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ABSTRACT: A novel fabrication process for a fixed-fixed membrane structure in RF microelectromechanical-systems switches is implemented to alter the stress-distribution and deformation of the membrane and thus vary the required actuation force. This two-step process removes UV-light-exposed photoresist first by wet dissolution of a sacrificial photoresist layer and then by oxygen reactive ion etching. During wet release, the patterned but unexposed photoresist above the membrane helps prevent stiction. Further designs of photoresist-aided membranes are demonstrated to control the measured pull-down voltage level of the switches, which is consistent with the multiphysics simulation work.
Journal of Microelectromechanical Systems 07/2010; · 2.10 Impact Factor
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ABSTRACT: In this paper, a novel multi-port, multi-band small planar antenna is presented. It has three input ports; each of them has their own frequency bands, 2.4 GHz, 3.5 GHz and 5.5 GHz. These three antennas are printed on a small area, 250 mm<sup>2</sup>. The proposed antenna is printed on a cheap organic material substrate with other RF components. It requires enough isolation among the antennas since each frequency band ought to operate at the same time. Polarizations of monopole antennas are all orthogonal as best as possible to minimize mutual couplings and open stubs are used at feed points to block the other frequency band signals. The antenna proposed in this paper is a solution to the onboard configuration of handset system needed multiple wireless services and they can be used simultaneously.
Microwave Conference, 2007. APMC 2007. Asia-Pacific; 01/2008
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ABSTRACT: This paper describes an improved manufacturing technology for the fabrication of radio frequency (RF) microelectromechanical systems switches on a laminated printed circuit board (PCB). The process simplifies the fabrication process without sacrificing the RF performance of switches on the PCB. The proposed process patterns a 17.5-μm-thick copper layer on the PCB; as a result, the surface becomes highly nonplanarized. Polyimide is then used to planarize the PCB's patterned copper layer. The use of polyimide for planarization has not only made the fabrication process simpler, but it has also reduced the formation of voids in the photoresist sacrificial layer where metallic membrane is deposited and patterned. The switches fabricated with this technology demonstrate a low insertion loss (less than 0.06 dB at 10 GHz) and good isolation (less than 20 dB at 10 GHz).
IEEE Sensors Journal 11/2005; · 1.52 Impact Factor
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ABSTRACT: A microstrip antenna with integrated RF microelectromechanical system (MEMS) switches is proposed and demonstrated to operate at dual frequencies with circular polarization. The switches are incorporated into the diagonally fed square patch for controlling the operating frequency and a rectangular stub attached to the edge of the patch acts as the perturbation to produce the circular polarization at 6.69 GHz and 7.06 GHz.
Antennas and Propagation Society International Symposium, 2005 IEEE; 08/2005
