Download or read book Thin Film Transistors Using Nanocrystalline Silicon from Metal Induced Growth written by Xueli Hao and published by . This book was released on 2012 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin film transistors (TFTs) have been well developed in over six decades. Nowadays, hydrogenated amorphous silicon (a-Si:H) has been largely used for active matrix liquid crystal display (AMLCD) in the industrial field. At the same time, nanocrystalline silicon (nc-Si) TFT has attracted more attention due to its better quality than a-Si and low costs. This thesis focused on the fabrication of nc-Si TFTs using metal-induced growth (MIG), which has been utilized in solar cell fabrication and nanowire growth. The 500 ©5 thickness palladium (Pd) was evaporated as the metal catalyst on the silicon substrate covered with silicon dioxide. The nc-Si films were deposited using two-step DC sputtering at 625 °C. The Pd was consumed to form Pd2Si at 50 W low power step, which provides the nucleation sites for nc-Si growth. Then, nc-Si films can be grown at a high deposition rate which was obtained in the 150 W high power step.^As a result, the nc-Si with around 1000 nm thickness was deposited as the active channel of the TFTs by 45 min low power and 30 min high power sputtering. The output and transfer characteristics of the TFTs were illustrated in the thesis. The field effect mobility and the threshold voltage were calculated. The performance was difficult to get saturation due to the high leakage current. The field effect mobility values were 0. 3 to 0. 6 cm2/V. s, which were relatively low. The main reasons are the existence of the grain boundaries and the intragrain defects in the channel, the metal contamination introduced by MIG, and the thick channel layer. The threshold voltage values varied from 1. 3 V to 1. 9 V, which were partially affected by the short length effect (L= 5, 10 ℗æm). In addition, the total resistances of semiconductor and metal-semiconductor contact were measured using the transmission line method (TLM).^The linear TLM and the circular TLM were both used to calculate the contact resistance, transfer length, and the specific contact resistance. The results of three kinds of samples, MIG with anneal, MIG without anneal, and non MIG, are presented and compared. The MIG with anneal samples show much lower contact resistance than that of MIG without anneal samples. The quality of the nc-Si and the ohmic contact of the junction are improved after annealing at 700 °C for 2 hours in forming gas (15% H2 and 85% N2).

Download or read book Metal Induced Growth of Si Thin Films and NiSi Nanowires written by and published by . This book was released on 2010 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin film silicon has many useful purposes. Among the applications are solar cells and thin film transistors. This project involves a new and potentially lower cost method to produce thin silicon films. The method is called metal induced growth (MIG). A thin catalyst metal layer deposited on a foreign low cost substrate serves as the basis for growth of a nanocrystalline silicon thin film with thickness of 5-10 microns and preferred orientation of (220). The silicon deposition by magnetron sputtering on the heated substrate resulted in columnar structured grains having a diameter up to about 0.5 microns. Schottky barrier solar cells fabricated on these films gave a photocurrent of about 5 mA/sq cm and open circuit voltage of 0.25 volts. A modified process gave NiSi crystalline nanowires with length up to 10 microns and diameter of about 50 nm.

Download or read book Amorphous and Nanocrystalline Silicon Science and Technology 2004 Volume 808 written by Materials Research Society. Meeting and published by . This book was released on 2004-09-03 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book celebrates 20 years of MRS symposia on the topic of amorphous silicon. Contributors showed that the simplified theories developed to explain the limited experimental information available in the early eighties have spurred more sophisticated experimentation - either refining the early understanding or making it irrelevant. The differences of opinion that continue to exist and emerge are probably the hallmark of the amazing vitality of this field. Applications range from 'mature' thin-film transistors, solar cells and image sensors, to the 'emerging' possibility of erbium-doped nanocrystalline silicon-based materials for lasers and amorphous silicon quantum dots for luminescent devices. The book discusses material characterization, growth processes and devices. Each chapter is further subdivided into sections that group papers around common themes. Topics include: nanomaterials; electronic structure; metastable effects; understanding of growth processes; laser-induced crystallization; metal-induced crystallization; other growth techniques; newer devices; solar cells and thin-film transistors.

