Millimeter-wave devices

SiC should also be more effective than silicon or gallium arsenide particularly in microwave and millimeter-wave devices and in high-voltage power devices. 

The promising electronic properties of beta-silicon carbide are compared to those of other semiconductor materials in Table 8.3 of Ch. 8. A major advantage of this material is its high-temperature potential (>1000"C) which far surpasses that of other semiconductors. Beta-SiC should also be more effective than silicon or gallium arsenide particularly in microwave and millimeter-wave devices and in high-voltage power devices. The development of SiC as a semiconductor is still in the laboratory state. 

The lack of a capability to screen for explosives hidden on an individual is a major vulnerability in aviation and general security. Personal privacy issues and perceived health risks have deterred the use of bulk detectors, such as X ray, X-ray backscatter, and millimeter wave, for screening of individuals for concealed explosives. Consequently, the TSA is focused on trace detection as the best solution for passenger screening in airports. The TSA has determined that individuals carrying as little as 1 lb of concealed explosives get sufficiently contaminated to be detectable by portal devices that use trace detectors. The level of contamination on an individual s exterior clothing that can be routinely detected by the best portal devices is about 1 pg or about 1 part in 109 of the explosive mass. 

Measurement of device bandwidths in the order of 100 GHz typically requires heterodyne detection and a stripline electrode configuration such as that illustrated in Fig. 31. The response of polymeric electro-optic modulators is typically flat to 100 GHz. Fall off above that frequency (Fig. 32) can be traced to resistive losses in millimeter wave transmission structures and in the metal electrodes. 

LeSurf, J. C. G. (1990). Millimeter-Wave Optics, Devices, and Systems. Hilger, Bristol. LeSurf, J. C. G. (1993). Gaussian Beam Mode Optics for Millimeter-Wave and Terahertz Systems. Int. Soc. Opt. Eng., Bellingham, WA. 

Flexible electronic devices are increasingly capturing the attention of researchers in radio frequency (RF) technologies and metamaterials physics, and are not limited to electronics applications such as light emitting diodes (7). These devices are driven by the pliable, conformal, and stretchable characteristics of elastomeric substrates [7-13], Examples of RF and terahertz devices demonstrated on flexible device platforms include curved antennas [12], millimeter-wave patch flexible antennas and coupled line filters [13], coplanar waveguide antenna [14], stretchable microfluidic RF antenna [15], frequency selective surfaces and metamaterials [8], microwave frequency switches [16], tunable metamaterials [17, 18], and tunable dielectric and magnetic properties [10]. 

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