Metamaterials Fabrication D. Cengher, M. Gokkavas, M. Sfendourakis and G. Constantinidis Microelectronics Research Group, IESL - FORTH

Types of Resonators fabricated Two types of Split-Ring Resonators (SRRs) were used for fabrication of metamaterials square shaped SRR circular shaped SRR DALHM - First Year Meeting

Typical lift-off procedure used in fabrication of LHM structures DALHM - First Year Meeting

Processing steps for fabrication of metamaterials Deposition of alignment marks on the wafer (for 4 inch silicon wafers) Wafer cleaning Wafer coating with photoresist by spinning. Typically, the photoresist used is AZ 5214, but we have used also the photoresist AZ 4562 Soft-baking of the photoresist UV exposure of the photoresist using a Karl Suss MA6/BA6 maskaligner Second UV exposure necessary if we use image reversal procedure Treatment of the AZ 5214 photoresist in Clorobenzene Developing of the pattern using AZ 400K photoresist developer Deposition of 1 m thick silver/copper layer in a TEMESCAL UHV e-gun evaporator Lift-off of the unnecessary metal in acetone or wet etching DALHM - First Year Meeting

DALHM - First Year Meeting Samples fabricated DALHM - First Year Meeting

10 GHz Sample on textolite 10 GHz Sample on Silicon 10 GHz Sample on textolite DALHM - First Year Meeting

DALHM - First Year Meeting 10 GHz Sample on glass 30 GHz Samples DALHM - First Year Meeting

30 GHz in-plane LHM structures DALHM - First Year Meeting

Multistacking of 1D LHM structures 12 layers polyamide - Ti metallic mesh was fabricated polyamide layers with thickness from 1 μm to 10 μm were obtained to allow fabrication of stacks with different distances between metallic meshes DALHM - First Year Meeting

DALHM - First Year Meeting Dicing of LHM periods Reactive Ion Etching of silicon using SF6 Lapping of silicon samples to 40 μm Wet etching of GaAs Two step wet etching Lapping of GaAs wafers to 300 μm DALHM - First Year Meeting

DALHM - First Year Meeting Future developments Etching technology will be fully developed Structures with the gap of each SRR filled with semiconductor will be fabricated ? DALHM - First Year Meeting

DALHM - First Year Meeting Conclusions Different substrates were used for fabrication of metamaterials from silicon or GaAs to glass or polyethylene foil without major technological problems we have adapted our equipment for the requirements of fabrication of metamaterials the only “problem” is the number of separate samples necessary because our equipment is not adapted for small scale production DALHM - First Year Meeting