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

2. Types of Resonators fabricated
Two types of Split-Ring Resonators (SRRs) were used for fabrication of metamaterials
square shaped SRR circular shaped SRR
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3. Typical lift-off procedure used in fabrication of LHM structures
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4. 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
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Samples fabricated
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6. 10 GHz Sample on textolite
10 GHz Sample on Silicon
10 GHz Sample on textolite
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7. DALHM - First Year Meeting
10 GHz Sample on glass
30 GHz Samples
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8. 30 GHz in-plane LHM structures
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9. 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
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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
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Future developments
Etching technology will be fully developed
Structures with the gap of each SRR filled with semiconductor will be fabricated ?
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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
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