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Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik Levon Altunyan Fakult¨ at f¨ ur Ingenieurwissenschaften Nanostrukturtechnik Universit¨ at Duisburg-Essen

February 01, 2012

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Outline 1

2

3

4

5

Introduction Problem Description Experiments and Results Dynamic light scattering Profilometry “Safe” regions determination Reference Cell I-V Measurements Type I Cells Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations Type II Cells Conductivity Measurements Summary Conclusions Future Work

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Problem Description

BSF for Photovoltaic Cells Motivation: Classical solutions - negative impact on cells: Different expansion coefficients of Al and Si. Warping of the cell is observed.

Difficulties in subsequent production.

Increased probability of breakage.

New materials such as Si-nanoparticles investigated: A non-toxic material.

Abundant in the nature.

Strongly reduced size.

Suggested Solution: Spin-coated Si-nanoparticles.

Sintered with the Silicon layer.

Controlled, brief, local heating.

Create highly doped p + -type region.

Benefit in cost per watt reduction.

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Dynamic light scattering Profilometry “Safe” regions determination Reference Cell I-V Measurements

Liquids of Si-nanoparticles: HWR. p-doped (boron).

DLS - diameter µ ≈ 100 d.nm; σ ≈ 9 d.nm.

5%wt; 10%wt; Ball milling procedure:

Mean Number [%]

30

1

Pre-dispersing - YTZ beads (300 µm).

2

15 min. ultrasonic cleaning applied.

3

Main-dispersing - YTZ beads (100 µm).

4

Filtered particles Measurement 3 weeks before rest of curves 45 min 2000 rpm 75 min 3000 rpm

20

10

0 10

100

1000

Size [d.nm]

Final filtering - pore size 0, 5µm.

Conclusions: Si-nanoparticles keep size characteristics after three weeks have passed.

Milling for 75 min and reaching 3000 rpm (final mixing velocity) - sufficient.

Graph fit - gaussian distribution, mean value µ ≈ 100d.nm., standard deviation σ ≈ 9d.nm.

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Dynamic light scattering Profilometry “Safe” regions determination Reference Cell I-V Measurements

Layer Thickness

Si-nanoparticles spun on glass substrate: Big glass substrate (25 × 25mm2 ).

Thickness [nm]

An average height of hSiNp = 650nm(±25nm).

Inhomogeneous thickness due to substrate size.

15 1,5 10 1,0 0,5 0,0 0,0

Peak in middle due to deposition method/speed.

Levon Altunyan

953,0 , 874 0 874,0 795,0 716,0 637 0 637,0 558,0 479,0 400,0

2,0 ,

y-Posiition [cm m]

Across sample seven more or less parallel scratch lines (A to G) considered.

0,5

1,0

1,5

2,0

x-Position P iti [[cm]] 2

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Dynamic light scattering Profilometry “Safe” regions determination Reference Cell I-V Measurements

“Safe” regions determination

45

Lasser Inte ensity [[%]

40 35 30 25

"Eye" Eye Guideline Optimal Intensity Optimal p Intensity y Argon g Optimal Intensity Nitrogen

20 15

0

2000

4000

6000

8000

Scan Velocity [mm/min]

0 1 2 3 4 5

-

10000 7

no visible laser illumination; visible laser illumination/no change of the sample’s surface; optimal = change to silver like color of the sample’s surface; slightly scratched layer; ablation of cell’s layer; layer is totally removed;

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Dynamic light scattering Profilometry “Safe” regions determination Reference Cell I-V Measurements

Reference cell - a semi-ready cell with antireflex coating (SiN), front Ag silver grid contacts and back Al layer metalization from the company Solland Solar.

Breakdown voltage can be extracted to be Vbr = −8, 5V .

Open circuit voltage is Voc = 0, 59V .

Short circuit current equals to Isc = −27, 78mA. Power at maximum power point is given as PMPP = 9, 7mW .

Fill factor of FF = 59, 21% can be computed.

An effective cell efficiency of η = 12, 93% was obtained.

