Table 2.
Summary of nano and micro fabrication methods
| Fabrication method | Structure dimensions | Advantages | Disadvantage | References | |
|---|---|---|---|---|---|
| NIL | 210 nm height nano-pillar | High throughput Low cost |
Only applicable to polymers | [13, 15, 66] | |
| UV-NIL | 100 nm diameter nano-pillar | Lower deformation compared to NIL | Only applicable to cross-linkable polymers | [70] | |
| Colloidal lithography | 20 nm height pillars | Low consumption High throughput Easy to obtain colloidal crystals |
Low resolution, often a secondary process is required to refine structures | [61] | |
| Micro moulding | 3D riblet of shark skin | Good resolution and high throughput at micro-scale | Not suitable for nano-scale structure Limited to polymers |
[38, 43] | |
| Vacuum casting | 3D riblet of shark skin | Good resolution and high throughput at micro-scale Better resolution compared to micro moulding |
Not suitable for nano-scale structure Limited to polymers |
[39] | |
| Femtosecond laser | 20 µm elliptical structures with 200 nm nano-structures | Metal and non-metallic fabrication ability Good resolution and high throughput at micro-scale |
Not suitable for nano-scale structure especially under the 200 nm | [75] | |
| RIE | Pillar height 1.6 µm, with 350–750 nm diameter Pillar height 4 µm, 220 nm diameter |
Good resolution Metal and non-metallic fabrication ability |
High mask production costs | [81] | |
| FIB milling | |||||
| Ga+-FIB | 95 nm diameter pillars, length of 150–160 nm Nano holes 80–490 nm in diameter |
High resolution Maskless Higher throughput compared to He+ Metal and non-metallic fabrication ability |
Low throughput | [84, 102, 103] | |
| He+-FIB | Sub 10 nm | High resolution Maskless Metal and non-metallic fabrication ability |
Low throughput | [96, 104] | |
| Hydrothermal synthesis | 3 µm height pillars | Reliable Efficient Environmentally friendly Ability to control temperature and pressure |
Reaction takes place in a sealed vessel, reducing throughput | [9, 14, 90] | |
| Photolithography | Micro structure 1.5–20 µm | High throughput | Limited to photo sensitive material Low resolution |
[63, 65, 95] | |
| EBL | 5–10 nm | High resolution High throughput |
Only applicable to E-beam sensitive resists | [63, 96, 97, 100] | |