Inductively coupled plasma chemical vapour deposited AlO _x/SiN_y layer stacks for applications in high-efficiency industrial-type silicon solar cells

verfasst von

T. Dullweber, C. Kranz, B. Beier, B. Veith, J. Schmidt, B. F.P. Roos, O. Hohn, T. Dippell, R. Brendel

Abstract

Passivated emitter and rear cells (PERC) are considered to be the next generation of industrial-type screen-printed silicon solar cells. Deposition methods for rear passivation layers have to meet both the high-throughput and low-cost requirements of the PV industry in combination with high-quality surface passivation properties. In this paper, we evaluate and optimise a novel deposition technique for AlO_x passivation layers by applying an inductively coupled plasma (ICP) plasma-enhanced chemical vapour deposition (PECVD) process. The ICP AlO_x deposition process enables high deposition rates up to 5 nm/s as well as excellent surface recombination velocities below 10 cm/s after firing. A fixed negative charge of -4×10¹² cm^-2 is measured for ICP AlO_x single layers with an interface state density of 11.0×10¹¹ eV^-1 cm^-2 at midgap position. When applied to PERC solar cells the ICP AlO_x layer is capped with a PECVD SiN_y layer. We achieve independently confirmed conversion efficiencies of up to 20.1% for large-area (15.6×15.6 cm²) PERC solar cells with screen-printed metal contacts and ICP AlO_x/SiN_y rear side passivation on standard boron-doped Czochralski-grown silicon wafers. The internal quantum efficiency reveals an effective rear surface recombination velocity S_rear of (90±30) cm/s and an internal rear reflectance R_b of (91±1)% which demonstrates the excellent rear surface passivation of the ICP AlO_x/SiN_y layer stack.

Organisationseinheit(en)

Abt. Solarenergie

Externe Organisation(en)

Institut für Solarenergieforschung GmbH (ISFH)
Singulus Technologies AG

Typ

Artikel

Journal

Solar Energy Materials and Solar Cells

Band

112

Seiten

196-201

Anzahl der Seiten

6

ISSN

0927-0248

Publikationsdatum

2013

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Elektronische, optische und magnetische Materialien, Erneuerbare Energien, Nachhaltigkeit und Umwelt, Oberflächen, Beschichtungen und Folien

Ziele für nachhaltige Entwicklung

SDG 7 – Erschwingliche und saubere Energie

Elektronische Version(en)

https://doi.org/10.1016/j.solmat.2013.01.036 (Zugang: Unbekannt)