NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

Contract No. DE-AC36-08GO28308

Performance Characterization 

and Remedy of Experimental 

CuInGaSe2 Mini-Modules

Preprint

F.J. Pern, F. Yan, L. Mansfield, and S. Glynn

National Renewable Energy Laboratory

M. Rekow and R. Murison

ESI-PyroPhotonics Lasers, Inc.

Presented at the 37th IEEE Photovoltaic Specialists Conference 

(PVSC 37)

Seattle, Washington

June 19-24, 2011

Conference Paper

NREL/CP-5200-51812

July 2011
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1

PERFORMANCE CHARACTERIZATION AND REMEDY OF EXPERIMENTAL

CuInGaSe2 MINI-MODULES

F. J. Pern1, F. Yan1, L. Mansfield1, S. Glynn1, M. Rekow2, and R. Murison2

1 National Center for Photovoltaics, National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, CO 80401, USA 2 ESI-PyroPhotonics Lasers, Inc., 1275 Kesmark, Dollard-des-Ormeaux, QC Canada H9B 3J1

ABSTRACT

We employed current-voltage (I-V), quantum efficiency 

(QE), photoluminescence (PL), electroluminescence (EL), 

lock-in thermography (LIT), and (electrochemical) 

impedance spectroscopy (ECIS) to complementarily 

characterize the performance and remedy for two pairs of 

experimental CuInGaSe2 (CIGS) mini-modules. One pair 

had the three scribe-lines (P1/P2/P3) done by a single 

pulse-programmable laser, and the other had the P2/P3 

lines by mechanical scribe. Localized QE measurements 

for each cell strip on all four mini-modules showed nonuniform distributions that correlated well with the presence 

of performance-degrading strips or spots revealed by PL, 

EL, and LIT imaging. Performance of the all-laser-scribed 

mini-modules improved significantly by adding a thicker Aldoped ZnO layer and reworking the P3 line. The efficiency 

on one of the all-laser-scribed mini-modules increased

notably from 7.80% to 8.56% after the performancedegrading spots on the side regions along the cell array 

were isolated by manual scribes.

INTRODUCTION

One of the advantages in thin-film PV technologies is the 

use of monolithic integration for fabricating modules; these 

modules’ performance can be affected by the quality of 

absorber, cell components, and scribe lines. The 

conventional scribing process for monolithically integrated 

CIGS modules in production lines typically uses a laser for 

Mo removal (P1) followed by mechanical stylus for P2 and 

P3 scribes [1–5]. As it is well known, mechanical scribing 

can cause potential tearing of coated layers and a zig-zag 

feature of the scribe lines; additionally, the line-to-line 

spacing can not be very narrow. Therefore, all-laser

scribing for the three scribe lines is highly attractive. 

Extensive studies on laser scribing for component layers 

of thin-film solar cells using different wavelength and pulse 

laser systems were conducted previously by Compaan 

and coworkers [6,7]. In practice, use of a single laser and 

single wavelength will greatly simplify the processing. To 

address these issues, the collaboration between NREL 

and PyroPhotonics has investigated and reported for the 

first time the use of a single pulse-programmable laser 

with a single wavelength (1064 nm) to achieve successful 

scribing of all three P1, P2, and P3 lines [8-10]. The 

technical details were described in ref. [10]. Good-quality 

scribe lines were demonstrated on CIGS mini-modules 

made on soda lime glass substrates [8]. Previously, we 

also demonstrated that the electrical performance of the 

pair of all-laser-scribed mini-modules could be remedied 

(improved) by P3 rework, after the thickness of the Aldoped ZnO (AZO) window layer was increased from an 

initial 0.12 μm to 0.50 μm to decrease the sheet resistance. 

The results were comparable with a pair of P2/P3 

mechanically scribed mini-modules with an initial 0.50 μm 

AZO [9,10]. However, due to time constraint, the four minimodules were not thoroughly characterized prior to those 

reports given in ref. [8-10]. This paper describes our 

continued efforts at NREL to seek and employ useful 

characterization methods to better understand and identify 

the performance-limiting factors as well as to evaluate and 

implement simple remedy methods to mitigate those 

factors to improve performance. As detailed below, the 

results indicate that PL, EL, LIT, and localized QE 

measurements are highly complementary in identifying the 

degrading spots or regions that directly affect the 

performance of individual cell strip on the mini-modules, 

and that simple manual scribes can be used to isolate off 

those spots or regions, resulting in significant 

improvements in efficiency. ECIS analysis renders further 

understanding of the electrical characteristics of the minimodules before and after remedy. This paper presents a 

summary of results from recent work combined with some 

of previous studies.

