Growth and process optimization of CdTe and CdZnTe polycrystalline films for high efficiency solar cells

Development of thin‐film Cu(In,Ga)Se2 and CdTe solar cells

“…However, special annealing treatments significantly improve the cell efficiency, in some cases the increment is up to three times the initial value. Therefore, it has become common routine 123,124 that CdTe/CdS stacks are subjected to heat treatments under Cl-containing ambient at temperatures between 350 and 600 C. Furthermore, the presence of oxygen during annealing is beneficial. 125 This annealing procedure in Cl-O ambient is called 'CdCl 2 treatment' or 'junction activation.'…”

“…134,135 In particular, the grain boundary regions become more p-doped, owing to preferred grain boundary diffusion and segregation of Cl and O, and an increased photo-carrier collection efficiency is measured. [136][137][138] A decrease in interface states after the CdCl 2 treatment is commonly reported, that changes the mechanism of current transport from tunneling/interface recombination to junction recombination in case of CSS deposition. 136,139 Whether this is due to S diffusion or Cl incorporation is unclear.…”

“…[136][137][138] A decrease in interface states after the CdCl 2 treatment is commonly reported, that changes the mechanism of current transport from tunneling/interface recombination to junction recombination in case of CSS deposition. 136,139 Whether this is due to S diffusion or Cl incorporation is unclear. The diffusion of S may shift the p-n junction away from the metallurgical interface into the CdTe absorber and decrease the CdTe band gap.…”

High Density Nano-Electrode Array for Radiation Detection

“…CZT is considered more advantageous than CdTe in radiation detection because of wider band gap and higher resistivity, which provides low noise level during detection. Further, Cd1−xZnxTe with x = 0.04-0.07 finds application in infra-red detectors and x < 0.4 in solar cell applications 24 . In order to minimize the leakage current, room temperature radiation detector CZT materials are required to have very high resistivity, in the order of 10 10 Ω-cm.…”

Thin films CdS/CdTe solar cells with different activation processes base layer

“…It is related with growth of grains sizes in CdTe and CdS [6], decrease in the specific resistance of base layer [7]; growth in lifetime of non-equilibrium minor charge carriers [8], change in the mechanism of charge transport [9]. Structural changes occurring after chloride treatment stipulate the recrystallization process in cadmium telluride, since the eutectic temperature of CdTe-CdCl 2 system is (490±5) °С.…”