TY - GEN
T1 - Optical Characterization of Ternary Element Loss during Co-Chloride Passivation of Polycrystalline II-VI Wide-Bandgap Alloys
AU - Reich, Carey
AU - Onno, Arthur
AU - Sampath, Walajabad S.
AU - Holman, Zachary C.
PY - 2019/6
Y1 - 2019/6
N2 - Alloys of the II-VI semiconductor CdTe with Mg or Zn have tunable bandgaps in the range modelled to be optimal for integration as a top cell in a tandem photovoltaic device with a Si bottom cell. Leveraging the low-cost production techniques developed for CdTe, this pairing has the potential to produce low-cost and highly efficient tandem PV cells. However, the CdCl2 post-deposition bulk passivation process widely used for CdTe reduces the concentration of the ternary elements in the absorber, reducing the bandgap from the modelled values, and results in poorer activation than the same process applied to pure CdTe material. We study the mitigation of this loss during CdCl2 treatment by the development of an overpressure of MgCl2 and ZnCl2, thought to be products of the loss reaction, for Cd1-xMgxTe and Cd1-xZnxTe, respectively. Little effect is seen until a vapor pressure far in excess of CdCl2 is achieved, reducing the loss - as measured by transmittance - by half.
AB - Alloys of the II-VI semiconductor CdTe with Mg or Zn have tunable bandgaps in the range modelled to be optimal for integration as a top cell in a tandem photovoltaic device with a Si bottom cell. Leveraging the low-cost production techniques developed for CdTe, this pairing has the potential to produce low-cost and highly efficient tandem PV cells. However, the CdCl2 post-deposition bulk passivation process widely used for CdTe reduces the concentration of the ternary elements in the absorber, reducing the bandgap from the modelled values, and results in poorer activation than the same process applied to pure CdTe material. We study the mitigation of this loss during CdCl2 treatment by the development of an overpressure of MgCl2 and ZnCl2, thought to be products of the loss reaction, for Cd1-xMgxTe and Cd1-xZnxTe, respectively. Little effect is seen until a vapor pressure far in excess of CdCl2 is achieved, reducing the loss - as measured by transmittance - by half.
KW - II-VI semiconductors
KW - Tandem Photovoltaics
UR - http://www.scopus.com/inward/record.url?scp=85081570301&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85081570301&partnerID=8YFLogxK
U2 - 10.1109/PVSC40753.2019.8980642
DO - 10.1109/PVSC40753.2019.8980642
M3 - Conference contribution
AN - SCOPUS:85081570301
T3 - Conference Record of the IEEE Photovoltaic Specialists Conference
SP - 2494
EP - 2497
BT - 2019 IEEE 46th Photovoltaic Specialists Conference, PVSC 2019
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 46th IEEE Photovoltaic Specialists Conference, PVSC 2019
Y2 - 16 June 2019 through 21 June 2019
ER -