EXPERIMENTAL

Details of the collaborated work to fabricate the minimodules and their performance prior to recent work were 

described previously in ref. [8-10]. The mini-modules were 

characterized by I-V measurements for the entire working 

area using an Optical Radiation Corp.’s Solar Simulator 

1000. Localized QE on each cell strip was measured with 

a custom-built QE system using a small, narrow probing 

light beam. Using also a custom-built system for PL (and 

EL) imaging, 810 nm laser diodes were used as the 

excitation source at a condition close to one-sun intensity, 

with RG1000 Schott glass filters mounted on the camera 

lens to sufficiently attenuate the reflected laser light. The 

PL signal was collected by a cooled silicon chargecoupled device (CCD) camera. The EL imaging was 

conducted on the same setup by driving forward-bias 

current through the test cells. In this case, the long-pass 

filters on the camera were removed. Illuminated lock-in 

thermography (LIT) was also employed initially but was

not available in later stage due to maintenance repair. To 

test the possibility and effectiveness of remedy processing, 

either the 1064-nm laser or a sharp diamond-tipped scribe 

was used to remove or isolate the “defective” spots or 
2

regions, as identified by PL and EL (and LIT), on the two 

all-laser-scribed mini-modules. The mini-modules’ 

performance was then re-measured, followed by PL and 

EL imaging. The mini-modules were also examined in the 

dark with an ECIS system comprised of an SI 1260 

impedance/gain-phase analyzer and an SI 1286 

electrochemical interface from Schlumberger 

Technologies operated with ZPlot and ZView software 

from Scribner Associates.

RESULTS AND DISCUSSION

Characterization by PL, EL, and LIT imaging

Figure 1 shows the room-light, PL, EL, and LIT images for 

the all-laser-scribed mini-module C2681 at its initial stage 

with 0.12 μm AZO. The room-light image in Fig. 1(a) 

shows apparently (visibly) uniform appearance over the 

entire mini-module except for a visible white spot close to

the left edge of the cell strip #9 (as marked in Fig. 1(a) 

from top down). However, this white spot, likely produced 

by the “spitting” during CIGS film deposition, caused a 

large black area on the PL image in Fig. 1(b), produced a 

large white spot in LIT (Fig. 1(d)), and rendered the entire 

cell strip EL-inactive, as seen in Fig. 1 (c). In addition, PL, 

EL and LIT imaging revealed many more recombinationactive spots as seen in Fig. 1 (b-d). These recombinationactive spots, large or small, were also observed on three 

other mini-modules, indicating the presence of inherent 

deficiency in the aged vacuum thermal co-evaporation 

system used for the CIGS film growth.

Performance Remedy

By AZO thickness increase and P3 rework. The two alllaser-scribed mini-modules, C2681 and C2684, with an 

initial 0.12-μm AZO showed poor efficiency at 5.31% and 

4.08% due to high series resistance (Rs = 114 and 128 

ohm-cm2), low shunt resistance (Rsh = 503 and 280 ohmcm2

) and fill factor (FF = 34.3% and 29.6%), respectively. 

Compared with the ~16% efficiency and >90% external 

quantum efficiency (EQE) at 750 nm of small-size (0.42-

cm2

) cells on a control, the poor performance was 

obviously introduced in part by the 0.12-μm AZO layer,

which was insufficient for the 6.5-mm cell width [8]. The 

low Rsh indicates the presence of shunting however,

possibly introduced by scribing. To utilize the high 

precision and repeatability of laser scribing and the low 

extent of damaging along the two sides of the scribed line 

[8] as well as to examine the possibility of remedying the 

poor performance, another layer of 0.38-μm AZO was 

added and the P3 scribe line reworked on both minimodules. The width of the reworked scribe lines remained 

very narrow (compare Fig. 2(a and c) with Fig. 1(b and c)). 

In comparison, the scribe lines made by mechanical 

scribing on two other mini-modules with 0.50-μm AZO 

were substantially wider as revealed by the dark lines in 

PL and EL images (not shown). Additionally, a narrow strip 

on the left side of C2681, where the visible spot was 

located, was also ablated off by the laser, as indicated by 

the white dash line in Fig. 1(a). PL and EL imaging in Fig. 

