Polycrystalline Si on SiOx passivating contacts enables some of the highest efficiency single-junction Si photovoltaic devices, but the high-temperature firing process needed for industrial metallization can significantly reduce passivation. We show that after firing, the implied open-circuit voltage, iVoc, for the Al2O3/SiNx/poly-Si/SiOx/c-Si stack is 20-30 mV higher than the SiNx/Al2O3/poly-Si/SiOx/c-Si stack and therefore provides better passivation of the SiOx/c-Si interface. Using effusion measurements and Fourier transform infrared spectroscopy, we demonstrate that more than twice as much hydrogen is retained in the dielectric up to the peak firing temperature of ~800 degrees C for Al2O3-capped structures. If the Al2O3 layer is not present in the stack, after firing, the iVoc is lower by 50-100 mV compared to Al2O3/SiNx or SiNx/Al2O3 stacks. These studies will inform future work on the role of dielectrics in aiding the passivation of poly-Si/SiOx passivating contacts.
Hartenstein, Matthew B., et al. "Hydrogen Stability and Bonding in SiN<sub><em>x</em></sub> and Al<sub>2</sub>O<sub>3</sub> Dielectric Stacks on Poly-Si/SiO<sub><em>x</em></sub> Passivating Contacts." ACS Applied Energy Materials, vol. 6, no. 13, Jun. 2023. https://doi.org/10.1021/acsaem.3c00937
Hartenstein, Matthew B., Nemeth, William, Young, David L., Stradins, Paul, & Agarwal, Sumit (2023). Hydrogen Stability and Bonding in SiN<sub><em>x</em></sub> and Al<sub>2</sub>O<sub>3</sub> Dielectric Stacks on Poly-Si/SiO<sub><em>x</em></sub> Passivating Contacts. ACS Applied Energy Materials, 6(13). https://doi.org/10.1021/acsaem.3c00937
Hartenstein, Matthew B., Nemeth, William, Young, David L., et al., "Hydrogen Stability and Bonding in SiN<sub><em>x</em></sub> and Al<sub>2</sub>O<sub>3</sub> Dielectric Stacks on Poly-Si/SiO<sub><em>x</em></sub> Passivating Contacts," ACS Applied Energy Materials 6, no. 13 (2023), https://doi.org/10.1021/acsaem.3c00937
@article{osti_1993046,
author = {Hartenstein, Matthew B. and Nemeth, William and Young, David L. and Stradins, Paul and Agarwal, Sumit},
title = {Hydrogen Stability and Bonding in SiN<sub><em>x</em></sub> and Al<sub>2</sub>O<sub>3</sub> Dielectric Stacks on Poly-Si/SiO<sub><em>x</em></sub> Passivating Contacts},
annote = {Polycrystalline Si on SiOx passivating contacts enables some of the highest efficiency single-junction Si photovoltaic devices, but the high-temperature firing process needed for industrial metallization can significantly reduce passivation. We show that after firing, the implied open-circuit voltage, iVoc, for the Al2O3/SiNx/poly-Si/SiOx/c-Si stack is 20-30 mV higher than the SiNx/Al2O3/poly-Si/SiOx/c-Si stack and therefore provides better passivation of the SiOx/c-Si interface. Using effusion measurements and Fourier transform infrared spectroscopy, we demonstrate that more than twice as much hydrogen is retained in the dielectric up to the peak firing temperature of ~800 degrees C for Al2O3-capped structures. If the Al2O3 layer is not present in the stack, after firing, the iVoc is lower by 50-100 mV compared to Al2O3/SiNx or SiNx/Al2O3 stacks. These studies will inform future work on the role of dielectrics in aiding the passivation of poly-Si/SiOx passivating contacts.},
doi = {10.1021/acsaem.3c00937},
url = {https://www.osti.gov/biblio/1993046},
journal = {ACS Applied Energy Materials},
issn = {ISSN 2574-0962},
number = {13},
volume = {6},
place = {United States},
publisher = {American Chemical Society (ACS)},
year = {2023},
month = {06}}