Reference Cell by Solland Solar with Anti-Reflective Coating and Metal Contacts 0,10

0,12

Dark

Illuminated Dark

0,10 0,08

Current [A]

0,05

Current [A]

Reference Cell with Anti-reflex Coating and Al BSF; No Si-nano Particles, No Sintering;

0,00

-0,05

0,06

Rs = 5,9 Ω; Rsh = 2060,19 Ω;

0,04 0,02 0,00 -0,02

-0,10 -5

0

5

10

15

-0,04

-3

Voltage [V]

Levon Altunyan

-2

-1

0

1

Voltage [V]

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Sample Name Reference #0110 #11 #05 #08 #17 #0622062011 #13 #07 #06 20.06.11

Levon Altunyan

In Figure a1 a2 a3 a4 a5 a6 a7 a8 a9 a10

Dynamic light scattering Profilometry “Safe” regions determination Reference Cell I-V Measurements

Scan Parameters No Laser Treatment 1x10%100mm/min 1x10%100mm/min 1x15%100mm/min 1x17%100mm/min 1x17%100mm/min 1x18%100mm/min 1x18%100mm/min 1x19%100mm/min 6(continuous ↓↑)x50%10m/min 1x30%100mm/min

Nano Particles No Yes Yes Yes Yes Yes Yes Yes Yes No

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

Fill Factor vs Laser Intensity

Cell Efficiency vs Laser Intensity 7

a3

a4

a4

6

40

a3

a7 5

a10

a7 a6 a7

30

a8

4

η [%]

FF [%]

35

a9 a9

3 a8

2

25

a5

a1 1

a7

a2

20 0

5

10

15

a1

0

a5 20

25

30

0

5

10

a9

a5

15

a10 20

25

30

Laser Intensity [%]

Laser Intensity [%]

Levon Altunyan

a2

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

Sample #05 from 22.06.2011 1xscan 15% @ 100mm/min Dark Illuminated

0,04

Current [A]

0,02

Rs = 9,75 Ω; Rsh = 689,54 Ω;

0,00

-0,02

-0,04

-0,9

-0,6

-0,3

0,0

0,3

0,6

0,9

Voltage [V]

Solar Cell With Anti-reflective Coating and Ag Front Contacts Grid, Deposited Si-nanoparticles.

Iscan = 15% Vscan = 0, 1m/min.

Fill Factor FF ≈ 41%.

Cell efficiency η = 6, 38%.

Low series resistance Rs = 9, 75Ω.

Levon Altunyan High shunt resistance Rsh = 689,Universit¨ 54Ω.at Duisburg-Essen - Fakult¨at f¨ur Ingenieurwissenschaften, Nanostrukturtechnik Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

1

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

grinding of the sample’s edges.

cleaning putting on an adhesive tape on the front side of the sample as protection measure; spin-coating; 2

cleaning the edges with a Cotton Swab rinsed in Ethanol or Acetone;

3

grinding of the sample’s edges;

laser sintering step (Iscan = 15% Vscan = 100mm/min); 4

cleaning the sample’s Si-nanoparticle thin film.

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

Average Fill Factor and Corresponding Efficiency 1

2

3

4

5

6

7

8

9 10 11 12 13 14 15 16 17

1

2

3

4

5

6

7

8

9 10 11 12 13 14 15 16 17

Combination [-]

-0,020

Ιsc[A]

1,5

-0,010

1,0 0,5

0,000

FF [%]

Voc [V]

-0,005

Combination [-]

1

2

3

4

5

6

7

8

9 10 11 12 13 14 15 16 17

2,5 2,0

-0,015

0,55 0,50 0,45 0,40 0,35 0,30 0,25 0,20 0,15 0,10

3,0

η [%]

Average Open Circuit Voltage and Short Circuit Current

0,55 0,50 0,45 0,40 0,35 0,30 0,25 0,20 0,15

0,0

1

2

3

4

5

6

7

8

9 10 11 12 13 14 15 16 17

Combination [-]

Combination [-]

Figure: Applying Different Cleaning Procedures: a.) Open Circuit Voltage and Short Circuit Current; b.) Fill Factor and Corresponding Efficiency;