Download or read book Fabrication and Analysis of Bottom Gate Nanocrystalline Silicon Thin Film Transistors written by Kyung-Wook Shin and published by . This book was released on 2008 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin film transistors (TFTs) have brought prominent growth in both variety and utility of large area electronics market over the past few decades. Nanocrystalline silicon (nc-Si:H) TFTs have attracted attention recently, due to high-performance and low-cost, as an alternative of amorphous silicon (a-Si:H) and polycrystalline silicon (poly-Si) TFTs. The nc-Si:H TFTs has higher carrier mobility and better device stability than a-Si:H TFTs while lower manufacturing cost than poly-Si TFTs. However, current nc-Si:TFTs have several challenging issues on materials and devices, on which this thesis focuses. In the material study, the gate quality silicon nitride (a-SiNx) films and doped nc-Si:H contacts based on conventional plasma enhanced chemical vapor deposition (PECVD) are investigated. The feasibility of a-SiNx on TFT application is discussed with current-voltage (I-V)/capacitance-voltage(C-V) measurement and Fourier Transform Infrared Spectroscopy (FTIR) results which demonstrate 4.3 MV/cm, relative permittivity of 6.15 and nitrogen rich composition. The doped nc-Si:H for contact layer of TFTs is characterized with Raman Spectroscopy and I-V measurements to reveal 56 % of crystalinity and 0.42 S/cm of dark conductivity. Inverted staggered TFT structure is fabricated for nc-Si:H TFT device research using fully wet etch fabrication process which requires five lithography steps. The process steps are described in detail as well as adaptation of the fabrication process to a backplane fabrication for direct conversion X-ray imagers. The modification of TFT process for backplane fabrication involves two more lithography steps for mushroom electrode formation while other pixel components is incorporated into the five lithography step TFT process. The TFTs are electrically characterized demonstrating 7.22 V of threshold voltage, 0.63 S/decade of subthreshold slope, 0.07 cm2/V-s of field effect mobility, and 106 of on/off ratio. The transfer characteristics of TFTs reveal a severe effect of parasitic resistance which is induced from channel layer itself, a contact between channel layer and doped nc-Si:H contact layer, the resistance of doped nc-Si:H contact layer, and a contact between the doped nc-Si:H layer and source/drain metal electrodes. The parasitic resistance effect is investigated using numerical simulation method by various parasitic resistances, channel length of the TFT, and intrinsic properties of nc-Si:H channel layer. It reveals the parasitic resistance effect become severe when the channel is short and has better quality, therefore, several further research topics on improving contact nc-Si:H quality and process adjustment are required.

Download or read book The Design and Development of Nanocrystalline Silicon Thin Film Transistors written by Jarrod McDonald and published by . This book was released on 2004 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work reports on the fabrication of thin film transistor devices at low temperatures using hydrogenated-nanocrystalline silicon (nc-Si:H). Nanocrystalline silicon is a new electronic material, which is capable of being deposited at low temperatures on any substrate, and thus offers the possibility of making large area devices on flexible substrates. This work presents a design and process for fabricating 25 [mu]m length n-channel, top gate, thin film transistors. The TFTs were fabricated using hydrogenated-nanocrystalline silicon (nc-Si:H), deposited by plasma enhanced chemical vapor deposition (PECVD) over a thermally oxidized silicon wafer. The deposition was done at a temperature of 300°C. Metal layers were deposited by thermal evaporation and etching steps were done via dry etching in a reactive ion etching system and by wet etching. Silicon nitride, deposited by PECVD at 300°C, was used as the dielectric material in the TFT. MIS capacitors were made to judge the quality of the silicon nitride/nc-Si:H interface, and interface defect densities were measured using capacitance-voltage techniques. It was found that an interface defect density of approximately 4.55x1011 cm−1eV−1 was achievable with hydrogen passivation. MIM capacitors were made to determine the dielectric breakdown of the material. The silicon nitride layer broke down at an electric field of 4 MV/cm. The transistors tested have shown a threshold voltage (V[subscript TH])[nearly equal to]13.3 volts, a channel surface mobility (u)[nearly equal to].2 cm2/[V·sec] and an on-off ratio of [nearly equal to]103.

Download or read book Nanocrystalline Silicon Thin Film Transistors written by M. Bauza and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thin Film Transistors Amorphous silicon thin film transistors written by Yue Kuo and published by Kluwer Academic Pub. This book was released on 2004 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first reference on amorphous silicon and polycrystalline silicon thin film transistors that gives a systematic global review of all major topics in the field. These volumes include sections on basic materials and substrates properties, fundamental device physics, critical fabrication processes (structures, a-Si: H, dielectric, metallization, catalytic CVD), and existing and new applications. The chapters are written by leading researchers who have extensive experience with reputed track records. Thin Film Transistors provides practical information on preparing individual functional a-Si: H TFTs and poly-Si TFTs as well as large-area TFT arrays. Also covered are basic theories on the a-Si: H TFT operations and unique material characteristics. Readers are also exposed to a wide range of existing and new applications in industries.