2(a and c) revealed the changes: the four black dots and 

area seen on cell strips #1, 5, 6, and 9 in Fig. 1(b and c) 

are no longer present. Cell strip #1 became dimmed in PL 

Figure 1 (a) Room-light, (b) PL, (c) EL, and (d) LIT 

images for the all-laser-scribed mini-module,

C2681, with 0.12 μm AZO.

Figure 2 (a, b) PL and (c, d) EL images for the minimodule C2681 P3-reworked with 0.50 μm AZO 

before and after two manual scribes on the right 

side to isolate the regions having numerous black 

dots and a large spot on cell strip #9. A narrow 

strip on the mini-module’s left side was previously 

ablated off with laser as indicated by the dashed 

white line in Fig. 1(a).
3

and EL, as seen in Fig. 2(a and c), however, suggesting a 

shorting problem likely caused by unsatisfactory P3 

rework. Cell strip #9 also remained EL-inactive, indicating 

the presence of “other” performance-degrading area, 

which is clearly identified to be on the right side of the cell 

strip as seen in Fig. 2(a). The performance of P3-reworked 

C2681 and C2684 mini-modules with 0.50-μm AZO were

improved substantially, as reported previously in ref. [8,9] 

and also given in the top half of Table 1 below.

Without further investigation one would attribute the 

efficiency improvement from I-V measurements to the 

reduced sheet resistance from thicker AZO and the 

removal of the recombination spots and regions on the left 

edge. However, results of subsequent localized EQE 

measurements for every individual cell strip (a total of 10) 

on C2681 and C2684 showed that some cell strips had 

improved (e.g., strips #5 and #8) and some became worse 

than before (strips #2 and #10), indicating the potential 

shortcoming of manual P3 rework. The EQE plots in Fig. 3

illustrate the small-to-significant improvement for cell strips 

#5 and #8 on the two all-laser-scribed mini-modules. The 

QE curves also show the spectral changes due to AZO 

thickness increase. The non-uniform changes in QE were 

further confirmed with PL and EL imaging, as given in Fig. 

2 above.

By manual scribes to isolate recombination-active areas. 

In order to test the effectiveness of further performance 

improvement, the right edge with numerous small black 

dots seen in Figs. 1 and 2 was isolated by manually 

scribing twice (sequentially) with a sharp diamond-tipped 

scribe. The two scribes are seen as the two linear black 

lines in the PL and EL images in Fig. 2 (b and d). After 

each scribe, the mini-module C2681 was I-V and QE

measured. The two scribes resulted in further efficiency 

improvements from 7.80% to 8.38% and 8.56%, whereas 

the cell strip #9 now became PL- and EL-active, as seen 

in Fig. 2 (a vs. b) and (c vs. d). The “other” performancedegrading area is seen now located on the right edge of 

the cell strip. However, the cell strip #1 remained inactive 

since the P3 rework as indicated by QE, PL, and EL 

imaging and could not be recovered by the two manual 

scribes; this indicates the presence of a serious shorting 

that has yet to be identified and remedied with more work. 

For the second all-laser-scribed mini-module C2684, 

similar manual scribe was conducted once, resulting in a 

small efficiency improvement (Table 1). No manual scribes 

were performed on the two mechanically-scribed minimodules, C2682 and C2683, because the recombinationactive black spots were located mostly in the central 

regions of the mini-module squares (not shown).

Performance non-uniformity characterized by 

localized QE measurements

Figure 4 compares the EQE values at six wavelengths 

(450, 550, 650, 750, 850, and 950 nm) for the mini-module 

C2681 at its initial condition (top) and at its final state after 

all three isolation treatments (bottom). The performance 

non-uniformity is clearly reflected by the uneven QE 

response of each individual cell strip on the mini-module 

C2681. Similar results are also obtained on three other 

mini-modules. The effect of adding a thicker AZO layer, P3

rework, and two manual scribes is reflected by the 

changes in individual QE response (top vs. bottom). The 

QE responses correlate qualitatively with the PL and EL 

intensity seen in Figs. 1 and 2 for the C2681 at its initial 

state. However, for the mini-module at its final state, as 

0

3

5

8

11

13

16

18

350 450 550 650 750 850 950 1050 1150 1250

Wavelength (nm)

External Quantum Efficiency (%)

C2681-1-Cell5

C2681-2-Cell5

C2681-1-Cell8

C2681-2-Cell8

C2684-1-Cell5

C2684-2-Cell5

C2684-1-Cell8

C2684-2-Cell8

QE Increase on Mini-Modules from 0.12 μm to 0.50 μm AZO 

0.12 μm

0.50 μm

0.50 μm

0.12 μm

Figure 3 External quantum efficiency (EQE) spectra

measured for cell strips #5 and #8 on the two alllaser-scribed mini-modules before and after 

addition of a thicker AZO and P3 rework.

