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Book Crystalline Silicon Surface Passivation by Amorphous Silicon Compounds

Download or read book Crystalline Silicon Surface Passivation by Amorphous Silicon Compounds written by Roman Petres and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2011-09 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solar cells based on crystalline silicon (c-Si) have the potential to make photovoltaic electricity cheaper than coal-based electric power generation within less than 10 years. The largest cost decrease potential on the cell level lies with improved electronic surface passivation. In this work, the current industry standard, amorphous silicon nitride (a-SiNx: H) deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD), is investigated and compared to amorphous silicon carbide, silicon carbonitride and silicon oxynitride films deposited by both high- and for the first time also low-frequency (LF) PECVD. It is shown that and an explanation offered as to why LF PECVD is capable of excellent surface passivation, comparable to remote-plasma results in literature and higher than previously published for LF PECVD. The achieved surface passivation quality is sufficient for dielectric rear-surface passivation without an underlying diffused back surface field. It is also shown that the purity grade of precursor gases used for film deposition can be lowered significantly without affecting cell efficiency and long-term stability on the module level, allowing for further cost reduction

Book Surface Passivation of Crystalline Silicon Solar Cells by Amorphous Silicon Films

Download or read book Surface Passivation of Crystalline Silicon Solar Cells by Amorphous Silicon Films written by Heiko Plagwitz and published by . This book was released on 2007 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Characterization of Surface Passivation of Crystalline Silicon by Hydrogenated Amorphous Silicon Using Photocarrier Radiometry

Download or read book Characterization of Surface Passivation of Crystalline Silicon by Hydrogenated Amorphous Silicon Using Photocarrier Radiometry written by Keith R. Leong and published by . This book was released on 2006 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the silicon heterojunction solar cell, the crystalline silicon (c-Si) surface forms an interface with hydrogenated amorphous silicon (a-Si:H). This thesis reports on the development and evaluation of surface passivation schemes of c-Si with a-Si:H. The passivation consists of a three step process: cleaning of the c-Si surface, etching of the native oxide, and deposition the a-Si:H layer. Evaluation of the passivation schemes was conducted by recombination lifetime measurements using Photocarrier Radiometry (PCR). The SPM, RCA SC1, and SC2 cleaning sequence, followed by either buffered HF, and the growth of the a-Si:H film produced the highest PCR characteristic lifetime (80.9 mus). In the high injection regime, lifetime from PCR correlated with that from mu-PCD within a factor of 1.2 to 2.5. PCR laser annealing of the a-Si:H was observed for laser intensities at or above 2.9 suns. ToF-SIMS measurements identified Na, K, Ca, O, and SiO2 contaminants at the interface.

Book Surface Passivation of Crystalline Silicon by Amorphous Silicon Carbide Films for Photovoltaic Applications

Download or read book Surface Passivation of Crystalline Silicon by Amorphous Silicon Carbide Films for Photovoltaic Applications written by Rafel Ferré Tomàs and published by . This book was released on 2008 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Surface Passivation of Crystalline Silicon by Dual Layer Amorphous Silicon Films

Download or read book Surface Passivation of Crystalline Silicon by Dual Layer Amorphous Silicon Films written by Dmitri S. Stepanov and published by . This book was released on 2011 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Response Surface Methodology is used in this work to optimize the deposition conditions of SiNx. Optimization of the response surface function yielded deposition conditions that materialized in a surface recombination velocity of less than 4cm/s. The BACH (Back Amorphous Crystalline silicon Heterojunction) cell concept makes use of this dual layer a-Si:H/SiN x stack to form a high efficiency photovoltaic device. The high quality passivating structure can result in the BACH solar cell device with more than 20% conversion efficiency.The probability of recombination of photogenerated electron hole pairs in crystalline silicon is governed by the density of surface defect states and the density of charge carriers. Depositions of intrinsic hydrogenated amorphous silicon (a-Si:H) in dc saddle field (DCSF) PECVD system and hydrogenated amorphous silicon nitride (SiNx) in rf PECVD system forms a dual layer stack on c-Si, which results in an excellent passivation of the surface and an anti-reflection coating.

Book Crystalline Silicon Surface Passivation Using Aluminum Oxide Fundamental Understanding and Application to Solar Cells

Download or read book Crystalline Silicon Surface Passivation Using Aluminum Oxide Fundamental Understanding and Application to Solar Cells written by Boris Adrian Veith-Wolf and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Silicon Surface and Heterojunction Interface Passivation Studies by Lifetime Measurements

Download or read book Silicon Surface and Heterojunction Interface Passivation Studies by Lifetime Measurements written by and published by . This book was released on 2003 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report two investigations conducted by using photoconductivity decay lifetime measurement. The first is crystalline silicon (c-Si) surface passivation using quinhydrone/methanol (QM) for bulk minority-carrier lifetime measurement. QM shows great promise as a substitute for iodine-based solutions because of its superior stability and minimized surface-recombination velocity in silicon. The second is interface passivation in an amorphous silicon (a-Si)/c-Si heterojunction structure as a parallel effort to develop and optimize heterojunction c-Si solar cells by hot-wire chemical vapor deposition (HWCVD). A thin buffer layer inserted between the a-Si and the c-Si substrate has been found to be much more effective than a directly deposited a-Si/c-Si interface in reducing the interface recombination velocity.

