SCHOTT Solar and SCHMID Group
lift PERC Efficiency Records to Values
of up to 21%
New record results demonstrate successful technology transfer between t=
he two partners
20.74% PERC cell with SCHMIDS APCVD Al2O3-Passivation
21.0% PERC cell with optimized screen-printed silver contacts
SCHOTT Solar and the SCHMID Group demonstrate the successful transfer of th=
e latest developments of SCHOTT Solar's passivated rear side contact techno=
logy by achieving new efficiency records for so called PERC solar cells. Us=
ing SCHMID's new APCVD manufacturing equipment to apply a rear side aluminu=
m oxide passivation layer and employing SCHOTT Solar's improved emitter tec=
hnology a cell efficiency of 20.74% was reached. By further optimization of=
the screen-printed front side metallization, the world's first 21% efficie=
nt industrial size 156mm x 156mm p-type Cz-Si solar cell was manufactured a=
t SCHOTT Solar. Both efficiency values are independently confirmed by ISE C=
alLab in September 2012.
"These results, achieved by simple process sequences developed by our exper=
ienced team, impressively demonstrate the potential to reach more than 21% =
cell efficiency using cost effective next generation manufacturing technolo=
gies," Dr. Axel Metz, Director of Solar Cell Development at SCHOTT Solar st=
ates. "Moreover, all steps are available in multiple process options as sho=
wn by our cells with electroplated NiCu front contacts reaching top efficie=
ncies of 20.9%. This offers great flexibility for the implementation in ind=
ustrial mass production," he adds.
Dr. Christian Buchner, Vice President of SCHMID's cell business unit, point=
s out that the cell concept is based on industry established technology and=
reaches the same efficiency potential as other technologies like, for exam=
ple HJT but with lower conversion costs.
Key features of the new record cells
Commercially available 156 mm x 156 mm p-type Czochralski wafers
Industrial dielectric rear side passivation technology
Improved emitter technology
Optimised front side metallization
PERC (Passivated Emitter and Rear Contact) is a technique on backside passi=
vation of crystalline silicon solar cells that SCHOTT Solar has further dev=
eloped for use in industrial mass production and recently licensed to the S=
CHMID Group. Improvement of the backside alone can already increase efficie=
ncy by a full percentage point. The technique can be applied to various typ=
es of wafer materials like monocrystalline and polycrystalline, and also qu=
asimono. It can also be combined with high-efficiency technologies for the =
front sides of cells to open up even greater potential for further increase=
s in efficiency. These also include the selective emitter technology and ad=
vanced metallization techniques offered by the SCHMID Group for complete PE=
RC cell production lines as well as multi busbar module production.
Great news, would be greater if it's really cost effective to get into
PGP key ID: 0x92CCE1EA
Thank you Lu Wei.
Since Schmid is using an APCVD for the coating of dielectric layer on the r=
ear, it is the most cost competitive way to implement PERC technology in ma=
ss production. Also savings of silver by replacing it with Nickel and Coppe=
r will minimize production costs.
Overall it is a very competitive high efficiency cell, which will cost wise=
much more competitive than eg SunPowers IBC.
I'd rather be more prudent. As an established business, Sunpower could
provide panel of 20% efficiency with cell of about 22%, which mean's
it's a mass production result; while SCHOTT Solar and SCHMID Group's
result can only be regarded as the highest "reached" R&D level, where
considerable time and efforts and reduction due to mass population lie
And yes, even cut 0.6% to that result as a mass production prediction
according to my experience, it is still very promising. Two highlights -
APCVD grown Al2O3 and electroplated NiCu front contacts play the key
role. I will see whether I can contact them to do some demo.
PGP key ID: 0x92CCE1EA