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Si (optical grade) CZ-111

Grade

Choose when maximum stiffness / cleavage-plane control is wanted, e.g. thin membranes, X-ray or diffractive elements.

High cost $$$$

Values for the CZ-111 condition

Other Si (optical grade) tempers and conditions

Si (optical grade) is listed in 3 conditions; see the grade overview at Si (optical grade).

Compare all 3 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
CZ-100Default
CZ
Default, lowest-cost optical silicon for 3–5 µm windows and lenses; interstitial oxygen gives a 9 µm absorption band, so it is less ideal for 8–12 µm.—12401,100 HV149 W/m·K
FZ high-resistivity
Pick for 8–14 µm thermal imaging, FTIR and THz optics where the CZ 9 µm oxygen band and free-carrier absorption must be eliminated.—12401,100 HV156 W/m·K
CZ-111This page
CZ
Choose when maximum stiffness / cleavage-plane control is wanted, e.g. thin membranes, X-ray or diffractive elements.—13001,150 HV149 W/m·K

What is Si (optical grade) CZ-111?

Si (optical grade) CZ-111 is Si (optical grade) in the CZ-111 grade — choose when maximum stiffness / cleavage-plane control is wanted, e.g. thin membranes, X-ray or diffractive elements. Si (optical grade) CZ-111 has a tensile strength of 130 MPa (18.9 ksi), stronger than 87% of glass grades. Elongation at break is 0% and the elastic modulus is 188 GPa (27.3 Msi). Si (optical grade) CZ-111 has a density of 2.33 g/cm³ (0.0841 lb/in³), lighter than 81% of glass grades. It melts at 1,414°C (2,577 °F). CZ-100 is the default condition FabDigit quotes; CZ-111 is available on request or by drawing note.

Advantages

  • Conducts heat well — 149 W/m·K (86.1 BTU/hr·ft·°F), better than 97% of glass grades
  • Stiff — 188 GPa (27.3 Msi), better than 93% of glass grades
  • Lightweight — 2.33 g/cm³ (0.0841 lb/in³), better than 81% of glass grades

Limitations

  • High embodied carbon — 120 kg CO₂/kg, worse than 94% of glass grades
  • Limited service temperature — 300°C (572 °F), worse than 80% of glass grades

Si (optical grade) CZ-111 properties

Typical room-temperature values for Si (optical grade) CZ-111; 15 are specific to this condition. Other listed values are Si (optical grade) reference data and may not represent this condition. Bars are the position among glass grades.

Physical5

Si (optical grade) CZ-111 has a density of 2.33 g/cm³ (0.0841 lb/in³), lighter than 81% of glass grades. It melts at 1,414°C (2,577 °F).

Density2.33 g/cm³0.08 lb/in³
Melting Point (Solidus)1,414°C2,577 °F
Refractive Index3.422
Light Transmission54%
Porosity0%

Mechanical12

Si (optical grade) CZ-111 has a tensile strength of 130 MPa (18.9 ksi), stronger than 87% of glass grades. Elongation at break is 0% and the elastic modulus is 188 GPa (27.3 Msi).

Elastic (Young's) Modulus188 GPa27.3 Msi
Shear Modulus57.5 GPa8.3 Msi
Bulk Modulus98 GPa14.2 Msi
Poisson's Ratio0.18
Tensile Strength (Ultimate)130 MPa18.9 ksi
Elongation at Break0%
Compressive Strength3,000 MPa435 ksi
Flexural Strength150 MPa21.8 ksi
Fracture Toughness (K_IC)0.8 MPa·√m0.73 ksi·√in
Hardness, Vickers1,150 HV
Hardness, Knoop1,150 HK
Hardness, Mohs7

Thermal5

Si (optical grade) CZ-111 is rated for continuous service to 300°C (572 °F). It conducts heat at 149 W/m·K (86.1 BTU/hr·ft·°F), better than 97% of glass grades. Thermal expansion is 2.6 µm/m·K (1.44 µin/in·°F).

Thermal Conductivity149 W/m·K86.1 BTU/hr·ft·°F
Specific Heat Capacity705 J/kg·K0.17 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)2.6 µm/m·K1.4 µin/in·°F
Max Service Temperature (continuous)300°C572 °F
Min Service Temperature-269°C-452 °F

Electrical5

Si (optical grade) CZ-111 is an electrical insulator with a dielectric strength of 30 kV/mm (762 V/mil) and a resistivity of 0.3 Ω·m.

Electrical Resistivity0.3 Ω·m1.18×10⁷ µΩ·in
Dielectric Strength30 kV/mm762 V/mil
Dielectric Constant (1 MHz)11.7
Dissipation Factor (1 MHz)0.001
Volume Resistivity30 Ω·cm

Chemical & Environmental2

Corrosion resistance is very good (80/100), better than 58% of glass grades.

