title: Liquid hydridosilane precursor prepared from cyclopentasilane via sonication at low temperatures without the action of light.
abstract: We report on a liquid hydridosilane precursor ink prepared via the ultrasonically induced ring-opening polymerisation of cyclopentasilane (Si5H10) without irradiation by ultraviolet light. The sonication is carried out in N2atmosphere at temperatures between 20 and 75°C. We use size exclusion chromatography (SEC) to show polymer growth and estimate molecular mass with increasing sonication time. In combination with UV-vis transmission measurements, further SEC analysis is used to compare solutions subjected to either purely thermal or ultrasonic treatment at the same process temperature and for the same duration. Our findings provide strong evidence showing that the initiation of the polymerisation is sonocatalytic in nature and not thermic due to the macroscopic temperature of the solution. The liquid precursor is used to produce homogeneous hydrogenated amorphous silicon (a-Si:H) thin films via spin coating and pyrolytic conversion. The optoelectronic properties of the films are subsequently improved by hydrogen radical treatment. Fourier transform infrared spectroscopy (FTIR) is used to determine a compact film morphology and electrical conductivity measurements show that the layers attain a light-to-dark photosensitivity ratio of 2×103making them suitable for application in optoelectronic devices.
authors: IEK-5, Photovoltaics, Forschungszentrum Jülich GmbH, Jülich, Germany. Electronic address: a.cadiz.bedini@fz-juelich.de.
authors: A P
authors: AP
authors: Cádiz Bedini
authors: IEK-5, Photovoltaics, Forschungszentrum Jülich GmbH, Jülich, Germany.
authors: S
authors: S
authors: Muthmann
authors: JCNS-1, Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Jülich, Germany.
authors: J
authors: J
authors: Allgaier
authors: IEK-5, Photovoltaics, Forschungszentrum Jülich GmbH, Jülich, Germany.
authors: K
authors: K
authors: Bittkau
authors: IEK-5, Photovoltaics, Forschungszentrum Jülich GmbH, Jülich, Germany.
authors: F
authors: F
authors: Finger
authors: IEK-5, Photovoltaics, Forschungszentrum Jülich GmbH, Jülich, Germany.
authors: R
authors: R
authors: Carius
keywords: Acoustic cavitation; Higher silicon hydrides; Printable ink; Ring-opening polymerisation; Solution-processed