Nanocrystalline silicon emitter optimization for Si-HJ solar cells: Substrate selectivity and CO2 plasma treatment effect

被引：52

作者：

Mazzarella, Luana ^{[1
]}

Kirner, Simon ^{[1
]}

Gabriel, Onno ^{[1
]}

Schmidt, Sebastian S. ^{[1
]}

Korte, Lars ^{[2
]}

Stannowski, Bernd ^{[1
]}

Rech, Bernd ^{[2
]}

Schlatmann, Rutger ^{[1
]}

机构：

[1] Helmholtz Zentrum Berlin Mat & Energie, PVcomB, Schwarzschildstr 3, D-12489 Berlin, Germany

[2] Helmholtz Zentrum Berlin Mat & Energie, Inst Silicon Photovolta, Kekulestr 5, D-12489 Berlin, Germany

来源：

PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE | 2017年 / 214卷 / 02期

关键词：

heterojunctions; hydrogenation; nanocrystalline materials; plasma treatment; silicon; solar cells; CHEMICAL-VAPOR-DEPOSITION; OXIDE BUFFER LAYER; MICROCRYSTALLINE SILICON; SURFACE-MORPHOLOGY; GROWTH; NUCLEATION; FILMS; DEPENDENCE; EFFICIENCY; INTERFACE;

D O I：

10.1002/pssa.201532958

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We investigated hydrogenated nanocrystalline silicon (nc-Si:H) films as doped emitter layers for silicon heterojunction solar cells. Firstly, we focused on the effect of the nc-Si:H deposition conditions and film growth on the intrinsic hydrogenated amorphous silicon passivation layer ((i)a-Si:H) underneath. Three different p-doped emitters were compared: nc-Si:H, nc-SiOx:H, and a-Si:H. We found that the nc-Si:H and nc-SiOx:H growth enhances the passivation of the epitaxy-free (i)a-Si:H layer, yielding implied open circuit voltages above 730mV. Secondly, for (p)nc-Si:H emitters, we observed a trade-off between fill factor (FF) and open circuit voltage (V-oc) by using two types of (i)a-Si:H films. A slight epitaxy of the (i)layer seems to promote the rapid nucleation of nc-Si:H, thereby positively affecting the FF (79.5%) and series resistance but reducing V-oc (670mV). Contrarily, on well-passivating (i)a-Si:H the nc-Si:H nucleation is more difficult resulting in S-shaped I-V curves, presumably due to low built-in voltage and a poor emitter/TCO contact. To circumvent this dilemma, a CO2 plasma treatment is used to oxidize the a-Si:H surface before the nc-Si:H emitter deposition thereby enhancing nucleation. Accordingly, a FF of 74.5% with V-oc of 727mV is reached in the best device, yielding a conversion efficiency of 21%. HR-TEM micrograph of the front layer stack of the solar cell. The image shows a region close to the valley between two pyramids. From bottom to top: c-Si substrate, (i)a-Si:H passivation layer showing epitaxially grown regions, (p)nc-Si:H emitter layer, and In2O3:Sn (ITO). Yellow lines highlight layers and individual crystals. Silicon zone axis orientation is < 101 >.

引用

页数：7

共 42 条

[1] Bailly M, 2014, 2014 IEEE 40TH PHOTOVOLTAIC SPECIALIST CONFERENCE (PVSC), P1201, DOI 10.1109/PVSC.2014.6925130
[2] Silicon oxide buffer layer at the p-i interface in amorphous and microcrystalline silicon solar cells
Bugnon, Gregory
Parascandolo, Gaetano
Haenni, Simon
Stuckelberger, Michael
Charriere, Mathieu
Despeisse, Matthieu
Meillaud, Fanny
Ballif, Christophe
[J]. SOLAR ENERGY MATERIALS AND SOLAR CELLS, 2014, 120 : 143 - 150
[3] SUBSTRATE SELECTIVITY IN THE FORMATION OF MICROCRYSTALLINE SILICON - MECHANISMS AND TECHNOLOGICAL CONSEQUENCES
CABARROCAS, PRI
LAYADI, N
HEITZ, T
DREVILLON, B
SOLOMON, I
[J]. APPLIED PHYSICS LETTERS, 1995, 66 (26) : 3609 - 3611
[4] Mixed-phase p-type silicon oxide containing silicon nanocrystals and its role in thin-film silicon solar cells
Cuony, P.
Marending, M.
Alexander, D. T. L.
Boccard, M.
Bugnon, G.
Despeisse, M.
Ballif, C.
[J]. APPLIED PHYSICS LETTERS, 2010, 97 (21)
[5] Surface passivation properties of boron-doped plasma-enhanced chemical vapor deposited hydrogenated amorphous silicon films on p-type crystalline Si substrates -: art. no. 022104
De Wolf, S
Beaucarne, G
[J]. APPLIED PHYSICS LETTERS, 2006, 88 (02) : 1 - 3
[6] Abruptness of a-Si:H/c-Si interface revealed by carrier lifetime measurements
De Wolf, Stefaan
Kondo, Michio
[J]. APPLIED PHYSICS LETTERS, 2007, 90 (04)
[7] Boron-doped a-Si:H/c-Si interface passivation:: Degradation mechanism
De Wolf, Stefaan
Kondo, Michio
[J]. APPLIED PHYSICS LETTERS, 2007, 91 (11)
[8] Improved amorphous/crystalline silicon interface passivation by hydrogen plasma treatment
Descoeudres, A.
Barraud, L.
De Wolf, Stefaan
Strahm, B.
Lachenal, D.
Guerin, C.
Holman, Z. C.
Zicarelli, F.
Demaurex, B.
Seif, J.
Holovsky, J.
Ballif, C.
[J]. APPLIED PHYSICS LETTERS, 2011, 99 (12)
[9] Impact of doped microcrystalline silicon oxide layers on crystalline silicon surface passivation
Ding, K.
Aeberhard, U.
Lambertz, A.
Smirnov, V.
Hollaender, B.
Finger, F.
Rau, U.
[J]. CANADIAN JOURNAL OF PHYSICS, 2014, 92 (7-8) : 758 - 762
[10] Optimized amorphous silicon oxide buffer layers for silicon heterojunction solar cells with microcrystalline silicon oxide contact layers
Ding, Kaining
Aeberhard, Urs
Finger, Friedhelm
Rau, Uwe
[J]. JOURNAL OF APPLIED PHYSICS, 2013, 113 (13)

← 1 2 3 4 5 →