?a???p???t???? ?

1
?a???p???t???? ?µ??????e?? epa??stas? sta
f?t?ß??ta????ept?? ?µe????

• T???O??? ?????
• 8? ???????
• ?pe????? ?a????t??a?. ??µ?t?a ?apad?µ?t????

2
??a??a?t???? µ??f?? e????e?a?

• ??????? e????e?a
• Ge??e?µ??? e????e?a
• ???µa?a
• ???a?? e????e?a
• ???s? f?t?ß??ta????

3
?? ???eta? st?? ?????

• 61011 kg H2?He
• ???e sec!!!
• ?p??e?a µ??a??4103 ?g d??ad? 41020 j
• ??tas? t?? a?t???ß???a? st? µ?s? ap?stas?
  ???-?????1353 W/m2
• ?????e?a f?t????? ?????0.5-5 eV (0.2-3 µm)

4
?st????? a?ad??µ?

• 1839 Alexander-Edmond Becquerel- f?t???e?t????
  fa???µe??
• 1954Chapin, Fuller, Pearson d??d?? epaf?? Si
• TFSCsCu2S/CdS/n10
• 1980?µ???a aSi-H
• GaAs/InP
• CdTe
• ?????e? ?a???p???t??

5
? ?ata??µ? t?? PV ??????
6
?µ?a?????-epaf? p/n

• ??e?t???? a?t?stas?10-2-109 O
• ??e??e?a?? ??sµa
• 0-4 eV
• S??te?est?? ap????f?s??
• a (cm-1)
• ??tas? ?e?µat?? f?t?????
• I? (x)I??e-ax

7
(No Transcript)
8
?????aµµa n-Eg

• Te???t???? s??te?est?? ap?d?s?? 85
• ??a?t??? 15-20
• 2002single c-Si n 24.7
• (?e???t??? t?µ? 30)

9
F?t?ß??ta??? fa???µe?? ?a? ?e?t?????a f?t????????

• f?t??e?µa IL
• IFIs (exp(eV/kT)-1)
• IIL IF
• R0?V0?IISCIL
• R8?I0
• IIL IS(exp(eVOC/kT)-1)
• VOCVtln(1IL/Is)
• VtkT/e

10
?a?a?t???st??? I-V f?t???????? epaf?? p-n

• S??te?est?? ap?d?s?? n
• Max t?µ?
• nPm/Pin 100?
• n ImVm/Pin 100
• S??te?est?? p????s?? ff
• ImVm/IscVoc

11
??µ? CIGS ?te?????????

• ?p?st??µa
• ?? (p?s? epaf?)
• Ap????f?t?? CIGS
• (?µ???? p- t?p??)
• ?µ???? n-t?p?? ?etaßat??? st??s? CdS
• ?a?????? ZnO/???
• ?µp??s??a epaf? (grid)

12
?a???p???te? ?? ap????f?t??
13
?d??t?te?

• ?µ???????
• ?a?a???? f????? ???t? st?? ep?f??e?a
• S?ed?asµ?? ? p???? ?a? doping t?? ap????f?t?
• ?d?a??p???s? (passivation) ep?f??e?a?

• ?te????????
• ?a?a???? f????? ???t? st?? epaf? p-n
• ?etat?p?s? ????? (band offset)
• ????????
• ?pa?as??des? f????? st? d?ep?f??e?a
• ???µ?? epa?as??des??
• Rnp/t(np) ? max ??a np
• A??G???? ???S???F? ?????F?????S? ?etat??p? t??
  ep?f??e?a? t?? ap????f?t? (t?p?? p-) se t?p?? n-

14
??a??st?p???s? epa?as??des?? f????? st?
d?ep?f??e?a ??a t?? CIGS ete???????e?

• ?s?µµet?? doping-a?ast??f? d?ep?f??e?a? ?
• n pa??????/p ap????f?t??
• ?at?????? f??t?? d?ep?f??e?a? Q0 ? ????s? ??µ???
  ????? ap????f?t? ?
• ????s? a?ast??f?? d?ep?f??e?a?
• ?p?ped? Fermi ???t? st? ???? a????µ?t?ta?
• ???t?st?? s??d?asµ?? ????? a????µ?t?ta? st?
  d?ep?f??e?a/ap?f??? µe??s?? f???µat??
  epa?as??des?? ?b
• Spikes ??cgt0 (??clt0.3) ? ?????? ??? ???S???F?
• Cliffs ??clt0
• ????s? t?? Eg t?? ap????f?t?-µetat?p?s? ?????
  s??????
• ?p?st??s? e??se?? t?p?? CuGa3Se5 ? CuGa5Se8
  (Ordered-Vacancy Compounds, OVCs)
• ????s? s?????t??s?? ?e???
• Doping ep?f??e?a? ap????f?t???µ?epaf?

