Intermediate-band optoelectronic transitions in ZnTeO
for high-efficiency solar energy conversion
•
ZnTe:O provides intermediate states
and bandgap at near optimal energy
Intermediate band behavior observed
in ZnTe:O, with long carrier lifetime
Enhanced response observed in ZnTe:O
below ZnTe bandedge, higher short
circuit current
High efficiency requires better junction
•
•
•
Time-resolved PL (W. Metzger at NREL)
long carrier lifetime at O states
Photon Counts
10
~4s
700nm, 1.8eV
10
2
10
1
10
0
10
<100ps
550nm, 2.25eV
ZnTe:O
O-States
ZnTe
T=300K
ZnTe
AM1.5
ZnTe:O
700nm
550nm
-10
10
-9
10
-8
10
-7
10
-6
10
Photo of prototype
ZnTe:O solar cell
Response below bandedge in ZnTe:O solar cell and enhanced
short circuit current density in comparison to ZnTe
Response (Arb. Units)
2m ZnTe:O on GaAs
3
Absorption bands for
Intermediate states
-5
Time (sec)
J. Phillips, University of Michigan
1.0
1.5
2.0
2.5
Energy (eV)
3.0