Title :
Transient Ion Drift Measurements of Polycrystalline CdTe PV Devices
Author :
Enzenroth, R.A. ; Barth, K.L. ; Sampath, W.S.
Author_Institution :
Dept. of Mech. Eng., Colorado State Univ., Fort Collins, CO
Abstract :
The well known transient ion drift (TID) method is used to quantify the density of mobile Cu interstitial ions in polycrystalline CdTe PV cells. Average Cui + ion densities in optimally processed cells are 20% of the background ionized acceptor doping level. A preliminary estimate of the diffusion coefficient for Cu i + ions in the polycrystalline CdTe absorber is D(Cui)=1.3E-6 [cm2/sec] times exp[-0.29 eV/(KB*T)] in the temperature range of 25degC to 55degC from TID measurements. Aspects of the TID method as pertains to practical thin film polycrystalline devices are discussed
Keywords :
II-VI semiconductors; cadmium compounds; copper; diffusion; impurity states; interstitials; photovoltaic cells; semiconductor thin films; 25 to 50 C; CdTe:Cu+; background ionized acceptor doping level; diffusion coefficient; mobile Cu interstitial ion density; polycrystalline absorber; polycrystalline semiconductor PV cells; thin film polycrystalline semiconductor PV devices; transient ion drift measurements; Capacitance; Coatings; Costs; Density measurement; Fabrication; Grain boundaries; Laboratories; Mechanical engineering; Mechanical variables measurement; Thin film devices;
Conference_Titel :
Photovoltaic Energy Conversion, Conference Record of the 2006 IEEE 4th World Conference on
Conference_Location :
Waikoloa, HI
Print_ISBN :
1-4244-0017-1
Electronic_ISBN :
1-4244-0017-1
DOI :
10.1109/WCPEC.2006.279487
