)BR, we obtained the precisions of the order of 8.1% for J_sc, 7.1% for FF, and 5% for η, suggesting thus an accuracy of J_Bo (≤8.1%). Further, in the PCs of completely opaque and heavily doped (S-Si) emitter region, COHD(S-Si)ER, and of lightly doped (acceptor-Si) base region, LD(acceptor-Si)BR, our limiting η-results are equal to: 27.77%,…, 31.55%, according to the E_gi-values equal to: 1.12eV ,…, 1.34eV, given in various (B,…, Tl)-Si base regions, respectively, being due to the acceptor-size effect. Furthermore, in the PCs of CTHD (donor-Si) ER and of LD(Tl-Si)BR, our maximal η-values are equal to: 24.28%,…, 31.51%, according to the E_gi-values equal to: 1.11eV ,…, 1.70eV , given in various (Sb,…, S)-Si emitter regions, respectively, being due to the donor-size effect. It should be noted that these obtained highest η-values are found to be almost equal, as: 31.51%≃31.55%, coming from the fact that the two obtained limiting J_o-values are almost the same.

**Keywords**

donor (acceptor)-size effect; heavily doped emitter region; ideality factor; open circuit voltage; photovoltaic conversion efficiency

**Cite this paper**

H. Van Cong, P. Blaise, O. Henri-Rousseau,
Effects of heavy doping and impurity size on minority-carrier transport parameters in heavily (lightly) n(p)-type crystalline silicon at 300K, applied to determine the performance of n^+-p junction solar cells, by H. Van Cong, P. Blaise, and O. Henri-Rousseau
, *SCIREA Journal of Physics*.
Volume 4, Issue 4, August 2019 | PP. 63-110.

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