15
??a??st?p???s? epa?as??des?? f????? st?
d?ep?f??e?a ??a t?? CIGS ete???????e?
16
S??te?est?? ap?d?s?? CIGS Scs
3 1st World Conference of Photovoltaic Solar
Energy Conversion, Hawaii, 1994, pp. 68754
Prog. Photovolt. Res. Appl. 7 (1999) 311316.5
Solar Energy Mat. Solar Cells 67 (2001)
159166.6 Solar Energy Conference and
Exhibition, Barcelona, 1997, pp. 12501253.
17
????????s? CIGS ???e??? µ????? ?g

• ZnO/CdS/CuInSe2
• a 3-6 105 cm-1
• ??ast??f? d?ep?f??e?a?
• ???s???? Ga ? Cu(In,Ga)Se2
• ?g1.2 eV (30 Ga)
• ????st? n 19.2
• ??s????a ?at????s?? e?d??µes??
  st??s??-µetat?p?s? ?????
• CuInSe2/ZnO
• Cu(In,Ga)Se2/ZnO (cliff st? ZnO)
• Prog. Photovolt Res. Appl. 11 (2003) 225230

18
????????s? CIGS ???e??? µe????? ?g

• Zn?/CdS/CuInS2 ? CuGaSe2
• H µetat?p?s? ????? (band-offset) de? e???e?
  a?ast??f? d?ep?f??e?a?
• Cliff?µe??s? f???µat?? epa?as??des?? ?b
• Voc(0 K) ?b/q
• Cu(In,Ga)S2
• q?Voc??g
• a? ?ggt1.6 eV
• CuInS2/ZnO
• n 6
• ????? e?d??µes? st??s? (buffer-layer free)

19
n-t?p?? a????µ?t?ta st? Ge-doped CuGaSe2

• ?te???????e? CuGaSe2 ?n9.7 (µ??????sta?????)
  n9.3 (?ept? ?µ????)
• ??s????a n-doping
• ??a?t?a?t?st??µ?s? (self compensation)
  p?e?µat??? ?e?? VCu
• ??s?
• ?µf?te?s? ???t?? (ion implantation) Ge ? Zn

20
??ad??as?a eµf?te?s?? ???t??

• 1.A??pt??? µ??????st????? CuGaSe2
• CVT
• ????a???? ap?d??t?? VCu
• 2.Te?µ??? a??pt?s? (Thermal annealing)
• µe??s? s?????t??s?? ap?de?t?? (1018 ?1015 cm-3)
• 3.?µf?te?s? ???t?? Ge
• 4. Te?µ??? a??pt?s? (Thermal annealing) pa???s?a
  Zn
• ZnCu
• Ge d?te?
• n t?p?? a????µ?t?ta
• S?????t??s? d?t??gt 1015 cm-3

21
S?µpe?asµat???

• co-doping µe Ge/Zn ? n-t?p?? CuGaSe2 (?g1.7 eV,
  300 K)
• ??µ??????a ?µ????e??? CuGaSe2
• ?p?µ?????s? e?d??µes?? st??s??
• ?e??s? epa?as??des?? f????? d?ep?f??e?a? st??
  ete???????e?
• ?e?t??s? ap?d?s?? CIGS µe????? ?g
• ?a?? ???s? t?? d?µ?? t?? ??????
• ??e???? ?????? ?at? t? pa?as?e??

22
??ß?????af?a

• K. L. Chopra, P. D. Paulson, V. Dutta, Thin-Film
  Solar Cells An Overview, Prog. Photovolt Res.
  Appl. 12 (2004) 6992.
• A. Goetzberg, C. Hebling, H.-W. Schock,
  Photovoltaic materials, history, status and
  outlook, Materials Science and Engineering R 40
  (2003) 146.
• R. Klenk, Characterisation and modelling of
  chalcopyrite solar cells, Thin Solid Films 387
  (2001) 135-140.
• S.Siebentritt, Wide gap chalcopyrites material
  properties an solar cells, Thin Solid Films
  403404 (2002) 18.
• J. H. Schön, J. Oestereich, O. Schenker, H.
  Raji-Nejad, M. Klenk, n- type conduction in
  Ge-doped CuGaSe2, Appl. Phys. Lett. 75 (19)
  (1999) 2969-2971.
• C. Xue, PhD Thesis, NTUA, Athens 2003.