How the Chlorine Treatment and the Stoichiometry Influences the Grain Boundary Passivation in Polycrystalline CdTe Thin Films
Abstract
:1. Introduction
2. Experimental
2.1. The Solar Cell
2.2. Characterization
3. Results and Discussion
3.1. The Chlorine Treatment
3.2. Pinholes and Grain Boundaries Passivation
4. Conclusions
Author Contributions
Conflicts of Interest
References
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Product of Dissociation | |||||||
---|---|---|---|---|---|---|---|
Substance | Amu | Substance | Amu | Substance | Amu | Substance | Amu |
C(n) | 12 | 35Cl(n) | 35 | HF2(i) | 39 | CH2Cl(i) | 49 |
CH(i) | 13 | H35Cl(n)/36Ar(n) | 36 | 4Ar(n) | 40 | CHF2(i) | 51 |
CH2F(i) | 31 | 37Cl(n) | 37 | CCl(i) | 47 | CF35Cl(i) | 66 |
CH2F(i) | 33 | H37Cl(i) | 38 | CHCl(i) | 48 | C2F4(n) | 100 |
(n) = neutral; (i) = ionic |
Treatment Conditions | Photovoltaic and Diode Parameters | ||||||
---|---|---|---|---|---|---|---|
Temperature [K] | Pressure [Pa] | Time [min] | Nr of Cells | Rs * [ohm] | Rsh * [ohm] | Efficiency [%] | |
LCHY | Ar | ||||||
CHClCCl2 (1,1,2-Trichloroethylene) | |||||||
673 | 200 | 4.98 × 104 | 15 | 25 | 1.8 ± 0.9 | 87 ± 11 | 9.3 ± 1.1 |
500 | 4.95 × 104 | 10 | 19 | 1.5 ± 0.4 | 59 ± 9.3 | 5.7 ± 1.7 | |
CH2Cl2 (Dichloromethane) | |||||||
673 | 100 | 4.99 × 104 | 15 | 25 | 2.2 ± 0.9 | 82 ± 9.9 | 8.8 ± 0.9 |
500 | 4.95 × 104 | 10 | 22 | 1.1 ± 0.6 | 63 ± 8.7 | 6.5 ± 1.5 | |
CH3(CH2)3Cl (1-Chlorobutane) | |||||||
673 | 200 | 4.98 × 104 | 15 | 20 | 1.8 ± 1.1 | 77 ±12 | 7.8 ± 1.4 |
500 | 4.95 × 104 | 10 | 23 | 0.9 ± 0.5 | 58 ± 11 | 5.4 ± 2.2 |
Fluorinated Hydrocarbons | |||||
---|---|---|---|---|---|
Trade Name | Name | Chemical Formula | Trade Name | Name | Chemical Formula |
R-23 | Trifluoromethane | CHF3 | R-32 | Difluoromethane | CH2F2 |
R-125 | Pentafluoroethane | CHF2CF3 | R-134a | 1,1,1,2-Tetrafluorethane | CH2FCF3 |
R-143a | 1,1,1-Trifluoroethane | CH3CF3 | R-152a | 1,1-Difluoroethane | CH3CHF2 |
Photovoltaic and Diode Parameters | ||||
---|---|---|---|---|
Gas Mixture | Nr of Cells | Rs * [ohm] | Rsh * [ohm] | Efficiency [%] |
Ar + CHClCCl2 + R-134a | 23 | 1.2 ± 0.02 | 1657 ± 20 | 15.7 ± 0.5 |
Ar + CH2Cl2 + R-134a | 32 | 1.5 ± 0.04 | 1550 ± 9 | 14.6 ± 0.5 |
Ar + R-22 | 50 | 0.8 ± 0.01 | 1870 ± 5 | 15.8 ± 0.3 |
Ar + HCl + R23 | 50 | 1.1 ± 0.01 | 1900 ± 5 | 16.2 ± 0.2 |
Sample | Voc (mV) | Jsc (mA) | FF (%) | Eff. (%) | Rs * [ohm] | Rsh * [ohm] |
---|---|---|---|---|---|---|
# 5333 | 830 | 25.2 | 70.01 | 14.94 | 5.6 ± 0.02 | 1428 ± 20 |
# 5591 | 860 | 26.1 | 59.2 | 13.19 | 10.6 ± 0.04 | 1250 ± 9 |
# 5561 | 786 | 24.5 | 50.4 | 9.36 | 14.2 ± 0.01 | 227 ± 5 |
EDX Scan Along Grain Boundary | EDX Scan Inside Grain | |||||||
---|---|---|---|---|---|---|---|---|
# | S | Cl | Cd | Te | # | S | Cd | Te |
1 | 29.3 | 4.9 | 42.4 | 23.4 | 1 | 4.4 | 46.2 | 49.4 |
2 | 16.1 | 4.8 | 35.0 | 44.1 | 2 | 3.2 | 47.3 | 49.5 |
3 | 24.4 | 4.0 | 45.4 | 26.2 | 3 | 2.1 | 48.2 | 49.7 |
4 | 17.1 | 5.1 | 44.7 | 33.1 | 4 | 3.0 | 47.3 | 49.7 |
5 | 3.2 | 47.7 | 49.1 | 5 | 2.3 | 47.8 | 49.8 | |
6 | 2.9 | 50.7 | 46.4 | 6 | 48.5 | 51.5 | ||
7 | 2.9 | 49.3 | 47.8 | 7 | 51.2 | 48.8 | ||
8 | 2.5 | 49.4 | 48.1 | 8 | 51.3 | 48.7 | ||
9 | 2.8 | 49.7 | 47.5 | |||||
10 | 3.0 | 49.2 | 47.8 | |||||
11 | 2.7 | 50.8 | 46.5 |
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Bosio, A.; Rosa, G.; Menossi, D.; Romeo, N. How the Chlorine Treatment and the Stoichiometry Influences the Grain Boundary Passivation in Polycrystalline CdTe Thin Films. Energies 2016, 9, 254. https://doi.org/10.3390/en9040254
Bosio A, Rosa G, Menossi D, Romeo N. How the Chlorine Treatment and the Stoichiometry Influences the Grain Boundary Passivation in Polycrystalline CdTe Thin Films. Energies. 2016; 9(4):254. https://doi.org/10.3390/en9040254
Chicago/Turabian StyleBosio, Alessio, Greta Rosa, Daniele Menossi, and Nicola Romeo. 2016. "How the Chlorine Treatment and the Stoichiometry Influences the Grain Boundary Passivation in Polycrystalline CdTe Thin Films" Energies 9, no. 4: 254. https://doi.org/10.3390/en9040254
APA StyleBosio, A., Rosa, G., Menossi, D., & Romeo, N. (2016). How the Chlorine Treatment and the Stoichiometry Influences the Grain Boundary Passivation in Polycrystalline CdTe Thin Films. Energies, 9(4), 254. https://doi.org/10.3390/en9040254