Comment on The Inside of Sensirion's SCD4x
Scafir@discuss.tchncs.de 5 days ago
Thanks! I recently was in the headquarters/production facilities of Sensiron which interestingly are located near Zurich in Switzerland. It’s quite rare to see production of IC’s in this country. The “magic sauce” of the sht40 and friends is the deposition of a certain matieral (can’t remember which one) on top of the classic silicon die.
Sal@mander.xyz 5 days ago
That is very cool! I did not know they were producing in Switzerland. I would like to visit. Do you know if they routinely open to the public?
I wonder if the “magic sauce” is a polyimide. Those polymers are often used as the dielectric layer to make capacitors that are humidity-sensitive. These polymers have sites into which water molecules can reversibly dock such that the occupancy at equilibrium is proportional to the % relative humidity.
Scafir@discuss.tchncs.de 4 days ago
I do not know if they are open to the public per se, but it seemed to be something they do quite regularly. Concerning the material, they say on their site that it is a “polymer”. On this page they go quickly over how the measurements work.
I was actually not visiting sensirion, but lumiphase. A smaller company they are investing in which does optical chips. It’s interesting stuff, they are also depositing unusual materials on the silicon wafer to make their chips work.
Sal@mander.xyz 4 days ago
Awesome, thanks! I will look into it.