High Performance from Topsil PV-FZ Silicon
Substrates
The silicon wafer manufacturer, Topsil, has developed a PV grade
FZ silicon material with a cost structure reported as close to
standard CZ materials. At UNSW, the PERL (passivated
emitter, rear locally-diffused) cells have been fabricated
on these Topsil PV-FZ substrates with bright etched planar surfaces
to test the quality of these substrates. The table below lists
the performances of some of these cells.
ID
|
Voc (mV)
|
Jsc (mA/cm2)
|
FF (%)
|
Eff (%)
|
| Wp-04-4a |
707
|
37.0
|
82.2
|
21.5
|
| Wp-04-4b |
706
|
37.7
|
82.6
|
22.0
|
| Wp-04-5f |
702
|
38.0
|
82.6
|
22.0
|
| Wp-04-6f |
702
|
38.3
|
81.3
|
21.9
|
Performance of ZnS/MgF2 double layer
antireflection coated planar PERL cells on Topsil’s PV-FZ
substrates as measured at UNSW according to Sandia calibrated
PERL cells under 100mW/cm2 global spectrum.
These planar PERL cells demonstrated very high Voc of
707 mV which is only a few millivolts below our record for double-layer
AR coated cells. This result confirms that the Topsil PV-FZ materials
have the same high quality as the best FZ materials.
These cells also gave very high current densities
and high fill factors. If the surface was textured, the cells have
potential energy conversion efficiencies well above 24%. |