Download or read book Kinetics of Silicide induced Crystallization of Polycrystalline Thin Film Transistors Fabricated from Amorphous Chemical Vapor Deposition Silicon written by Hansuk Kim and published by . This book was released on 1999 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metal Induced Crystallization and Polysilicon Thin Film Transistors written by Bo Zhang and published by . This book was released on 2009-05-01 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nowadays,active-matrix addressing using a-Si TFTs is dominating in the flat panel display markets. However, low temperature polysilicon has been proposed and considered to be a promising alternative technology. Metal induced crystallization (MIe is one of the methods to obtain high quality polysilicon films at low temperatures. A few technologies are presented in this monograph, which improve the quality of MIC polysilicon film and hence the performance of TFTs built on. Amelioration of MIC processes has been made to produce high performance polysilicon TFTs using solution based MIC (SMIe and defined-grain MIC (DG-MIe methods. Novel post-annealing technologies are also introduced to reduce the micro-defects in MIC polysilicon film and hence to achieve better performance. These technologies include YAG laser post-annealing and flash lamp post-annealing. Particularly, it is the first time to report the application of flash lamp annealing technology in the fabrication of low temperature polysilicon and TFTs.

Download or read book Nanocrystalline Silicon Thin film Transistors written by Czang-Ho Lee and published by . This book was released on 2006 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nanocrystalline Silicon Thin Film Transistors written by Durga Prasanna Panda and published by . This book was released on 2006 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, we will describe the growth and properties of p-channel nc-Si thin film transistor (TFT) devices. In contrast to previous work, a significant improvement in the hole mobility was achieved by an innovative approach of depositing nc-Si for the channel material using very high hydrogen dilution and low ion bombardment in a PECVD reactor. The doping of the body was changed by doping with ppm levels of phosphorous, and the threshold voltage was found to change systematically as phosphorus content increased. We were thus able to show that a high-quality nanocrystalline silicon material can be controllably doped in small amounts. The TFT devices are of the bottom-gate type, grown on oxidized Si wafers. Source and drain contacts were provided by using either plasma grown p type nanocrystalline layers, or by the simple process of Al diffusion. A top layer of plasma-deposited silicon dioxide was found to decrease the off current significantly. High ON/OFF current ratios exceeding 106 were obtained. Hole mobilities in the devices were consistently good, with the best mobility being in the range of ∼1.6 cm2/V-s, which is the highest so far to the best of our knowledge.

Download or read book MEMS and Nanotechnology Volume 4 written by Tom Proulx and published by Springer Science & Business Media. This book was released on 2011-05-21 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: MEMS and Nanotechnology, Volume 4 represents one of eight volumes of technical papers presented at the Society for Experimental Mechanics Annual Conference on Experimental and Applied Mechanics, held at Uncasville, Connecticut, June 13-16, 2011. The full set of proceedings also includes volumes on Dynamic Behavior of Materials, Mechanics of Biological Systems and Materials, Mechanics of Time-Dependent Materials and Processes in Conventional and Multifunctional Materials; Optical Measurements, Modeling and, Metrology; Experimental and Applied Mechanics, Thermomechanics and Infra-Red Imaging, and Engineering Applications of Residual Stress.

Download or read book Top gate Nanocrystalline Silicon Thin Film Transistors written by Hyun Jung Lee and published by . This book was released on 2008 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin film transistors (TFTs), the heart of highly functional and ultra-compact active-matrix (AM) backplanes, have driven explosive growth in both the variety and utility of large-area electronics over the past few decades. Nanocrystalline silicon (nc-Si:H) TFTs have recently attracted attention as a high-performance and low-cost alternative to existing amorphous silicon (a-Si:H) and polycrystalline silicon (poly-Si) TFTs, in that they have the strong potentials which a-Si:H (low carrier mobility and poor device stability) and poly-Si (poor device uniformity and high manufacturing cost) counterparts do not have. However, the current nc-Si:H TFTs expose several challenging material and devices issues, on which the dissertation focuses.

Download or read book Formation of Crystalline silicon Islands for Thin film Transistors by Excimer laser induced Lateral Growth written by Paul Christiaan van der Wilt and published by . This book was released on 2003 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thin Film Transistor Technologies written by Yue Kuo and published by The Electrochemical Society. This book was released on 1999 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Low Temperature Metal Induced Laterally Crystallized Polysilicon Thin Film Transistors for AMLCD Applications written by Gururaj A. Bhat and published by . This book was released on 1998 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thin Film Transistor Technologies VI written by Yue Kuo and published by The Electrochemical Society. This book was released on 2003 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: