Browsing by Author "Wang, C."

Now showing 1 - 4 of 4

Multiple sensors applied to monitorland subsidence in Central Taiwan
(2015)
Hung, W-C
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Wang, C.
;
Hwang, C.
;
Chen, Y. -A.
;
Chiu, H. -C.
During 1992-2013, pumping of groundwater caused large-scale aquifer-system compaction and land subsidence in the Choshui River Alluvial Fan (CRAF) in Taiwan. The subsidence has already endangered the operation of Taiwan High Speed Rail (THSR). In this paper, we introduce the multiple sensors monitoring system to study the extent of subsidence in CRAF and its mechanism, including GPS (Global Positioning System), PSI (Persistent Scatterer Interferometry), leveling and multi-layer compaction monitoring well. These sensors complement each other in spatial and temporal resolutions.
Study of Enhancement-Mode Tri-Gate InAs HEMTs for Low Noise Application
(2019-01-01)
Wang, C.
;
Lin, Y. C.
;
Kuo, C. N.
;
Lee, M. W.
;
Yao, J. N.
An enhancement-mode tri-gate InAs HEMT is investigated for low noise application in this paper. The 3-D tri-gate structure is sidewall-gate-metal connected to InAlAs layers, the gate connection to the InAlAs layers increases their potential to the positive direction with increasing the gate bias, resulting gate control ability enhancement. Compared with planar device, the tri-gate device shows high transconductance and low noise figure. The enhancement-mode tri-gate device exhibits excellent low noise figure with less than 3.5 dB when the device operation frequency range of 18 GHz to 50 GHz.
Study of Thick Copper Metallization with WNx as Diffusion Barrier for AlGaN/GaN HEMTs
(2019-01-01)
Lin, Y. C.
;
Lee, M. W.
;
Tsai, M. Y.
;
Wang, C.
;
Yao, J. N.
In this study, the thick copper metallization with WNx as diffusion barrier is investigated for AlGaN/GaN HEMTs. The device current density, transconductance, ft, fmax, noise figure were evaluated for the device with and without thick copper interconnect metal, and the thermal stability test was performed after the device with copper metallization.
Tunable nanoblock lasers and stretching sensors
(2016)
Lu, T. W.
;
Wang, C.
;
Hsiao, C. F.
;
Lee, P. T.
;
光電工程學系
Reconfigurable, reliable, and robust nanolasers with wavelengths tunable in the telecommunication bands are currently being sought after for use as flexible light sources in photonic integrated circuits. Here, we propose and demonstrate tunable nanolasers based on 1D nanoblocks embedded within stretchable polydimethylsiloxane. Our lasers show a large wavelength tunability of 7.65 nm per 1% elongation. Moreover, this tunability is reconfigurable and reliable under repeated stretching/relaxation tests. By applying excessive stretching, wide wavelength tuning over a range of 80 nm (spanning the S, C, and L telecommunication bands) is successfully demonstrated. Furthermore, as a stretching sensor, an enhanced wavelength response to elongation of 9.9 nm per % is obtained via the signal differential from two nanoblock lasers positioned perpendicular to each other. The minimum detectable elongation is as small as 0.056%. Nanoblock lasers can function as reliable tunable light sources in telecommunications and highly sensitive on-chip structural deformation sensors.