0

2

4

6

8

10

12

14

16

C2681-1-

Cell-1

C2681-1-

Cell-2

C2681-1-

Cell-3

C2681-1-

Cell-4

C2681-1-

Cell-5

C2681-1-

Cell-6

C2681-1-

Cell-7

C2681-1-

Cell-8

C2681-1-

Cell-9

C2681-1-

Cell-10

C2681 Cell Strip

External QE at Middle Center (%)

450 nm 550 nm 650 nm 750 nm 850 nm 950 nm

0

2

4

6

8

10

12

14

16

C2681-4-

Cell-1

C2681-4-

Cell-2

C2681-4-

Cell-3

C2681-4-

Cell-4

C2681-4-

Cell-5

C2681-4-

Cell-6

C2681-4-

Cell-7

C2681-4-

Cell-8

C2681-4-

Cell-9

C2681-4-

Cell-10

C2681 Cell Strip

External QE at Middle Center (%)

450 nm 550 nm 650 nm 750 nm 850 nm 950 nm

0

2

4

6

8

10

12

14

16

C2681-1-

Cell-1

C2681-1-

Cell-2

C2681-1-

Cell-3

C2681-1-

Cell-4

C2681-1-

Cell-5

C2681-1-

Cell-6

C2681-1-

Cell-7

C2681-1-

Cell-8

C2681-1-

Cell-9

C2681-1-

Cell-10

C2681 Cell Strip

External QE at Middle Center (%)

450 nm 550 nm 650 nm 750 nm 850 nm 950 nm

0

2

4

6

8

10

12

14

16

C2681-4-

Cell-1

C2681-4-

Cell-2

C2681-4-

Cell-3

C2681-4-

Cell-4

C2681-4-

Cell-5

C2681-4-

Cell-6

C2681-4-

Cell-7

C2681-4-

Cell-8

C2681-4-

Cell-9

C2681-4-

Cell-10

C2681 Cell Strip

External QE at Middle Center (%)

450 nm 550 nm 650 nm 750 nm 850 nm 950 nm

Figure 4 EQE at six wavelengths for the 10 cell 

strips on C2681 mini-module at its initial condition 

with 0.12 um AZO (top) and at its final state after 

addition of a thicker AZO layer, P3 rework, and two 

manual scribes (bottom). See text for details.
4

shown in Fig. 2 (b and d), the correlation is lost particularly

in the region from cell strip #7 to #10. The revival of cell 

strip #9 upon scribe isolation is evident by the large 

increase in QE response, but the cell strips #7, 8 and 10

show large reductions in QE. While the exact cause is not 

readily determined, it is likely that there is some level of 

QE current leakage on the cell strips introduced by the 

second manual scribe. This reasoning is evident by the 

still EL-active narrow strip between the two manual scribe 

lines seen in Fig. 2(d), which should have become EL 

inactive (dark) if the scribe had completely broken all

electrical connections as the first manual scribe did.

The I-V parameters for the four mini-modules at its initial 

state and after remedy treatments are summarized in 

Table 1 for comparison. The subsequent beneficial effects

of isolating off the performance-degrading areas, i.e., P3 

rework with adding a thicker AZO followed by one or two 

manual scribes, as indicated in the “film/edge reworked” 

column and by the number after the mini-module ID, are 

shown for the two all-laser–scribed mini-modules, C2681 

and C2684. One interesting observation is that, except for 

C2683, the other three mini-modules showed higher 

efficiency after having been stored in a N2-purged drybox 

for nearly eight months and I-V re-measured prior to 

manual scribes, e.g., a 7.7% increase in C2681-2N vs. 