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Combination 1 2 3 4 5 6 7 8

Levon Altunyan

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

Included Optional Steps Grinded (Step 01) and Sintered Samples, No Particles Deposited Cleaning the Edges With a Cotton Swab Rinsed in Acetone (Step 02) Cleaning the Edges With a Cotton Swab Rinsed in Ethanol (Step 02) Reference Cell, Grinded Only (Step 01), No Particles Deposited, Not Sintered Grinding of the Samples’ Edges, (Step 03) Grinding of the Samples’ Edges, (Step 01) Cleaning with Acetone the Samples’ Nanoparticle Thin Film, (Step 04) Cleaning with Ethanol the Samples’ Nanoparticle Thin Film, (Step 04)

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

Combination [-]

Combination [-] 5

1 6

7

8

0,6 0,5 0,4 0,3 0,2 0,1 0,0

5

6

7

8

2,5

1,0 0,5 0,0

26

-0,015

22

0,000

4

1,5

24

-0,005

3

2,0

-0,020

-0,010

2

[%]

4

η

3

Voc [V]

2

FF [%]

2

Jsc [A/cm ]

1

20 18 16

1

2

3

4

5

6

7

8

1

2

Combination [-]

3

4

5

6

7

8

Combination [-]

Figure: Applying Different Cleaning Procedures: a.) Open Circuit Voltage and Short Circuit Current; b.) Fill Factor and Corresponding Efficiency;

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

Q-tip (Acetton) Sample #05 0,06 Illuminated(1) Dark(1) Illuminated(2) Dark(2) Illuminated(3) Dark(3)

0,04

Current [A]

0,02 0,00 -0,02 -0,04 -0,06

-3

-2

-1

0

1

2

3

Voltage [V]

Q-tip (Acetton) Sample #06 0,005 0,000 -0,005

Current [A]

-0,010 -0,015 -0,020 Illuminated (1) Dark(1) Illuminated(2) Dark(2) Illuminated(3) Dark(3)

-0,025 -0,030 -0,035 -0,040 -3

-2

-1

0

1

2

3

Voltage [V]

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

Sample 20110901 ‐ 08 10 µm

10 µm

10 µm

Scan unbehandelt Scan unbehandelt – hochreflektierend – unbehandelt

100 µm

Figure: Micrograph Sintered Coated Sample, Transition (Untreated-Treated-Untreated) Region

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

10 µm

Highly reflective

Non-reflective

Difference in color!

Figure: Highly vs. Low Reflective Area Comparison; Semi-ready Solar Cell with Anti-reflex Coating and Pre-deposited Front Side Ag Contacts (Sample No 10, 01.09.2011: 6× preheating, Ipreheat = 50%@Vpreheat = 10m/min; 1 sinter scan, Isintern = 30%@Vsintern = 0, 2m/min)

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

Figure: Back Surface of the Solar Cells After Sintering: a.) Type II 21.09.2011; b.) Type I, R foils 01.06.2011; c.) Kapton

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Diffusion Coefficient of Silver in Silicon vs Temperature

2

Diffusion Coefficient [μm /s]

10

Primary Observations Final IV-Characterizations Crystallinity and Cell Behavior SEM Investigations EDX Considerations

1 1 µm

0,1

-3

2

2*10 *exp{-1,59/(κb*T)}*10 μm /s

[45, 46]

2*10 *exp{-1,6/(κb*T)}*10 μm /s

[47]

0,01 800

-8

[43, 44]

-3

-8

-5

-8

2

6*10 *exp{-1,15/(κb*T)}*10 μm /s Extrapolation of

1000

1200

Temperature [°C]

O

2

C

N Ti

graph

1400 Ag

Si

Zn

Figure: Possible diffusion of front silver contacts into the n-layer takes place. More importantly, there exists a probability that the front contacts get even further - to the p-layer.

