Photocapacitance study of deep levels in thin CdTe PV devices

Manufacturing Process Optimization to Improve Stability, Yield and Efficiency of CdS/CdTe PV Devices: Final Report, December 2004 - January 2009

“…A vacuum bag with an accumulator was used in these studies. In this approach, the glass/EVA/glass is placed in 5 the vacuum bag and the bag with the accumulator is evacuated and placed in the furnace. The purpose of the accumulator is to provide a vacuum reservoir for the gases that are evolved during the encapsulation to accumulate.…”

Photocapacitance measurements in irradiated a-Si:H based detectors

“…Recently, several defect levels were identified by temperature-dependent spectral photocapacitance measurements in single films of ZnO [4] and CdTe [5]. Other authors applied this technique to complete amorphous silicon based p-i-n solar cells and described a combination of photocapacitance measurements and solar cell parameter measurements, combined with a computer model to show that under strong illumination the photocharge increases inside the solar cell and causes field collapse and thus a decline in solar cell efficiency [6].…”

The effect of copper on the sub-bandgap density of states of CdTe solar cells

“…Steady-state photocapacitance has revealed a signal attributed to a 0.9 eV defect in devices without intentional Cu doping. 18 The cause for this discrepancy is unclear. It is possible that the TPC spectra presented here are not sensitive enough to detect this defect state, or that there was unintentional Cu contamination affecting the steady-state photocapacitance results.…”