Junction Resistivity of Carrier-Selective Polysilicon on Oxide Junctions and Its Impact on Solar Cell Performance

authored by

Michael Rienacker, Marcel Bossmeyer, Agnes Merkle, Udo Romer, Felix Haase, Jan Krugener, Rolf Brendel, Robby Peibst

Abstract

We investigate the junction resistivity of high quality carrier selective polysilicon on oxide (POLO) junctions with the transfer length method. We demonstrate n ⁺ POLO junctions with a saturation current density J _{c, poly} of 6.2 fA/cm ² and junction resistivity p _c of 0.6 mΩcm ² , counterdoped n ⁺ POLO junctions with 2.7 fA/cm ² and 1.3 mΩcm ² , and p ⁺ POLO junctions with 6.7 fA/cm ² and 0.2 mΩcm ² . Such low junction resistivities and saturation current densities correspond to excellent selectivities of up to 16.2 and imply a contribution of only a few mΩcm ² to the total series resistance of the cell, enabling an efficiency potential larger than 26 %, which was estimated by numerical device simulations. We demonstrate experimentally a back-junction back contacted solar cell with p-type and n-type POLO junctions with an efficiency of 23.9 %. This efficiency is the largest reported so far for cells with polysilicon junctions for both contacts and it is limited by the passivation of undoped regions.

Organisation(s)

Institute of Electronic Materials and Devices
Institute of Solid State Physics

External Organisation(s)

University of New South Wales (UNSW)
Institute for Solar Energy Research (ISFH)

Type

Article

Journal

IEEE Journal of Photovoltaics

Volume

7

Pages

11-18

No. of pages

8

ISSN

2156-3381

Publication date

01.2017

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials, Condensed Matter Physics, Electrical and Electronic Engineering

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1109/PVSC.2017.8366491 (Access: Closed)
https://doi.org/10.1109/JPHOTOV.2016.2614123 (Access: Closed)