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Abstract A single-beam ion source was developed and used in combination with magnetron sputtering to modulate the film microstructure. The ion source emits a single beam of ions that interact with the deposited film and simultaneously enhances the magnetron discharge. The magnetron voltage can be adjusted over a wide range, from approximately 240 to 130 V, as the voltage of the ion source varies from 0 to 150 V, while the magnetron current increases accordingly. The low-voltage high-current magnetron discharge enables a ‘soft sputtering mode’, which is beneficial for thin-film growth. Indium tin oxide (ITO) thin films were deposited at room temperature using a combined single-beam ion source and magnetron sputtering. The ion beam resulted in the formation of polycrystalline ITO thin films with significantly reduced resistivity and surface roughness. Single-beam ion-source-enhanced magnetron sputtering has many potential applications in which low-temperature growth of thin films is required, such as coatings for organic solar cells.
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Development of Indium-tin Oxide Thin Films on PAMAM Dendrimer Layers for Perovskite Solar Cells Application
Despite the dramatic progress that has been made in the power-conversion efficiency (PCE) of perovskite solar cells (PVSCs), there are still many obstacles to be overcome before these devices can be economically competitive in the photovoltaics market. One of the major hurdles in the commercialization of PVSCs is low stability, which severely limits the effective lifetime of the devices. One of the approaches to achieving higher stability and lifetime of PVSCs is improvement of PVSC film quality. In this paper, we have employed a PAMAM dendrimer layer to reduce the surface roughness of sputter-deposited indium-tin oxide (ITO) films, which were then used in the fabrication of PVSCs. A PAMAM-8 dendrimer layer was deposited by dip-coating the substrates in 25 mL of a 1 μMPAMAM-8 ethanol solution before ITOdeposition. X-ray refractivity (XRR)was used to verify the PAMAMlayer on the substrate. ITOfilms of 150 nm thicknesswere then deposited onto the PAMAMlayer using DC magnetron reactive sputtering. The surface roughness, sheet resistance, and transmissivity of the ITO films were optimized by varying the parameters of the sputtering process. Atomic force microscopy (AFM) was used to measure the surface roughness of the ITO films with and without PAMAM dendrimer layer. A root-mean-square (RMS) film roughness of 1.6 nm, sheet resistance of 21 /ϒ, and transmissivity of > 91% at a wavelength of 400–700 nm were obtained after optimization.
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- Award ID(s):
- 2053954
- PAR ID:
- 10413859
- Date Published:
- Journal Name:
- Energy Technology 2023
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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