Title :
An experimental and computer simulation study of the role of CdS in CIS-type solar cells
Author :
Hou, Jingya ; Fonash, Stephen J. ; Kessler, John
Author_Institution :
Electron. Mater. & Process. Res. Lab., Pennsylvania State Univ., University Park, PA, USA
Abstract :
An experimental and computer simulation study of the “red kink” current-voltage features seen in many CdS/Cu(In,Ga)Se2 solar cells has been undertaken to gain more insight into cell operation and to address the controversy over the role of the CdS layer. The study shows that in structures with chemical bath deposited CdS: (1) the “red kink” effect is due to a low free electron concentration and high trap state concentration in the CdS layer, (2) the direct cause of the “red kink” is current modulated free electron concentration in the CdS, and (3) under white light the positive space charge built-up in CdS traps greatly enhances the photo-carrier collecting electric field in the absorber layer. Therefore, the CdS layer has an important role in the junction under white light
Keywords :
II-VI semiconductors; cadmium compounds; copper compounds; electric current measurement; indium compounds; power engineering computing; simulation; solar cells; space charge; ternary semiconductors; voltage measurement; CIS-type solar cells; CdS; CdS-Cu(InGa)Se2; CdS/Cu(In,Ga)Se2 solar cells; absorber layer; cell operation; chemical bath deposited CdS; computer simulation; current modulated free electron concentration; high trap state concentration; low free electron concentration; photo-carrier collecting electric field; positive space charge; red kink current-voltage features; white light; Chemicals; Computer simulation; Electron traps; Energy conversion; Laboratories; Lighting; Microelectronics; Optical modulation; Photovoltaic cells; Space charge;
Conference_Titel :
Photovoltaic Specialists Conference, 1996., Conference Record of the Twenty Fifth IEEE
Conference_Location :
Washington, DC
Print_ISBN :
0-7803-3166-4
DOI :
10.1109/PVSC.1996.564289
