Sivalues describe: float zone
Semiconductor equipment & lithographyChipmakers (foundries & IDMs)
Why it wins
The consumable that matches the wafer: etch electrodes, focus and edge rings machined from CZ ingot, eroding into nothing the process minds.
Why not the alternative
Any metal ring contaminates; SiC costs more and is reserved for hotter, longer-life positions.
Watch out
Resistivity and dopant are process parameters, not details: specify them.
Properties
The values below are candidate: compiled from the sources named, not yet individually validated.
Provisional provenance: Semiconductor chamber materials and plasma-resistant coating literature.
Wet cleaning
| Recipe | RCA: SC-1 for particles and organics, HF dip to strip oxide, SC-2 for metals, ultrapure cascade rinse, spin dry |
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| Forbidden | any metallic contamination in the bath: Cu and Fe diffuse in and kill devices |
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| Limit | metal contamination measured in atoms per cm², the tightest cleaning spec in industry |
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Vacuum and outgassing
| Outgassing, unbaked (10 h) | 5e-10 mbar·L/s/cm² |
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| Outgassing, baked | 5e-13 mbar·L/s/cm² |
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| Vapour pressure | negligible below 1200 °C |
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Temperature
| Bake, assembled | 450 °C |
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| Vacuum degas | 1000 °C |
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| Braze / H2 firing | 1200 °C |
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| Metallurgical limit | melts 1414 °C |
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Thermal
| CTE | 2.6 ppm/K |
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| Thermal conductivity | 150 W/m·K |
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| Specific heat | 700 J/kg·K |
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| Emissivity | 0.6 |
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| Melting / softening | 1414 °C |
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Mechanical
| Strength | 165 flex MPa |
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| Elongation | nil |
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| Young's modulus | 130 GPa |
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| Hardness | 1000 HV |
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| Density | 2.33 g/cm3 |
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Electrical and magnetic
| Relative permeability | diamagnetic |
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| Resistivity | doping dependent |
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| Dielectric strength | 30 kV/mm |
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Engineering
| Corrosion | oxide-passivated |
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| Joining | anodic and fusion bonding |
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| Process notes | the RCA clean is the reference every other wet bench descends from |
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| Availability and cost | commodity by diameter |
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Grades
| CZ silicon, low resistivity doped | RF-coupled electrodes and rings |
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| High purity float zone | where metallic background matters most |
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Sources · 1
- Y-based coatings and Si ceramics in plasma tools
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