TY - JOUR

T1 - Design of Large Poly‐Si on Oxide Interdigitated Back Contact (POLO IBC) Silicon Solar Cells with Local Al–p + Contacts in the Constraints of Measurement and Module Integration

AU - Haase, Felix

AU - Hollemann, Christina

AU - Wehmeier, Nadine

AU - Bothe, Karsten

AU - Min, Byungsul

AU - Schulte-Huxel, Henning

AU - Brendel, Rolf

AU - Peibst, Robby

N1 - Funding Information: The authors would like to thank A. Christ, D. Sylla, A. Raugewitz, R. Winter, M. Pollmann, T. Neubert, U. Baumann, S. Blankemeyer, I. Kunze (all ISFH), and R. Zieseniß (Institute of Electronic Materials and Devices) for sample processing and measuring, and B. Fischer (pv‐tools) for designing and calibrating the measurement chuck. The authors also thank TOYO Aluminum for providing the Al‐paste, Heraeus, and Dupont for the Ag‐pastes, and LONGI for providing the wafer material. This work was funded by the state of Lower Saxony and the Federal Ministry for Economic Affairs and Climate Action (BMWK) under grant number 0324275A (Street).

PY - 2022/11/8

Y1 - 2022/11/8

N2 - Interdigitated back contact (IBC) silicon solar cells with a passivating n-type poly-Si on oxide emitter and an aluminum-doped p+ base contact on M2-sized Ga-doped p-type Cz wafers are reported. The Al-doped base contact forms during the firing of the printed contacts and allows for a lean process flow. The device optimization balances recombination at the base contacts against resistive losses and respects constraints set by the need of interconnecting cells in a module and contacting the cells temporally by a measurement chuck. A special sample holder is designed for measuring the Isc–Voc curve of the IBC cell with a busbar-less metal grid. The pseudo-efficiency is 24.7%. All fingers of each polarity are connected with wires and an efficiency of 22.3% is measured. The comparison of simulations and measurements reveals that the cell has 23.4% efficiency without the series resistance losses due to the wires. A huge part of the resistive losses in the cell are the transport losses of the majorities in the base dissipating a power that corresponds to 0.76%abs efficiency and the resistive losses at the Al-doped base contact (0.29%abs).

AB - Interdigitated back contact (IBC) silicon solar cells with a passivating n-type poly-Si on oxide emitter and an aluminum-doped p+ base contact on M2-sized Ga-doped p-type Cz wafers are reported. The Al-doped base contact forms during the firing of the printed contacts and allows for a lean process flow. The device optimization balances recombination at the base contacts against resistive losses and respects constraints set by the need of interconnecting cells in a module and contacting the cells temporally by a measurement chuck. A special sample holder is designed for measuring the Isc–Voc curve of the IBC cell with a busbar-less metal grid. The pseudo-efficiency is 24.7%. All fingers of each polarity are connected with wires and an efficiency of 22.3% is measured. The comparison of simulations and measurements reveals that the cell has 23.4% efficiency without the series resistance losses due to the wires. A huge part of the resistive losses in the cell are the transport losses of the majorities in the base dissipating a power that corresponds to 0.76%abs efficiency and the resistive losses at the Al-doped base contact (0.29%abs).

KW - current–voltage measurements

KW - free energy loss analyses

KW - POLO IBC

KW - poly-silicon

KW - simulations

UR - http://www.scopus.com/inward/record.url?scp=85138679873&partnerID=8YFLogxK

U2 - 10.1002/solr.202200583

DO - 10.1002/solr.202200583

M3 - Article

AN - SCOPUS:85138679873

VL - 6

JO - Solar RRL

JF - Solar RRL

IS - 11

M1 - 2200583

ER -