Highly transparent RF magnetron-sputtered indium tin oxide films for a-Si:H/c-Si heterojunction solar cells amorphous/crystalline silicon

Zhang

ACS Appl. Mater. Interfaces

et al. 2014

We have investigated the role of hydrogen plasma pretreatment in promoting silicon surface passivation, in particular examining its effects on modifying the microstructure of the subsequently deposited thin hydrogenated amorphous silicon (a-Si:H) passivation film. We demonstrate that pretreating the silicon surface with hydrogen plasma for 40 s improves the homogeneity and compactness of the a-Si:H film by enhancing precursor diffusion and thus increasing the minority carrier lifetime (τ(eff)). However, excessive pretreatment also increases the density of dangling bond defects on the surface due to etching effects of the hydrogen plasma. By varying the duration of hydrogen plasma pretreatment in fabricating silicon heterojunction solar cells based on textured substrates, we also demonstrate that, although the performance of the solar cells shows a similar tendency to that of the τ(eff) on polished wafers, the optimal duration is prolonged owing to the differences in the surface morphology of the substrates. These results suggest that the hydrogen plasma condition must be carefully regulated to achieve the optimal level of surface atomic hydrogen coverage and avoid the generation of defects on the silicon wafer.

Section: Introductionmentioning

confidence: 99%

Role of Hydrogen Plasma Pretreatment in Improving Passivation of the Silicon Surface for Solar Cells Applications

Zhang

ACS Appl. Mater. Interfaces

et al. 2014

“…Figure 6 d shows the carrier lifetime of PV cells for different RF powers [ 90 ]. S. Ahn et al reported that the device performance of HJ solar cells is enhanced when the [Oi] in the ITO film is increased.…”

Section: Current Challenges and Future Outlookmentioning

confidence: 99%

“…The resulting IO: H electrodes showed some promising properties of high carrier concentration (N) = 1.5 × 10 20 cm −3 , mobility (µ) = 140 cm 2 /(V•s) cm, respectively, and a quite low resistivity (ρ) = 2.9 × 10 −4 (Ω•cm) [97]. Figure 6d shows the carrier lifetime of PV cells for different RF powers [90]. S. Ahn et al reported that the device performance of HJ solar cells is enhanced when the [Oi] in the ITO film is increased.…”

Section: Current Challenges and Future Outlookmentioning

confidence: 99%

A Brief Review of Transparent Conducting Oxides (TCO): The Influence of Different Deposition Techniques on the Efficiency of Solar Cells

et al. 2023

Self Cite

Global-warming-induced climate changes and socioeconomic issues increasingly stimulate reviews of renewable energy. Among energy-generation devices, solar cells are often considered as renewable sources of energy. Lately, transparent conducting oxides (TCOs) are playing a significant role as back/front contact electrodes in silicon heterojunction solar cells (SHJ SCs). In particular, the optimized Sn-doped In2O3 (ITO) has served as a capable TCO material to improve the efficiency of SHJ SCs, due to excellent physicochemical properties such as high transmittance, electrical conductivity, mobility, bandgap, and a low refractive index. The doped-ITO thin films had promising characteristics and helped in promoting the efficiency of SHJ SCs. Further, SHJ technology, together with an interdigitated back contact structure, achieved an outstanding efficiency of 26.7%. The present article discusses the deposition of TCO films by various techniques, parameters affecting TCO properties, characteristics of doped and undoped TCO materials, and their influence on SHJ SC efficiency, based on a review of ongoing research and development activities.

IEEJ Transactions Elec Engng

“…The most important parameters of a high‐quality ITO film are the electrical resistivity and optical transmittance. ITO films are deposited via various techniques including spray pyrolysis , the sol–gel method , pulsed laser deposition , and magnetron sputtering . Among the various techniques, magnetron sputtering has certain advantages such as high deposition rates, low deposition pressures, high‐quality films, greater adherence, better uniformity over large areas, and low substrate temperature during deposition.…”

Section: Introductionmentioning

confidence: 99%

“…Among the various techniques, magnetron sputtering has certain advantages such as high deposition rates, low deposition pressures, high‐quality films, greater adherence, better uniformity over large areas, and low substrate temperature during deposition. Furthermore, the film properties can be controlled by varying the sputtering parameters such as the substrate temperature , operating pressure , reactive gas combinations , sputtering power , and thermal annealing . The DC power used is one of the most critical process parameters, since it influences the film quality and its structural, electrical, and optical properties.…”

Section: Introductionmentioning

confidence: 99%

Role of sputtering power on the microstructural and electro‐optical properties of ITO thin films deposited using DC sputtering technique

Kosarian

Shakiba

Farshidi

2017

The effects of sputtering power on the deposition rate as well as the microstructural, electrical, and optical properties of indium tin oxide (ITO) thin films are investigated in this paper. ITO thin films were deposited on glass substrates using direct current (DC) magnetron sputtering of different DC powers, ranging from 60 to 140 W, onto externally unheated glass substrates. All samples were grown at the minimum sustainable plasma pressure to reduce the destructive role of pressure. The microstructural, electrical, and optical properties of the sputtered ITO films were systematically characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), four-probe electrical conductivity, and optical spectroscopy. XRD studies confirmed the cubic bixbyite ITO structure, and the main preferred orientations of the prepared thin films were (222), (400), (440), and (622). AFM analysis showed a minimum surface roughness of 1.37 nm for the films deposited at 140 W, while the average size of the grains was 65 ± 5 nm. The deposition time was fixed at 10 min for all samples, and the AFM characterization of the films showed 170, 230, and 250 nm thickness for the samples deposited at 60, 100 and 140 W, respectively. From the variations of the sheet resistance and the XRD patterns of the ITO thin films, it was concluded that, as the ratio I 222 /I 400 of a sample approaches unity, the sheet resistance of the layer reduces. A minimum sheet resistance 16 /square, transmittance 85% with the thickness of 230 nm, and optical bandgap 4.09 eV were found for the thin film grown on the externally unheated substrates at 100 W DC power and 32 mTorr working pressure.