Browsing by Author "Juang, Miin-Horng"

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Formation of thin-film transistors with a polycrystalline hetero-structure channel layer
(2008-08-01)
Juang, Miin-Horng
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Tsai, I-Shen
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Jang, S-L
;
Cheng, H. C.
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電子工程學系及電子研究所
A thin-film transistor (TFT) with a polycrystalline Si/SiC hetero-structure channel layer has been proposed. For the conventional polycrystalline silicon (poly-Si) channel layer, the leakage current would be considerably increased with increase of the negative gate bias voltage. However, when a polycrystalline Si/SiC stacked channel layer is employed, the leakage current exhibits just a slight increase with increase of the negative gate bias voltage. As a result, the leakage current can be largely suppressed to a low level without degrading the on-state current. Moreover, when the channel length is further scaled down to 1 mu m and the gate oxide is reduced to 60 nm thickness, the conventional poly-Si TFT device shows even more obvious deterioration of the leakage current. Instead, for the TFT device with a polycrystalline Si/SiC channel layer, no considerable degradation of the leakage characteristics is caused.
pH-Sensing Characteristics of Hydrothermal Al-Doped ZnO Nanostructures
(2013)
Wang, Jyh-Liang
;
Yang, Po-Yu
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Hsieh, Tsang-Yen
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Hwang, Chuan-Chou
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Juang, Miin-Horng
Highly sensitive and stable pH-sensing properties of an extended-gate field-effect transistor (EGFET) based on the aluminumdoped ZnO (AZO) nanostructures have been demonstrated. The AZO nanostructures with different Al concentrations were synthesized on AZO/glass substrate via a simple hydrothermal growth method at 85 degrees C. The AZO sensing nanostructures were connected with the metal-oxide-semiconductor field-effect transistor (MOSFET). Afterwards, the current-voltage (I-V) characteristics and the sensing properties of the pH-EGFET sensors were obtained in different buffer solutions, respectively. As a result, the pH-sensing characteristics of AZO nanostructured pH-EGFET sensors with Al dosage of 3 at.% can exhibit the higher sensitivity of 57.95mV/pH, the larger linearity of 0.9998, the smaller deviation of 0.023 in linearity, the lower drift rate of 1.27mV/hour, and the lower threshold voltage of 1.32V with a wider sensing range (pH 1 similar to pH 13). Hence, the outstanding stability and durability of AZO nanostructured ionic EGFET sensors are attractive for the electrochemical application of flexible and disposable biosensor.
Study of ultra-shallow p(+)n junctions formed by excimer laser annealing
(2010-09-01)
Juang, Miin-Horng
;
Lu, C. N.
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Jang, S. L.
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Cheng, H. C.
;
電子工程學系及電子研究所
Excellent ultra-shallow p(+)n junctions have been formed by thermally treating the BF(2)(+)-implanted Si samples by excimer laser annealing (ELA) at 300-400 rnJ cm(-2) with post low-temperature long-time furnace annealing (FA) at 600 degrees C. A junction with a leakage current density lower than 20 nA cm(-2) and a sheet resistance smaller than 200 Omega square(-1) can be well achieved. No considerable dopant diffusion is observed by using this low-thermal-budget annealing process. However, by simply using the ELA treatment at 300-400 mJ cm(-2), the resultant junction shows a leakage current density as high as 10(4) nA cm(-2) and a peripheral leakage current density of 10(3) nA cm(-1). The large junction leakage is primarily due to the leakage current generated within the junction region near the local-oxidation-of-silicon (LOCOS) edge, and which is substantially caused by the ELA treatment. The large peripheral junction leakage current density can be significantly reduced to be about 0.2 nA cm(-1) after a post low-temperature FA treatment at 600 degrees C. As a result, the scheme that employs ELA treatment with post low-temperature FA treatment would be efficient for forming excellent ultra-shallow p(+)n junctions at low thermal budget. (C) 2010 Elsevier BM. All rights reserved.
Zinc oxide thin-film transistors fabricated via low-temperature hydrothermal method
(2013-09-01)
Wang, Jyh-Liang
;
Yang, Po-Yu
;
Juang, Miin-Horng
;
Hsieh, Tsang-Yen
;
Hwang, Chuan-Chou
Transparent high-performance ZnO TFTs have been fabricated via low-temperature hydrothermal method. The dip of H3PO4 solution prior to the hydrothermal process can form the under-cut AZO seed layer and benefit for the control of ZnO growth. While the use of under-cut AZO seed layer with proper design of channel length, the lateral ZnO growth can be artificially controlled in the desired location to make a continuous active-layer and nearly single one vertical grain boundary cross to the current flow in the channel region. ZnO TFTs indicate the behavior of n-channel enhancement-mode devices. The optimum design of channel length (i.e. L=10 mu m) can provide enough space for the lateral growth of large ZnO grains with less channel defects and bring about the advanced device characteristics (i.e. the positive threshold voltage of 3.0 V, mobility of 9.03 cm(2)/V.s, on/off current ratio >10(6), gate leakage of <1 nA with less fluctuation, and extremely high drain current >500 mu A). (C) 2012 Elsevier B.V. All rights reserved.