Browsing by Author "Chen, HP"

Now showing 1 - 6 of 6

Barrier characteristics of PECVD alpha-SiC : H dielectrics
(2001)
Chiang, CC
;
Wu, ZC
;
Wu, WH
;
Chen, MC
;
Ko, CC
This work investigates the thermal stability and barrier characteristics of three species of PECVD alpha-SiC:H dielectric films with dielectric constants between 3.5 and 5.4. It is found that the dielectric constant decreases with increasing content of carbon in the alpha-SiC:H film. All of the three specie's of alpha-SiC:H films are thermally stable at temperatures of up to 500degreesC. However, degraded barrier capability and moisture resistance were observed for the alpha-SiC:H film with a k value around 3.5, which has a C/Si atomic ratio of 0.875. This is presumably attributed to poorly crosslinked molecular structure and porosity enhancement by the abundant amount of carbon in the alpha-SiC:H film.
Development of a feedforward active noise control system by using the H-2 and H infinity model matching principle
(1997-03-27)
Bai, MR
;
Chen, HP
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
Two novel active noise control techniques on the basis of feedforward H-2 and H-infinity optimal model matching principle are proposed. These methods effectively overcome the problem of unstable inverse plant resulting from the inherent non-minimum phase property of the cancellation path. The proposed algorithms are implemented by using a digital signal processor. The experimental results obtained by using H-2 and H-infinity feedforward techniques show attenuation for stationary noise in a duct as comparable to those of conventional methods. The proposed methods also have potential in suppressing transient noises that have been the major difficulty in adaptive methods. Comparisons of the methods are summarized. (C) 1997 Academic Press Limited.
Development of a feedforward active noise control system by using the H-2 and H infinity model matching principle
(1997-03-27)
Bai, MR
;
Chen, HP
;
機械工程學系
;
Department of Mechanical Engineering
Two novel active noise control techniques on the basis of feedforward H-2 and H-infinity optimal model matching principle are proposed. These methods effectively overcome the problem of unstable inverse plant resulting from the inherent non-minimum phase property of the cancellation path. The proposed algorithms are implemented by using a digital signal processor. The experimental results obtained by using H-2 and H-infinity feedforward techniques show attenuation for stationary noise in a duct as comparable to those of conventional methods. The proposed methods also have potential in suppressing transient noises that have been the major difficulty in adaptive methods. Comparisons of the methods are summarized. (C) 1997 Academic Press Limited.
Enhanced luminescent and electrical properties of hydrogen-plasma ZnO nanorods grown on wafer-scale flexible substrates
(2005-05-02)
Lin, CC
;
Chen, HP
;
Liao, HC
;
Chen, SY
;
材料科學與工程學系
Photoelectronic characteristics are performed in well-aligned hydrogen-plasma ZnO nanorods grown on 4 in. flexible organic substrates buffered with ZnO film. Enhancement of photoluminescence (PL) properties due to H-2 plasma treatment by a factor of 60 times for relative intensity ratio (ultraviolet emission to deep level emission) has been observed. X-ray photoelectron spectroscopy analysis reveals that the enhanced PL property is attributed to both defect passivation and modification on the surface region of ZnO nanorods due to the absorption of hydrogen ions. However, the PL spectra of H-2 plasma ZnO nanorods can be restored to the original state of ZnO nanorods by thermal annealing process. The current-voltage measurements suggest that the n-type ZnO nanorods with H-2 plasma treatment present a higher conductivity of about 5-6 orders of magnitude than the nonplasma ZnO nanorods. (c) 2005 American Institute of Physics.
Physical and barrier properties of plasma enhanced chemical vapor deposition alpha-SiC : N : H films
(2003-07-01)
Chiang, CC
;
Wu, ZC
;
Wu, WH
;
Chen, MC
;
Ko, CC
In this work, we investigate the thermal stability and physical and barrier properties of three species of plasma enhanced chemical vapor deposition (PECVD) alpha-SiC:N:H silicon carbide films with different carbon and nitrogen contents and dielectric constants less than a value of 5.5. For comparison, one species of alpha-SiN:H film with a k value of 7.2 is also studied. It is found that the dielectric constant decreases with increasing content of carbon and decreasing content of nitrogen in the alpha-SiC:N:H film. All of the three species of alpha-SiC:N:H and the one species of alpha-SiN:H films are thermally stable at temperatures up to 500degreesC. However, degraded barrier capability and moisture resistance were observed for the alpha-SiC:N:H film with a k value of 3.5, which has a C/Si atomic ratio of 0.875. This is presumably due to the poorly crosslinked molecular structure and porosity enhancement caused by the abundant amount of carbon in the alphaSiC:N:H film.
Synthesis and optoelectronic properties of arrayed p-type ZnO nanorods grown on ZnO film/Si wafer in aqueous solutions
(2005-03-07)
Lin, CC
;
Chen, HP
;
Chen, SY
;
材料科學與工程學系
;
Department of Materials Science and Engineering
Highly arrayed nitrogen-doped ZnO nanorods were fabricated on Si buffered with ZnO film by combining wet-chemical process with post-treated by NH3 plasma. The X-ray photoelectron spectroscopy measurement demonstrates that the nitrogen-doped ZnO nanorods have been formed due to nitrogen diffusion through surface adsorption or defect routes. The photoluminescence spectra indicate that a strong UV emission peak around 3.31 eV with negligible deep level emission can be obtained for the nitrogen-doped ZnO nanorods compared to that of the untreated sample. The I-V measurements indicate that the p-type ZnO nanorods with a smaller threshold voltage of 1.5 V can be obtained. (C) 2005 Elsevier B.V. All rights reserved.