CdTe POLY
Grade
POLY = polycrystalline / hot-pressed CdTe
Choose as low-cost 5N–6N feedstock: PV thin-film sputtering targets, sublimation source charges and crystal-growth raw material, not for imaging optics.
Values for the POLY condition
Other CdTe tempers and conditions
CdTe is listed in 3 conditions; see the grade overview at CdTe.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Chlorine-compensated semi-insulating detector grade | Choose for room-temperature X-ray/gamma spectroscopy detectors needing >10^9 Ω·cm resistivity and good charge transport. | — | 22 | 0 | 48 HV | 6 W/m·K |
Epi-ready (211)B oriented substrate for HgCdTe | Choose when a lattice-matched, low-EPD, epi-polished wafer is needed for HgCdTe infrared focal-plane growth. | — | 25 | 0 | 45 HV | 7 W/m·K |
POLYThis page Polycrystalline / hot-pressed CdTe | Choose as low-cost 5N–6N feedstock: PV thin-film sputtering targets, sublimation source charges and crystal-growth raw material, not for imaging optics. | — | — | — | — | — |
What is CdTe POLY?
CdTe POLY is CdTe in the POLY grade — choose as low-cost 5N–6N feedstock: PV thin-film sputtering targets, sublimation source charges and crystal-growth raw material, not for imaging optics. The elastic modulus is 35 GPa (5.08 Msi). CdTe POLY has a density of 5.8 g/cm³ (0.21 lb/in³), heavier than 97% of glass grades. It melts at 1,092°C (1,998 °F).
Advantages
- Easy to machine — 40/100, better than 80% of glass grades
Limitations
- Heavy — 5.8 g/cm³ (0.21 lb/in³), worse than 97% of glass grades
- Hard to polish — 45/100, worse than 92% of glass grades
- Low fracture toughness — 0.2 MPa·√m (0.182 ksi·√in), worse than 91% of glass grades
- Low stiffness — 35 GPa (5.08 Msi), worse than 86% of glass grades
- High embodied carbon — 45 kg CO₂/kg, worse than 84% of glass grades
CdTe POLY properties
Typical room-temperature values for CdTe POLY; 10 are specific to this condition. Other listed values are CdTe reference data and may not represent this condition. Bars are the position among glass grades.
Physical5
CdTe POLY has a density of 5.8 g/cm³ (0.21 lb/in³), heavier than 97% of glass grades. It melts at 1,092°C (1,998 °F).
Mechanical9
The elastic modulus is 35 GPa (5.08 Msi).
Thermal5
CdTe POLY is rated for continuous service to 400°C (752 °F). It conducts heat at 6.2 W/m·K (3.58 BTU/hr·ft·°F), better than 71% of glass grades. Thermal expansion is 5.9 µm/m·K (3.28 µin/in·°F).
Electrical3
CdTe POLY has an electrical resistivity of 100 Ω·m.
Chemical & Environmental2
Corrosion resistance is fair (50/100), worse than 80% of glass grades.
Sustainability3
Producing a kilogram of CdTe POLY takes about 600 MJ of energy and emits 45 kg of CO₂ — more than 86% of glass grades. Typical recycled content is 15%.
Manufacturability2
CdTe POLY's machinability is fair (40/100, better than 80% of glass grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CdTe POLY
Is CdTe easy to machine?
Very soft and cleavage-prone — core drill/wire-saw with copious coolant, then single-point diamond turn at light depth of cut; never dry-grind (toxic Cd dust, extraction and wet handling mandatory).
Can CdTe be welded?
Not weldable; assemble by low-stress elastomer or optical-cement mounting, or metallize (Au/In) for soldered detector contacts.
Can CdTe be formed, bent or molded?
No plastic forming — shapes come from Bridgman/VGF/THM ingot growth or hot pressing of polycrystalline powder for targets.
What surface finishes work on CdTe?
Lap with alumina/diamond, chem-mechanical finish in bromine-methanol or CMP slurry for epi-ready wafers, then AR-coat (ZnSe/YF3 stacks) for 10.6 µm; keep dry, surfaces tarnish in humid air.
CdTe 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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cdstoichiometric CdTe; optical/detector grades from 6N–7N feedstock | 46.7 – 47 | 46.84 |
| Clintentional compensating dopant only in CdTe:Cl detector grade | 0 | 5×10⁻⁴ |
| Teslight Te excess common in as-grown Bridgman ingots | ≥ 53 (balance) | — |
CdTe POLY — frequently asked
What is CdTe POLY used for?
CdTe POLY is typically used for CO2 laser windows/lenses, IR optics, photorefractive/electro-optic devices and IR detector substrates. In short: 0.9 to 16 µm transmission; standard HgCdTe substrate; toxic cadmium handling required.
Is CdTe POLY easy to machine?
Not especially — machinability is rated fair (40/100, better than 80% of glass grades). Very soft and cleavage-prone — core drill/wire-saw with copious coolant, then single-point diamond turn at light depth of cut; never dry-grind (toxic Cd dust, extraction and wet handling mandatory).
Can CdTe POLY be welded?
Not weldable; assemble by low-stress elastomer or optical-cement mounting, or metallize (Au/In) for soldered detector contacts.
What surface finishes work on CdTe POLY?
Lap with alumina/diamond, chem-mechanical finish in bromine-methanol or CMP slurry for epi-ready wafers, then AR-coat (ZnSe/YF3 stacks) for 10.6 µm; keep dry, surfaces tarnish in humid air.
Can CdTe POLY be formed, bent or molded?
No plastic forming — shapes come from Bridgman/VGF/THM ingot growth or hot pressing of polycrystalline powder for targets.
What is the maximum service temperature of CdTe POLY?
CdTe POLY is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Handbook of Optical Constants of Solids (CdTe chapter) — Academic Press (Palik ed.) (1998)
- Landolt-Börnstein III/17b, 41B — II-VI Compound Semiconductors — Springer (1999)
- CdTe infrared optical material datasheet — Crystran Ltd (2023)
- CdTe and CZT crystal / substrate specifications — Coherent (II-VI Incorporated) (2023)
- CRC Handbook of Chemistry and Physics, 104th ed. — CRC Press (2023)
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.