AbstractThis paper reports in situ measurement of Young’s modulus and residual stress of electroless nickel films through the use of microfabricated nickel test structures, including electrostatic microactuators and passive devices. The test structures are fabricated in a new surface micromachining process, termed “nickel surface micromachining”, using electroless plated nickel as the structural layer and polysilicon as the sacrificial layer. Subsequent to fabrication, lateral resonant-type electrostatic microactuators of different geometries are resonated by electrical excitation. Using the measured resonant frequencies and knowledge of the device geometry, the Young’s modulus of the film is determined. The passive electroless nickel microstructures deform upon completion of the fabrication process due to residual stress in the film. Measurement of this deformation in conjunction with an appropriate mechanical model is used to determine the residual stress in the films.
In this paper, a novel RF MEMS switch driven by combs with low insertion loss is presented. The developed SPST RF MEMS switch with a lateral resistive contact and gold structure layer on a silicon substrate has been fabricated by surface micromachining process. The RF performance of the switch indicates an insertion loss below 0.30 dB at 20 GHz, a return loss better than 20 dB and isolation greater than 30 dB. Good RF characteristics have been achieved by the large contact area and a lateral Au-to-Au resistive contact.
In this paper we have designed and analyzed shunt capacitive fixed-fixed RF MEMS switch to maintain low actuation voltage. The pull - in voltage of the proposed switch is 7.7V for 2 um air gap. The electromagnetic analysis for the designed structure is, return loss is -23dB in the range of 1-40 GHz, insertion loss is -0.04dB at a frequency range of 1-40 GHz and isolation is - 38.5dB obtained at a frequency of 23.5 GHz. Mechanical analysis for the designed structure is also performed using FEM tool.
Simple and Robust Air Gap-Based MEMS Switch Technology for RF-Applications