Browsing by Author "Lu, Jin"

Now showing 1 - 6 of 6

A low-temperature method for improving the performance of sputter-deposited ZnO thin-film transistors with supercritical fluid
(2009-04-20)
Chen, Min-Chen
;
Chang, Ting-Chang
;
Huang, Sheng-Yao
;
Chang, Kuan-Chang
;
Li, Hung-Wei
A low-temperature method, supercritical CO(2) (SCCO(2)) fluid technology, is employed to improve the device properties of ZnO TFT at 150 degrees C. In this work, the undoped ZnO films were deposited by sputter at room temperature and treated by SCCO(2) fluid which is mixed with 5 ml pure H(2)O. After SCCO(2) treatment, the on/off current ratios and threshold voltage of the device were improved significantly. From x-ray photoelectron spectroscopy analyses, the enhancements were attributed to the stronger Zn-O bonds, the hydrogen-related donors, and the reduction in dangling bonds at the grain boundary by OH passivation.
Anomalous Capacitance Induced by GIDL in P-Channel LTPS TFTs
(2009-11-01)
Lin, Chia-Sheng
;
Chen, Ying-Chung
;
Chang, Ting-Chang
;
Chen, Shih-Ching
;
Jian, Fu-Yen
In this letter, a mechanism of anomalous capacitance in p-channel low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs) was investigated. In general, the effective capacitance was only the overlap region and independent with the frequency in LTPS TFTs under the OFF state. However, our experimental results reveal that the capacitance was related with the leakage current and that it was dependent with the measurement frequencies when operated at the OFF-state region. The increase of the capacitance value is verified to be due to the increase of the electron capacitance originating from a gate-induced drain-leakage (GIDL) one. Nevertheless, the GIDL-induced electron capacitance can be suppressed by employing band-to-band hot electron stress.
Bias-induced oxygen adsorption in zinc tin oxide thin film transistors under dynamic stress
(2010-06-28)
Chen, Yu-Chun
;
Chang, Ting-Chang
;
Li, Hung-Wei
;
Chen, Shih-Ching
;
Lu, Jin
This study investigates the effects of bias-induced oxygen adsorption on the electrical characteristic instability of zinc tin oxide thin film transistors in different ambient oxygen partial pressures. When oxygen pressure is largest, the threshold voltages showed the quickest increase but the slowest recovery during the stress phase and recovery phase, respectively. This finding corresponds to the charge trapping time constant and recovery time constant, which are extracted by fitting the stretched-exponential equation and which exhibit a relationship with oxygen pressure. We suggest that the gate bias reduces the activation energy of oxygen adsorption during gate bias stress. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3457996]
High-stability oxygen sensor based on amorphous zinc tin oxide thin film transistor
(2012-06-25)
Chen, Yu-Chun
;
Chang, Ting-Chang
;
Li, Hung-Wei
;
Chung, Wan-Fang
;
Wu, Chang-Pei
This research presents a sol-gel derived zinc tin oxide thin film transistor (TFT) as a high-stability oxygen sensor. Due to its high sensitivity, oxygen has been traditionally regarded as having a negative influence on the electrical characteristics of zinc-based TFTs; however, TFTs can also act as an oxygen sensor. After illumination with visible light in oxygen-rich ambient, a significant increase in drain current of nearly 10 4 times occurs with fixed gate and drain voltages. It is expected that an optimized method of illumination can help to reset the electrical characteristics or distinguish the on/off state of this reliable oxygen sensor. (C) 2012 American Institute of Physics. [ http://dx.doi.org/10.1063/1.4731773]
Improvement of the performance of ZnO TFTs by low-temperature supercritical fluid technology treatment
(2009-12-25)
Chen, Min-Chen
;
Chang, Ting-Chang
;
Huang, Sheng-Yao
;
Chang, Kuan-Chang
;
Huang, Hui-Chun
in this paper, the supercritical CO(2) (SCCO(2)) fluid technology is successfully applied to improve the electrical characteristics of sputtered ZnO TFTs at low temperature (150 degrees C). After the treatment of SCCO(2) fluids mixed with water, the ZnO TFT exhibited superior transfer characteristics and lower threshold voltage. According to X-ray photoelectron spectroscopy (XPS) analyses, the improvements were attributed to the increase of binding energies of Zn-O bonds, hydrogen-related donors and the reduction of traps at the grain boundaries in ZnO thin films. In addition, the crystalline quality and microstructure of ZnO thin films were also investigated by using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The transmittance of the ZnO film was measured by an N&K analyzer 1280 (N&K Technology, Inc.), which is a new type of thin-film measurement system. (C) 2009 Elsevier B.V. All rights reserved.
Temperature-Dependent Biaxial Compressive Strain Effect on p-MOSFETs
(2009)
Kuo, Yuan-Jui
;
Chang, Ting-Chang
;
Dai, Chin-Hao
;
Chen, Shih-Ching
;
Lu, Jin
The influence of biaxial compressive stress on p-type metal-oxide-semiconductor field-effect transistors (MOSFETs) was investigated. It was found that drain current and hole mobility of p-type MOSFET with Si(1-x)Ge(x) raised source/drain and external applied mechanical stress significantly decreased due to the increase of effective conductive mass at room temperature. However, this phenomenon was inverted above 333 K. Because the hole can gain enough thermal energy to transmit to a higher energy level by intervalley scattering, its transport mechanism was dominated by lower effective mass at higher energy level.