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This material is hardly exceptionally dangerous. Its close cousin Gallium Arsenide has been nearly the exclusive source of Yellow, Red, and Infrared LED's sinc

This material is hardly exceptionally dangerous. Its close cousin Gallium Arsenide has been nearly the exclusive source of Yellow, Red, and Infrared LED's since the 70's. The screen you're looking at now would not exist without arsenide compounds, both for lights and for other circuit components. While you could probably make yourself sick by taking old chips of this nature, grinding them up, and inhaling or eating them, or engaging in an accident with their raw materials during their manufacture, they rank pretty low on the list in terms of practical toxicity. Arsenic is a common trace element, and even (in small quantities) has been used to ward off disease in chicken and cattle. It's not good for you, but this is a positive development, not a poisonous watershed.

strainer 8y ago
If not limited to trace amounts for microscopic components, in the heat spreading role there could be demand for it in much greater quantity than elementally similar LED pigments. Most manufacturing materials do not require such careful treatment and disposable -thankfully. The concern is not just about unusual behavior such as 'grinding up and eating'. This is a particularly hazardous material - as documented.
- civilitty 8y ago
  You're exaggerating how dangerous BAs would be in this situation. As far as I know, useful single crystal boron arsenide is very expensive to make in industrial quantities and it's too brittle to be used as a large heatsink - at best you can grow a several micron thick layer of it on a semi-flexible substrate like for solar panels. Instead, I'm guessing their design uses small quantities of single crystal BAs to interface between the wafer and the rest of the chip package so it would better transfer heat from the internal silicon to a regular heatsink. Thermal conductivity at that interface is a hard limit to how fast the heatsink can draw heat from the chip package and since its contained, toxicity is largely a concern for recycling.
  - strainer 8y ago
    Its a concern for manufacturing, containment and disposal. In few places public disposal and recycling facilities guarantee complete compliance. The materials hazard specs are not exaggerated, they are intended to be taken seriously as they are stated. "Instead, I'm guessing their design..." There were no designs indicated here, only research on the crystals thermal properties with the vague mention of "electronic cooling" and "potential large-scale applications"
    - mng2 8y ago
      Absolutely, arsenic-containing materials have the potential to be extremely dangerous. Unscrupulous GaAs manufacturers have put their employees at risk in the past. [0]: https://www.eastbayexpress.com/oakland/the-axt-way/Content?oid=1073304 https://www.eastbayexpress.com/oakland/the-axt-way/Content?o...

strainer 8y ago

If not limited to trace amounts for microscopic components, in the heat spreading role there could be demand for it in much greater quantity than elementally similar LED pigments. Most manufacturing materials do not require such careful treatment and disposable -thankfully. The concern is not just about unusual behavior such as 'grinding up and eating'. This is a particularly hazardous material - as documented.

civilitty 8y ago
You're exaggerating how dangerous BAs would be in this situation. As far as I know, useful single crystal boron arsenide is very expensive to make in industrial quantities and it's too brittle to be used as a large heatsink - at best you can grow a several micron thick layer of it on a semi-flexible substrate like for solar panels. Instead, I'm guessing their design uses small quantities of single crystal BAs to interface between the wafer and the rest of the chip package so it would better transfer heat from the internal silicon to a regular heatsink. Thermal conductivity at that interface is a hard limit to how fast the heatsink can draw heat from the chip package and since its contained, toxicity is largely a concern for recycling.
- strainer 8y ago
  Its a concern for manufacturing, containment and disposal. In few places public disposal and recycling facilities guarantee complete compliance. The materials hazard specs are not exaggerated, they are intended to be taken seriously as they are stated. "Instead, I'm guessing their design..." There were no designs indicated here, only research on the crystals thermal properties with the vague mention of "electronic cooling" and "potential large-scale applications"
  - mng2 8y ago
    Absolutely, arsenic-containing materials have the potential to be extremely dangerous. Unscrupulous GaAs manufacturers have put their employees at risk in the past. [0]: https://www.eastbayexpress.com/oakland/the-axt-way/Content?oid=1073304 https://www.eastbayexpress.com/oakland/the-axt-way/Content?o...