Table 4.
Comparison between methods for fabricating neural electrodes based on a flexible material.
| Investigators | Type of neural electrode | Insulation material | Method to pattern insulation material | Metal material | Number of recording channels | Size of insertion/implantation site (length × width × thickness) [mm] | Size of recording electrode [μm] | Observation of neural activities |
|---|---|---|---|---|---|---|---|---|
| Rousche et al. (2001) | Intracortical | Probimide 7520 (Arch Chemicals) | Photosensitive | Cr/Au | 3 | 1.5 × 0.16 × 0.02 | 20–40 × 20–40 | Yes |
| Metz et al. (2001) | Microfluid, Intracortical | PI-2732 (DuPont), PI-2611 (DuPont) | Photosensitive, O2 plasma | Ti/Pt | a | a × a × >0.03 | 50–200 × 50–200 | No |
| Stieglitz and Gross (2002) | Intracortical | Pyralin Pi-2611 (HD Microsystems) | Photosensitive, O2 plasma | Ti/Pt, Ti/Au | 5, 10 | 2010 × 0.16 × 0.02, 1950 × 0.26 × 0.02 | 10 (diameter) | No |
| Takahashi et al. (2003) | ECoG | Kapton 100H (Toray DuPont) | Photosensitive, O2 plasma, YAG laser | Cr/Au | 69 | 2.0 × 2.0 × 0.04 | 80 × 80 | Yes |
| Takeuchi et al. (2004) | Intracortical | PIX3400 (HD Microsystems) | O2 plasma, DRIE, XeF2 etching | Ti/Al | 3 | 1.2 × 0.16 × 0.025 | 20 × 20 | Yes |
| Takeuchi et al. (2005) | Microfluid, Intracortical | Parylene (Specialty Coating Systems) | O2 plasma | Au | 1, 6 | a × a × 0.02 | a | Yes |
| Hollenberg et al. (2006) | ECoG | SU-8 (Kapton) | RF plasma, UV light | Ti/Au | 64 | 5.25 × 5.25 × 75 | 150 (diameter) | Yes |
| Cheung et al. (2007) | Intracortical | PI-2611 (HD Microsystems), PI-2610 (HD Microsystems) | O2 plasma | Ti/Pt | 16 | a× 0.035−0.195 × 0.015 | 25 (diameter) | Yes |
| Mercanzini et al. (2008) | Intracortical | PI-2611 (HD Microsystems), PI-2610 (HD Microsystems) | CF4 plasma, O2 plasma | Ti/Pt | 16 | 1.5 × a× 0.019 | 25 (diameter) | Yes |
| Chen et al. (2009) | Intracortical | PI-2611 (HD Microsystems) | O2 plasma | Au | 16 | 1.1 × 0.22 × 0.063 | 32 (diameter) | Yes |
| Rubehn et al. (2009) | ECoG | polyimide U-Varnish S (UBE) | O2 plasma | Pt | 252 | 60 × 35 × 33 | 1000 (diameter) | Yes |
| Myllymaa et al. (2009) | ECoG | Kapton HN film (DuPont), PI-2525 (HD Microsystems), PI-2771 (HD Microsystems) | Photosensitive, scissors and knife | Ti/Pt | 8 | a × a × 0.033 | 200 (diameter) | Yes |
| Our method | ECoG, Intracortical, Guide cannula | Fujifilm Durimide 7510 (Fujifilm) | Photosensitive | Cr/Au | 3, 5, 16 | 4.6 × 2.0 × 0.02, 2.645 × 0.31 × 0.02, 10 × 0.25 × 0.012 | 100 (diameter), 40 (diameter), 100 (diameter) | Yes |
a
Not mentioned.