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Conductivity Measurements

15% 1scan with Si-nano Particles

0,12

0,12

Dark Illuminated

0,10

35% 1scan with Si-nano Particles Dark Illuminated

0,10 0,08

0,08

Current [A]

Current [A]

0,06 0,06 0,04 0,02

Rs = 18,88 Ω; Rsh = 1204,54 Ω;

0,04

Rs = 23,38 Ω; Rsh = 76,21 Ω;

0,02 0,00 -0,02

0,00

-0,04

-0,02

-0,06 -0,04

-3

-2

-1

0

1

-3

2

-2

Voltage [V]

0

1

2

Efficiency vs Laser Intensity

On-Off Current Ratio - Samples With and Without Nanoparticles With Particles - Initial Study from 13.09.2011 With Particles - Samples from 16.09.2011 Without Particles - Samples from 16.09.2011

100

-1

Voltage [V]

3,0 2,5

Efficiency [%]

Ratio [+1/-1]

10

1

2,0 1,5 1,0

0,1 0,5 0,01

15

20

25

30

35

40

45

0,0

0

10

Levon Altunyan

20

30

40

50

60

70

Laser Intensity [%]

Laser Intensity [%]

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Conductivity Measurements

10

-2

10

-3

10

-4

Conductivity Total vs Laser Intensity

−1

−1

Conductivity [Ω cm ]

Introduction Experiments and Results Type I Cells Type II Cells Summary

25

30

35

40

45

50

55

Laser Intensity [%] Conductivity of samples treated in Ar, N2, 6

10

without laser treatment with Si-NP spincoated only

Comparisson: Al (data from Handbook of

0

th

Chemistry and Physics 90 ed.)

-1

-1

Conductivity [Ω cm ]

10 5 5x10

U

RL

RL

RL

RL

RL

RL Rtotal

U

Si-NP

RSi-NP Si Wafer RL

RWafer

dSiNp

10

-1

10

-2

10

-3

dwafer

Argon

Levon Altunyan

N2

Si

Si+Np (no laser)

Al

Parameters

RL

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Conductivity Measurements

Dielectric Constant, Results and Discussion

Results: S ) corresponds well to the values given in Conductivity values (σtotal ≤ 2, 57 × 10−3 cm literature [2].

Comparable with nanoparticle-coated Si-wafer pieces not treated with an IR-laser S (σNoLaser ≤ 3, 52 × 10−3 cm ).

S .

Conductivity of the Si-wafer itself σwafer = 0, 0137 cm

Single scans with low intensities are not sufficient for melting most of the deposited Si-nanoparticles.

Remove native silicon surface oxide (Eg = 9eV [2]) with hydrofluoric acid before laser treatment.

Use more scans at higher intensity.

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Conclusions Future Work

Summary

Summary The size and stability of the particles inside the dispersion was determined.

Laser treated semi-ready structures from Solland Solar with (Type I) and without antireflective coating (Type II).

The characteristic curves of different treated samples are examined.

Fill Factor of FF = 41%; cell efficiency of around η = 6, 38% (Type I).

Fill Factor of FF = 27%; cell efficiency of around η = 2, 95% (Type II).

SEM measurements are carried out.

Estimation of doping depth to at least hBSF = 5µm is achieved.

Breakdown voltage and breakdown field strength are studied.

R foils.

An initial work with thin-film Kapton

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

Introduction Experiments and Results Type I Cells Type II Cells Summary

Conclusions Future Work

Proposals for Future Work More thorough studies of the regions characterized by a highly reflective surface.

Further studies of the correlation between crystallinity size and diode behavior.

R foils.

Pulsed UV-Laser treatment on Kapton

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

References Abbreviations

N. Benson NETZ Vollversammlung, Conference at University Duisburg-Essen, 2011 K. Lamine Realisierung funktionaler Si-D¨ unnfilme durch Laserkristalisation von nanopartikul¨ arem Silizium.

Bachelor Thesis, 2012

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

References Abbreviations

Levon Altunyan

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik

References Abbreviations

Ag Al B BSF EDX η FF HWR Isc O P Pmpp Rs Rsh SEM Si Voc Zn

Levon Altunyan

silver aluminum boron back surface field energy-dispersive x-ray solar cell efficiency fill factor hot wall reactor short circuit current oxygen phosphorus power at maximum power point equivallent parasitic series resistance equivallent parasitic parallel resistance scanning electron microscope silicon open circuit voltage zinc :

Universit¨ at Duisburg-Essen - Fakult¨ at f¨ ur Ingenieurwissenschaften, Nanostrukturtechnik

Evaluation von Laser-bearbeiteten Si-nanopartikeld¨ unnfilmen f¨ ur den Einsatz in der Photovoltaik