C2681-2, and a 10.2% increase in C2684-2N vs. C2684-2, 

where N stands for new measurement. (It should be noted 

that the light intensity of solar simulator set for the Si 

reference cell was adjusted slightly higher by ~4.5% in 

between.) The corresponding series resistance Rs 

decreased and shunt resistance Rsh increased on both 

all-laser–scribed mini-modules, but the changes in Rs and 

Rsh were reversed on the mechanically scribed pair. The 

reason is not clear, although without any supporting 

evidence, one inclines to suspect there was some sort of 

material settlement during the storage period.

Impedance spectroscopy analysis

(Electrochemical) impedance spectroscopy (IS or ECIS as 

used here) has been applied to characterize various solar 

cells including Si, dye-sensitized, and CIGS solar cells 

[11-17]. The four mini-modules were also characterized by 

ECIS using a 10-mV AC modulation amplitude without 

bias sweeping from 1M Hz to 1 Hz in the dark. No 

measurements were available for the all-laser-scribed 

mini-modules at its initial state with 0.12 μm AZO. Figure 5

shows the complex plane plots (imaginary Z” vs. real Z’)

for the four mini-modules. Essentially, all four CIGS minimodules can be represented by a simple “Rs’ + (Rp // C)”

equivalent circuit, where Rs’ is the series resistance for

contacts and bulk, Rp the recombination/diffusion

resistance, and C the depletion/diffusion capacitance of 

the solar cells in parallel to Rp [11-17]. Diffusion 

resistance and capacitance for CIGS solar cells or miniC2683 C2681 C2684 C2682

0 100 200 300 400 500

-400

-300

-200

-100

0

100

Z'

Z''

Mini-C2681-10mV-Dark1.z

Mini-C2681-3N-10mV-Dark2.z

Mini-C2684-10mV-Dark1.z

Mini-C2684-3N-10mV-Dark2.z

Mini-C2682-10mV-Dark1.z

Mini-C2683-10mV-Dark1.z

Figure 5 Complex plane plots for the four minimodules, ID indicated next to the curves, with or 

without the manual scribes described in the text.

Table 1 I-V Parameters for Four Mini-Modules with or without Isolation Scribes

Mini-Module Total AZO Film/Edges Cell Strip Voc Jsc FF Eff. Rs Rsh # Cell

File ID (μm) Reworked Area (cm2

) (V) (mA/cm2

) (%) (%) (ohm-cm2) (ohm-cm2) Strips

(a) All-Laser-Scribed

C2681-1 0.12 No 4.49 5.742 26.97 34.30 5.31 113.6 503.4 10

C2681-2 0.50 P3 & Isolate-1 3.90 5.846 26.74 46.32 7.24 81.9 697.2

C2681-2N (new meas.) 3.90 5.758 28.23 48.00 7.80 62.2 714.0

C2681-3N Manual scribe-1 3.58 5.810 28.50 50.58 8.38 57.6 728.4

C2681-4 Manual scribe-2 3.45 5.795 29.28 50.46 8.56 60.0 723.0

C2684-1 0.12 No 4.49 4.979 27.61 29.65 4.08 128.0 280.5 10

C2684-2 0.50 P3 4.23 5.975 26.76 51.93 8.30 48.1 726.0

C2684-2N (new meas.) 4.23 5.998 28.20 54.10 9.15 43.2 854.3

C2684-3N Manual scribe-1 3.74 6.001 28.22 54.18 9.18 48.7 832.7

(b) P1 Laser + P2/P3 Mechanical

C2682-2 0.50 Left half isolated 2.78 5.811 25.16 51.18 7.48 49.2 999.8 10

C2682-2N (new meas.) 2.78 5.752 26.59 49.59 7.59 54.5 890.7

C2683-2 0.50 No 4.06 5.458 25.19 48.22 6.63 50.3 761.1 9

C2683-2N (new meas.) 4.06 5.412 26.25 45.69 6.49 59.9 520.8
5

modules is insignificant here. From the intercepts of the 

semicircle on the real Z’ axis, Rs’ and Rp values can be 

easily obtained. C can be derived from curve fitting with 

the ZView software.

