Browsing by Author "Kao, Chyuan-Haur"

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Optical and electrical characterization of reverse bias luminescence in InGaN light emitting diodes
(2011)
Chen, Hsiang
;
Kao, Chyuan-Haur
;
Lu, Tien-Chang
;
Shei, Shih-Chang
;
光電工程學系
This study investigates the reliability physics of the reverse bias luminescence (RBL) of InGaN/GaN light emitting diodes. Optical and electrical characterization techniques including surface temperature measurements, 2D X-ray fluorescent element analysis, and 2D electroluminescence (EL) measurements reveal the leakage current distribution and the origin of the reverse bias leakage current. Using these techniques, this study examines the electroluminescence behavior and surface temperature distribution in forward bias and reverse bias conditions. Results show that the reverse bias EL originates from hot electron-induced emission, which in turn is due to the leakage current in the high electric field region caused by metal contact abnormalities. The optical and electrical characterization techniques adopted in this study are a promising screening tool for correlating device failures with fabrication processes.
Passivation of yellow luminescence defects in GaN film by annealing and CF(4) plasma treatment
(2011-07-01)
Chen, Hsiang
;
Kao, Chyuan-Haur
;
Chen, Yi-Chen
;
Lo, Hong-Kai
;
Yeh, Yih-Min
In this study, we demonstrated that yellow luminescence (YL) defects can be mitigated with proper annealing or CF(4) plasma treatment. Multiple material analyses, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and surface roughness measurements were performed to investigate improvements in GaN film material properties caused by annealing and CF(4) plasma treatment. Filling vacancies during the annealing process and incorporating fluorine atoms to bond with dangling bonds during the plasma treatment process may lessen YL defects and decrease YL luminescence.
Passivation of yellow luminescence defects in GaN film by annealing and CF4 plasma treatment
(2011-07-01)
Chen, Hsiang
;
Kao, Chyuan-Haur
;
Chen, Yi-Chen
;
Lo, Hong-Kai
;
Yeh, Yih-Min
In this study, we demonstrated that yellow luminescence (YL) defects can be mitigated with proper annealing or CF4 plasma treatment. Multiple material analyses, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and surface roughness measurements were performed to investigate improvements in GaN film material properties caused by annealing and CF4 plasma treatment. Filling vacancies during the annealing process and incorporating fluorine atoms to bond with dangling bonds during the plasma treatment process may lessen YL defects and decrease YL luminescence.
The characteristics of the high-K Er2O3 (erbium oxide) dielectrics deposited on polycrystalline silicon
(2012-03-01)
Kao, Chyuan-Haur
;
Chen, Hsiang
;
Pan, Yu Tsung
;
Chiu, Jing Sing
;
Lu, Tien-Chang
The high-k Er2O3 films deposited on polycrystalline silicon treated with various post-rapid thermal annealing (RTA) temperatures were formed as high k dielectrics. In order to study the annealing effects, electrical measurements, optical characterizations, and multiple material analyses techniques including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) were performed to examine the differences between the samples in various annealing conditions. The annealing temperature at 800 degrees C was the optimal condition to form a well-crystallized Er2O3 film with excellent material quality and electrical properties. RTA annealing at an appropriate annealing temperature of 800 degrees C might effectively mitigate the dangling bonds and traps and improve electrical and material properties of the dielectric. (C) 2012 Elsevier Ltd. All rights reserved.