Title :
AC analysis of temperature effects on conversion efficiency of CuInGaSe2 solar cells
Author :
Hong Tak Kim ; Chang Duk Kim ; Maeng Jun Kim ; Young-Soo Sohn
Author_Institution :
Dept. of Phys., Kyungpook Nat. Univ., Daegu, South Korea
Abstract :
The temperature effect on a CuInGaSe2 (CIGS) solar cell was investigated in the temperature range -10 to 80°C using direct current (DC) and alternating current (AC) characteristic analysis of CIGS solar cells. The change rates of short-circuit current density (Jsc), open-circuit voltage (Voc), fill factor (FF) and efficiency (η) with respect to temperature were investigated. In addition, the variation of impedance, total capacitance and dynamic resistance due to the temperature change implied that the width of the depletion region in a p-n junction shrank, and the effective minority carrier lifetime (τeff) decreased. Consequently, Jsc changed slightly due to the balance between the variation of the energy bandgap (Eg) and τeff. However, Voc linearly decreased due to the relationship of Eg when the temperature increased. From these results, it has been concluded that Voc plays an important role in the characteristics of the CIGS solar cell with change of temperature.
Keywords :
carrier lifetime; copper compounds; current density; gallium compounds; indium compounds; minority carriers; p-n junctions; short-circuit currents; solar cells; ternary semiconductors; AC analysis; CIGS solar cell; CuInGaSe2; alternating current characteristic analysis; conversion efficiency; direct current characteristic analysis; dynamic resistance; energy bandgap; fill factor; minority carrier lifetime; open-circuit voltage; p-n junction; short-circuit current density; temperature -10 C to 80 C; temperature effects;
Journal_Title :
Electronics Letters
DOI :
10.1049/el.2014.3257
