This stuff is fascinating, especially the challenges in fabrication as the theoretical limits are approached. I do have a question, if an expert could help explain. The article says,
"With FMC’s proprietary hafnium oxide, the standard gate dielectric can be made ferroelectric—even for film thicknesses that compare to the one used in standard logic transistors. This proprietary hafnium oxide integrates extremely well with all current and future processes utilizing HKMG. Therefore, a scalable ferroelectric FET finally becomes possible."
What is proprietary about the hafnium oxide? Is it the process of creating it, or the molecule itself?
If I understand it correctly, it is the process of depositing the HfO2 onto the wafer in a way that it retains its ferroelectric properties and is compatible with other chipmaking processes that is proprietary. Depositing it improperly would result in defects at the junction between the HfO2 and the underlying gate that would render the FeFET nonfunctional.
When I was in semiconductor manufacturing, we tried using a hafnium oxide layer in the capacitor dielectric for our DRAM. It did not go well, if I recall correctly (10 years back). Not for design reasons -- we were using it for its dielectric properties, not its ferromagnetic ones -- but for process reasons. It was hell on the diffusion furnaces. Flakes everywhere, wafers sticking. Lots of angry morning meetings.
Hafnium oxide itself doesn't seem to be proprietary, and neither does the process of producing thin films that have ferroelectric properties[1]. My guess is that they've made some additional modifications to the compound and/or process.
I'm venturing way outside of my field here, so I could be completely wrong.
"With FMC’s proprietary hafnium oxide, the standard gate dielectric can be made ferroelectric—even for film thicknesses that compare to the one used in standard logic transistors. This proprietary hafnium oxide integrates extremely well with all current and future processes utilizing HKMG. Therefore, a scalable ferroelectric FET finally becomes possible."
What is proprietary about the hafnium oxide? Is it the process of creating it, or the molecule itself?