-
[show abstract]
[hide abstract]
ABSTRACT: Background
Many chemical agents used in liquid crystal display (LCD) manufacturing have been evaluated in animal studies of female reproductive toxicity. Knowledge of their reproductive toxicity in humans is scant.AimsTo determine the effect of organic solvents on menstrual cycle characteristics of workers in LCD manufacturing.Methods
Cross-sectional study of female premenopausal workers in an LCD plant in Taiwan. Menstrual cycle characteristics were assessed from self-administered questionnaires, and chemical exposure was assessed using hand-held volatile organic compound (VOC) monitors with 24h canister sampling.ResultsThere was a response rate of 94%, and the final study population after exclusions was 288. Canister sampling found many chemical compounds with potential reproductive effects in the fabrication areas of the plant. Concentrations of total VOC were higher in the panel and module fabrication areas than in other areas of the plant. The prevalence of short menstrual cycles (>24 days) was higher in panel workers (adjusted odds ratio [OR]: 7.68; 95% confidence interval [CI]: 1.51-39.15) and module workers (adjusted OR: 8.38; 95% CI: 1.72-40.95) than in array fabrication workers and office workers.Conclusions
We found evidence for a possible link between repeated exposure to multiple organic solvents such as ethanol and acetone and increased prevalence of short menstrual cycles in premenopausal women.
Occupational Medicine 09/2012; · 1.14 Impact Factor
-
Microelectronics Journal. 01/2006; 37:328-331.
-
[show abstract]
[hide abstract]
ABSTRACT: InGaN metal-semiconductor-metal photodetectors (MSM-PDs) with recessed electrodes were fabricated. Compared with the conventional planar MSM-PD, it was found that measured photocurrent and photocurrent-to-dark-current contrast ratio were both much larger for the MSM-PD with the recessed electrodes. With a 5-V applied bias and an incident light wavelength of 470 nm, it was found that measured responsivities were 0.144 and 0.038 A/W for the MSM-PDs with and without the recessed electrodes, respectively.
IEEE Photonics Technology Letters 05/2005; · 2.19 Impact Factor
-
IEEE Photonics Technology Letters 03/2005; 17:875-877. · 2.19 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: AlGaN/GaN metal–semiconductor–metal (MSM) ultraviolet (UV) photodetectors with photo-chemical vapour deposition (photo-CVD) annealed Ni/Au semi-transparent contacts were fabricated. It was found that the transmittances of Ni/Au films increased while the photodetector dark currents became significantly lower after annealing. With a 5 V applied bias, it was found that the photocurrent to dark current contrast ratio and the maximum responsivity were 2.3 × 104 and 0.166 A W−1 for photodetector photo-CVD annealed at 550 °C.
Semiconductor Science and Technology 10/2004; 19(12):1354. · 1.72 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Nitride-based light-emitting diodes (LEDs) with Mg-doped In<sub>0.23</sub>Ga<sub>0.77</sub>N capping layers were successfully fabricated. Compared to Mg-doped GaN layers, it was found that we could achieve a much larger hole concentration from Mg-doped In<sub>0.23</sub>Ga<sub>0.77</sub>N layers. It was also found that we could reduce the 20 mA operation voltage from 3.78 to 3.37 V by introducing a 5-nm-thick In<sub>0.23</sub>Ga<sub>0.77</sub>N layer on top of the p-GaN layer. Furthermore, it was found that output intensity of LEDs with In<sub>0.23</sub>Ga<sub>0.77</sub>N capping layer was much larger, particularly at elevated temperatures.
IEEE Transactions on Electron Devices 01/2004; · 2.32 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In this paper, a InGaN/GaN multiple quantum well structure commonly used for light emitting diodes has been employed for dual functions of optoelectronics devices exhibiting photodetector properties in reverse bias, while at the same time preserving the distinct identities of LED in forward bias. The turn on voltage in forward bias and the breakdown voltage in reverse bias were about 3.2 V and −30 V, respectively. The higher photo- and dark-current densities were detected for larger size of devices. The contrast ratio calculated between photo- and dark-current densities of large-size device decreases more rapidly as compared to that of a small-size device. Thus, one can easily integrate photodetectors with LEDs using the same epi-structure to realize a GaN-based optoelectronic integrated circuit (OEIC).
Solid-State Electronics. 49(8):1347-1351.
-
[show abstract]
[hide abstract]
ABSTRACT: The undoped GaN (u-GaN) and two-dimensional electron gas (2DEG) metal–semiconductor–metal (MSM) photodetectors with semi-transparent Ni/Au Schottky barrier contact electrodes were fabricated. It was found that we could achieve a larger Ni/Au transmittance, higher Schottky barrier heights and larger photocurrent to dark current contrast ratios by photo-chemical annealing of these photodetectors in O2. It was also found that the maximum quantum efficiencies were 13% and 57% for the photo-chemical annealing u-GaN and 2DEG photodetectors, respectively. Furthermore, it was found that we could achieve a larger responsivity, a lower noise level and a larger detectivity by using the 2DEG structure.
Solid-State Electronics.
