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101.
TFT-LCD技术的研究进展与发展趋势 总被引:2,自引:0,他引:2
介绍了近年来世界TFT LCD技术的研究现状,论述了未来TFT LCD技术的发展趋势 相似文献
102.
We report on the effects of back channel etch depth and etchant chemistry on the electrical characteristics of inverted staggered advanced amorphous silicon thin-film transistors. We found that the optimum amorphous silicon film thickness in the channel is about 800-1100 Å. Three dry etch, HBr + Cl2, C2F6, and CCl2F2 + O2, and one wet etch, KOH, chemistries are used for the back channel etch processing. We established that dry etch can be used for the back channel etch of amorphous silicon transistor without degrading its electrical characteristics. 相似文献
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Paul Sonntag Jan Haschke Sven Kühnapfel Tim Frijnts Daniel Amkreutz Bernd Rech 《Progress in Photovoltaics: Research and Applications》2016,24(5):716-724
We present an interdigitated back‐contact silicon heterojunction system designed for liquid‐phase crystallized thin‐film (~10 µm) silicon on glass. The preparation of the interdigitated emitter (a‐Si:H(p)) and absorber (a‐Si:H(n)) contact layers relies on the etch selectivity of doped amorphous silicon layers in alkaline solutions. The etch rates of a‐Si:H(n) and a‐Si:H(p) in 0.6% NaOH were determined and interdigitated back‐contact silicon heterojunction solar cells with two different metallizations, namely Al and ITO/Ag electrodes, were evaluated regarding electrical and optical properties. An additional random pyramid texture on the back side provides short‐circuit current density (jSC) of up to 30.3 mA/cm2 using the ITO/Ag metallization. The maximum efficiency of 10.5% is mainly limited by a low of fill factor of 57%. However, the high jSC, as well as VOC values of 633 mV and pseudo‐fill factors of 77%, underline the high potential of this approach. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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CHEN Qian XIE Yi CHEN Gong-jing ZHANG Wei 《半导体光子学与技术》2006,12(3):158-162,172
A new method to determine the optical constant and thickness of thin films is proposed. Based on the Fresnel's optical expression, the improved flexible tolerance method(FTM) is employed in the case of a digital model of thin film to fit the curve of measured reflectance spectrum. The simulation results show a satisfactory correlation of the optical constant with the thickness of the target film. By taking the influence of nonlinear condition into account as well as more direct and indirect limitation, the precision and value-searching efficiency have been improved. Furthermore, the problem of dimension degradation, which exists in “Downhill Simplex”, has been successfully avoided. No initial input is needed for the procedure of optimization to achieve optical solution, which makes the whole processing of value calculation much more convenient and efficient. 相似文献
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Dong-Soo Yoon Hong Koo Baik Sung-Man Lee Jae Sung Roh 《Journal of Electronic Materials》2001,30(5):493-502
The effects of the amount of RuO2 added in the Ta film on the electrical properties of a Ta-RuO2 diffusion barrier were investigated using n++-poly-Si substrate at a temperature range of 650–800°C. For the Ta layer prepared without RuO2 addition, Ta2O5 phase formed after annealing at 650°C by reaction between Ta and external oxygen, leading to a higher total resistance and
a non-linear I-V curve. Meanwhile, in the case of the Ta film being deposited with RuO2 incorporation, not only a lower total resistance and ohmic characteristics exhibited, but also the bottom electrode structure
was retained up to 800°C, attributing to the formation of a conductive RuO2 crystalline phase in the barrier film by reaction with the indiffused oxygen because of a Ta amorphous structure formed by
chemially strong Ta-O or Ta-Ru-O bonds and a large amount of conductive RuO2 added. Since a kinetic barrier for nucleation in formation of the crystalline Ta2O5 phase from an amorphous Ta(O) phase is much higher than that of crystalline RuO2 phase from nanocrystalline RuOx phase, the formation of the RuO2 phase by reaction between the indiffused oxygen and the RuOx nanocrystallites is kinetically more favorable than that of Ta2O5 phase. 相似文献
110.
《Organic Electronics》2014,15(7):1672-1677
In this paper organic thin film transistors (OTFTs) are directly fabricated on fabric substrates consisting of Polyethylene Terephthalate (PET) fibers. A key process is coating the polymer layers on the fabric in order to reduce the large surface roughness of the fabric substrate. Two polymers, i.e. polyurethane (PU) and photo-acryl (PA), are used to reduce the large surface roughness and simultaneously improve the process compatibility of the layers with the subsequent OTFTs processes while also retaining the original flexibility of the fabric. The surface roughness of the PU/PA-coated fabric is significantly reduced to 0.3 μm. Furthermore, the original flexibility of the PET fabric remained after coating of the PU/PA polymer layers. The mobility of the OTFTs fabricated on the PU-PA coated fabric substrate is 0.05 ± 0.02 cm2/V s when three PA layers and 90 nm thick pentacene layer were used. The performance does not vary even after 30,000 bending test. 相似文献