Table 2 summarizes the Rs and Rsh (in ohm-cm2

) from 

light I-V measurements (shown in Table 1 too) , Rs’ and 

Rp (in ohm) from ECIS measurements at 1 Hz and 1M Hz 

and curve fitting data, and effective minority-carrier lifetime 

(or time constant, in second) calculated from the product 

of Rp and C (in farad). The Rs’ and Rp values derived 

from curve fitting are generally close to the resistance 

values obtained directly for Z’ at 1 Hz and 1M Hz, 

respectively. Curve fitting results for all data show the 

mini-modules are better fitted with an equivalent circuit 

having a depressed “constant phase element (CPE-P)” 

factor (Table 2) [17,18]. The CPE-P, typically between 0.9 

and 1.0 (1.0 for an ideal case of capacitor), can be viewed 

as an indicator of the presence of interface or surface 

states on rough or porous surfaces [17,18]. The relatively

high contact/bulk resistance Rs’ and low recombination 

resistance Rp from dark ECIS measurements correspond 

to the high series resistance (Rs) and low shunt resistance 

(Rsh) from light I-V measurements, inevitably resulting in 

low fill factor (FF) and thus low performance efficiency of 

the four mini-modules. Upon manual scribes, the two 

laser-scribed mini-modules exhibit a small increase in the 

resistance of Z’ at 1 Hz, or Rp from curve fitting. The order 

of the performance efficiency of the mini-modules, which is 

C2684 (9.18%) > C2681 (8.56%) > C2682 (7.56%) > 

C2683 (6.49%) in Table 1, correlates somewhat better 

with the inverse order of contact/bulk resistance Rs’, which 

is C2684 (10.2 ohms) < C2681 (10.6) < C2683 (11.1) < 

C2682 (18.4) in Table 2, rather with the order of effective 

minority-carrier lifetime (or time constant, the product of 

Rp*C [13]), which gives C2683 > C2684 > C2681 > C2682.

More work with better scribe-isolation quality and higher 

performance CIGS mini-modules will be needed in order 

to establish a good correlation between the PV 

performance parameters and the electrical parameters

from ECIS measurements [19].

CONCLUSIONS

We have shown that PL and EL imaging (and LIT when 

available) are complementary with I-V and localized QE 

measurements in characterizing the performance of the 

experimental mini-modules. The PL and EL imaging are 

very useful in identifying the presence and location of 

performance-degrading spots/regions, where remedy 

treatment may be rendered – if physically practical – to 

improve performance efficiency. The ECIS analysis is 

sensitive to detect changes in electrical parameters of the 

mini-modules and also complementary to the I-V 

measurements. A prompt application from this study has 

been to employ the rapid PL imaging to detect the poor 

regions on the CdS-coated CIGS absorber and isolate

them in advance from making devices over those areas. 

ACKNOWLEDGEMENTS

We thank M. Contreras, T. Gessert, and R. Noufi for the 

support of this collaboration work and S. Johnston for the 

support of PL, EL, and LIT imaging work by F. Yan. This 

work was performed at the National Center for 

Photovoltaics under DOE Contract No. DE-AC36-

08GO28308 with the National Renewable Energy 

Laboratory. 

REFERENCES

[1] M. Powalla and B. Dimmler, “Process Development of 

High Performance CIGS Modules for Mass Production,” 

Thin Solid Films, 387, 2001, pp. 251–256. 

[2] M. Powalla, D. Hariskos, E. Lotter, M. Oertel, J. 

Springer, D. Stellbogen, B. Dimmler, and R. 

Schäffler, ”Large-Area CIGS Modules: Processes and 

Properties,” Thin Solid Films, 431-432, 2003, pp. 523–533.

[3] J. Palm, W. Stetter, S. Visbeck, T. Niessen, M. 

Furfanger, H. Vogt, J. Baumbach, H. Calwer, V. Probst, 

and F. Karg, “Pilot-Line CIGSSE Power Modules 

Processing and Qualification at Shell Solar,” Proc. 20th

EuPVSEC, June 6–10, 2005, Barcelona, Spain.

Table 2 (Electrochemical) Impedance Spectroscopy Analysis of Mini-Modules with or without Manual Scribes

From LIV Meas. From ECIS Meas. From Curve Fitting

Mini-Module AZO P1-P3 Scribe Manual Rs Rsh Z' (1M Hz) Z' (1 Hz) Rs' Rp C (F) Lifetime 

ID - State (μm) Method Scribe # (ohm-cm)(ohm-cm) (ohm) (ohm) (ohm) (ohm) or CPE-T CPE-P (Rp*C) (s)

C2681-2 0.50 All Laser 0 62.2 714.0 10.8 225.4 10.7 213.9 1.849E-08 0.945 3.954E-06

C2681-4 0.50 All Laser 2 60.0 723.0 10.0 244.9 10.6 233.1 1.335E-08 0.970 3.112E-06

C2684-2 0.50 All Laser 0 43.2 854.3 12.8 236.1 10.9 224.7 1.288E-08 0.981 2.895E-06

C2684-3N 0.50 All Laser 1 48.7 832.7 9.1 252.2 10.2 240.8 1.400E-08 0.974 3.371E-06

C2682-2N 0.50

P1 Laser, P2 & 

P3 Mechanical 0 54.5 890.7 11.9 465.8 18.4 445.8 9.065E-09 0.977 4.040E-06

C2683-2N 0.50

P1 Laser, P2 & 

P3 Mechanical 0 50.3 761.1 9.2 155.9 11.1 144.3 1.269E-08 0.983 1.831E-06
6

[4] M. Powalla, M. Cemernjak, J. Eberhardt, F. Kessler, R. 

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Modules: Pilot Line Production and New Developments,” 

Solar Energy Materials and Solar Cells, 90, 2006, pp.

3158–3164. 

[5] B. Dimmler and R. Wächter, “Manufacturing and 

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2007, pp. 5973-5978.

[6] A.D. Compaan, I. Matulionis, and S. Nakade,

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Final Technical Progress Report, 12 April 1995 – 11 

October 1997. The University of Toledo, Toledo, Ohio. 

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[7] A.D. Compaan (2000, Jan. 1), “Photovoltaics: Laser 

Scribing Creates Monolithic Thin-Film Arrays,” retrieved 

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http://www.laserfocusworld.com/articles/58212. 

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25, 2010, Honolulu, Hawaii.

[9] R. Murison, C. Dunsky, M. Rekow, C. Dinkel, F.J. Pern, 

L. Mansfield, T. Panarello, and S. Nikumb, “CIGS P1, P2, 

and P3 Laser Scribing With An Innovative Fiber Laser,” 

Proc. 35th IEEE PVSC, June 20-25, 2010, Honolulu, 

Hawaii.

[10] M. Rekow, R. Murison, C. Dunsky, C. Dinkel, J. Pern, 

L. Mansfield, T. Panarello, and S. Nikumb, “CIGS P1, P2, 

P3 Scribing Processes using a Pulse Programmable 

Industrial Fiber Laser,” Proc. of 25th EU PVSEC/WCPEC5, Sept. 6-10, 2010, Valencia, Spain.

[11] M. S. Suresh, “Measurement of Solar Cell Parameters 

using Impedance Spectroscopy,” Solar Energy Materials 

and Solar Cells, 43, 1996, pp. 21-28.

[12] J. Bisquert, “Theory of the Impedance of Electron 

Diffusion and Recombination in a Thin Layer,” J. Phys. 

Chem. B, 106, 2002, pp. 325-333.

[13] J. Bisquert, “Impedance Spectroscopy Applied on 

Solar Cells,” a presentation at the Nordic Workshop on 

Solar Electricity, Sonnerupgaard Gods, Denmark, 27-29 

April 2004.

[14] I. Mora-Sero, G. Garcia-Belmonte, P. P. Boix, M. A. 

Vazquez, and J. Bisquert, “Impedance Spectroscopy 

Characterisation of Highly Efficient Silicon Solar Cells 

under Different Light Illumination Intensities,” Energy 

Environ. Sci., 2, 2009, pp. 678–686.

[15] H. Bayhan and A. S. Kavasoglu, “Admittance and 

Impedance Spectroscopy on Cu(In,Ga)Se2 Solar Cells, 

Turk J. Phys. 27, 2003, pp. 529-535.

[16] H. Bayhan and A. S. Kavasoglu, “Study of 

CdS/Cu(In,Ga)Se2 Heterojunction interface Using 

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80, 2006, pp. 1160-1164.

[17] “Impedance Spectroscopy – Emphasizing Solid Sate 

Materials and Systems,” J. Ross MacDonald ed., John 

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Element” in Chapters 1 and 2.

[18] Help menu on equivalent circuits, instant curve fitting 

function and constant phase element in the ZView 

program (ver. 3.2c) from Scribner Associates, Inc.

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Otero, D. Kuang, S. M. Zakeeruddin, and M. Graetzel, 

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Based on Ionic Liquids,” J. Phys. Chem. C, 111, 2007, pp. 

6550-6560.