Book Aluminum Oxide for the Surface Passivation of High Efficiency Silicon Solar Cells

Download or read book Aluminum Oxide for the Surface Passivation of High Efficiency Silicon Solar Cells written by Armin Richter and published by . This book was released on 2015-02-23 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Sputtered Aluminium Oxide and Amorphous Silicon for Silicon Solar Cells

Download or read book Sputtered Aluminium Oxide and Amorphous Silicon for Silicon Solar Cells written by Xinyu Zhang and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-efficiency silicon solar cells have been attracting an increased interest in recent years. Surface passivation is essential for various types of high-performance solar cells, particularly when thinner silicon wafers are used to reduce the material cost. Passivating dielectric thin films have been widely studied and used in solar cells designs, these include atomic-layer deposited (ALD) aluminium oxide, plasma-enhanced chemical vapour deposited (PECVD) silicon nitride and PECVD intrinsic amorphous silicon. The aim of this thesis is to develop and optimise an alternative deposition method for surface passivating films: sputtering. Sputtering is especially attractive for industrial production, due to its high throughput, easy and safe operation and global cost-effectiveness. This thesis has focussed on optimising the reactive sputtering of aluminium oxide, using an aluminium target, and the non-reactive sputtering of amorphous silicon, using a silicon target. A key innovation has been the addition of hydrogen to the mix of gasses that form the plasma, which permits to incorporate hydrogen into the films, leading to a significantly improved surface passivation quality compared to non-hydrogenated films. We have achieved the best surface passivation results by sputtered aluminium oxide to date, with an effective surface recombination velocity of 1 cm/s on 1.5 ohm-cm n-type silicon. This result is similar to the SRV of 0.9 cm/s measured on aluminium oxide films deposited by PA-ALD on the same substrates. Good passivation was also achieved on p-type silicon. The investigations into the reactive sputtering process have shown that the film properties are closely related to the oxidation level of the aluminium target, which can be controlled by adjusting process parameters. It has also been found that the presence of hydrogen in the plasma is beneficial for establishing the optimum conditions of the deposition; not only does the surface passivation quality improve, but the reactive sputtering process becomes easier to control as well.We have also shown - for the first time - that intrinsic amorphous silicon (a-Si:H) films by sputtering deposition are capable of providing an excellent passivation of crystalline silicon surfaces. A SRV of 1.5 cm/s on 1.5 ohm-cm n-type silicon and SRV of 9 cm/s on 1 ohm-cm p-type silicon have been achieved, which are comparable to the commonly used PECVD deposited a-Si:H films. After investigating the film properties using Fourier Transform Infrared Spectroscopy (FTIR), we observe that our sputtered a-Si:H films have a characteristic signature in terms of chemical bonding configurations, where several types of silicon-hydrogen bonds exist. From those measurements we have estimated that there is approximately a 4% hydrogen concentration in the films, sufficient to achieve excellent surface passivation. Finally, the thesis also presents initial attempts at developing doped amorphous silicon films, which could enable the development of an all-sputtered silicon heterojunction solar cell technology. Lightly doped a-Si:H films were deposited using a 1% boron doped silicon target and a 0.01% phosphorus doped silicon target. We have found an appropriate way to avoid surface passivation degradation caused by the doped layer deposition onto an intrinsic a-Si:H layer.

Book New Perspectives on Surface Passivation Understanding the Si Al2O3 Interface

Download or read book New Perspectives on Surface Passivation Understanding the Si Al2O3 Interface written by Lachlan E. Black and published by Springer. This book was released on 2016-04-15 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book addresses the problem of passivation at the surface of crystalline silicon solar cells. More specifically, it reports on a high-throughput, industrially compatible deposition method for Al2O3, enabling its application to commercial solar cells. One of the main focus is on the analysis of the physics of Al2O3 as a passivating dielectric for silicon surfaces. This is accomplished through a comprehensive study, which moves from the particular, the case of aluminium oxide on silicon, to the general, the physics of surface recombination, and is able to connect theory with practice, highlighting relevant commercial applications.

Book Surface Passivation of Industrial Crystalline Silicon Solar Cells

Download or read book Surface Passivation of Industrial Crystalline Silicon Solar Cells written by Joachim John and published by Institution of Engineering and Technology. This book was released on 2018-11-15 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface passivation of silicon solar cells describes a technology for preventing electrons and holes to recombine prematurely with one another on the wafer surface. It increases the cell's energy conversion efficiencies and thus reduces the cost per kWh generated by a PV system.