Corrosion ResistanceVery good80/100
Chemical Resistance SummaryInsoluble in water and resistant to most mineral acids and organic solvents; rapidly etched by HF+HNO3 mixtures, by hot KOH/NaOH/TMAH and by halogen plasmas; oxidizes slowly in air above ~700 °C.

Sustainability4

Producing a kilogram of Si (optical grade) CZ-111 takes about 2,000 MJ of energy and emits 120 kg of CO₂ — more than 97% of glass grades. Typical recycled content is 2%.

Embodied Energy (primary production)2,000 MJ/kg859,846 BTU/lb
Embodied Carbon (primary production)120 kg CO₂/kg
Embodied Water1,500 L/kg180 gal/lb
Typical Recycled Content2%

Manufacturability2

Si (optical grade) CZ-111's machinability is poor (18/100, better than 52% of glass grades).

MachinabilityPoor18/100
PolishabilityExcellent95/100

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with Si (optical grade) CZ-111

Is Si (optical grade) easy to machine?

Diamond wire saw or ID saw for slicing, then diamond grinding/lapping; conventional cutting tools fail — SPDT is possible only with special tooling and gives limited tool life.

Can Si (optical grade) be welded?

Not weldable; join by optical contacting, silicon direct/fusion bonding, anodic bonding to glass, or low-stress epoxy/solder mounting.

Can Si (optical grade) be formed, bent or molded?

No plastic forming — parts are grown from the melt and generated to shape; aspheres and diffractive surfaces are ground or diamond-turned, deep features by KOH/DRIE etching.

What surface finishes work on Si (optical grade)?

Polish to <1 nm Rq and λ/10 flatness; almost always AR-coated (e.g. DLC or ZnS/YF3 stacks) because uncoated Fresnel losses cap transmission near 54%.

Si (optical grade) chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
Ointerstitial oxygen ~10–20 ppma in CZ (9 µm absorption); <0.5 ppma in FZ08×10⁻⁴
Csubstitutional carbon, <1 ppma typical0 – 5×10⁻⁴1×10⁻⁴
Bp-type dopant, set to reach target resistivity≈ 5×10⁻⁷5×10⁻⁷
Pn-type dopant, set to reach target resistivity≈ 5×10⁻⁷5×10⁻⁷
Sielectronic/optical purity, metallic impurities typically <1 ppba≥ 100 (balance)—

Si (optical grade) CZ-111 — frequently asked

What is Si (optical grade) CZ-111 used for?

Si (optical grade) CZ-111 is typically used for thermal imaging lenses, IR windows, beamsplitters and laser optics substrates. In short: lightweight LWIR lens material; high thermal conductivity window; always AR-coated.

What is the tensile strength of Si (optical grade) CZ-111?

Si (optical grade) CZ-111 has a typical tensile strength of 130 MPa (18.9 ksi) — stronger than 87% of glass grades. Strength varies by condition: see the 3 listed tempers.

Is Si (optical grade) CZ-111 easy to machine?

Not especially — machinability is rated poor (18/100, better than 52% of glass grades). Diamond wire saw or ID saw for slicing, then diamond grinding/lapping; conventional cutting tools fail — SPDT is possible only with special tooling and gives limited tool life.

Can Si (optical grade) CZ-111 be welded?

Not weldable; join by optical contacting, silicon direct/fusion bonding, anodic bonding to glass, or low-stress epoxy/solder mounting.

What surface finishes work on Si (optical grade) CZ-111?

Polish to <1 nm Rq and λ/10 flatness; almost always AR-coated (e.g. DLC or ZnS/YF3 stacks) because uncoated Fresnel losses cap transmission near 54%.

Can Si (optical grade) CZ-111 be formed, bent or molded?

No plastic forming — parts are grown from the melt and generated to shape; aspheres and diffractive surfaces are ground or diamond-turned, deep features by KOH/DRIE etching.

What is the maximum service temperature of Si (optical grade) CZ-111?

Si (optical grade) CZ-111 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. Handbook of Optical Constants of Solids (silicon chapter) — Academic Press / Palik (1998)
  2. Silicon (Si) optical material data sheet — Crystran Ltd (2023)
  3. What is the Young's Modulus of Silicon? — Journal of Microelectromechanical Systems (Hopcroft, Nix, Kenny) (2010)
  4. SEMI MF84 — Test Method for Measuring Resistivity of Silicon Wafers — SEMI (2017)
  5. ASTM F1188 / ASTM F1391 — interstitial oxygen and substitutional carbon in silicon by IR — ASTM (2019)
  6. CRC Handbook of Chemistry and Physics, physical constants of silicon — CRC Press (2022)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.