Wet etching | - |
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Si etching | KOH |
Wet oxide etching | BOE, HF, HCl |
Wet metal etching | Au, Cr |
Immersion cleaning | SC1, HCl |
Dry etching | - |
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DRIE | Si |
RIE | Poly-Si, SiO2, SiN, Polyimide, Parylene, and more |
Plasma cleaning | Plasma cleaning and plasma ashing are both possible. |
Metallization | - |
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Evaporation | Au, Cu, Ti, Cr, Pt, Ni, Al |
Sputtering | Cr, Au, Ti, TiW, Cu |
Materials | - |
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LPCVD | Low stress nitride, low stress polysilicon, low temperature oxide, phosphosilicate glass (PSG) |
Polymers | Polyimide, parylene-C |
Lithography | - |
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Contact lithography | Negative/positive resists, SU-8 and polyimide processing |
Projection lithography | Negative/positive resists, SU-8 and polyimide processing |
Backside alignment | Negative/positive resists, SU-8 and polyimide processing |
Post processing | - |
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Dicing | Wafer saw is designed for silicon, glass, fused silica, quartz, sapphire, and more. |
HF liquid release | Liquid HF is used to release devices from SOI wafers. |
Critical CO₂ drying | Removes liquids and surface tension forces via CO₂. |
Wafer bonding | - |
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Types | Fusion, glass-glass, silicon-glass, eutectic, anodic |
Metrology | - |
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Techniques | SEM, profilometry, infrared inspection, interferometry |
Film analysis | Film stress, thickness, or resistivity |
Thermal processing | - |
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Si oxidation | Silicon oxide is grown on a wafer by diffusing it onto a wafer at high temperature. |
Annealing | Wafers are brought to high temperatures and slowly cooled. |
Additional options | - |
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Wafer thinning | Wafer thickness is reduced by backgrinding. |
Maskless alignment | Photo exposure is done without physical masks and a laser is used for direct pattern writing. |
Wafer polishing | Wafers are polished with slurry and pads. |
Ion implantation | Doping is achieved by accelerating ions into the wafer. |
PECVD | Chemical vapor deposition technique using plasma to lower the activation energies. |
Parylene deposition | Parylene is deposited as a transparent film across all wafer surfaces. |
Laser dicing | The wafer is diced with a laser instead of a wafer saw. |
FIB | Structures on the wafer are cut with a focused ion beam. |