Title :
Capacitance measurements on ZnO/CdS/Cu(In1-xGa)Se2 solar cells
Author :
Wang, H.P. ; Shih, I. ; Champness, C.H.
Author_Institution :
Dept. of Electr. & Comput. Eng., McGill Univ., Montreal, Que., Canada
Abstract :
Capacitance-voltage (C-V) and deep level transient spectroscopy (DLTS) measurements have been carried out on heterojunction ZnO/CdS/Cu(In1-xGax)Se2 solar cells with different Ga content. These cells were fabricated on polished monocrystalline samples prepared by the Bridgman method. The C-V measurements indicated a significant effect of interface or surface states, especially for the non-annealed samples. Different hole deep levels and different shapes of DLTS spectrum were found in Cu(In1-xGax)Se2 crystals with different Ga content. It is believed that Ga content has a great impact in the formation of deep levels in Cu(In1-xGax)Se2 crystals. The DLTS results combined with the conversion efficiencies of the solar cells indicate the interfacial states could dominate the cell performance rather than the deep levels in the semiconductor.
Keywords :
II-VI semiconductors; cadmium compounds; capacitance; copper compounds; deep level transient spectroscopy; deep levels; gallium compounds; indium compounds; interface states; solar cells; ternary semiconductors; zinc compounds; Bridgman method; C-V measurements; DLTS spectrum shapes; Ga content; ZnO-CdS-Cu(In1-xGa)Se2; ZnO/CdS/Cu(In1-xGa)Se2 solar cells; capacitance-voltage measurements; conversion efficiencies; deep level formation; deep level transient spectroscopy; heterojunction solar cells; hole deep levels; interface states; polished monocrystalline samples; surface states; Annealing; Capacitance measurement; Capacitance-voltage characteristics; Frequency dependence; Frequency measurement; Photovoltaic cells; Substrates; Transistors; Voltage; Zinc oxide;
Conference_Titel :
Photovoltaic Specialists Conference, 2002. Conference Record of the Twenty-Ninth IEEE
Print_ISBN :
0-7803-7471-1
DOI :
10.1109/PVSC.2002.1190675
