Process and realization of a three-dimensional gold electroplated antenna on a flexible epoxy film for wireless micromotion system

The process and realization of a light and low resistive antenna for wireless communications by inductive coupling at 13.56 MHz is presented. The antenna is realized on an insulated substrate made of SU-8 resist in order to prevent the losses due to eddy currents from occurring and to strongly decrease its weight. The conductor is obtained by electroplating 24 μm of gold in a mold of AZ-4562 resist. A Q factor of 29 has been obtained with a maximum of 37 at 19 MHz, for antenna dimensions of 1.5×1.5 cm2. This antenna is the key component for a wireless power supplied microrobot.

[1]  J.A. Von Arx,et al.  On-chip coils with integrated cores for remote inductive powering of integrated microsystems , 1997, Proceedings of International Solid State Sensors and Actuators Conference (Transducers '97).

[2]  Bernd Loechel Thick-layer resists for surface micromachining , 2000 .

[3]  Jane M. Shaw,et al.  Micromachining applications of a high resolution ultrathick photoresist , 1995 .

[4]  On-chip spiral inductors with patterned ground shields for Si-based RF ICs , 1998 .

[5]  K.-L. Krieger,et al.  A new passive CMOS telemetry chip to receive power and transmit data for a wide range of sensor applications , 1997, Proceedings of International Solid State Sensors and Actuators Conference (Transducers '97).

[6]  M. Mehregany,et al.  High-aspect-ratio photolithography for MEMS applications , 1995 .

[7]  Robert Puers,et al.  Electrodeposited copper inductors for intraocular pressure telemetry , 2000 .

[8]  F. Rudolf,et al.  Electrodeposition of 3D microstructures on silicon , 1993 .

[9]  Didier Lippens,et al.  Terahertz time-domain spectroscopy of films fabricated from SU-8 , 1999 .

[10]  Peter Vettiger,et al.  High-aspect-ratio, ultrathick, negative-tone near-UV photoresist and its applications for MEMS , 1998 .

[11]  N. D. Rooij,et al.  High aspect ratio UV photolithography for electroplated structures , 1999 .

[12]  Göran Stemme,et al.  A robust micro conveyer realized by arrayed polyimide joint actuators1A robust micro conveyer realiz , 2000 .

[13]  Herbert Reichl,et al.  High depth to width aspect ratios in thick positive photoresist layers using near UV lithography , 1992 .

[14]  Hiroyuki Fujita,et al.  Fabrication and operation of polyimide bimorph actuators for a ciliary motion system , 1993 .

[15]  Tayfun Akin,et al.  A wireless implantable multichannel digital neural recording system for a micromachined sieve electrode , 1998, IEEE J. Solid State Circuits.

[16]  W. Liu,et al.  A neuro-stimulus chip with telemetry unit for retinal prosthetic device , 2000, IEEE Journal of Solid-State Circuits.