Laser micropen integrated direct writing for fabrication of thick film gap-tuning capacitor

• Published in: Microelectronic engineering Vol. 114; pp. 7 - 11
• Main Authors: Cao, Yu, Zeng, Xiaoyan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.02.2014; Elsevier
• Subjects: Applied sciences; Arrays; Capacitors; Cross-disciplinary physics: materials science; rheology; Dielectric, amorphous and glass solid devices; Direct write; Electrodes; Electronics; Exact sciences and technology; Gap-tuning capacitor; Glasses (including metallic glasses); Gold; Laser; Lasers; Materials science; Microelectronic fabrication (materials and surfaces technology); Micropen; Parallel plates; Paste; Physics; Polyimide; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Specific materials; Thick films; Tuning; Gap-tuning capacitor; Polyimide; Micropen; Paste; Direct write; Laser; Energy consumption; Glass; IV-VI compound; Implementation; Parallel plate capacitor; Energy gap; Microelectronic fabrication; Thick film; Electric power consumption; Direct writing; Sacrificial layer; Electrostatic force; Gold; Multilayer coating; Q factor; Capacitive transducer; Colloid; Array; Silicon oxides; High efficiency; Maskless lithography
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2013.08.019

•Thick film gap-tuning capacitors are fabricated by a new method of laser micropen integrated direct writing.•Gold and polyimide are used as the materials of structural and sacrificial layers, respectively.•The maximum tuning range (MTR) of the gap-tuning capacitor is 30.35% with the practical pull-in voltage of 39V.•The process enables a practical route to a desktop fabrication system for electronic circuitry of RF MEMS. With a fixed base-electrode and a movable upper-electrode structure, the electrostatic actuated parallel plate tuning capacitors have the advantages of no DC power consumption, high efficiency and easy to implement. We propose a novel approach of laser micropen integrated direct writing for fabrication of the thick film electrostatic-controlled gap-tuning capacitors. Adopting commercial gold paste (Au) as the material of structural electrodes and polyimide colloid as the material of sacrificial layer, the thick film gap-tuning capacitor arrays are successfully fabricated on the fused silica glass substrate. The electrical analysis shows that the maximum tuning range (MTR) of the thick film gap-tuning capacitor is 30.35% with the practical pull-in voltage of 39V, and the Q value is 50 under the frequency of 1GHz.